<<

Large Scale Production of Via of Waste Plastic Gas

By

Babatunde I. Ojoawo

Submitted in Partial Fulfilment of the Requirements

for the Degree of

Master of Science in Engineering

in the

Chemical Engineering

Program

YOUNGSTOWN STATE UNIVERSITY

August, 2020

i Large Scale Production of Hydrogen Via Steam Reforming of Waste Plastic Pyrolysis Gas

Babatunde I. Ojoawo

I hereby release this thesis to the public. I understand that this thesis will be made available from the OhioLINK ETD Center and the Maag Library Circulation Desk for public access. I also authotize the University or other individuals to make copies of this thesis as needed for scholarly research.

Signature:

………………………………………... ……………….. Babatunde I. Ojoawo Date

Approvals:

………………………………………… 07/27/2020 Dr. Douglas Price, Thesis Advisor Date

………………………………………… …………………. Dr. Pedro Cortes, Committee Member Date

…………………………………………….. ………………….. Dr. Byung-Wook Park, Committee Member Date

…………………………………………… …………………. Dr. Salvatore A. Sanders, Dean of Graduate Date Studies

ii Abstract

Plastic is one of the environmental problems facing the United States and the world at large. This project suggests solutions to the problem by using the plastic waste to produce a green and clean energy which will reduce the amount of plastic waste as well as making the environment a haven. With the increase in level, the world is adopting the use of clean and green fuel. This work considers using steam reforming of volatile products from pyrolysis of high-density polyethylene (HDPE) at 500oC to mass- produce hydrogen gas. 50 metric tonnes/day of waste HDPE plastic and 7841litre/ day of generated steam feed will be converted into 5,128.2 metric tonnes of pure hydrogen gas per year using a adiabatic, fixed-bed catalytic reactors operating at 649.3°C and 1 bar. The catalyst is a commercial Ni in the form of 0.4-0.8m particle size.

iii Acknowledgement

I am using this medium to express my sincere gratitude to my Advisor Dr. Price who gives me the opportunity to work on this project which is one the solutions to the problems facing the world. I also thank him for the opportunity to learn from his wealth of knowledge. I am thankful to Dr. Cortes who unconditionally allowed me to learn from his research experience and accepted, to be one of my thesis committee. I thank Dr. Park who constantly encouraging me to pursue my goals and accepted to be thesis committee.

Special appreciation to Dr. Sherri Lovelace-Cameron (Chemistry Dept.) and Dr. Sal

Sanders (Dean of Graduate Studies) who made it possible for me to accept the graduate admission by avail me the opportunity of Graduate Assistantship in my first year in graduate school. I also thank Dr. Holly Martin who allowed me to learn the skills used in the execution of this project.

Most importantly, I would not have achieved this success without the love and support of my lovely wife; Atinuke Ibrahim-Ojoawo and my two wonderful children; Daniella and

Asher Ibrahim-Ojoawo. I love you all.

iv Table of Contents

Title Page………………………………………………………………………...... i

Signature Page…………………………………………………………………...... ii

Abstract…………………………………………………………………………………...iii

Acknowledgement……………………………………………………………...... iv

Table of Content…………………………………………………………………………...v

List of Figures…………………………………………………………………...... vi

List of Tables……………………………………………………………………………..vii

Chapter 1: Introduction………………………………………………………………….1

Global Market of Hydrogen……………………………………………………………….2

Chapter 2 : Methodology of the kinetic study…………………………………………...7

Experimental Procedure………………………………………………………7

Kinetic Model………………………………………………………………....8

Exponential Factor…………………………………………………………..11

Chapter 3: Process Description………………………………………………...... 12

Feed Storage…………………………………………………………………12

Reactor Unit……………………………………………………………...….12

Separation Unit………………………………………………………………14

Energy Balance and Utility Requirement…………………………………….15

Economic Analysis and Market Analysis…………………………………….17

v

Safety Consideration………………………………………………….……..18

Chapter 4: Conclusion………………………………………………………………….20

Chapter 5: References…………………………………………………………………..22

Appendix…………………………………………………………………..…25

vi

List of Figures

1.1 Cost of Hydrogen………………………………………………………………..…….5

2.1 Kinetic Scheme for the reforming step of the volatile pyrolyzed HDPE products……………………………………………………………………………………9

3.1 Process Flow Diagram of the production of hydrogen…………………………….….15

vii

List of Tables

2.1 Volatile products of pyrolyzed HDPE………………………………………………....7

2.2 Scaled up volatile products of the pyrolyzed HDPE…………………………………...8

2.3 Parameters of the Equilibrium Constant in the WGS Reaction………………………10

2.4 Exponential factors for the kinetic model…………………………………………….11

3.1 Details of the reforming reactor……………………………………………...……….13

3.2 Utility cost for ……...……………………………...…………...16

3.3 Summary of Equipment Cost for Hydrogen Production………………...………...….17

viii

CHAPTER ONE

Introduction

Plastics products are highly convenient due to their resistance to degradation,

versatility, light weight, and low price. As a result, their use has increased by

