Effects of Pressure and Particle Size on the Carbonization of a Packed Bed of Biomass

A THESIS SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAIʻI AT MĀNOA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF

MASTER OF SCIENCE IN MECHANICAL ENGINEERING

May 2014

Gregory Patrick Specht

Thesis Committee:

Michael J. Antal Jr., Chairperson Weilin Qu Beei-Huan Chao

We certify that we have read this thesis and that, in our opinion it is satisfactory in scope and quality as a dissertation for a degree of Master of Science in Mechanical Engeineering.

THESIS COMMITTEE

Chairperson

iii

Abstract

A relatively new technique for charcoal production has been developed called Flash

CarbonizationTM and has proven to be efficient and most importantly fast. The technique begins with a packed bed of biomass pressurized at 1-2 MPa. A fire is ignited at the bottom of the bed while air is introduced through the top. The flame travels up the bed converting the biomass to bio carbon otherwise known as charcoal. One of the most important metrics a charcoal has is its Fixed Carbon Yield

(yfc) or the percentage of carbon left in it after it is carbonized. Many factors affect the yfc of charcoal three in particular were investigated in this thesis; feedstock, pressure, and particle size.

Each feedstock that was used in the FC process and analyzed in this thesis was sent out to a lab to discover its elemental composition. Using this data calculations were performed to discover the highest theoretical yfc each feedstock could produce. A yfc between 33 and 36% was discovered which is not surprising since all feedstocks were various wood types. In experimentation it was shown that each of these feedstocks had similar yfc for identical operational conditions.

The pressure at which an experiment was performed had a much more significant affect on yfc.

Low pressure resulted in low yfc and as pressure increased so did yfc. Experimentation was limited to

2.17 MPa and was not able to see if this trend continued indefinitely. Increasing pressure beyond certain thresholds can also be very dangerous and have caused runaway reactions causing pressures and temperatures to spike in a matter of seconds.

Particle size also has a great affect on yfc very similar to pressure, as particle size increases so does yfc. The one difference is that once a feedstock is larger than sawdust’s the yfc levels off. This can prove beneficial since most material will need little preparation work in order to achieve the highest yfc.

Acknowledgements

I would first like to thank my advisor Dr. Michael J. Antal, Jr. who did not give up on me even after I gave up on myself. He pushed me to be the best that I could be and would accept nothing less. I would also like to thank our collaborators over at SINTEF in Norway for sharing their work with us and giving me the opportunity to research at their facilities for a summer. A special thanks are extended to Dr. Beei-Haun

Chao and Dr. Weilin Qu for serving on my thesis committee and willing to answer all my endless questions throughout class. To Dr. Brian Bingham for going above and beyond his responsibilities to help out a student in need and making class a time to look forward to. I would also like to recognize all the fellow researchers at R3 labs who made the long hours more enjoyable.

I would also like to thank my mother for being so supportive throughout my entire life. She is responsible for shaping me into the man I am today. My father for giving me my passion for science and adventure, while teaching me to never follow the herd. My brothers for sharing in the joys and pains of our childhood. My friends and family for always being there for me even when I am halfway across the world. Last and most importantly I would like to thank Rachel for actually moving halfway across the world with me and making every day with her better than the last.

Table of Contents

Abstract ...... iv Acknowledgements ...... v List of Tables ...... viii List of Figures ...... ix Nomenclature ...... x Chapter 1: Introduction ...... 1 1.1 Background ...... 1 1.2 Purpose of Thesis ...... 2 Chapter 2: Charcoal Production and Use Worldwide ...... 3 2.1 The significance of Charcoal Production ...... 3 2.2 Charcoals used as a fuel vs. making silicon ...... 3 2.3 Basic Terminology ...... 4 2.3.1 Moisture Content ...... 4 2.3.2 Proximate analysis ...... 6 2.3.3 Common metrics ...... 7 2.4 History of Charcoal Production ...... 8 2.5 Advantage of Flash CarbonizationTM ...... 9 Chapter 3: Lab Scale Reactor ...... 10 3.1 Reactor Description ...... 10 3.1.1 Pressure Vessel and Canister ...... 10 3.1.2 Primary air source ...... 11 3.1.3 Electric Heater ...... 12 3.1.4 Exhaust ...... 12 3.1.5 Common Feedstocks ...... 13 3.1.6 LabVIEW ...... 13 3.2 Flash Carbonization Experiment Overview ...... 14 3.2.1 Preparation for Experiment ...... 14 3.2.2 Experiment Procedure ...... 15 3.2.3 Examination of Results ...... 16 3.3 Operational Problems ...... 16 3.3.1 Pressure Control...... 16

3.3.2 Incomplete Carbonization ...... 17 Chapter 4: Charcoal and Fixed Carbon Yield ...... 18 4.1 Parameters That Affect Fixed Carbon Yield ...... 18 4.1.1 Feedstock ...... 18 4.1.2 Correction from wet to dry ...... 20 4.1.3 Particle size ...... 22 4.1.4 Pressure ...... 25 4.2 Thermochemical Equilibrium Calculations...... 27 4.2.1 Thermochemical Equilibrium Explained ...... 27 4.2.2 Example Calculations ...... 28 4.2.3 STANJAN Calculations Run on Feedstock ...... 29 4.2.4 Comparison of Theoretical Yield vs Achieved Yield ...... 32 Chapter 5: Conclusion ...... 33 5.1 Future work ...... 33 5.2 Conclusion ...... 33 Appendix A: 130109 Demo Reactor Run Report ...... 35 Appendix B: STANJAN Simulation Results ...... 38 Works Cited ...... 80

vii

List of Tables

Table 4.1 Ultimate Analyses of Oak and Sweet Gum Woods and the Calculated Theoretical Fixed-Carbon Yields yfC ...... 19

Table 4.2 Huffman’s results on a wet basis as a percentage of total mass ...... 20

Table 4.3 New ultimate analysis corrected for moisture content ...... 21

Table 4.4 Example calculations run on previous results ...... 21

Table 4.5 Charcoal produced in nitrogen atmosphere ...... 22

Table 4.6 Charcoal and Fixed-Carbon Yields Realized at Elevated Pressure in the FC Reactor. . . . 25

viii

List of Figures

Figure 3.1 Schematic of Lab Scale Reactor ...... 10

Figure 3.2 Screen shot of LabVIEW program ...... 14

Figure 4.1 Graph of red oak and sweet gum particle size vs char yield ...... 23

Figure 4.2 SEM micrographs of red oak charcoal sample produced in the muffle furnace at 0.1 MPa ...... 26

Figure 4.3 SEM micrographs of Cowboy oak charcoal sample produced in the FC reactor at 2.17 MPa ...... 26

Figure 4.4 Results of STANJAN simulation ...... 31

Figure 4.5 Parity plot of multiple charcoals theoretical yfc vs experimental yfc ...... 32

Figure A.1 Entire demo reactor experiment pressure graph...... 35

Figure A.2 Demo reactor 4 second pressure spike pressure graph...... 35

Figure A.3 Demo reactor 18 second pressure spike pressure graph...... 36

Figure A.4 Demo reactor 6 second pressure spike pressure graph...... 36

Figure A.5 Demo reactor pressure peak pressure graph...... 36

Nomenclature

MC Moisture Content

Mfeed, Wet Mass of the feed before drying

Mfeed, Dry Mass of the feed after drying

Mfc Mass of the fixed carbon

Mfeed, Ash Mass of the ash in the feed

Mchar Mass of the charcoal

Asp Area of the solar panel

E20y Energy a solar panel would create in 20 years

Ewood Energy wood would make if burned in a power plant VM Volatile matter ychar Charcoal yield yfc Fixed carbon yield PV Pressure vessel

SEM Scanning Electron Microscope

Kp Equilibrium constant

Chapter 1:

Introduction

1.1 Background

The method of the Flash CarbonizationTM is truly a unique yet simple way to produce charcoal in a quick and efficient manner. The technique was designed by Michael J Antal with the help of many other colleagues along the way. Flash CarbonizationTM was not thought up overnight but instead had multiple iterations to fully develop the technology. It all began back in 1983 when a stainless steel pressure vessel in conjunction with a Setaram DSC were used to investigate the effects pressure and purge gas flow rates had on cellulose pyrolysis. It was discovered that pressure and low flow rate were shown to improve charcoal formation [1]. This led to the creation of a small bomb type reactor in 1989. Made out of a pipe sealed on both ends and placed into a furnace. It achieved charcoal yields as high as 44% and eventually received a patent by the University of Hawaii [2].

The next step came in 1996 when a process development unit (PDU) was constructed to prove the technology on a larger scale. It consisted of a canister inside a vessel heated by first 4kW electrical heaters surrounding the outside of the canister. A back pressure regulator is piped into the vessel preventing the pressure from exceeding 0.7 MPa. The electrical heater was later replaced with a gas heater because gas was more economical. Due to the impracticality of the large PDU a smaller more practical unit was designed and built shortly after [2]. Unfortunately the gas heater was too large and didn’t get hot enough so a move back to an electrical heaters was implemented. In 2000 an electrical heater was added to the center of the feedstock to improve the uniformity of the charcoal. The back pressure regulator was also increased to 1 MPa [3]. This design still heavily relied on the electrical heaters running throughout the experiment which consumed a large amount of power.

This last iteration is what can be seen in the lab today. In 2003 Michael Antal and colleagues wondered if a self-burning bed could still produce high yields of charcoal. This next proposal added an air delivery system to the top of the bed and an electric heater at the bottom to accomplish just that [4].

A flame would be ignited in the bottom then move up the bed as air was introduced from the top.

Experimentation showed that it was possible to burn the feedstock itself to create charcoal while using nearly ten times less energy in heating. A large scale reactor was built soon after which was 0.9-m diameter by 2.7-m tall to demonstrate the technology on an industrial scale [4].

1.2 Purpose of Thesis

Since the Flash CarbonizationTM technique has shown very promising results there has been efforts to use the technology to convert different waste products such as sawdust, agricultural waste, and sewage sludge into charcoal. In order to demonstrate the feasibility of this technology it is important to understand the effects pressure, particle size, and feedstock have on the resulting charcoal. This thesis is meant to give further insight into each of these factors so more informed decisions can be made if a commercial facility is constructed and operated.

Chapter 2:

Charcoal Production and Use Worldwide

2.1 The significance of Charcoal Production

Charcoal has been one of the most versatile and useful substances throughout human history. Its past stretches thousands of years back to when workers used shallow charcoal pits to smelt tin [5] and continues to be used today in a wide variety of applications. For instance the ability for charcoal to be burned cleaner than most other fuels and at higher temperatures makes it a great candidate for cooking, fireworks and heating forges. Charcoal’s composition is very low in ash and high in carbon making it an ideal reducing agent in silicon and steel production. It has a high surface area to volume ratio making it favorable for filtration and medical applications. With this many uses it’s no surprise that charcoal is used by billions of people worldwide.

