DOCSLIB.ORG

Modelling of Naphtha Cracking for Olefins Production

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Modelling of Naphtha Cracking for Olefins Production Modelling of Naphtha Cracking for Olefins Production João Miguel Monteiro Marcos [email protected] Instituto Superior Técnico, Lisboa, Portugal December 2016 Abstract The production of ethylene and propylene from naphtha via thermal cracking is a cornerstone of the chemical industry. This process is carried out in furnaces operating at high temperature, and optimal operation of these furnaces is necessary to maintain profitability. In the present work, a mathematical model of a naphtha cracking furnace was developed in gPROMS®, in which the main focus was the development of a SRT-VI coil model. This furnace model was used to validate kinetics present in literature against typical data for naphtha cracking. A tuning of the implemented kinetics was carried out, by adding new components, new sets of reactions and tuning the kinetic parameters in the reaction scheme, leading to good predictions, having yield deviations of less than 5% for the main products (light olefins - ethylene and propylene) and around 15% for aromatics. Keywords: modelling, steam cracking, naphtha, ethane, propane, kinetics, furnace. 1. Introduction Hydrocarbon steam cracking is one of the production of polyethylene, ethylene oxide, vinyl most important processes in the petrochemical acetate, and ethylbenzene and ethylene industry, producing highly valuable olefins such as dichloride [3]. ethylene, propylene from lower value feedstocks, Propylene is considered a co-product of this which usually have fossil fuel origin, ranging from process, reporting 109 million tonnes in 2014. It is gaseous feedstocks, like ethane and propane to used for the production of polypropylene, liquid, heavier feedstocks, such as naphtha, gas propylene oxide, cumene and isopropanol [4]. oil and gas condensates. Naphtha is the most For the optimisation of an olefins plant, the widely used, due to availability, low cost and developing of predictive furnace models, capable potential for producing high yields of olefins [1]. of describing cracking and coking phenomena, Ethylene is the major product of a stream becomes essential, and will be the main focus of cracking unit. With a world production of around the current work. 1.48 million tonnes/year in 2014 [2], and an annual growth at an average rate of 4%, it is the largest volume building block, and it is mainly used for the 1 2. Background 600 − 860 ℃, which are maintained through heat The method for the production of olefins from transfer with a firebox, where fuel burners reach naphtha is through thermal hydrocarbon cracking temperatures between 1000 − 1200 ℃. The heat reactions, which occur in the presence of steam in transfer mechanism is mainly radiation. Due to the the radiant coil of the furnace, at high endothermicity of the cracking reactions, high temperatures ranging from 700℃ at the inlet of the heat fluxes are required (75 − 85 푘푊/푚2of coil) coil to 900℃ at the outlet. [1]. For the cracking of naphtha, and depending The cracking reactions occur via free-radical on the operating conditions (which heavily mechanisms, and for the cracking of naphtha, influence the severity of cracking), the product resulting in yields of ethylene between 25 − 35% stream is made up of (in 푤푡. %) 25 − 35 % of and propylene between 14 − 18% [1]. ethylene, 14 − 18 % of propylene, 4 − 6 % of butadiene as well as ~14 % of methane and 5 − 2.1 Steam Cracking process 10 % of aromatics, namely BTX. A simplified flowsheet of the steam cracking Typical cracking coil dimensions are usually process that be found in Figure 3. The cracking 40 − 90 푚 in length, diameters from3 − 20 푐푚. [1] furnace serves as the reactor and “heart” of the process, thus being the most important unit of the plant. It is comprised of two main sections: the furnace section and the radiant section, as seen in Figure 1. The hydrocarbon feed enters the furnace in the convection section, where it is pre-heated by heat exchange against flue gases. It is then mixed with dilution steam, up to ratios of Steam:Oil (푘푔푠푡푒푎푚/푘푔ℎ푦푑푟표푐푎푟푏표푛) of 0.25 − 0.40 for gaseous feed and 0.40 − 0.55 in the case of naphtha. This reduces hydrocarbon partial pressure, leading to reduced rates of coke formation (thus avoiding decreased heat transfer coefficients and increased pressure drops), being able to increase the run-time of the furnace. The Figure 1- Diagram a steam cracking furnace in a typical olefin plant. resulting mixture is further heated to temperatures of 500 − 680 ℃, which favour the cracking reactions. [1] [3] This mixture of feed and steam, in the gaseous state, enters the radiant section of the furnace, where radiant coils act as tubular reactors, submitting the hydrocarbons to cracking reactions for periods of 0.1 − 0.5 푠. This section of Figure 2- Industrial cracking coil. the furnace operates at temperatures between 2 Figure 3- Simplified