twentyfold in the past 60 years and so has the amount of plastic waste generated. EPA

(U.S Environmental Protection Agency) estimates that global carbon footprint of plastic

waste is somewhere between 100 - 300 million tonnes of CO2 equivalent. To put those figures into context, plastics waste carbon footprint is equivalent to the carbon emissions of 21- 63 million cars driven for one year [1] Every year the amount of plastic waste from packaging increases at a higher rate than the recycled fraction, meaning more plastic waste are diverted to landfill and incineration. of plastics is constrained by the addition of substances during their manufacture to improve the product quality and properties. At the end of the product life, those substances cannot be separated or removed and they decrease the quality of recycled products or even eliminates the possibility of recycling completely [2]. Disposing plastic waste in landfills presents two problems: firstly, as they are not biodegradable, they break into small particles harmful for human and wild life; and secondly, 4% of the global oil production is used to manufacture plastics products [3], 50% of which have a short life so useful raw materials are disposed as waste in less than a year. Thermal treatments such as pyrolysis or are excellent alternatives for sustainable from MPW into fuels and chemicals [4]. Nowadays, the interest in polymeric material pyrolysis is increasing.

Two principal application fields are found: innovative polymer recycling techniques

[5],[6],[7] and solid fuel for aerospace applications. During polymer’s recycling, the

1 applied temperature, and the way to heat-up polymeric material both determine which final products are obtained. The degradation of plastics in a variety of different reactor types has been investigated at various processing scales [8]. Polyethylene and polypropylene are the major components of plastic wastes from domestic refuse. Until now, plastic wastes have been mainly disposed of by landfill or incineration, which are inefficient and highly contaminating techniques [9]. These processes are not acceptable under policies which focus on efficient recovery of raw material and energy. Pyrolysis and gasification processes are promising routes for optimal material recycling. Moreover, pyrolysis of plastics at different temperatures allows the treatment of polymers with simultaneous decomposition and separation. Combustible, gases, and energy can be obtained at the same time with only one recycling process. Logically, the first step for a suitable design of any pyrolysis reactor intended to plastic recycling is a high knowledge and a control of the involved kinetics.

1.1 The Global Market of Hydrogen

Hydrogen production is a large and growing industry: with as of 2019 about 70 million tonnes of dedicated production per year, larger than the primary energy supply of Germany

[10]. The global hydrogen energy storage market is projected to reach USD 18.2 billion by

2024 from an estimated USD 13.7 billion in 2019, at a CAGR of 5.8% during the forecast period, The hydrogen energy storage market in North America is projected to grow at the fastest rate during the forecast period. The major reason for the growth in this region is attributed to the rise in applications, tight regulations regarding emission control, and the use of cleaner fuels. Furthermore, the growing demand for hydrogen-powered fuel cells is also likely to drive the market in this region [11]. prices range from

2

$12.85 to more than $16 per kilogram (kg), but the most common price is $13.99 per kg

(equivalent on a price per energy basis to $5.60 per gallon of ), which translates to an operating cost of $0.21 per mile. Automakers are including three years of hydrogen fuel with their initial sales and lease offerings, which will shield early market adopters from this initially high fuel price. While future price is uncertain, NREL (National Renewable

Energy Laboratory) estimates that hydrogen fuel prices may fall to the $10 to $8 per kg range in the 2020 to 2025 period. A kilogram of hydrogen has about the same energy content as a gallon of gasoline. FCEVs (Fuel Cell ) are about twice as efficient as gasoline-powered vehicles: an FCEV travels about twice as far as a conventional vehicle given the same amount of fuel energy. At $3.50 per gallon gasoline, a conventional vehicle costs about $0.13 per mile to operate, while an FCEV using $8 per kg hydrogen fuel would cost about $0.12 per mile [12].