2.2 Charcoals used as a fuel vs. making silicon

Charcoal can be burned as a fuel to make electricity but it can also be used to turn quartz into pure silicon for solar panels. Below in Equation 2.1 [6]is the chemical equation to form pure silicon.

(2. )

It is an interesting point to talk about which of the two produces more energy: burning wood in a steam power plant or making solar panels from the charcoal and employing them here in Hawaii.

Equation (2.1) states it would take roughly 0.86 kg of carbon to make 1 kg of silicon. In the real world it takes approximately 1.4 kg of charcoal to make 1 kg of Si due to the fact charcoal is comprised of things other than carbon and there are always losses associated with any process.

Some basic facts must be known in order to answer this question. The density of silicon is 2.329 g/cm3 and the thickness of a typical solar cell is .2 mm with .13 mm of silicon lost to processing [7]. The efficiency of solar panels can be averaged around 15% [8] with a worsening of its efficiency by 1% a year for 20 years [9]. A common value for steam turbine power plants’ efficiency is 30% and as seen often in the lab 33% of wood is converted into charcoal. Wood has a lower heating value of 5 kWh/kg. The last piece of this puzzle is that Hawaii receives on average 5kWh/m2/day. Now that all the constants are taken care of the calculations are described below.

(2.2)

(2.3)

(2.4)

Where Asp is the area of the solar panel, E20y is the energy a solar panel would create in 20 years, and Ewood is the amount of energy the wood that was used to make the charcoal would have produced in a power plant. Obviously there are other things to consider like price and processing the solar panels but it is obvious that much more energy comes from solar panels than direct burning of wood.

2.3 Basic Terminology

2.3.1 Moisture Content

All living organisms that humanity knows of use water in most daily functions. This makes water a significant contribution to organic material’s overall mass. The amount of water in different organic matter varies greatly based on what type of material is being used. For instance a fast growing grass-like plant will have a higher percentage of water mass than a slow growing hardwood tree. The conditions the material was stored in (i.e. humidity and temperature) also have a huge impact on the amount of

4 water remaining in any given organic material. Therefore the mass of the feedstock should not be seen as a constant and can vary especially over long periods of time. It is important to take a moisture analysis of a sample of feedstock close to the time it was used in an experiment.

In order to take a moisture analysis it will vary slightly based on the material that is being analyzed (i.e. different feedstocks and charcoal) but the following is for a sample of charcoal. A sample must be dried in an oven until all the moisture has been removed. In essence this is when the sample does not lose more mass between baking periods. The exact guidelines that are followed in the R3 labs are laid out in ASTM E 1756-95 [10]. The process begins with an empty crucible being fired in an oven at

105˚C for at least one hour. The crucible is then removed and allowed to cool in a desiccator for an hour.

After which the crucible is weighed on a scale capable of reading one tenth of a milligram and then recorded. The crucible is then placed back into the oven and the process is repeated until the weight of the empty crucible does not change by more than half of a milligram. This reheating process can be assumed for any process at its corresponding temperature unless otherwise stated. The sample is then prepared by first randomly selecting approximately 10 grams of charcoal from a batch and grinding it down then sifted and the powder which fits between the 20 mesh and 100 mesh screens is used. The sample is then allowed to equilibrate with the lab for at least 24 hours to ensure any moisture lost during grinding has been regained.

Approximately a one gram sample is then placed in the crucible. The full crucible is then placed in the oven, with the lid off, at 105˚C for at least 3 hours but no longer than 72 hours. The crucible is then placed in a dissector for one hour and then weighed. The difference before and after the cookings is the mass of water in the sample. The moisture content can be reported on a wet or dry basis as in the following equations.

(2.5)

(2.6)

MCWB, MCDB, mH2O, mBio, Wet, and mBio, Dry represent moisture content wet basis, moisture content dry basis, water mass, mass of the feedstock before drying and after drying respectively.

2.3.2 Proximate analysis

The proximate analysis is a method used to discover a charcoal samples volatile matter (VM), ash (ASH) and fixed carbon (FC). The analysis we use to discover these properties is laid out in ASTM D 1762-84

[11]. The analysis begins with a previously dried sample as explained in section 2.3.1 The crucible is then placed into an oven at 950˚C for 11 minutes with the lid on. This is done to prevent combustion in the crucible but still driving away the volatile matter. It is then cooled in a desiccator for one hour and weighed. The crucible is then again returned to an oven at 750˚C for a minimum of 6 hours with its lid off. Most charcoals will ignite between 375˚C and 500˚C [12] so 750˚C is a safe temperature to ensure the charcoal combusts. This is done to completely combust the remaining charcoal so only ash remains.

Once removed it is stored in a crucible for an hour and then weighed. The VM, ASH and FC are described in the equations below.

(2.7)

(2.8)

(2.9)

Where mchar is the mass of the dry charcoal, mcarbon is the mass of the carbon without VM and mash is the mas of the ash. Proximate analysis are a quick analysis usually able to be completed within a week and give a good sense of what kind of charcoal was produced. The ultimate goal would be to be

6 able to control to a certain degree what percentage of each component a finished product will end up with.

With this information one can rank various charcoals depending on their use of the charcoal. In general low ASH content less than 1%, low VM between 7-9%, and high FC above 90% are more desirable charcoals. Some forms of charcoal do not follow this structure for example charcoal derived from sewage sludge can have very high levels of ASH some as high as 50% but has shown to be an excellent soil amendment for growing crops.

2.3.3 Common metrics

Most scientists in different fields have vocabulary specific to their line work. This is also true in the field of charcoal production. One of the most important things to define would be charcoal. Webster defines charcoal as “A dark or black porous carbon prepared from vegetable or animal substances.” Clearly this definition is somewhat lacking in specifics and that is true also in the real world applications of charcoal.

Since charcoal is used in so many different applications what is good charcoal in one field is terrible charcoal in a different field. For instance charcoal used for soil amendment would not be good to cook ones food with. Therefore it is more important to define the metrics associated with charcoal.

One very useful metric, especially in the field of silicon production, is fixed carbon percent. This is due to the fact that the carbon is the useful part of the charcoal in making silicon. In the field of charcoal production it is valuable to compare its mass to the mass of the dry feedstock. This would be referred to as charcoal yield and described in Equation 2.10 below. Unfortunately all charcoals are not created equal; some contain more ash and others contain more volatile matter so another useful metric is the Fixed Carbon Yield, yfc, and is described in equation 2.11 below.

(2.10)

(2.11)

In the above equation mFC is the mass of the fixed carbon, mFeed, Dry is the mass of the dry feedstock, and mFeed, Ash is the mass of the ash in the feed.

2.4 History of Charcoal Production

Charcoal production has not changed much in the past 5000 years. The traditional process begins with making a large pile of wood and covering it up with dampened dirt. The wood was then set on fire in the oxygen scarce environment so it would burn slowly. The process was done by a specialized worker called a charcoal-burner and was even mentioned in a Greek play called “The Archarnians” in 425 BC [12].

Although this may sound like a very straightforward technique the charcoal-burner was a very skilled operator and generally passed the art down from generation to generation. The technique remains mostly unchanged till this day in most of the developing world due to its simplicity and lack of expensive equipment.

In the modern world there has been some development in the field of charcoal production. For instance there is the Missouri kiln that employs much control over the airflow and temperatures but unfortunately require an operating cycle of 7-30 days and has a ychar on the order of 20-30% [13]. At companies like Kingsford the biggest change is that the charcoal is produced in a continuous manner.

The feedstock is sent through large steel drums which are externally heated and can produce a finished product in under 24 hours [14]. This form of charcoal is more expensive to manufacture but since the charcoal is sold at a premium for cooking food the business model remains profitable.

2.5 Advantage of Flash CarbonizationTM

All Thermochemical equilibrium is the ratio at which any mixture of elements stabilizes at within a given pressure and temperature. A convenient program called STANJAN can be used to calculate the ratio between elements and compounds. More simply put if you feed this program the elemental makeup of any feed, along with its temperature and pressure, it will calculate the maximum possible pure carbon yield a biomass can produce [15]. In most conventional methods of charcoal production the fixed carbon is well below the maximum. This inefficiency leads to higher levels of deforestation in many parts of the world [16] a big problem associated with global warming.

As seen in many experiments the Flash CarbonizationTM process is able to achieve near maximum theoretical fixed carbon yield. One theory states that the tarry vapors that are produced in pyrolysis recombine with the surface forming a secondary charcoal [13]. This is due to the fact that the vessel is at elevated pressure. Regardless of the reason the results speak for themselves with fixed carbon yield’s ranging from 25-30%.

The fact that Flash CarbonizationTM is more efficient is not its most attractive quality. The fact that the process can be completed in under an hour is really where it sticks out as being a truly revolutionary idea. Given that the feedstock is not in short supply, and in many cases it is a waste that is being used, the biggest expense is labor cost. It can be observed that high combustion rate of the secondary vapors at elevated pressure make the oxygen unable to reach the surface of the carbon due limited mass-transfer. This has the result of producing charcoal at an unparalleled speed.

Chapter 3:

Lab Scale Reactor

3.1 Reactor Description

3.1.1 Pressure Vessel and Canister

Figure 3.1 Schematic of Lab Scale Reactor.

The reactor is a very simple set up as you can see from figure 3.1. It consists of an outer steel pipe with blind flanges on the top and bottom and is referred to as the “vessel”. The point of the vessel is to house

10 charcoal production under elevated pressure. The vessel is rated for a maximum pressure of 6.10 MPa

(870 psig). Since the vessel operates at elevated temperature and pressure it was important to be designed to code and inspected by the state boiler inspector.

The Canister is used to house a bed of feedstock and is placed inside the vessel for every run. It is a 97.5 cm long tube with an inner diameter of 9.5 cm. The canister has an airtight lid with a hose running to it from a primary air source. This is to ensure a precise amount of air travels from the top of the feedstock bed to the bottom. At the bottom of the canister rests a mesh to prevent any biomass from falling out while letting air and heat pass through. The canister is lowered onto flanges and rests directly above an electric heater.

3.1.2 Primary air source

A reservoir of pressurized air known as the “air cart” is used to supply the feed with air while the experiment is in progress. It consists of 4 standard scuba tanks pressurized to 3000 PSI. A pressure transducer measuring pressure inside the tanks is electrically connected to a digital display and a computer. The display is used by operators while the computer logs the pressure throughout the experiment. This air supply runs through a pressure regulator to ensure a constant pressure being supplied to the vessel. Then a micrometer valve is placed in line so an operator can control the precise amount of air flow throughout the experiment. Next piping connects into the top of the pressure vessel to flow directly into the bed of biomass.