flowsheet of the steam cracking process. After exiting the furnace, the resulting stream, To compress the cracked gas, a series of 4 to in the gaseous phase, and with a high content on 6 compression stages with inter-stage coolers is light olefins is subjected to a series of treatments used, allowing the cracked gas to reach pressures to remove condensates, water and other up to 35 bars, while maintaining temperatures undesired components before the fractionation below 100 ℃. The condensates, as well as water step. and other heavier components are removed The cracked gas then leaves the radiant coil during this cooling process, alongside with at 800 − 860 ℃ (COT), and is cooled during a 퐻2푆 and 퐶푂2, which are removed by contacting period of 0.02 − 0.1 푠 to 550 − 650 ℃ to prevent with an alkaline solution (acid gas removal). [1] [3] further cracking of valuable reaction products as The resulting gas needs to be dried in order well the formation of coke. This cooling process to remove water (up to < 1 푝푝푚), in order to occurs in the transfer-line exchangers (TLE), by proceed for the fractionation equipment. indirect quenching. Finally, the cracked and now purified gas is An oil quench follows, which is used to reduce chilled and separated into its product streams the temperature down to around 230 ℃. (ethylene, propylene, crude 퐶4 and pyrolysis Next, a primary fractionator (gasoline gasoline and gas oil), by means of a series of fractionator) is used in order to separate the distillation columns. pyrolysis fuel oil (heavier hydrocarbons) from the In order to further increase light olefins yield, main stream. hydrogenation reactions occur, in which To be further processed, the hydrocarbon acetylene, methylacetylene and propadiene are product stream is then cooled to near ambient converted to ethylene and propylene in catalytic temperature by means of water quench tower, in hydrogenation beds. [1] [3] which it contacts with a large descending water stream. 3 2.2 Steam cracking reactions In order to be able to have predictive models, It is widely accepted that the largest part of capable of describing the cracking reactions and gas phase hydrocarbon pyrolysis occurs through prediction product distribution, the need arises to a free radical mechanism, characterized by a vast develop kinetic models, which describe the number of species and reactions. cracking phenomena through a series of The kinetic mechanism is summarised by the reactions. In the current work, mechanistic models following reaction classes [5] [6]. will be used, based on schemes of free radicals. Two kinetic schemes (available in literature) for 1) Initiation and termination reactions the cracking of naphtha will be used: the scheme These reactions involve either the C-C bond described by Joo [7], comprising a total of 231 scission, forming two smaller radicals (Eq. 1a), or reactions between 79 chemical species up to 퐶9; a new bond (C-C or C-H) as two radicals come and the scheme described by Towfighi [8], together and produce a single molecule (1b). containing 150 reactions and involving 54 components up to 퐶 . ∗ ∗ 8 푅1 + 푅2 → 푅1 + 푅2 (1a) ∗ ∗ 푅1 + 푅2 → 푅1 + 푅2 (1b) 3. Implementation The current work was developed in gPROMS 2) Propagation reactions ProcessBuilder®, which was used for model After the initiation step, radical species development, flowsheeting and simulation. undergo a series of propagation reactions in An external physical property package was which keeping the reaction chain going. These used (Multiflash) as well as a stoichiometric matrix reactions can be of different types: compression scheme (LSKM). A. Hydrogen abstraction 3.1 Model Equations Smaller reactive radicals abstract a This section describes the model hydrogen atom from another molecule, creating equations in mathematical furnace model both a new molecule and new radicals. used in this work. The furnace is composed of ∗ ∗ 푅1 + 푅2 → 푅1 + 푅2 (2) several sub-models, which together describe all phenomena occurring in the furnace. B. Radical addition For the tube model, which is treated as a Radicals react with olefins, thus forming PFR, the mass balance is as follows (Eq. 5): less saturated compounds and a new radical. 푑 [푁 퐴] = 푀푊 퐴푟 (5) ∗ 푑푧 푖 푖 푖 푅1 + 푅2 = 푅3 → 푅1 − 푅2 − 푅3 (3) Where 푁 represents the mass flux for C. Radical isomerisation 푖 Responsible for the transfer of the active component , 퐴 is the cross-section area of the radical position within the molecule. tube, 푀푊 is the molecular weight of component and 푟푖 is the overall reaction rate (rate of ∗ ∗ 푅1 − 푅2 − 푅3 − 푅4 ↔ 푅1 − 푅2 − 푅3 − 푅4 (4) formation/disappearance) of component . 4 The reaction rate of a given reaction j, 푟푗 can be related with are the forward and backwards reaction constants for a given reaction j, 푘푓,푗 and 푘푏,푗 , respectively, and the component molar concentration of the reactants and products by (Eq. 6): 푟푗 = 푘푓,푗 ∏ 퐶푟푒푎푐 − 푘푏,푗 ∏ 퐶푝푟표푑 (6) The energy balance is as shown in (Eq.6): 푑 Figure 4 - Schematic of the modelled SRT-VI coil.