Deployment of hydrogen can provide a cost-effective option to displace fossil fuels in applications where emissions reductions would otherwise be impractical and/or expensive.[13] These may include heat for buildings and industry, conversion of -fired power stations,[14] and fuel for aviation and possibly heavy trucks.[15] However switching from natural gas to low-carbon heating is more costly if the carbon costs of natural gas are not reflected in its price[16].

Although the cost of has fallen systems which use renewably generated electricity more directly, for example in trolleybuses, or in battery electric vehicles may have a significant economic advantage because there are fewer conversion processes required between primary energy source and point of use.

3

Different production methods each have differing associated investment and marginal costs. The energy and feedstock could originate from a multitude of sources, i.e. natural gas, , nuclear, solar, wind, , other fossil fuels, and geothermal.

The barrier to lowering the price of high purity hydrogen is a cost of more than 35 kWh of electricity used to generate each kilogram of hydrogen gas. Hydrogen produced by steam reformation costs approximately three times the cost of natural gas per unit of energy produced. This means that if natural gas costs $6 per million BTU, then hydrogen will be

$18/million BTU. Also, producing hydrogen from electrolysis with electricity at 5 cents/kWh would cost $28/million BTU — about 1.5 times the cost of hydrogen from natural gas. Note that the cost of hydrogen production from electricity is a linear function of electricity costs, so electricity at 10 cents/kWh would mean that hydrogen would cost

$56 per million BTU.[17] However costs are rapidly decreasing.[18] Hydrogen pipelines are more expensive [19] than even long-distance electric lines. Hydrogen is about three times bulkier in volume than natural gas for the same enthalpy. Hydrogen accelerates the of steel (hydrogen embrittlement), which increases maintenance costs, leakage rates, and material costs. The difference in cost is likely to expand with newer technology: wires suspended in air can use higher voltage with only marginally increased material costs, but higher-pressure pipes require proportionally more material. Setting up a would require huge investments in infrastructure. Power plant capacity that now goes unused at night could be used to produce hydrogen.

4

Fig 1: Cost of Hydrogen (Source: Bloomberg New Energy Finance, 2019)

As of 2019, production and oil refining are the main uses.[20] About half is used in the to produce (NH3), which is then used directly or indirectly as fertilizer. Because both the world population and the intensive agriculture used to support it are growing, ammonia demand is growing. Ammonia can be used as a safer and easier indirect method of transporting hydrogen. Transported ammonia can be then converted back to hydrogen at the bowser by a membrane technology[21].

The other half of current hydrogen production is used to convert heavy petroleum sources into lighter fractions suitable for use as fuels. This latter process is known as hydrocracking. Hydrocracking represents an even larger growth area, since rising oil prices encourage oil companies to extract poorer source material, such as oil sands and oil shale.

The scale economies inherent in large-scale oil refining and fertilizer manufacture make possible on-site production and "captive" use. Smaller quantities of "merchant" hydrogen

5 are manufactured and delivered to end users as well.

Hydrogen is industrially produced from steam reforming, which uses fossil fuels such as natural gas. [22] The energy content of the produced hydrogen is less than the energy content of the original fuel, some of it being lost as excess heat during production. Steam reforming emits . A small part (2% in 2019[23]) is produced by electrolysis using electricity and water, consuming approximately 50 kilowatt-hours of electricity per kilogram of hydrogen produced.

6

CHAPTER TWO

Methodology for the kinetic study

This project is designed using a kinetic model, the effect of the reaction conditions

(temperature, space time and catalyst masses) on the production of hydrogen via catalytic steam reforming of volatiles products from pyrolysis of waste plastic (HDPE) on Ni-based catalyst. The kinetic models for each step in the pyrolysis- catalytic steam reforming is needed for the simulation and optimization of the conditions and scaling up of the process for the commercial purpose.

Background on this kinetic modeling of steam reforming of HDPE refer exclusively to kinetic modeling of HDPE [24].

Experimental Procedure

This involves steam reforming of HDPE. The data in the table below are from the pyrolysis stage carried out by Itsaso Barbarias [24].

Table 2.1. Volatile products of pyrolyzed HDPE (Itsaso Barbarias et, al. 2017)

Feed Products (Volatiles) : Pyrolysis @ 500oC.