Since weight is not directly measured on this air cart an attempt was made to form a simple equation relating pressure and mass. I performed an experiment where the air cart was lifted onto a scale and weighed before and after pressure was released then once temperatures were allowed to equilibrate a second pressure reading was performed. After running multiple tests it was concluded that approximately 3.3±0.4 grams of air is released for every PSI decrease in the tanks. The level of

11 uncertainty was thought to be caused by the pressure transducers inaccuracy at high pressure. At pressures below 400 PSI a much more accurate pressure gauge was able to be used and a value of

3.6±0.1 grams/PSI was discovered.

3.1.3 Electric Heater

To initiate a flame in the bed an electric heater (ARi BXX-19B-45-5T) is placed 3 cm below the bottom of the canister. This heater originally comes as a rod and is bent by hand into a spiral shape to fit into the vessel. The heater is generally only required for 6 minutes or less to initiate the flame. Once the flame is ignited the heater is turned off for the rest of the experiment.

3.1.4 Exhaust

Since the reactor reaches high temperatures and elevated pressure plumbing is a very serious safety issue. The primary method of controlling pressure is a line that runs from the bottom of the vessel out to a HL31 1/2 NPT globe valve. The globe valve was chosen because its ability to easily control back pressure. In case there is ever a problem with the globe valve an automatic pressure release valve is hooked up in parallel. This second line consists of an actuator, ball valve, and controller. When pressure reaches a preprogrammed point (usually 200PSI) the controller signals the actuator to open the ball valve until the pressure is again bellow the desired pressure. A third line venting from the top of the vessel has a burst diaphragm in it rated to 387 PSI. This safety feature is required by the state code and adds another level of safety to our vessel.

All lines vent to a fume hood in the lab which in turn vents to the outside. A small portion of the exhaust stream is diverted to an oxygen sensor and is displayed to the operators running the experiment. The oxygen sensor is able to measure oxygen levels to an accuracy of 0.1%. The total distance of the exhaust piping is roughly a few meters and can cause a delay on oxygen readings. This delay varies slightly but is generally assumed to be less than 30 seconds.

3.1.5 Common Feedstocks

The biggest variable in the Flash CarbonizationTM process is the feedstock material. As a result of the differences in chemical makeup and physical structure the charcoal will have very different properties based on the feedstock being used. It will also have a great affect on exhaust among other things. A couple of the common feedstocks that we have worked with include corncob, all forms of wood from blocks to sawdust and macadamia nut shells to name a few.

The corncob we use has been shown to ignite very easily and maintain a flame throughout the experiment making life very easy for the operator to ensure complete carbonization. Some feedstocks such as sewage sludge have shown difficulty when trying to ignite and will drop below ignition temperatures during an experiment. Since corncob burns so reliably it will sometimes be used as a bottom layer to ensure complete combustion of more difficult fuels. Wood is somewhere in between in its ignition properties; it generally ignites and burns continuously but will occasionally die out before complete carbonization is achieved. Sewage sludge is also high in heavy metals which can pose considerable health risks and is always handled with extra caution.

3.1.6 LabVIEW

While running an experiment it is imperative to know temperatures and pressure in a real time setting.

To accomplish this a combination of thermocouples and pressure transducers are rigged to the experiment in key places of interest. To interpret this data in real time and display it in a meaningful way a program called LabVIEW is used. A program I have written custom tailored to our specific need is being used and can been seen in figure 3.2. A graph displays temperatures of the last few minutes. This is the most important feature because it lets the user easily judge where the temperature is going and how airflow should be adjusted. The program also has a graph of the pressure and a display of total air consumption.

Figure 3.2 Screen shot of LabVIEW program.

3.2 Flash Carbonization Experiment Overview

3.2.1 Preparation for Experiment

When preparing a run it is important to pressurize the air cart to 3000 PSI using the air compressor.

Then one must pack the canister with the feedstock and make a careful measurement of how much feed was loaded. This measurement is used as an estimate to determine how much air should be delivered during the experiment. Due to the complexity of the many variables affecting carbonization for instance temperature throughout experiment, biomass being used, O2 consumption, etc. an exact amount of air delivery has not been developed. Previous work has developed a general rule of thumb that for every gram of feedstock 3.2 PSI of pressure is to be delivered from the air cart. This calculated pressure is later

14 subtracted from the starting pressure and used as an indicator for when the experiment is near completion. The canister’s lid is then attached and is then loaded into the vessel.

A gasket is then placed in between the vessel and the vessel’s lid to ensure an airtight seal. The lid for the vessel is secured with twelve 1 inch bolts and hand tightened with a wrench. All exhaust lines are attached and are double checked for leaks. The thermocouples and pressure transducers are then attached to the computer. Then the vessel is pumped to the desired pressure and the experiment is ready to begin.

3.2.2 Experiment Procedure

The run begins with powering on the heater for 6 minutes. In this time the pressure builds on the order of 20 to 30 PSI. The heater is then turned off and the globe valve is manually cracked opened to reduce the pressure to its original setting. At this time an operator opens the flow of air into the top of the canister ensuring the flame propagates up the bed. The pressure is maintained at its original point by constant adjustment of the globe valve. If temperatures become higher or lower than desired the airflow is adjusted to correct any problems. During the run O2 levels are logged into the LabVIEW program by a different operator. A third operator watches the exhaust while controlling the delivery of air. Once the desired change in pressure is approached the operator who watches the exhaust makes a decision when to finish delivering air. The decision is based on a couple factors most important are the amount steam visible in the exhaust (generally sparse steam correlates with complete carbonization), the temperature exiting the vessel, and the consumption of O2 throughout the experiment.

Once the decision to finish the run has been made the primary air is shut off while the globe valve is opened up so the vessel can exhausts its remaining contents and return to atmospheric pressure. Due to the fact that the vessel is hot the reactor is allowed to cool overnight and the contents

15 examined in the morning. The experiment will generally last 30-50 minutes all depending on what type of feedstock is run and the pressure it was run at.

3.2.3 Examination of Results

Once the reactor has cooled down it is then opened up and the canister removed. The contents of the canister are then laid out on a tarp in the same fashion it was in the canister. This allows an observer to see if any part of the bed was not fully carbonized and if so which part. The charcoal is allowed one day to equilibrate with the moisture in the lab this ensures that when a proximate analysis is performed the test represents the entire samples moisture content. After this time the charcoal is split into 3 to 4 sections based on its location in the canister with corncob being in its own section if it was used as a base. Then each section is weighed and has a proximate analysis run on it. A graph is made up of temperatures, pressures, airflows and O2 consumptions and is used for further analysis.

3.3 Operational Problems

3.3.1 Pressure Control

When tarry vapors leave the vessel under high temperature they tend to condense on the cooler plumbing which can lead to clogging in the pipes or valves. This will result in the inability to relieve the pressure with the globe valve. Generally it is not a safety issue due to the second and third emergency release vents but it will prevent a run from continuing and force the experiment to be wasted. This has been managed with proper cleaning of the pipes on a more frequent routine. This problem has not been observed with the demo reactor likely due to the fact that at larger diameters tars get flushed out naturally.

These tarry liquids can also prohibit the globe valve from sealing properly not allowing the vessel to hold pressure. This is not nearly as large of a problem because it is detected before the run has started and can be fixed by swapping out the globe valve for a new one.

3.3.2 Incomplete Carbonization

One of the more difficult things to predict is deciding when the carbonization process is complete. If you let the experiment run too long the charcoal itself begins to burn and if you don’t let it run long enough generally the top of the bed does not become carbonized. Due to the complexity of this decision it is more of an art form than a science. Through experience one learns the signs and complete carbonization is easier to achieve although incomplete runs do happen they are not a common occurrence. There have been some attempts to make the decision easier which include soaking the top layer of feedstock in water. This serves as a signal to an operator that when large amounts of steam come from the exhaust it means the run is nearly complete.

Another occurrence of incomplete carbonization is when the flame will jump from the bottom of the bed to the top of the bed without carbonizing the middle section. This does not happen as often and is thought to be caused by loosely packing of the bed and allowing the flames to propagate through openings in the biomass.

Chapter 4:

Charcoal and Fixed Carbon Yield

4.1 Parameters That Affect Fixed Carbon Yield

In any commercial process it is important to maximize the profit one can make. There are two ways to do this: minimize processing costs and maximize product output. Since carbon is the true goal of

TM charcoal in the Flash Carbonization process, maximizing Yfc will achieve the highest output of product.

Many different factors have been explored in past research but only three specific metrics will be explored in this thesis. These include feedstock selection, pressure which the Flash CarbonizationTM process occurs at and average particle size for the feedstock.

4.1.1 Feedstock

It is important to understand the feedstock being used in charcoal production especially when determining what the final product will be used for. For instance, sugar has been measured to contain less than .01 ash which is the limit of accuracy our technique can reliably test for. This will most likely result in a charcoal with virtually no ash in it. Understanding the feedstock also gives an attainable maximum fixed carbon yield. This maximum fixed carbon yield is an important metric to compare the final product against.

An elemental analysis measures a sample’s carbon, nitrogen, oxygen, hydrogen, sulfur and ash content and reports them on a per weight basis. In Table 4.1 the elemental analysis results are presented as determined by Huffman Laboratories Inc. and Hazen Research Inc. It is obvious that the results from the different labs are not identical as was expected and had been shown in previous research. It should be noted that moisture content can vary radically due to the conditions labs keep

samples in before testing. Moisture content is not a very significant aspect of charcoal so it is not heavily

monitored. Due to precision limitations and variations in even homogenized samples, labs can report a

wide range of values for elemental composition. For example, the C content in Cowboy oak wood fine

was 51.63% reported by Hazen as opposed to 49.22% by Huffman. Likewise Huffman measured 43.97%

for the O content of Dow Corning oak wood blocks while Hazen measured 40.55%.