Load more

Recommended publications
  • Naphtha Catalytic Cracking Process Economics Program Report 29K
    ` IHS CHEMICAL Naphtha Catalytic Cracking Process Economics Program Report 29K December 2017 ihs.com PEP Report 29K Naphtha Catalytic Cracking Michael Arne Research Director, Emerging Technologies IHS Chemical | PEP Report 29K Naphtha Catalytic Cracking PEP Report 29K Naphtha Catalytic Cracking Michael Arne, Research Director, Emerging Technologies Abstract Ethylene is the world’s most important petrochemical, and steam cracking is by far the dominant method of production. In recent years, several economic trends have arisen that have motivated producers to examine alternative means for the cracking of hydrocarbons. Propylene demand is growing faster than ethylene demand, a trend that is expected to continue for the foreseeable future. Hydraulic fracturing in the United States has led to an oversupply of liquefied petroleum gas (LPG) which, in turn, has led to low ethane prices and a shift in olefin feedstock from naphtha to ethane. This shift to ethane has led to a relative reduction in the production of propylene. Conventional steam cracking of naphtha is limited by the kinetic behavior of the pyrolysis reactions to a propylene-to-ethylene ratio of 0.6–0.7. These trends have led producers to search for alternative ways to produce propylene. Several of these— propane dehydrogenation and metathesis, for example—have seen large numbers of newly constructed plants in recent years. Another avenue producers have examined is fluid catalytic cracking (FCC). FCC is the world’s second largest source of propylene. This propylene is essentially a byproduct of refinery gasoline production. However, in recent years, an effort has been made to increase ethylene and propylene yields to the point that these light olefins become the primary products.
    [Show full text]
  • Cracking (Chemistry)
    Cracking (chemistry) In petrochemistry, petroleum geology and organic chemistry, cracking is the process whereby complex organic molecules such as kerogens or long-chain hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carbon-carbon bonds in the precursors. The rate of cracking and the end products are strongly dependent on the temperature and presence of catalysts. Cracking is the breakdown of a large alkane into smaller, more useful alkenes. Simply put, hydrocarbon cracking is the process of breaking a long chain of hydrocarbons into short ones. This process requires high temperatures.[1] More loosely, outside the field of petroleum chemistry, the term "cracking" is used to describe any type of splitting of molecules under the influence of heat, catalysts and solvents, such as in processes of destructive distillation or pyrolysis. Fluid catalytic cracking produces a high yield of petrol and LPG, while hydrocracking is a major source of jet fuel, Diesel fuel, naphtha, and again yields LPG. Contents History and patents Cracking methodologies Thermal cracking Steam cracking Fluid Catalytic cracking Hydrocracking Fundamentals See also Refinery using the Shukhov cracking References process, Baku, Soviet Union, 1934. External links History and patents Among several variants of thermal cracking methods (variously known as the "Shukhov cracking process", "Burton cracking process", "Burton-Humphreys cracking process", and "Dubbs cracking process") Vladimir Shukhov, a Russian engineer, invented and patented the first in 1891 (Russian Empire, patent no. 12926, November 7, 1891).[2] One installation was used to a limited extent in Russia, but development was not followed up. In the first decade of the 20th century the American engineers William Merriam Burton and Robert E.