HDPE: 0.75g/min Waxes (C21+, 67 wt %, 0.50 g/min)

Diesel fraction (C12-C20, 25.6 wt %, 0.19g/min)

Gasoline (C5-C11, 5.9 wt %, 0.044g/min)

Light (C2-C4,1.47 wt %, 0.011g/min)

Methane (CH4, 0.03 wt %, 0.000225g/min)

7

This was scaled up to fit the desirable and feasible work in this project. The above data was re-modelled with the details in the table below:

Table 2.2: Scaled up volatile products of the pyrolyzed HDPE Feed Products (Volatiles)

HDPE (50 Wax: Uneicosane; C21H44, 33.49 metric tonnes/day metric tonnes/day of Diesel fraction: Hexanedecane; C16H34, 12.79 metric tonnes/day waste plastic) Gasoline: N-Decane; C10H22, 2.95 metric tonnes/ day

Light Hydrocarbon: n-, C3H8, 0.73 metric tonnes/day

Methane;CH4, 0.0149 metric tonnes/day

Kinetic Model

The development of kinetic model requires a good formulation of the elementary steps that lead from the feed materials to products. The general guidelines of this study have been developed for the kinetic modeling of the catalytic process at zero time on stream by

Barbarias and Toch et al[24] [25].

The figure below shows proposed kinetic scheme considering seven reactions.

8

Fig 2.1 Kinetic scheme for the reforming step of the volatile pyrolyzed HDPE products.

The reactions in the steam reforming reactor and water gas shift are stated below:

C5+ is modelled as (C5-C11, C12-C20 and C21+)

C5+ fraction reforming:

1. C21H44 + 21H2O 43H2 + 21CO

2. C16H34 + 16H2O 33H2 + 16CO

3. C10H22 + 10H2O 21H2 + 10CO

C2-C4 fraction reforming:

C3H8 + 3H2O 7H2 + 3CO

CH4 fraction reforming:

CH4 + H2O 3H2 + CO2

WGS (Water Gas Shift) reaction:

CO + H2O H2 + CO2

9

The rate of reaction expression are formulated assuming that they are first-order for each

reactant, the reaction kinetics has a clear physical meaning depending upon reactant partial

pressure and previous methane steam reforming kinetic studies showed that the reaction

orders with respect to methane are around 1, those of steam are diverse.[25]

The expressions are:

(r1)0 = k1X C21H44XH2O

(r1)0 = k1X C16H34XH2O

(r1)0 = k1X C10H22XH2O

(r2)0 = k2XC3H8XH2O

(r3)0 = k3XCH4XH2O

(r4)0 = kwgs(XCOXH2O – XH2XCO2/ Kwgs)

where Xi is the molar fraction of each component in the reaction medium and kj is the

kinetic constant of the reaction j in the kinetic scheme (eqs 1-6).

The equilibrium constant of the WGS reaction has been calculated by the following

expression

2 2 Kwgs = exp[ a + b(1/T) + c log(T) + dT + eT + f(1/T ) ]

Where parameters a-f (Table ) have been calculated by means of the methodology explained by Smith et al,[26]

Table 2.3: Parameters of the Equilibrium Constant in the WGS Reaction a b c d e f

Kwgs -1.8E1 5.8E3 1.8 -2.7E-4 0.0 -5.8E4

Source: Barbarias et al, 2017

10

Exponential factor

The methodology adopted in this study was developed by Oar-Artetal et al [27] and analyzed by Barbarias et al[24].

Each kinetic constant of the seven reactions were optimized. To get the frequency factors of reaction at different temperatures was calculated using the equation stated below where kj* is the kinetic constant at a reference temperature, T* (650oC).

kj = kj* exp[-Ej/R( 1/T – 1/T*) ]

Table 2.4: Exponential factors for the kinetic model. -1 Ej, (kJ mol ) A k (mol gcat/min)

C21H44, k1 17.0 1,145.14 0.200

C16H34, k1 17.0 1,145.14 0.200

C10H22, k1 17.0 1,145.14 0.200

C3H8, k2 17.10 696.10 0.120

CH4, k3 30.4 2,198 0.067

CO + H2O, kWGS 32.5 12,942 0.300

H2 + CO2, kr 70.03 2,153.74 242.7

The kinetic parameters i.e., the kinetic constants at the reference temperature of 650oC,

activation energies are summarized in table 2.4, alongside with frequency factor of each of

the reactions.