MCa ultimate analysisb (wt %)

Feed (wt %) C H O N S ash yfc sweet gum (Hazen)c 6.67 49.93 6.01 42.24 0.09 0.03 1.70 35.3 sweet gum (Huffman) 30.88 47.89 5.91 44.31 0.12 0.03 2.35 33.0 white oak (Hazen)c 10.06 50.69 6.02 42.74 0.06 <0.01 0.49 35.5 white oak (Huffman) 7.85 48.78 5.97 44.42 0.07 0.01 0.76 33.5 red oak (Hazen)c 9.59 51.02 6.03 42.49 0.06 <0.01 0.40 35.8 red oak (Huffman) 8.10 49.05 5.92 44.58 0.06 0.01 0.46 33.7 Cowboy oak 2003 (Huffman) 8.60 50.81 6.00 43.53 0.11 0.02 0.43 35.2 Cowboy oak sawdust 2003 (Huffman) 9.12 50.89 5.83 42.31 0.17 0.06 1.12 36.2 Cowboy oak 2000 (Huffman) 5.26 50.13 5.98 44.76 0.08 0.03 0.19 34.2 Dow Corning oak blocks (Hazen)c 12.83 49.66 5.95 40.55 0.35 0.04 3.45 36.0 Dow Corning oak blocks (Huffman) 5.38 48.56 5.73 43.97 0.12 0.03 2.37 34.0 Dow Corning oak coarse (Hazen)c 11.30 50.44 5.95 41.41 0.21 0.02 1.97 36.1 Dow Corning oak coarse (Huffman) 6.57 48.62 5.89 43.82 0.13 0.01 2.45 33.8 Dow Corning oak fine (Hazen)c 11.78 49.83 5.87 43.73 0.21 <0.01 0.36 34.7 Dow Corning oak fine (Huffman) 6.59 49.04 5.88 44.17 0.11 0.02 1.48 33.9 Cowboy oak coarse (Hazen)c 7.72 49.76 5.86 44.04 0.14 <0.01 0.20 34.5 Cowboy oak coarse (Huffman) 6.10 49.06 5.98 44.80 0.09 0.01 0.81 33.5 Cowboy oak fine (Hazen)c 8.29 51.63 6.16 41.49 0.14 <0.01 0.58 36.5 Cowboy oak fine (Huffman) 6.33 49.22 6.08 44.32 0.09 0.01 0.84 33.6 Laurel wood (Hazen)c 33.14 50.35 5.82 41.49 0.16 0.03 2.15 36.3 Laurel wood (Huffman) 31.07 48.94 5.90 43.05 0.20 0.03 2.47 34.4 a Table 4.1 Ultimate Analyses of Oak and Sweet Gum Woods and the Calculated Theoretical Fixed-Carbon Yields yfC. Moisture content on a wet mass basis. bDry mass basis. cOxygen content calculated by difference.

These elemental analyses will end up playing a vital role in the calculations for fixed carbon

yields which is why 2 separate labs were chosen to perform the tests. One thing should be noted that

Huffman does a direct measurement of oxygen and will have a total percentage that may not add up to

100%. While Hazen measures all other elements of the sample and subtracts the total from 100% to discover oxygen content, which is why Hazen’s results always sum to 100%.

One theory we had was that material of the same feed at different sizes might contain more or less ash due to contamination from grinding. The Dow Corning coarse material when compared to the fine material has more ash according to both Hazen and Huffman while Hazen shows the fine Cowboy sawdust has slightly more ash when compared to the coarse material but Huffman reports approximately the same. It should be noted that grinding can produce a lot of dust and depending on the makeup of the dust leaving it could affect the overall ash content.

Even though deciding which feedstock will best fit an application it is not always practical due to what is available. On Oahu we are limited to crop waste that is grown on the island such as corncob and macadamia nut shells. The summer I spent researching in Norway we focused on wood because it was such an abundant fuel source. This is why feedstock has the least flexibility when compared to pressure or particle size.

4.1.2 Correction from wet to dry

Both Hazen and Huffman generally report results of the samples after they have been dried of all moisture. This is because moisture content can change very easily as discussed previously making results on a dry basis more useful when running calculations. Unfortunately Huffman performed an analysis without first drying the samples and a correction needed to be made in order to use the results.

Moisture Feed stock C H O N S Ash Sum Content(MC) Cowboy oak 8.6 46.44 6.45 47.42 0.1 0.02 0.39 100.82 wood Cowboy oak 9.12 46.25 6.32 46.55 0.15 0.05 1.02 100.34 wood sawdust Table 4.2 Huffman’s results on a wet basis as a percentage of total mass.

Each element needed to be corrected by the appropriate equation as represented in equations

4.1 through 4.6

C(dry) = C(wet)/(1-MC/100) (4.1)

H(dry)=((H(wet)-(MC*2.01588/18.01528))/(100-MC))*100 (4.2)

O(dry)=((O(wet)-(MC*15.9994/18.01528))/(100-MC))*100 (4.3)

N (dry)=N (wet)/(1-MC/100) (4.4)

S (dry)=S (wet)/(1-MC/100) (4.5)

Ash (dry)=Ash (wet)/(1-MC/100) (4.6)

Where X (dry) means percent of element X in a dried sample and X (wet) represents the percent

of element X Huffman reported.

Feed stock C H O N S Ash Sum Cowboy oak wood 50.81 6.00 43.53 0.11 0.02 0.43 100.90 Cowboy oak wood 50.89 5.83 42.31 0.17 0.06 1.12 100.37 sawdust Table 4.3 New ultimate analysis corrected for moisture content.

An analysis of oak wood blocks has been completed by Huffman in which they reported

both on a dry basis and wet basis. The previous equations have been applied to these results to

demonstrate the validity of the equations as demonstrated in table 4.4.

MC C H O N S Ash Huffman reported 5.38 45.95 6.02 46.38 0.11 0.03 2.24 wet basis Calculated dry basis 0 48.56 5.73 43.97 0.12 0.03 2.37 Huffman reported 0 48.56 5.73 43.97 0.12 0.03 2.37 dry basis

Table 4.4 Example calculations run on previous results.

4.1.3 Particle size

Ideally all feedstocks would be received at an optimal size. Unfortunately in the real world sometimes a fuel needs to be processed to produce a better charcoal. For many moist feeds they are dried before they are ready to be used and with oak wood it may need to be ground or split to achieve proper particle size. The size of particles in the feed has been shown to heavily contributing to ychar as discussed by Antal and Varhegyi in previous papers [17] [18] [19] [20]. It is with this past work that further research has been done investigating the affects particle size can have.

Various sized blocks of Sweet gum and red oak wood were carbonized in an inert atmosphere

(nitrogen) at 0.1 MPa. The blocks were first placed in crucibles then put into an oven and fed nitrogen for 30 min to guarantee all oxygen was evacuated from the oven. The temperature was then raised to

105˚C and held for 30 minutes then raised to 950 at 10˚C/minute. The charcoal is then allowed to cool while remaining in the nitrogen atmosphere. This procedure can be referred to as the muffle furnace carbonization process. We were fortunate enough to collaborate our research with Dr. Liang Wang, Dr.

Øyvind Skreiberg, and Dr. Morten Gronli at SINTEF energy research in Trondheim, Norway on this research. They were able to perform supplementary experiments of which the results are displayed in

Table 4.5, and figures 4.1-4.3

proximate analysisa (wt %) y y particle size char fC VM fC ash (wt %) (wt %) red oak 14 mm cube 1.61 97.14 1.26 23.91 23.26 30 mm cube 2.00 96.38 1.62 23.74 22.92

30 mm x 20 mm x 75 mm block 3.89 94.73 1.38 23.45 22.25 sweet gum 14 mm cube 2.76 91.95 5.29 23.52 21.80 30 mm cube 4.38 90.09 5.53 24.36 22.13 30 mm x 20 mm x 75 mm block 3.64 89.76 6.60 23.88 21.61 Table 4.5 Charcoal produced in nitrogen atmosphere.

The red oak wood roughly kept its ychar constant on all three sizes with a slight decrease from

23.91% to 23.45% as the dimensions increased from a 14 mm cube to a 30 mm x 20 mm x 75 mm block.

The red oak wood’s yfc followed the same trend of a slight decrease from 23.26% to 22.15%.

Table 4.5 shows sweet gum’s results had very similar results when compared to red oak. When choosing particle sizes between 14 mm and 30 mm it makes little to no difference to the ychar and yfc.

These less than 1% differences can be assumed to be natural fluctuations in the carbonization process.

20 18 16

14 red oak Char Yield Yield Char(wt%) 12 sweet gum 10

Particle Size (mm)

Figure 4.1 Graph of red oak and sweet gum particle size vs char yield.

Another experiment performed by Liang Wang tested much smaller particle sizes to see if there would be a significant effect on ychar, the samples were not tested for yfc. In figure 4.1 the graph displays the results of 10 mg samples of red oak wood and sweet gum using the muffle furnace carbonization technique. The samples were of different sizes varying from .063 mm to 7 mm. The graph shows that when particle size is between .063 mm and .355 mm, for both red oak and sweet gum, there is a slight increase in charcoal yield but not a significant amount. Once the particle size increases past that the charcoal yield starts to dramatically increase. The largest particles are 7mm and shows there is a major

23 improvement in charcoal yield increasing from approximately 15% to 22% when compared to .063mm particles.

Work was also done using the Flash CarbonizationTM process Table 4.3 shows these results of experiments performed on oak and laurel woods. It should be noted that the Cowboy oak wood sawdust had been in storage for more than a decade. There were no signs of changes in the wood mostly due to the fact that it was kept inside a dry air conditioned building. The wood did not contain any bugs or mold which has been observed on other feedstocks and leads us to believe the wood was nearly identical to its original condition. The Dow Corning saw dust was received and used for experiments within a few months of receiving it.

The sawdust was received as one large batch. It was then sifted into two different sizes of particles. Coarse refers to sawdust that was not able to pass through 8 mesh screen with openings 2.38 mm large. Fine sawdust was sifted through the 8 mesh screen but unable to pass through the 30 mesh screen with openings .599 mm. The material able to pass through the 30 mesh screen was not used in any experiments because there was not enough of it to run an experiment and it didn’t seem necessary since it had already been shown that very fine particle feedstock did not produce favorable charcoal.

If you compare Table 4.6’s results of yfc and ychar both metrics increase dramatically with increased particle size. For Cowboy oak wood the ychar increases by 10.18% and the yfc increases by

5.56% when increasing from fine to coarse sawdust. The Dow Corning oak woods ychar and yfc nearly doubles when comparing the fine sawdust with the blocks from 18.13% 16.67% to 29.99% 26.15%.

These results suggest that the most efficient way to carbonize this oak wood is to leave it in larger blocks and not much grinding or chopping is required to produce a better product.

pressure proximate analysis (wt %) ychar yfC particle MPa VM fC ash (wt %) (wt %) feed sizea Cowboy oak sawdust 120217 2.17 19.80 78.43 1.77 35.04 27.59 coarse

Cowboy oak sawdust 120305 1.14 6.29 89.58 4.13 17.89 16.06 fine Cowboy oak sawdust 120313 2.17 8.93 88.40 2.67 24.86 22.03 fine Dow Corning oak sawdust 120323 1.14 10.26 83.80 5.94 26.82 22.91 coarse Dow Corning oak sawdust 120327 1.14 4.92 90.66 4.42 18.13 16.67 fine Dow Corning oak 120713 1.14 12.57 86.41 1.02 29.99 26.15 blocks Laurel wood 120905 1.14 9.08 85.90 5.03 30.75 27.07 blocks Table 4.6 Charcoal and Fixed-Carbon Yields Realized at Elevated Pressure in the FC Reactor. a coarse = sawdust smaller than 8 mesh but larger than 30 mesh, fine = smaller than 30 mesh, blocks = roughly 1"x1"x4" One experiment that may have been useful would have been one using large logs nearly the diameter of the canister 9.5 cm. That experiment may determine if increased particle size always does increase yfc. Regardless these results are very promising for future charcoal production. Very little processing will need to be done to the wood in order to provide a superior product. This is especially beneficial to economics of charcoal production as extra time generally correlates with higher expenses.