    [Show full text]
  • Polycyclic Aromatic Hydrocarbons and Petroleum Industry
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Columbia University Academic Commons 76905_ch81 p1236-1246.qxd 10/4/06 9:32 PM Page 1236 MARKED SET 81 Polycyclic Aromatic Hydrocarbons and Petroleum Industry Steven Stellman, PhD, MPH Tee L. Guidotti, MD, MPH, DABT CHEMISTRY AND STRUCTURES chrysene, dibenz(a,h)anthracene, fluoranthene, fluo- rene, indeno(1,2,3-cd)pyrene, naphthalene, phenan- The term polycyclic aromatic hydrocarbons (PAHs) threne, pyrene) that includes a group of seven PAHs (in generally refers to a group of chemical compounds bold) that are probable human carcinogens. Figure 81.1 consisting of carbon and hydrogen atoms arranged as illustrates structures of key PAHs. The best-known PAH is planar compounds whose principal structural feature benzo(a)pyrene (BaP), due to its early identification in is fused rings. Their nomenclature has evolved over coal tar and later use as a model compound for investigat- many decades and is complex. A comprehensive listing, ing the carcinogenic properties of tobacco smoke. including traditional synonyms and chemical struc- tures, is given by Sander and Wise (1). PAHs are produced during the incomplete combustion SOURCES OF POLYCYCLIC of organic material and are among the most ubiquitous AROMATIC HYDROCARBONS environmental pollutants. The combustion processes that IN THE ENVIRONMENT release PAHs invariably produce a variety of compounds, and in fact, it is difficult or impossible to ascribe health PAHs enter the environment through both natural and effects in humans to particular members of the PAH manmade processes. The principal natural sources of family.
    [Show full text]
  • Catalytic Dehydrogenation of Ethane: a Mini Review of Recent Advances and Perspective of Chemical Looping Technology
    catalysts Review Catalytic Dehydrogenation of Ethane: A Mini Review of Recent Advances and Perspective of Chemical Looping Technology Danis Fairuzov, Ilias Gerzeliev, Anton Maximov and Evgeny Naranov * Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Leninskiy Prospect, 29, 119991 Moscow, Russia; [email protected] (D.F.); [email protected] (I.G.); [email protected] (A.M.) * Correspondence: [email protected] Abstract: Dehydrogenation processes play an important role in the petrochemical industry. High selectivity towards olefins is usually hindered by numerous side reactions in a conventional crack- ing/pyrolysis technology. Herein, we show recent studies devoted to selective ethylene production via oxidative and non-oxidative reactions. This review summarizes the progress that has been achieved with ethane conversion in terms of the process effectivity. Briefly, steam cracking, catalytic dehydrogenation, oxidative dehydrogenation (with CO2/O2), membrane technology, and chemical looping are reviewed. Keywords: ethylene; ethane; dehydrogenation; cracking; membrane technology; chemical looping 1. Introduction Citation: Fairuzov, D.; Gerzeliev, I.; Ethylene is one of the most critical intermediates in the petrochemical industry and Maximov, A.; Naranov, E. Catalytic the global demand for this chemical is shown in Figure1; it is currently produced through Dehydrogenation of Ethane: A Mini the steam cracking of light hydrocarbon derivatives, mainly ethane and naphtha [1–3]. Review of Recent Advances and Ethylene complexes operate in 57 countries of the world. There are 215 ethylene producing Perspective of Chemical Looping facilities operating in the world. The operators of these complexes are about 100 companies, Technology. Catalysts 2021, 11, 833. and the largest are ExxonMobil, SABIC, DowDuPont [4–6].