11

CHAPTER THREE

Process Description

Feed Storage

Having gather a huge amount of plastic waste. It is then cleaned and stored at atmospheric pressure and temperature in a very clean space. 50 metric tonnes/day of waste plastic undergoes pyrolysis at 500oC with the aim of using the volatile products to produce hydrogen via steam reforming. In addition, more waste plastic can be gotten by setting up an initiative of putting up a financial incentive to certain amount of waste plastic dropped by the individual instead of dumping it on our landfill.

Reactor Unit:

The details as regards the conditions and the stream’s contents are being specified in Tables in the appendices. The feed (volatiles products of pyrolyzed waste plastic at 500oC) mixed with steam in the mixer (M-101) where the pressure and temperature feed stream increase to 1 bar and 512.99oC. A combustor (C-101) is staged to provide energy (heat) to the reactor due to endothermic reaction to keep the temperature at the level where the reactor can perform in the gas phase. A fixed-bed reactor (H-101) in which the overall reactions of pyrolyzed volatiles products of waste plastics (Uneiscosane, Hexadecane, N-Decane, n-

Propane, Methane, water gas) and steam; accordingly, the steam to plastic ratio was 3.7 and steam to carbon (S/C) ratio in the reforming step was 2.7 to generate hydrogen and and other by products. It is sized and ensure a good conversion of higher hydrocarbon. The reactor is 0.76m3 . The reactor consists of 300 tubes of length 5m and

diameter 0.0254m and it is filled with 426kg Ni catalyst of size 0.4-0.8m.

12

At the exit, the products enter controller (CT-01) to maintain the stream temperature at

649.2oC from where it later enters heat exchanger (E-101) which lowers the temperature to 53.6oC. It is necessary to remove much heat since the separation unit requires low temperatures.

Table: 3.1 Details of the Reforming Reactor

REACTOR

Reactor Type Plug Flow

Thermal Mode Specified PFR utility U

Reaction Phase Vapor only

Temperature (oC) 650

Pressure (bar) 1

Heat Duty, Q (MJ/h) 22926.48

Reactor Volume (m3) 0.7600

Length of tubes (m) 5

Diameter of tubes (m) 0.0254

Number of tubes 300

The reactor modelled for this project at 650oC gave a maximum yield of hydrogen of 53.4 vol % as compared with the lab yield of 70 vol % of hydrogen stated by Barbarias et al

(2017)[24].

13

Separation Unit:

The effluent stream (4) goes through controller (CT-101) to maintain the outlet temperature, stream (5) passes through condenser and is cooled by the fresh water as it enters the separation unit. This unit consist of flash section and two component separators.

The flash removed high boiling components and recycle to convert unreacted and water. The stream (18) enters component separator for further purification.

The unit operations details are included in the appendix.

14

Fig 3.1 Process Flow Diagram of the production of hydrogen

Energy Balance and Utility Requirements

The general mass conservation equation, assuming plug flow is being considered for gas circulation in the reactor. The increase in the number of moles of the reactions is a function of the total molar flow rate, PT, that varies along the fluidized bed. The equation below shows the differential elements of the mass of the catalyst (dM) for component i.

dPi = d(PTXi) = PT ( dXi ) + Xi (dPT ) = (ri)0 dM dM dM dM where M is the mass of catalyst, Xi is the molar fraction of component i.

(ai)0 = ∑ (vi)j(aj)0

(aj)0 is the rate of reaction j at zero time and (vi)0 is the stoichiometric coefficient of component i in the reaction j.

To produce hydrogen, there is need to keep the temperature of the reactor at the gas phase so a combustor with natural gas as utility is used to supply the heat duty of 22,976.1 MJ/h.

The heat exchanger unit 5 functions as a condenser to cool the stream for separation. It uses

15 the cooling water and supplied a heat duty of 18,368.94 MJ/h likewise, the heat exchanger unit 6 utilizes fresh water and recycle water as utility to keep the stream from combustor at above 150oC in order to prevent condensation in the stack. The table below shows all the necessary utilities needed.