4.1.4 Pressure

The largest difference between the Flash CarbonizationTM process and traditional carbonization techniques is the fact that it operates at elevated pressure. It is believed that the pressure is the cause of the higher charcoal yields and fast carbonization reactions. It should then be asked does further elevating of pressure benefit the yfc or is there a maximum pressure at which further elevation has little to no affect on yields.

First let’s look at fine Cowboy and Dow Corning oak sawdust in Table 4.6 carbonized at 1.14

MPa. These yfc values of the two runs are 16.01% and 16.67% which is very similar to the results of red oak and sweet gum carbonized at atmospheric pressure. We believe these woods behave equally when being carbonized and therefore can be compared.

Next we can relate the coarse Dow Corning oak sawdust in Table 4.6 to the red oak and sweet gum results in Table 4.5. The coarse Dow Corning oak sawdust has much smaller particle size than all the samples in Table 4.5 but has nearly identical yfc. The Dow Corning oak blocks demonstrate a yfc of 26.15% which is greater than any of the experiments run at 0.1 MPa.

Also we can compare the effects of further increasing the pressure and the effects it will have on the charcoal product. Take the fine Cowboy oak wood in Table 4.6 carbonized at different pressures. The fine Cowboy oak sawdust carbonized at 1.14 MPa had a charcoal yield of 17.89% and a fixed carbon yield of 16.06%. When the pressure was nearly doubled to 2.17 MPa both charcoal yield and fixed carbon yield increased to 24.86% and 22.03% respectively. It should be noted that experiments were conducted only at 2 different pressures and varying the pressure less drastically between experiments may have shown a more complete picture of how pressure affects charcoal.

Figure 4.2 SEM micrographs of red oak charcoal sample produced in the muffle furnace at 0.1 MPa.

Figure 4.3 SEM micrographs of Cowboy oak charcoal sample produced in the FC reactor at 2.17 MPa.

The structure of the charcoal can also be important to charcoal uses which is why both the red oak charcoal from Table 4.5 and the Cowboy oak wood carbonized at 2.17 MPa are displayed in figure

4.2 and 4.3 respectively. The charcoal was analyzed by Liang Wang with a SEM micrograph at NTNU. The fibrous structure of the charcoal remained evident in figure 4.2 and resembled its feedstock structure of the red oak. The Cowboy oak wood on the other hand observed charcoal that passed through a molten state during carbonization at elevated pressure. These observations at elevated pressure are rare and have only been observed by few other studies. Cetin described pine sawdust chars which experienced melting and swelling at elevated pressures and high heating rates [21]. Joyce made the observation that bagasse chars formed at high pressure in an inert atmosphere appeared to have passed through a molten/swollen state prior to resolidification [22]. Although figure 4.3 shows evidence of a swollen state, Flash CarbonizationTM experiments have never demonstrated an increase in bed size and in fact the opposite is true that the bed has always decreased in its original size.

Although elevating the pressure has many benefits it is important to understand the drawbacks also associated with elevated pressure. During a demo reactor experiment on January 9th, 2013 the ignition process slowly increased the pressure to 1.53 MPa from 1.16 MPa over the course of 5 minutes.

Then suddenly within 4 seconds the pressure spiked to 3.80 MPa and blew the burst diaphragm.

Working at these elevated pressures can be dangerous and should be avoided if not necessary. A more detailed description of the event is included in appendix A.

4.2 Thermochemical Equilibrium Calculations

4.2.1 Thermochemical Equilibrium Explained

Chemical equilibrium as defined by the Encyclopedia Britannica is “a condition in the course of a reversible chemical reaction in which no net change in the amounts of reactants and products occurs. A reversible chemical reaction is one in which the products, as soon as they are formed, react to produce

27 the original reactants. At equilibrium, the two opposing reactions go on at equal rates, or velocities, hence there is no net change in the amounts of substances involved. At this point the reaction may be considered to be completed; i.e., for some specified reaction condition, the maximum conversion of reactants to products has been attained” [23]. A Thermochemical equilibrium is when a reaction is in chemical equilibrium at a specified temperature and pressure.

In more mathematical terms thermochemical equilibrium is when the Gibbs free energy of a system reaches its minimum. Once a thermochemical equilibrium calculation is solved it is possible to know the maximum amount of any product one can expect to get from reactants. This is very important to our research because it gives us a maximum goal we could hope to achieve and then we compare this maximum to what we achieve.

4.2.2 Example Calculations

Using an example from Thermodynamics an Engineering Approach [24] of burning carbon monoxide

(CO) with oxygen (O2) it becomes a lot clearer how to solve a thermochemical equilibrium problem.

Carbon and oxygen can form many different compounds such as carbon suboxide (C3O2) or mellitic anhydride (C12O9) but these are not expected to be produced in substantial quantities and can be ignored for this example. An example of CO and O2 combining to create CO2 is presented below.

Problem statement: A mixture of 2 kmol of CO and 3 kmol of O2 is heated to 2600 K at a pressure of 3 atm. Determine the equilibrium composition, assuming the mixture consists of CO2, CO, and O2.

Analysis:

Stoichiometric: CO+1/2O2 CO2 making ѵCO=1, ѵO2=1/2, and ѵCO2=1

Actual: 2CO + 3O2→XCO2 + YCO + ZO2 where X, Y, and Z are the molar balances.

C balance: 2 = X + Y or Y = 2 - X

O balance: 8 = 2X + Y + 2Z or Z = 3 – X/2

Now assuming ideal gas behavior the equilibrium constant relation is displayed in equation 4.7.

4.7

Where Nx is the number of moles of x, P is the pressure in atmospheres, and Kp is the equilibrium constant and can be found in thermodynamic tables. At 2600K Kp = 16.461 [24]. With plugging values in for the variables equation 4.7 becomes equation 4.8

4.8

Solving for the variables we get

X = 1.906

Y = 2 – x = 0.094

Z = 3 – X/2 = 2.047

Finally we are left with 1.906 kmol of CO2, 0.094 kmol of CO, and 2.047 kmol of O2. Which means if an experiment was set up with identical conditions after enough time we would expect the same results. In this simplified case it is easy to see the process required to solve an equation. The problem becomes exponentially more time intensive when more reactants and products are add to the equation.

4.2.3 STANJAN Calculations Run on Feedstock

In our research we have a total of 4 reactants and 9 products simultaneously being calculated by chemical equilibrium. This sheer number of variables makes it impractical to run hand calculations to solve for a solution therefore the computer program STANJAN is used to aid us in our research. STANJAN is a chemical equilibrium solver written by Professor William Reynolds of Stanford University (the

"STAN") based on thermodynamic data from the JANNAF tables (the "JAN"). It will calculate the equilibrium concentrations, pressure, temperature, enthalpy, etc. for any set of reactants for which property data are available. The user may constrain the equilibrium by specifying some of the end thermodynamic conditions (P and T, P and H, U and V, etc.) and by limiting the species present in the products.

In order to run a STANJAN calculation on a feedstock first we need to know the elemental makeup of the feedstock. The elemental analyses that we used are in Table 4.1. The values must first be converted to molar fraction by dividing its mass fraction by its molar weight. As in figure 4.4 below the carbon content of Cowboy oak wood 2000 is 50.13 and its population is 4.1738 which is what the program uses to calculate thermochemical equilibrium. Next a pressure and temperature is decided upon. All simulations were run at 1.01 MPa (10 atm) and 673 K a common temperature witnessed in

Flash CarbonizationTM experiments. The last decision we made was what the products would be. We decided H2, H2O, CH4, CO, CO2, NO, NO2, N2, O2, and C would be the most prominent. Figure 4.4 shows the results of STANJAN simulation run on Cowboy oak wood 2000 analyzed from Huffman. These analysis were run on all the samples in Table 4.1 and their STANJAN simulation results can be found in appendix B. Everything that is manually inputted is bolded for clarity.

3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 1; Gas species: CH4 16.04300 -17.895 53.086 4.086 CO 28.01054 -26.420 52.995 2.673 CO2 44.00995 -94.054 59.447 3.927 H2 2.01600 .000 36.889 2.618 H2O 18.01601 -57.798 51.899 3.149 NO 30.00800 21.580 56.262 2.736 NO2 46.00800 7.910 65.489 3.815 N2 28.01340 .000 51.518 2.655 O2 31.99879 .000 54.988 2.776

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700 phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.17380000E+00 -1.0513 H 5.93370000E+00 -8.7937 O 2.79760000E+00 -47.7450 N 5.70000000E-03 -14.2886

Products at T = 673.00 K P = 1.000E+01 atmospheres species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.584 kg/kmol CH4 .22574E+00 .11421E+00 .10554E+00 6.64145E-01 CO .12643E-02 .63964E-03 .10321E-02 3.71965E-03 CO2 .21508E+00 .10882E+00 .27586E+00 6.32784E-01 H2 .37473E-01 .18959E-01 .22016E-02 1.10248E-01 H2O .51947E+00 .26281E+00 .27274E+00 1.52831E+00 NO .28765E-23 .14553E-23 .25155E-23 8.46286E-24 NO2 .67402E-38 .34100E-38 .90373E-38 1.98301E-38 N2 .96871E-03 .49009E-03 .79084E-03 2.85000E-03 O2 .44204E-31 .22364E-31 .41222E-31 1.30050E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49408E+00 .34183E+00 2.87315E+00

phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.360 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6106E-01 m**3/kg U =-6.2104E+06 J/kg H =-6.0472E+06 J/kg S = 6.6806E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC FIGURE 4.4 Results of STANJAN simulation.

4.2.4 Comparison of Theoretical Yield vs Achieved Yield

Because different feedstocks have different potentials of carbonization it is more appropriate to compare different carbonization experiments by their percentage of total possible carbon. Figure 4.5 is a parity plot prepared by Liang Wang comparing theoretical fixed carbon yields based on STANJAN calculations vs. experimental values from Table 4.1, 5, and 6.

Figure 4.5 Parity plot of multiple charcoals theoretical yfc vs experimental yfc.

The worst results were as low as 35% of theoretical yield and these were from the experiments run in the muffle furnace in an open crucible. The best results we witnessed were from the Cowboy oak wood at 2.17 MPa the high pressure and larger particle size just confirms our hypothesis that these conditions induce higher yfc.

Chapter 5:

Conclusion

5.1 Future work

There were many interesting things learned from this research yet still many things yet to be discovered.

For starters there will always be more feedstocks to test out each with its own unique properties. I was able to do the preliminary experiments on carbonizing sugar and found nearly zero percent ash and volatile matter on these samples which would make it an ideal charcoal for silicon production. A fellow lab mate of mine is researching sewage sludge as a feedstock and if it could be used as a soil amendment. This would serve both purposes of getting rid of the sewage sludge that waste facilities produce and could possibly turn sterile soil fertile.