    [Show full text]
  • Steam Cracking: Chemical Engineering
    Steam Cracking: Kinetics and Feed Characterisation João Pedro Vilhena de Freitas Moreira Thesis to obtain the Master of Science Degree in Chemical Engineering Supervisors: Professor Doctor Henrique Aníbal Santos de Matos Doctor Štepánˇ Špatenka Examination Committee Chairperson: Professor Doctor Carlos Manuel Faria de Barros Henriques Supervisor: Professor Doctor Henrique Aníbal Santos de Matos Member of the Committee: Specialist Engineer André Alexandre Bravo Ferreira Vilelas November 2015 ii The roots of education are bitter, but the fruit is sweet. – Aristotle All I am I owe to my mother. – George Washington iii iv Acknowledgments To begin with, my deepest thanks to Professor Carla Pinheiro, Professor Henrique Matos and Pro- fessor Costas Pantelides for allowing me to take this internship at Process Systems Enterprise Ltd., London, a seven-month truly worthy experience for both my professional and personal life which I will certainly never forget. I would also like to thank my PSE and IST supervisors, who help me to go through this final journey as a Chemical Engineering student. To Stˇ epˇ an´ and Sreekumar from PSE, thank you so much for your patience, for helping and encouraging me to always keep a positive attitude, even when harder problems arose. To Prof. Henrique who always showed availability to answer my questions and to meet in person whenever possible. Gostaria tambem´ de agradecer aos meus colegas de casa e de curso Andre,´ Frederico, Joana e Miguel, com quem partilhei casa. Foi uma experienciaˆ inesquec´ıvel que atravessamos´ juntos e cer- tamente que a vossa presenc¸a diaria´ apos´ cada dia de trabalho ajudou imenso a aliviar as saudades de casa.
    [Show full text]
  • Olefins from Biomass Intermediates: a Review
    catalysts Review Review OlefinsOlefins fromfrom BiomassBiomass Intermediates:Intermediates: AA ReviewReview 1 1,2, VasilikiVasiliki Zacharopoulou Zacharopoulou1 andand AngelikiAngeliki A.A. LemonidouLemonidou 1,2,** 1 Department of Chemical Engineering, Aristotle University of Thessaloniki, University Campus, 1 Department of Chemical Engineering, Aristotle University of Thessaloniki, University Campus, Thessaloniki 54124, Greece; [email protected] 54124 Thessaloniki, Greece; [email protected] 2 Chemical Process Engineering Research Institute (CERTH/CPERI), P.O. Box 60361 Thermi, 2 Chemical Process Engineering Research Institute (CERTH/CPERI), P.O. Box 60361 Thermi, Thessaloniki 57001, Greece 57001 Thessaloniki, Greece * Correspondence: [email protected]; Tel.: +30‐2310‐996‐273 * Correspondence: [email protected]; Tel.: +30-2310-996-273 Received: 16 November 2017; Accepted: 19 December 2017; Published: Received: 16 November 2017; Accepted: 19 December 2017; Published: 23 December 2017 Abstract:Abstract: Over the last decade, increasing demand for olefinsolefins and theirtheir valuablevaluable productsproducts hashas promptedprompted researchresearch onon novelnovel processesprocesses andand technologiestechnologies forfor theirtheir selectiveselective production.production. As olefinsolefins are predominatelypredominately dependent on fossil resources, their production is limited by thethe finitefinite reservesreserves and the associated economic and environmental concerns.concerns. The need for alternative routes for
    [Show full text]
  • Hydrocarbons Thermal Cracking Selectivity Depending on Their Structure and Cracking Parameters
    Master in Chemical Engineering Hydrocarbons Thermal Cracking Selectivity Depending on Their Structure and Cracking Parameters Thesis of the Master’s Degree Development Project in Foreign Environment Cláudia Sofia Martins Angeira Erasmus coordinator: Eng. Miguel Madeira Examiner in FEUP: Eng. Fernando Martins Supervisor in ICT: Doc. Ing Petr Zámostný July 2008 Acknowledgements I would like to thank Doc. Ing. Petr Zámostný for the opportunity to hold a master's thesis in this project, the orientation, the support given during the laboratory work and suggestions for improvement through the work. i Hydrocarbons Thermal Cracking Selectivity Depending on Their Structure and Cracking Parameters Abstract This research deals with the study of hydrocarbon thermal cracking with the aim of producing ethylene, one of the most important raw materials in Chemical Industry. The main objective was the study of cracking reactions of hydrocarbons by means of measuring the selectivity of hydrocarbons primary cracking and evaluating the relationship between the structure and the behavior. This project constitutes one part of a bigger project involving the study of more than 30 hydrocarbons with broad structure variability. The work made in this particular project was focused on the study of the double bond position effect in linear unsaturated hydrocarbons. Laboratory experiments were carried out in the Laboratory of Gas and Pyrolysis Chromatography at the Department of Organic Technology, Institute of Chemical Technology, Prague, using for all experiments the same apparatus, Pyrolysis Gas Chromatograph, to increase the reliability and feasibility of results obtained. Linear octenes with different double bond position in hydrocarbon chain were used as model compounds. In order to achieve these goals, the primary cracking reactions were studied by the method of primary selectivities.