Table 3.2 : Utility cost for hydrogen production. Name Total Grass Utility Efficiency Actual Annual

Module Roots Used Usage Utility

cost ($) Cost ($) (MJ/h) Cost ($)

E101 713,096 870,000 Cooling 18300 58,000

water

E-102 400,000 520,000 Fresh 8470 26,600

water &

Recycle

water

H-101 2,480,000 3,530,000 Natural 0.9 222976 670,000

Gas

V-101 34,400 48,900 NA

Total 3,630,000 4,970,000 249,816 753,600

16

Table 3.3: Summary of Equipment Cost for Hydrogen Production Equipment Equipment No Module Cost ($) Grass Root

Description Cost($)

Reformer H-101 2,248,000 3,530,000

Vessel (Flash) V-101 34,400 48,900

Heat Exchanger E-101 713,096 870,000

Heat Exchanger E-102 400,000 520,000

Total 3,630,000 4,970,000

The table shows the cost of each equipment needed to produce hydrogen and installation cost. The costs are added to get the module cost and grass root cost. This is important because it a new chemical plant and other factors are being included so the grass root cost is $5 million. In addition to these costs, the catalyst and materials costs will also need to be factored in.

Economic Discussion and Market Analysis

According to NREL’s (National Laboratory) financial analysis using

H2FAST modelling tool. In 2018, a 180kg/day station without financial support from government when 10,500 FCEVs were projected in California would not attain a positive cash flow for life span of 20 years of the station, even if it sells $16/kg. If the same station with financial incentive from government opened in 2018, it will attain a positive cash flow as early as 2020, even if it sells $9.50/kg[28] The price of hydrogen in the market gives us the insight to where it is needed most. The average selling price of hydrogen fuel is $6/kg

[29]. This plant can produce 848kg/h of hydrogen from 50 metric ton/day of waste plastic

17 which mean $5,088/h. With these values, the sales of hydrogen will cover the operating cost and raw material cost. With the introduction of financial incentive to the public, waste plastic can be gathered without much difficulty. The following cost analysis is based on the selling prices of $6/kg hydrogen and easy access of the materials needed.

The facility has the following details:

 The Lang factor cost is approximately $6.6 million

 This process has a gross root cost of approximately $5 million and annual utility

cost of $0.75 million.

 Materials of construction are mostly carbon steel and stainless steel.

 Additional cost not included is cost of catalyst and raw materials cost

 If the plant produces 20 ton/day(878.6 kg/h) and the price of hydrogen is $6 /kg, it

gives us $126,518/day and $35.4 million/year

 With a rough estimate of fixed capital investment of about $20 million, The ROI

(Return on Investment) will be 75%. This makes the chemical plant economical

feasible and profitable.

Safety Consideration

The following safety measures have been taking into considering while designing the plant:

 Provision of proper PPE(Personal Protective Equipment) or ventilation, water spray

to control the spread because hydrogen is extremely flammable

 Compositions of all the streams are constantly monitored to avoid corrosion

 Piping is insulated if it can cause burns on contact.

Environmental Considerations are as follow:

18

 Waste streams exiting the plant: the utilities are recycled both onsite and offsite

 Best available control technology (BACT) compliance is met

 Carbon emission of 40,460 ton/year is captured during purification using absorber

and stripper or PSA(Pressure Swing Adsorption).

19

CHAPTER FOUR Conclusion

This work is an eye opener for the Government and individual to see avenue of creating jobs and opportunities in the society. It is avenue to improve our environment using waste plastic that has polluted the landfill and oceans as the raw materials in this project. In another view, introduction of, use of hydrogen fuel in the society, makes the environment a safe place to live.

The price of hydrogen will determine the profitability of the chemical plant. Generally, the market price of hydrogen depends on the region. Today, renewable hydrogen from electrolysis cost about $6/kilogram (kg). It is forecasted that by 2030, if costs of hydrogen production and distribution fall, hydrogen solutions will be a close competitor with low carbon alternatives[29].

The market price of the hydrogen is assumed to go higher when more countries start to adopt the use of hydrogen driven vehicles. They are all advocating for ‘green technology and green industry’.

In the future, it is highly recommended to research more in final product separation to get

99.9% pure hydrogen with zero carbon production by:

 Complying to the EPA regulations about CO2 emission, an incorporation of a well-

designed CO2 absorber or PSA (Pressure Swing Adsorption) to further purify

hydrogen and capture CO2.

 Evaluation of the hydrogen production lines should be accounted for to prioritize

ways to capture CO2.

20

We can also combat the challenges facing the plastic waste management by:

 Introduction of incentives: it could be in form of tax break, tax cut or monetary to

the any individual who provides a tons of waste plastic to a government or private

owned designated facility.

 Government can make a regulation to all plastic manufacturers that all their

products must be reusable.

 Provision of waste basket tagged ‘plastic’ to each house.

21

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Appendix

Table 6.1 Stream Properties of Streams (1-4).