As demonstrated previously in this paper increased pressure shows an increase in yfc but it is not fully understood to what extent this is true. It would not be possible for yfc to increase indefinitely since yfc cannot be higher than 100%. In order to fully understand this relationship it may be useful to continue further experimentation where pressure is increased until yfc levels off or decreases.

5.2 Conclusion

After obtaining elemental analyses we were able to calculate a theoretical yfc this served as a maximum achievable goal for our charcoal. After calculating this value we were able to compare against experimental charcoals formed under varying pressure, particle size, and feedstocks. What this showed was that when particle size increases it also increases yfc up until a certain point. Increasing pressure increases yfc with no limit found. Different feedstocks of similar woods had little affect on the charcoal.

This research will provide valuable information to further work with the Flash CarbonizationTM technique.

Appendix A:

130109 Demo Reactor Run Report

Set up: The vessel was loaded with 34.96 lbs of corn cob and 21.42 lbs of sawdust/woodchips. The CAB was lit and brought to a temperature of 650°C. At the same time the reactor was brought to a pressure of 153 PSI. Maider was set up to take gas samples Greg controlled the heater and the secondary air Sam Monitored all temperatures and pressure with the computer and Lloyd controlled the primary air.

Test Run: The test began with plugging in the heater and was planned to heat for 6 minutes. The pressure increased very steadily for the first 5 minutes. It reached 207 PSI then the pressure skyrocketed up to 536.1 PSI and at some point in between it blew the burst diaphragm releasing the pressure. The pressure took a total of 4 seconds to spike and took approximately 8 seconds to drop down in pressure again. The max temperature recorded at the exit of the reactor was approximately 450°C. The Lab View program is set up to record readings every 5 seconds and did not get the details of the spike. Fortunately there is a continuous display of the pressure onscreen at all times and we were able to take screen shots of this graph as seen below.

Figure A.1 Entire demo reactor experiment pressure graph.

Figure A.2 Demo reactor 4 second pressure spike pressure graph.

Figure A.3 Demo reactor 18 second pressure spike pressure graph.

Figure A.4 Demo reactor 6 second pressure spike pressure graph.

Figure A.5 Demo reactor pressure peak pressure graph. Results: After inspecting the charcoal all of it appeared to have its outer skin burned but the core was still raw feed. There was damage done to the reactor what appeared to be a strong force broke the bottom mesh which was welded to the canister off and pushed the heater down against the bottom of the vessel. We will take extra precautions and operate at lower pressures until we feel comfortable with running at 150 PSI again.

Analyzing the results: The total volume of the reactor vessel was calculated to be 2.16575m3 since the canister and feedstock take up volume a reasonable assumption we will use for the volume of air is 2m3. The original pressure was 154 psi and the starting temperature was 25°C. In order to achieve a pressure of 536 PSI there would need to be a temperature of 765°C. The observed exit temperature maxed out at 450°C. Even though it could have been hotter inside the canister at the time of sudden pressure increase this is not known. Another idea for explaining the sudden pressure rise is the formation of gas products. One source for gas production would be the boiling of water in the feed stock. The moisture content was 10.37% for corn cob and 10.12% for sawdust making the total available amount of water to be 5.787 lbs. This would add .146 kmol of steam to .94 kmol of air that is already in the tank. Using ideal gas

36 laws the pressure with the added steam at 450°C would be 473 PSI. A third thing that could have contributed to the pressure rise was the burning of the feed. Assuming most of it was cellulose with a chemical balance of (C6H10O5)+6O2->6CO2+5H2O and considering .227 kg of cellulose was burned that gives a maximum of 1.4 moles added to the system. This is such a small amount it would barely be noticeable.

To find a somewhat good approximation of the temperature inside the canister we can try to find how much energy is released when burning .227 kg of cellulose. The LHV for a hardwood with 10% moisture content is 16.5 MJ/kg. If .227 kg of wood was burned then 3.746 MJ were released due to the burning. The 2.5 kW heater was left on for 4 minutes and 25 seconds emitting .663 MJ. The reactors skin did increase in temperature but it was in such a short time and a low temperature that we will assume this value to be low. A total of 4.409MJ were released. Even if all that energy was transmitted to the air instead of the rest of the material inside the canister this would only raise the temperature by 217 K. This was clearly not observed so now we need to look at a smaller region.

Since none of these theories explain the pressure rise we need to look at a different scenario. One thing to consider is that the canister did shoot the grate off the bottom of the canister and visually appeared as if a blast or rocket like exhaust came out from the bottom of the canister. Since the pressure line was taken from the exhaust which had the blast directed directly at it could have skewed the pressure readings. If we assume combustion took place inside the canister almost instantly and this caused a dramatic increase in temperature and pressure due to a smaller volume of air this can easily explain the observed rise in pressure.

Appendix B:

STANJAN Simulation Results

COWBOY OAK WOOD COARSE (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.14300000E+00 -1.0513 H 5.81460000E+00 -8.7949 O 2.75260000E+00 -47.7431 N 1.00000000E-02 -13.9987

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.617 kg/kmol CH4 .22460E+00 .11278E+00 .10437E+00 6.49268E-01 CO .12667E-02 .63608E-03 .10277E-02 3.66176E-03 CO2 .21590E+00 .10841E+00 .27521E+00 6.24114E-01 H2 .37378E-01 .18770E-01 .21826E-02 1.08053E-01 H2O .51913E+00 .26069E+00 .27090E+00 1.50071E+00 NO .38509E-23 .19338E-23 .33471E-23 1.11323E-23 NO2 .90405E-38 .45398E-38 .12048E-37 2.61344E-38

N2 .17296E-02 .86854E-03 .14034E-02 5.00000E-03 O2 .44371E-31 .22281E-31 .41125E-31 1.28268E-31 phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49784E+00 .34491E+00 2.86596E+00 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.337 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6008E-01 m**3/kg U =-6.1748E+06 J/kg H =-6.0126E+06 J/kg S = 6.6486E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAKWOOD COARSE (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.08470000E+00 -1.0513 H 5.93370000E+00 -8.7939 O 2.80010000E+00 -47.7446 N 6.40000000E-03 -14.2310

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.591 kg/kmol CH4 .22550E+00 .11590E+00 .10656E+00 6.63798E-01 CO .12649E-02 .65012E-03 .10436E-02 3.72331E-03 CO2 .21527E+00 .11065E+00 .27907E+00 6.33686E-01 H2 .37453E-01 .19250E-01 .22241E-02 1.10249E-01 H2O .51942E+00 .26697E+00 .27565E+00 1.52900E+00 NO .30485E-23 .15669E-23 .26947E-23 8.97386E-24 NO2 .71465E-38 .36732E-38 .96851E-38 2.10367E-38 N2 .10871E-02 .55874E-03 .89703E-03 3.20000E-03 O2 .44243E-31 .22740E-31 .41702E-31 1.30236E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48602E+00 .33455E+00 2.78349E+00

40 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.449 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6279E-01 m**3/kg U =-6.2834E+06 J/kg H =-6.1184E+06 J/kg S = 6.7377E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAK WOOD FINE (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.29870000E+00 -1.0513 H 6.11230000E+00 -8.7668 O 2.59320000E+00 -47.8060 N 1.00000000E-02 -13.9983

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 21.866 kg/kmol CH4 .25137E+00 .12290E+00 .11716E+00 7.26075E-01 CO .11896E-02 .58163E-03 .96804E-03 3.43608E-03 CO2 .19041E+00 .93097E-01 .24345E+00 5.49992E-01 H2 .39543E-01 .19334E-01 .23160E-02 1.14220E-01 H2O .51576E+00 .25218E+00 .26996E+00 1.48978E+00 NO .36179E-23 .17689E-23 .31541E-23 1.04503E-23 NO2 .79764E-38 .39000E-38 .10662E-37 2.30398E-38 N2 .17310E-02 .84635E-03 .14088E-02 5.00000E-03 O2 .39133E-31 .19133E-31 .36380E-31 1.13035E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .51106E+00 .36474E+00 3.01920E+00

42 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 16.829 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6057E-01 m**3/kg U =-5.9277E+06 J/kg H =-5.7650E+06 J/kg S = 6.6716E+03 J/kg-K

Made 0 (T,P) iterations; 12 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAK WOOD FINE (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.09800000E+00 -1.0513 H 6.03290000E+00 -8.7868 O 2.77010000E+00 -47.7600 N 6.40000000E-03 -14.2328

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.400 kg/kmol CH4 .23206E+00 .11931E+00 .11031E+00 6.85610E-01 CO .12455E-02 .64037E-03 .10337E-02 3.67985E-03 CO2 .20874E+00 .10732E+00 .27220E+00 6.16721E-01 H2 .37994E-01 .19534E-01 .22695E-02 1.12251E-01 H2O .51887E+00 .26677E+00 .27698E+00 1.53298E+00 NO .29965E-23 .15406E-23 .26642E-23 8.85291E-24 NO2 .69171E-38 .35563E-38 .94293E-38 2.04361E-38 N2 .10831E-02 .55687E-03 .89901E-03 3.20000E-03 O2 .42901E-31 .22057E-31 .40675E-31 1.26749E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48587E+00 .33631E+00 2.79199E+00

44 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.352 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6375E-01 m**3/kg U =-6.2548E+06 J/kg H =-6.0888E+06 J/kg S = 6.7711E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD BLOCKS (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.13460000E+00 -1.0513 H 5.90390000E+00 -8.7704 O 2.53450000E+00 -47.8004 N 2.50000000E-02 -13.5269

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 21.960 kg/kmol CH4 .24772E+00 .12211E+00 .11581E+00 6.96728E-01 CO .11962E-02 .58967E-03 .97644E-03 3.36444E-03 CO2 .19253E+00 .94911E-01 .24693E+00 5.41525E-01 H2 .39255E-01 .19351E-01 .23062E-02 1.10408E-01 H2O .51485E+00 .25380E+00 .27031E+00 1.44809E+00 NO .58294E-23 .28736E-23 .50978E-23 1.63957E-23 NO2 .12924E-37 .63708E-38 .17328E-37 3.63489E-38 N2 .44443E-02 .21908E-02 .36282E-02 1.25000E-02 O2 .39570E-31 .19506E-31 .36900E-31 1.11295E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50704E+00 .36003E+00 2.89298E+00

46 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 16.916 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6107E-01 m**3/kg U =-5.9590E+06 J/kg H =-5.7957E+06 J/kg S = 6.6891E+03 J/kg-K

Made 0 (T,P) iterations; 12 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD BLOCKS (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.04310000E+00 -1.0513 H 5.68570000E+00 -8.8004 O 2.74820000E+00 -47.7315 N 8.60000000E-03 -14.0678