    [Show full text]
  • Naphtha Catalytic Cracking for Propylene Production by FCCU
    Naphtha Catalytic Cracking for Propylene Production by FCCU Christopher Dean - HIGH Olefins Technology Services LLC Coking and CatCracking Conference New Delhi, India – October 2013 Purpose (Objective) • To present and discuss producing propylene (C3=) by catalytic cracking paraffinic naphtha utilizing Fluid Catalytic Cracking processes 2 Contents- Covering 3 Points • Why Propylene from FCCU’s ? • Naphtha Feedstocks – Supply Balances • Naphtha Catalytic Cracking Processes • FCC Catalytic Processes • Traditional Steam Cracking (Comparison) 3 TYPICAL FCC Paraffinic Naphtha 4 Benefits • MOTOR GASOLINE • PETROCHEMICAL FEEDSTOCKS • Propylene (C3=) TODAY & FUTURE PLANNING • Minimizing to no gasoline production from FCC • Additional Focus • Light Olefins (Ethylene & Butylenes) • Aromatics 5 Why Propylene from FCCU’s ? • Europe, North America (US) refineries are facing profitability challenges • Gasoline demand declining both areas • Middle Distillates (Diesel) markets increasing both areas • European surplus gasoline export markets are declining • US lighter shale crudes, “tight oil” use is increasing that produce more naphtha and less diesel • Asia market is for distillates and petrochemical feedstocks • Large Middle East, Asia, India and South America are building large integrated Refinery/ Petrochemical 7 Complexes Petrochemicals Opportunities Produced by Steam Cracking Main Building Blocks Ethane & Liquid Feeds Naphtha Reformers • Olefins - Two Main Blocks • Ethylene • Propylene Secondary Source Produced by FCC’s • Aromatics • Benzene •
    [Show full text]
  • Effects of Secondary Reaction of Primary Volatiles on Oil/Gas Yield and Quality from Oil Shale Pyrolysis
    ISSN: 2638-1974 International Journal of Petrochemistry and Research Research Article Open Access Effects of Secondary reaction of Primary Volatiles on Oil/gas Yield and Quality from Oil Shale Pyrolysis Yuming Zhang1*, Rongxuan Linghu1, Lei Huang1, Liang Zhang1, Guogang Sun1 and Shu Zhang2* 1State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, P.R.China 2College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, Jiangsu, P.R. China Article Info Abstract *Corresponding authors: The reaction behaviors of primary volatiles from oil shale pyrolysis were investigated Yuming Zhang using a two-stage reactor under different in-situ thermal reaction conditions. The secondary State Key Laboratory of Heavy Oil Processing reaction parameters, such as conversion temperature, reaction atmosphere and residence China University of Petroleum-Beijing time, were studied for their effects on the pyrolysis oil/gas yield and quality. The results Beijing 102249, P.R.China showed that the reaction temperature had a profound influence on the oil and gas yield, Tel: +86-15001296129 as indicated by the fact that the pyrolyzed shale oil and gas yield reduced by 15% (mass) E-mail: [email protected] and 20% (mass) respectively, with the temperature of 2nd stage reactor increasing from Shu Zhang ° ° College of Materials Science and 600 C to 650 C. Comparing with a nitrogen atmosphere, the liquid oil yield could enhance Engineering by 5% when steam was added as the reaction atmosphere in the second stage, and the Nanjing Forestry University corresponding oil was mainly concentrated in the gasoline and diesel distillations, that is, Nanjing 210037 boiling point <350°C.
