Chemical process industries reactors

Induction heating is used to heat steel reactor vessels in the chemical process industry (5). The heat produced in the walls is conducted to the material within. Multisectioned cods are used to provide controlled heat input to the process material as it passes through the reactor. Figure 6 illustrates a cross section of such a typical installation. 

K. G. Webley, "Induction Heating of Steel Reactor Vessels," Chemical Process Industry Symposium, AlCHE, Philadelphia, Pa., June 5—8,1978. 

Zirconium is used as a containment material for the uranium oxide fuel pellets in nuclear power reactors (see Nuclearreactors). Zirconium is particularly usehil for this appHcation because of its ready availabiUty, good ductiUty, resistance to radiation damage, low thermal-neutron absorption cross section 18 x 10 ° ra (0.18 bams), and excellent corrosion resistance in pressurized hot water up to 350°C. Zirconium is used as an alloy strengthening agent in aluminum and magnesium, and as the burning component in flash bulbs. It is employed as a corrosion-resistant metal in the chemical process industry, and as pressure-vessel material of constmction in the ASME Boiler and Pressure Vessel Codes. 

As the previous ehapter discussed nuelear power reactor operation and how to perform a PSA on it, this chapter attempts to apply a similar framework to chemical processing. The problem is the diversity of chemical processing that blurs the focus. This chapter begins by showing that accidents in the chemical process industry cost lives and dollars. Descriptions of deadly chemical accidents arc presented to show the chain of sequences that were involved to suggest how their PSA may be structured. Background on selected hazardous chemical process is presented followed by descriptions of how their PSA have structured. The chapter concludes by applying FTAPSUIT to a pressure vessel rupture analysis. 

There is a close kinship between the chemical process industry and the nuclear electric power industry. In tact once the physics of nuclear reaction was established the rest is chemistiy and hc.it ii an.sfer. The word "reactor" is from chemistry for the location the reaction takes place.. nuclear reactor consists of a vessel in which a nuclear reaction heats water to make steam to drive a turbine o generate electricity. Thus the primary components are pipes, valves, pumps heat exchangers, and water purifiers similar to the components found in a chemical plant. Following the success of WASH-1400, PSA was used to analyze the chemical proce.ssmg of nuclear fuel and. aste preparation for disposal. 

I am a physicist who switched to nuclear engineering for my Ph D. My introduction to PSA was as an original participant in the Reactor Safety Study in 1972. Material for this book was first gathered in 1974 for a workshop on what to expect in WASH-1400 (the results of the Reactor Safety Study). Materials were gathered over the years for EPRI, Savannah River Laboratory, and other workshops. A culmination was in 1988 with "Probabilistic Risk Assessment in the Nuclear Power Industry" with Robert Hall as coauthor. This book updates these materials and adds material on PSA in the chemical process industry. I prepared the material for printing using a word processor... 

There are two basic types of packed-bed reactors those in which the solid is a reactant and those in which the solid is a catalyst. Many e.xaniples of the first type can be found in the extractive metallurgical industries. In the chemical process industries, the designer normally meets the second type, catalytic reactors. Industrial packed-bed catalylic reactors range in size from units with small tubes (a few centimeters in diameter) to large-diameter packed beds. Packed-bed reactors are used for gas and gas-liquid reactions. Heat transfer rates in large-diameter packed beds are poor and where high heat transfer rates are required, Jluidized beds should be considered. ... 

In the chemical process industry molybdenum has found use as washers and bolts to patch glass-lined vessels used in sulphuric acid and acid environments where nascent hydrogen is produced. Molybdenum thermocouples and valves have also been used in sulphuric acid applications, and molybdenum alloys have been used as reactor linings in plant used for the production of n-butyl chloride by reactions involving hydrochloric and sulphuric acids at temperatures in excess of 170°C. Miscellaneous applications where molybdenum has been used include the liquid phase Zircex hydrochlorination process, the Van Arkel Iodide process for zirconium production and the Metal Hydrides process for the production of super-pure thorium from thorium iodide. 

Continuous Flow Reactors—Stirred Tanks. The continuous flow stirred tank reactor is used extensively in chemical process industries. Both single tanks and batteries of tanks connected in series are used. In many respects the mechanical and heat transfer aspects of these reactors closely resemble the stirred tank batch reactors treated in the previous subsection. However, in the present case, one must also provide for continuous addition of reactants and continuous withdrawal of the product stream. 

Continuous flow stirred tank reactors are widely used in the chemical process industry. Although individual reactors may be used, it is usually preferable to employ a battery of such reactors connected in series. The effectiveness of such batteries depends on the number of reactors used, the sizes of the component reactors, and the efficiency of mixing within each stage. 