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.763 kg/kmol CH4 .21973E+00 .11129E+00 .10228E+00 6.27209E-01 CO .12816E-02 .64909E-03 .10415E-02 3.65814E-03 CO2 .22100E+00 .11193E+00 .28218E+00 6.30820E-01 H2 .36971E-01 .18725E-01 .21624E-02 1.05531E-01 H2O .51951E+00 .26312E+00 .27155E+00 1.48290E+00 NO .36361E-23 .18416E-23 .31657E-23 1.03790E-23 NO2 .86365E-38 .43742E-38 .11528E-37 2.46521E-38 N2 .15064E-02 .76298E-03 .12244E-02 4.30000E-03 O2 .45420E-31 .23004E-31 .42167E-31 1.29647E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49352E+00 .33956E+00 2.78141E+00

48 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.457 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6035E-01 m**3/kg U =-6.2381E+06 J/kg H =-6.0756E+06 J/kg S = 6.6558E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD COARSE (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.19960000E+00 -1.0513 H 5.90390000E+00 -8.7753 O 2.58820000E+00 -47.7873 N 1.50000000E-02 -13.7862

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.091 kg/kmol CH4 .24298E+00 .11912E+00 .11273E+00 6.88704E-01 CO .12120E-02 .59416E-03 .98172E-03 3.43521E-03 CO2 .19765E+00 .96894E-01 .25154E+00 5.60208E-01 H2 .38878E-01 .19059E-01 .22665E-02 1.10194E-01 H2O .51664E+00 .25328E+00 .26916E+00 1.46435E+00 NO .45574E-23 .22342E-23 .39548E-23 1.29173E-23 NO2 .10237E-37 .50185E-38 .13620E-37 2.90151E-38 N2 .26461E-02 .12972E-02 .21436E-02 7.50000E-03 O2 .40621E-31 .19914E-31 .37588E-31 1.15135E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50976E+00 .36117E+00 2.94725E+00

50 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 16.952 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.5983E-01 m**3/kg U =-5.9719E+06 J/kg H =-5.8099E+06 J/kg S = 6.6458E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD COARSE (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.04810000E+00 -1.0513 H 5.84440000E+00 -8.7922 O 2.73890000E+00 -47.7487 N 9.30000000E-03 -14.0351

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.545 kg/kmol CH4 .22703E+00 .11593E+00 .10695E+00 6.56428E-01 CO .12596E-02 .64323E-03 .10361E-02 3.64202E-03 CO2 .21349E+00 .10902E+00 .27590E+00 6.17286E-01 H2 .37580E-01 .19190E-01 .22247E-02 1.08657E-01 H2O .51903E+00 .26504E+00 .27458E+00 1.50069E+00 NO .36926E-23 .18856E-23 .32538E-23 1.06767E-23 NO2 .86206E-38 .44021E-38 .11646E-37 2.49250E-38 N2 .16082E-02 .82125E-03 .13229E-02 4.65000E-03 O2 .43878E-31 .22406E-31 .41228E-31 1.26865E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48935E+00 .33798E+00 2.77074E+00

52 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.390 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6228E-01 m**3/kg U =-6.2418E+06 J/kg H =-6.0774E+06 J/kg S = 6.7219E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD FINE (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.14880000E+00 -1.0513 H 5.82460000E+00 -8.7928 O 2.73320000E+00 -47.7485 N 1.50000000E-02 -13.7952

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.559 kg/kmol CH4 .22649E+00 .11346E+00 .10525E+00 6.53690E-01 CO .12599E-02 .63119E-03 .10222E-02 3.63644E-03 CO2 .21360E+00 .10701E+00 .27229E+00 6.16489E-01 H2 .37535E-01 .18804E-01 .21918E-02 1.08334E-01 H2O .51853E+00 .25977E+00 .27059E+00 1.49659E+00 NO .46949E-23 .23520E-23 .40808E-23 1.35506E-23 NO2 .10963E-37 .54922E-38 .14610E-37 3.16419E-38 N2 .25985E-02 .13018E-02 .21085E-02 7.50000E-03 O2 .43899E-31 .21992E-31 .40688E-31 1.26701E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49902E+00 .34655E+00 2.87498E+00

54 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.295 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6009E-01 m**3/kg U =-6.1480E+06 J/kg H =-5.9857E+06 J/kg S = 6.6500E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

DOW CORNING OAK WOOD FINE (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.08300000E+00 -1.0513 H 5.83450000E+00 -8.7947 O 2.76070000E+00 -47.7432 N 7.90000000E-03 -14.1180

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.612 kg/kmol CH4 .22480E+00 .11431E+00 .10539E+00 6.51678E-01 CO .12666E-02 .64408E-03 .10367E-02 3.67179E-03 CO2 .21586E+00 .10977E+00 .27761E+00 6.25770E-01 H2 .37395E-01 .19016E-01 .22030E-02 1.08405E-01 H2O .51932E+00 .26408E+00 .27341E+00 1.50549E+00 NO .34177E-23 .17379E-23 .29970E-23 9.90770E-24 NO2 .80227E-38 .40797E-38 .10786E-37 2.32576E-38 N2 .13626E-02 .69288E-03 .11154E-02 3.95000E-03 O2 .44364E-31 .22560E-31 .41484E-31 1.28609E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49149E+00 .33924E+00 2.80188E+00

56 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.402 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6150E-01 m**3/kg U =-6.2348E+06 J/kg H =-6.0712E+06 J/kg S = 6.6952E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

REDOAK (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.08390000E+00 -1.0513 H 5.87420000E+00 -8.7952 O 2.78640000E+00 -47.7415 N 4.30000000E-03 -14.4258

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.626 kg/kmol CH4 .22435E+00 .11469E+00 .10552E+00 6.55178E-01 CO .12687E-02 .64856E-03 .10418E-02 3.70511E-03 CO2 .21660E+00 .11072E+00 .27945E+00 6.32523E-01 H2 .37358E-01 .19097E-01 .22079E-02 1.09095E-01 H2O .51969E+00 .26566E+00 .27448E+00 1.51765E+00 NO .25165E-23 .12864E-23 .22138E-23 7.34893E-24 NO2 .59174E-38 .30249E-38 .79811E-38 1.72805E-38 N2 .73623E-03 .37635E-03 .60462E-03 2.15000E-03 O2 .44515E-31 .22755E-31 .41758E-31 1.29997E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48881E+00 .33670E+00 2.79249E+00

58 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.437 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6202E-01 m**3/kg U =-6.2664E+06 J/kg H =-6.1023E+06 J/kg S = 6.7114E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

REDOAK (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.24790000E+00 -1.0513 H 5.98330000E+00 -8.7779 O 2.65570000E+00 -47.7792 N 4.30000000E-03 -14.4194

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.164 kg/kmol CH4 .24041E+00 .11838E+00 .11165E+00 6.93180E-01 CO .12218E-02 .60167E-03 .99073E-03 3.52297E-03 CO2 .20088E+00 .98917E-01 .25592E+00 5.79195E-01 H2 .38671E-01 .19043E-01 .22568E-02 1.11502E-01 H2O .51808E+00 .25512E+00 .27019E+00 1.49379E+00 NO .24390E-23 .12010E-23 .21187E-23 7.03232E-24 NO2 .55230E-38 .27197E-38 .73558E-38 1.59246E-38 N2 .74566E-03 .36719E-03 .60469E-03 2.15000E-03 O2 .41284E-31 .20330E-31 .38242E-31 1.19037E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50757E+00 .35839E+00 2.97200E+00

60 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.011 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.5999E-01 m**3/kg U =-6.0206E+06 J/kg H =-5.8584E+06 J/kg S = 6.6489E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAK WOOD 2000(HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.17380000E+00 -1.0513 H 5.93370000E+00 -8.7937 O 2.79760000E+00 -47.7450 N 5.70000000E-03 -14.2886

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49408E+00 .34183E+00 2.87315E+00

62 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.360 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6106E-01 m**3/kg U =-6.2104E+06 J/kg H =-6.0472E+06 J/kg S = 6.6806E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAK WOOD 2003 (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.23040000E+00 -1.0513 H 5.95360000E+00 -8.7856 O 2.72070000E+00 -47.7628 N 7.90000000E-03 -14.1199

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.368 kg/kmol CH4 .23315E+00 .11589E+00 .10835E+00 6.78435E-01 CO .12420E-02 .61735E-03 .10078E-02 3.61412E-03 CO2 .20756E+00 .10317E+00 .26461E+00 6.03987E-01 H2 .38083E-01 .18929E-01 .22240E-02 1.10817E-01 H2O .51861E+00 .25778E+00 .27065E+00 1.50911E+00 NO .33450E-23 .16627E-23 .29077E-23 9.73373E-24 NO2 .76998E-38 .38272E-38 .10262E-37 2.24057E-38 N2 .13574E-02 .67472E-03 .11015E-02 3.95000E-03 O2 .42658E-31 .21204E-31 .39541E-31 1.24132E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50294E+00 .35205E+00 2.94436E+00

64 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.159 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6010E-01 m**3/kg U =-6.0920E+06 J/kg H =-5.9297E+06 J/kg S = 6.6511E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

COWBOY OAK WOOD SAWDUST 2003 (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.23710000E+00 -1.0513 H 5.78490000E+00 -8.7859 O 2.64450000E+00 -47.7630 N 1.21000000E-02 -13.8928

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.375 kg/kmol CH4 .23288E+00 .11329E+00 .10658E+00 6.59069E-01 CO .12418E-02 .60410E-03 .99229E-03 3.51434E-03 CO2 .20748E+00 .10094E+00 .26050E+00 5.87195E-01 H2 .38061E-01 .18516E-01 .21890E-02 1.07717E-01 H2O .51821E+00 .25210E+00 .26634E+00 1.46659E+00 NO .41969E-23 .20417E-23 .35929E-23 1.18778E-23 NO2 .96588E-38 .46989E-38 .12678E-37 2.73357E-38 N2 .21377E-02 .10400E-02 .17084E-02 6.05000E-03 O2 .42641E-31 .20745E-31 .38926E-31 1.20681E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .51351E+00 .36169E+00 2.98732E+00

66 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.053 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.5768E-01 m**3/kg U =-5.9888E+06 J/kg H =-5.8291E+06 J/kg S = 6.5718E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

LAUREL WOOD (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.19210000E+00 -1.0513 H 5.77500000E+00 -8.7812 O 2.59320000E+00 -47.7732 N 1.14000000E-02 -13.9176

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.251 kg/kmol CH4 .23724E+00 .11547E+00 .10900E+00 6.64657E-01 CO .12292E-02 .59829E-03 .98609E-03 3.44377E-03 CO2 .20331E+00 .98957E-01 .25626E+00 5.69598E-01 H2 .38416E-01 .18698E-01 .22180E-02 1.07625E-01 H2O .51776E+00 .25201E+00 .26715E+00 1.45056E+00 NO .40531E-23 .19727E-23 .34833E-23 1.13550E-23 NO2 .92336E-38 .44942E-38 .12167E-37 2.58688E-38 N2 .20346E-02 .99027E-03 .16323E-02 5.70000E-03 O2 .41785E-31 .20338E-31 .38293E-31 1.17064E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .51327E+00 .36275E+00 2.95440E+00