    [Show full text]
  • Naphtha Steam Cracking (NSC) Unit Optimization the Use of Robust On-Line Analyzer Technology for the Real-Time Optimization of Steam-Cracking Furnace Operation
    — ABB MEASUREMENT & ANALYTICS | WHITE PAPER Naphtha Steam Cracking (NSC) unit optimization The use of robust on-line analyzer technology for the real-time optimization of steam-cracking furnace operation This white paper illustrates how the fast response times and excellent repeatability of on-line FT-NIR and other analyzers can be used to provide complete real-time data for the optimization of naphtha steam-cracking furnaces. Measurement made easy — First, we need to look at the background: why real-time also generate added-value co-products such as Refinery optimization of the steam-cracking furnace is so propylene, butenes (for butadiene production) necessary and what analytical tools exist to help. and a high aromatics content pygas product. This allows for operation of the steam-cracker in campaign Ethylene production runs at around 175 M tons mode, the better to tune product spectrum per year, the vast majority of which is produced to market opportunity. by steam-cracking light hydrocarbons – ethane where it is readily and cheaply available, liquid feeds Dr. Michael B. Simpson such as naphtha or, less commonly, gas oil where Industry Manager, Refining and Petrochemicals it is more advantageous. The use of naphtha as ABB Measurement & Analytics a feedstock has significant additional advantages where the end-customer market is dynamic in terms of demand and pricing, since naphtha feedstocks 2 NSC UNIT OPTIMIZATION | White Paper CH (off-gas) Acid gas 4 Quench/ fractionate Compression XXXX H S/CO 2 2 Methanator HC feed H Dryers 2 Demethanizer
    [Show full text]
  • Department Chemical Industries Major Course Title Chemistry Code
    University: Foundation Of Technical Republic of Iraq Institutes The Ministry of Higher Education Institute: Kirkuk Tech. Ins. & Scientific Research Department: Chemistry Industries Lecturer name: Dr. Moneeb T. Salman Academic Status: Qualification: Ph.D. Department Chemical Industries Major Course Title Chemistry Code CHEM1 Course Instructor Dr. Moneeb T. Salman Course Description: Semester 1 The course involves the study of atomic structure, modern periodic table, chemical bonds and formulae, states of matter, analytical chemistry, chemical reactions, acids and Contact Th. bases and salts, fundamentals of organic chemistry, Hours 1 extraction, chromatography and polymers. (Hour/week) Pr. 2 Total 3 General Goal: The student will become familiar with the fundamentals of chemistry such as: atomic structure, periodic table, fundamentals of analytical and organic chemistry, extraction, chromatography and polymers. Behavioural Objectives: The student will be able to: · Do a general revision of atomic structure and electronic distribution · Study the modern periodic table · Know how to build the chemical formulae of molecules and compounds and their nomenclature and the type of bonds between atoms · Know the three states of matter and their application to some daily observations · Identify acids, bases and salts · Chemical reactions and chemical equilibrium · Know the fundamentals of organic chemistry 1 Topics The importance of chemistry, its common branches. Atomic structure and electronic distribution. Periodic table. Chemical formulae of molecules and compounds, nomenclature and the types of bonds. Acids, bases and salts. Chemical reactions and chemical equilibrium. Fundamentals of analytical chemistry, qualitative & quantitative chemical analysis, standard solution and indicators. Units of concentration Fundamentals of organic chemistry. Extraction. Chromatography. Polymers. Course Instructor Dr.
    [Show full text]
  • Olefins from Conventional and Heavy Feedstocks: Energy Use in Steam Cracking and Alternative Processes
    Energy 31 (2006) 425–451 www.elsevier.com/locate/energy Olefins from conventional and heavy feedstocks: Energy use in steam cracking and alternative processes Tao Ren*, Martin Patel, Kornelis Blok Department of Science, Technology and Society, Faculty of Chemistry, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands Received 1 June 2004 Abstract Steam cracking for the production of light olefins, such as ethylene and propylene, is the single most energy- consuming process in the chemical industry. This paper reviews conventional steam cracking and innovative olefin technologies in terms of energy efficiency. It is found that the pyrolysis section of a naphtha steam cracker alone consumes approximately 65% of the total process energy and approximately 75% of the total exergy loss. A family portrait of olefin technologies by feedstocks is drawn to search for alternatives. An overview of state-of-the-art naphtha cracking technologies shows that approximately 20% savings on the current average process energy use are possible. Advanced naphtha cracking technologies in the pyrolysis section, such as advanced coil and furnace materials, could together lead to up to approximately 20% savings on the process energy use by state-of-the-art technologies. Improvements in the compression and separation sections could together lead to up to approximately 15% savings. Alternative processes, i.e. catalytic olefin technologies, can save up to approximately 20%. q 2005 Elsevier Ltd. All rights reserved. 1. Introduction Steam cracking1 is the most energy-consuming process in the chemical industry and globally uses approximately 8%2 of the sector’s total primary energy use, excluding energy content of final * Corresponding author.
    [Show full text]