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Table 6.2 Stream Properties of stream( 5-8).

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Table 6.3 Stream Properties of streams (9-12).

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Table 6.4 Stream Properties of streams (13-16)

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Table 6.5 Stream Properties of streams (17-18).

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Table 6.6: Furnace Reformer specification

REACTOR (V101): Plug Flow Function: Convert Hydrocarbons to hydrogen Materials Inlet Outlet Stream 3 4 Mass Flow (kg/h) 10,081.47 10,081.47 Breakdown (kg/h) Uneiscosane 1504.31 123.55 Hexanedecane 574.76 47.2 N-Decane 131.54 10.8 n-Propane 30.66 6.86 Methane 0.6249 0.32 Water 7839.44 3028.01 Hydrogen 0 847.92 Carbon Dioxide 0 5363.5 Carbon Monoxide 0 651.3 Nitrogen 0 0 0 0 Operating Conditions: Temperature (oC) 649.29 Pressure (bar) 1 Heat Duty (MJ/h) 22,929.20 Design Data: Construction material Carbon Steel Diameter of tubes(m) 0.0254 Weight (kg) 4168.76 Length of tubes(m) 5 Volume(m3) 0.76 Catalyst Ni Number of tubes 300 Catalyst weight (kg) 426 Purchase Cost $985,000 Bare Module Cost $2,100,000 Annual Utility Cost $67,000

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Table 6.7: Flash Drum specification

FLASH DRUM (V101) Function: Remove most of the water and unreacted hydrocarbons from S6 Materials Inlet Bottoms Overhead Stream 6 7 18 Phase MIX LIQUID VAPOR Mass Flow (kg/h) 10,081.51 1,464.65 8,616.85 Volumetric Flow Breakdown (kg/h) Uneiscosane 123.55 123.55 0 Hexanedecane 47.2 47.2 0 N-Decane 10.8 9.83 0.9 n-Propane 6.86 0.04 6.86 Methane 0.32 0 0.3 Water 3028.01 1283.9 1733.11 Hydrogen 847.92 0 847.92 Carbon Dioxide 5365.52 0.12 5365.39 Carbon Monoxide 651.3 0 651.3 Nitrogen 0 0 0 Oxygen 0 0 0 Operating Conditions: Temperature (oC) Pressure (bar) 1 Equilibrium Vapor-Liquid Equilibrium Design Data: Construction material Carbon Steel Diameter (m) 1.37 Weight (kg) 4168.76 Height(m) 1.9 Volume(m3) 3.53 Purchase Cost $7,150 Bare Module Cost $29,100 Annual Utility Cost

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Table 6.8: Heat Exchanger (E-101) specification

Heat Exchanger (E101) Block Type: Floating Head Shell and Tube Function: Cool stream 4 for flash separation using cooling water Shell: Inlet Outlet Stream 11 12 Temperature(oC) 33 100 Pressure (bar) 1 1 Tube Inlet Outlet Stream 5 6 Temperature(oC) 649 53.6 Pressure (bar) 1 1 Operating Conditions Shell Flow Rate(Kg/h) 7996.06 Tube Flow Rate(kg/h) 10081.51 Design Data: Construction material Stainless Steel Flow Direction Counter Current Number of Tubes 1396 Number of Tube Passes 1 Number of Shell Passes 1 Transfer Area (m2) 501 Cal. Stream Heat Duty MJ/h 8474.1074 Purchased Cost $268,000 Bare Module Cost $604,000 Annual Utility Cost $58,000

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Table 6.9: Heat Exchanger (E-102) specification

Heat Exchanger (E102) Block Type: Floating Head Shell and Tube Function: Heat stream 12 to make up steam for the feed using natural gas. Shell: Inlet Outlet Stream 11 12 Temperature(oC) 100 518.6 Pressure (bar) 1 1 Tube Inlet Outlet Stream 15 16 Temperature(oC) 702.9 150 Pressure (bar) 1 1 Operating Conditions Shell Flow Rate(Kg/h) 7996.06 Tube Flow Rate(kg/h) 12584.5 Design Data: Stainless Steel/ Carbon Construction material Steel Flow Direction Counter Current Number of Tubes 1396 Number of Tube Passes 1 Number of Shell Passes 1 Transfer Area (m2) 501 Cal. Stream Heat Duty MJ/h 8474.11 Purchased Cost $132,000 Bare Module Cost $339,000 Annual Utility Cost $26,600

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