68 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 16.995 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.5829E-01 m**3/kg U =-5.9715E+06 J/kg H =-5.8111E+06 J/kg S = 6.5930E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

LAUREL WOOD (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.07470000E+00 -1.0513 H 5.85430000E+00 -8.7874 O 2.69070000E+00 -47.7601 N 1.43000000E-02 -13.8167

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.414 kg/kmol CH4 .23149E+00 .11708E+00 .10875E+00 6.64917E-01 CO .12453E-02 .62986E-03 .10214E-02 3.57707E-03 CO2 .20868E+00 .10554E+00 .26892E+00 5.99402E-01 H2 .37947E-01 .19193E-01 .22401E-02 1.08997E-01 H2O .51815E+00 .26207E+00 .27335E+00 1.48832E+00 NO .45419E-23 .22972E-23 .39910E-23 1.30460E-23 NO2 .10483E-37 .53020E-38 .14123E-37 3.01110E-38 N2 .24892E-02 .12590E-02 .20419E-02 7.15000E-03 O2 .42888E-31 .21692E-31 .40185E-31 1.23190E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .49423E+00 .34368E+00 2.80680E+00

70 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.272 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6183E-01 m**3/kg U =-6.1695E+06 J/kg H =-6.0055E+06 J/kg S = 6.7089E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

SWEETGUM (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.15710000E+00 -1.0513 H 5.96350000E+00 -8.7774 O 2.64010000E+00 -47.7809 N 6.40000000E-03 -14.2185

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.149 kg/kmol CH4 .24095E+00 .12015E+00 .11295E+00 6.91879E-01 CO .12198E-02 .60827E-03 .99834E-03 3.50260E-03 CO2 .20021E+00 .99836E-01 .25745E+00 5.74887E-01 H2 .38715E-01 .19306E-01 .22805E-02 1.11168E-01 H2O .51779E+00 .25821E+00 .27257E+00 1.48682E+00 NO .29767E-23 .14844E-23 .26100E-23 8.54738E-24 NO2 .67294E-38 .33557E-38 .90465E-38 1.93232E-38 N2 .11144E-02 .55572E-03 .91218E-03 3.20000E-03 O2 .41147E-31 .20518E-31 .38471E-31 1.18151E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50133E+00 .35283E+00 2.88683E+00

72 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.066 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6149E-01 m**3/kg U =-6.0723E+06 J/kg H =-5.9087E+06 J/kg S = 6.6988E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

SWEETGUM (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 3.98730000E+00 -1.0513 H 5.86430000E+00 -8.7942 O 2.76950000E+00 -47.7443 N 8.60000000E-03 -14.0777

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.599 kg/kmol CH4 .22522E+00 .11684E+00 .10709E+00 6.55732E-01 CO .12652E-02 .65632E-03 .10503E-02 3.68346E-03 CO2 .21537E+00 .11173E+00 .28093E+00 6.27053E-01 H2 .37430E-01 .19417E-01 .22364E-02 1.08976E-01 H2O .51923E+00 .26936E+00 .27724E+00 1.51171E+00 NO .35542E-23 .18438E-23 .31610E-23 1.03479E-23 NO2 .83339E-38 .43233E-38 .11364E-37 2.42637E-38 N2 .14769E-02 .76618E-03 .12262E-02 4.30000E-03 O2 .44264E-31 .22963E-31 .41979E-31 1.28873E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48124E+00 .33023E+00 2.70083E+00

74 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.503 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6379E-01 m**3/kg U =-6.3241E+06 J/kg H =-6.1582E+06 J/kg S = 6.7710E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

WHITEOAK (HUFFMAN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.06140000E+00 -1.0513 H 5.92380000E+00 -8.7921 O 2.77640000E+00 -47.7483 N 5.00000000E-03 -14.3518

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.542 kg/kmol CH4 .22719E+00 .11682E+00 .10755E+00 6.65321E-01 CO .12602E-02 .64800E-03 .10416E-02 3.69047E-03 CO2 .21368E+00 .10988E+00 .27750E+00 6.25772E-01 H2 .37593E-01 .19331E-01 .22363E-02 1.10092E-01 H2O .51943E+00 .26710E+00 .27614E+00 1.52117E+00 NO .26915E-23 .13840E-23 .23833E-23 7.88215E-24 NO2 .62861E-38 .32324E-38 .85342E-38 1.84091E-38 N2 .85367E-03 .43897E-03 .70567E-03 2.50000E-03 O2 .43916E-31 .22582E-31 .41467E-31 1.28609E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .48578E+00 .33483E+00 2.76662E+00

76 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.426 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6308E-01 m**3/kg U =-6.2799E+06 J/kg H =-6.1146E+06 J/kg S = 6.7474E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

WHITEOAK (HAZEN) 3:35 PM 8/27/2012 By Greg Specht JANNAF table data for the products at T = 673.00 K

species molal mass enth. form S0 H-H0 g/mol kcal/mol cal/mol-K kcal/mol

phase 2; Condensed species: Density, g/cc C(S) 12.01100 .000 3.953 1.253 2.700

phase 3; Condensed species: Density, g/cc H2O(L) 18.01601 -68.315 36.070 10.189 1.000

Computed properties

Independent population element atom potential C 4.22040000E+00 -1.0513 H 5.97340000E+00 -8.7799 O 2.67140000E+00 -47.7748 N 4.30000000E-03 -14.4204

Products at T = 673.00 K P = 1.000E+01 atmospheres

species mol fraction mol fraction mass fraction mols* in the phase in mixture in mixture

phase 1: molal mass = 22.216 kg/kmol CH4 .23856E+00 .11818E+00 .11109E+00 6.89098E-01 CO .12272E-02 .60791E-03 .99775E-03 3.54476E-03 CO2 .20263E+00 .10038E+00 .25885E+00 5.85313E-01 H2 .38522E-01 .19083E-01 .22543E-02 1.11275E-01 H2O .51832E+00 .25677E+00 .27106E+00 1.49723E+00 NO .24473E-23 .12124E-23 .21317E-23 7.06936E-24 NO2 .55661E-38 .27573E-38 .74333E-38 1.60782E-38 N2 .74430E-03 .36872E-03 .60523E-03 2.15000E-03 O2 .41644E-31 .20630E-31 .38681E-31 1.20294E-31

phase 2: molal mass = 12.011 kg/kmol C(S) .10000E+01 .50462E+00 .35514E+00 2.94244E+00

78 phase 3: molal mass = .000 kg/kmol H2O(L) .00000E+00 .00000E+00 .00000E+00 0.00000E+00

* Species mols for the atom populations in mols.

Mixture properties: molal mass = 17.066 kg/kmol T = 673.00 K P = 1.0133E+06 Pa V = 1.6043E-01 m**3/kg U =-6.0566E+06 J/kg H =-5.8940E+06 J/kg S = 6.6628E+03 J/kg-K

Made 0 (T,P) iterations; 11 equilibrium iterations; v 3.90 IBM-PC

Works Cited

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[2] M. J. Antal, E. Croiset, X. Dai, C. DeAlmeida, W. S.-L. Mok and N. Norberg, "High-Yield Biomass Charcoal," energy & fuels, vol. 10, no. 3, 1996.

[3] M. J. Antal, S. G. Allen, X. Dai, B. Shimizu, M. S. Tam and M. Gronoli, "Attainment of the Thoeretical Yield of Carbon from Biomass," Industry & Engineering Chemistry Research, vol. 39, no. 11, pp. 4024-4031, 2000.

[4] M. J. Antal, K. Mochidzuki and L. S. Paredes, "Flash Carbonization of Biomass," Industry & Engineering Chemistry Research, vol. 42, no. 16, pp. 3690-3699, 2003.

[5] G. Agricola, De Re Metallica, New York: Dover Publications, Inc., 1950.

[6] A. Braga and S. P. Moreira, "New processes for the production of solar-grade polycrystalline silicon: A review," Science Direct, pp. 418-424, 2007.

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[9] M. A. Quintana and D. L. King, "COMMONLY OBSERVED DEGRADATION IN FIELD-AGED PHOTOVOLTAIC MODULES," in Photovoltaic Specialists Conference, New Orleans, 2002.

[10] American Society of Testing and Materials. Standard Test Method For Determination of Total Solids in Biomass. ASTM E 1756-95.

[11] American Society of Testing and Materials. Standard Method for Chemical Analysis of Wood Charcoal. ASTM D 1762-84.

[12] Aristophanes, Artist, The Acharnians. [Art]. 425 B.C..

[13] M. J. Antal and M. Gronli, "The Art, Science, and Technology of Charcoal Production," Ind. Eng. Chem. Res., vol. 42, pp. 1619-1640, 2003.

[14] How it's Made Charcoal. [Film]. United States of America: Science Channel, 2010.

[15] W. C. Reynolds, STANJAN Notes.

[16] J. P. Lacaux, D. Brocard, C. Lacaux and R. Delmas, "Traditional charcoal making: An important source of atmospheric pollution in the," Atmospheric Research, vol. 35, pp. 71-76, 1994.

[17] M. J. Antal, K. W. Boer and J. A. Duffie, "Biomass Pyrolysis: A Review of the Literature. Part 2- Lignocellulose Pyrolysis.," Advances in Solar Energy, vol. 2, pp. 175-255, 1985.

[18] M. J. Antal and G. Varhegyi, "Cellulose Pyrolysis Kinetics: The Current State of Knowledge," Ind. Eng. Chem. Res., vol. 34, pp. 703-717, 1995.

[19] M. J. Antal and G. Varhegyi, "Impact of Systematic Errors on the Determination of Cellulose," Energy Fuels, vol. 11, no. 6, pp. 1309-1310, 1997.

[20] M. J. Antal, G. Varhegyi, T. Szekely, F. Till and E. Jakab, "Simultaneous Thermogravimetric-Mass Spectrometric Studies of the Thermal Decomposition of Biopolymers," Energy Fuels, vol. 2, pp. 267- 272, 1988.

[21] E. Cetin, B. Moghtaderi, R. Gupta and T. Wall, "Influence of pyrolysis conditions on the structure and gasification reactivity of biomass chars," Fuel, vol. 83, no. 16, pp. 2139-2150, 2004.

[22] J. Joyce, T. Dixon and J. C. Diniz De Costa, "Characterization of Sugar Cane Waste Biomass Characterization of Sugar Cane Waste Biomass," Process Safety and Environmental Protection, vol. 84, no. B6, pp. 429-439, 2006.

[23] Encyclopedia Britanica Inc., "Chemical Equilibrium," Encyclopedia Britanica Online, [Online]. Available: http://global.britannica.com/EBchecked/topic/687367/chemical-equilibrium. [Accessed 2013].

[24] Y. A. Cengel and M. A. Boles, Thermodynamics An Engineering Approach, Boston: WCB McGraw- Hill, 1998.