Polymerization processes represent an extremely important aspect of the chemical processing industry. Since many of the properties of polymeric materials are markedly affected by their average molecular weight and their molecular weight distribution, the design of reactors for polymerization processes offers many opportunities for the use of the principles presented earlier in this chapter. 

Every student who has just read that this course will involve descriptions of industrial process and the history of the chemical process industry is probably already worried about what will be on the tests. Students usually think that problems with numerical answers (5.2 liters and 95% conversion) are somehow easier than anything where memorization is involved. We assure you that most problems will be of the numerical answer type. However, by the time students become seniors, they usually start to worry (properly) that their jobs will not just involve simple, weU-posed problems but rather examination of messy situations where the boss does not know the answer (and sometimes doesn t understand the problem). You are employed to think about the big picture, and numerical calculations are only occasionally the best way to find solutions. Our major intent in discussing descriptions of processes and history is to help you see the contexts in which we need to consider chemical reactors. Your instructor may ask you to memorize some facts or use facts discussed here to synthesize a process similar to those here. However, even if your instructor is a total wimp, we hope that reading about what makes the world of chemical reaction engineering operate wiU be both instmctive and interesting. 

Health, Safety, and Accident Management in the Chemical Process Industries, Ann Marie Flynn and Louis Theodore Plantwide Dynamic Simulators in Chemical Processing and Control, William L. Luyben Chemical Reactor Design, Peter Harriott Catalysis of Organic Reactions, edited by Dennis G. Morrell Lubricant Additives Chemistry and Applications, edited by Leslie R. Rudnick... 

Tanks are used in innumerable ways in the chemical process industry, not only to store every conceivable liquid, vapor, or solid, but also in a number of processing applications. For example, as well as reactors, tanks have served as the vessels for various unit operations such as settling, mixing, crystallization (qv), phase separation, and heat exchange. Herein the main focus is on the use of tanks as liquid storage vessels. The principles outlined, however, can generally be applied to tanks in other applications as well as to other pressure-containing equipment. 

In this book the chemical plant is focused upon. Therefore, the present chapter emphasizes chemical reactors for the chemical process industry. But it should be made clear that structured packings and catalysts also have a large potential in consumer products. Chemical reactors form the heart of a (petro-)chemicals production plant. Given the large variety of plants it is no surprise that a wide variety of chemical reactors are used. Catalytic reactors can be roughly divided into random and structured reactors. It is useful to start with a summary of the major basic concerns (apart from high activity, selectivity, etc.) for catalytic reactors ... 

The flow through porous media of emulsions, foams, and suspensions can be important in a number of applications ranging from fixed-bed catalytic reactors in the chemical process industries, to flows through soil environments, to flow in underground reservoirs. To understand the flow of dispersions in porous media one needs a knowledge not only of the properties of the dispersion, but also of the porous medium. Pore characterization itself has been reviewed elsewhere [30,416]. 

Knowledge of these types of reactors is important because some industrial reactors approach the idealized types or may be simulated by a number of ideal reactors. In this chapter, we will review the above reactors and their applications in the chemical process industries. Additionally, multiphase reactors such as the fixed and fluidized beds are reviewed. In Chapter 5, the numerical method of analysis will be used to model the concentration-time profiles of various reactions in a batch reactor, and provide sizing of the batch, semi-batch, continuous flow stirred tank, and plug flow reactors for both isothermal and adiabatic conditions. 

The various types of reactors employed in the processing of fluids in the chemical process industries (CPI) were reviewed in Chapter 4. Design equations were also derived (Chapters 5 and 6) for ideal reactors, namely the continuous flow stirred tank reactor (CFSTR), batch, and plug flow under isothermal and non-isothermal conditions, which established equilibrium conversions for reversible reactions and optimum temperature progressions of industrial reactions. 

Blending of chemical reactants is a common operation in the chemical process industries. Blend time predichons are usually based on empirical correlations. When a competitive side reaction is present, the final product distribution is often unknown until the reactor is built. The effects of the position of the feed stream on the reaction byproducts are usually unknown. Also, the scale-up of chemical reactors is not straightforward. Thus, there is a need for comprehensive, physical models that can be used to predict important information like blend time and reaction product distribution, especially as they relate to scale and feed position. 

EPA. 1993a. Chemicals affected by Subpart RRR. Standards of Performance for New Stationary Sources. U.S. Environmental Protection Agency. Subpart RRR - Standards of Performance for Volatile Organic Compound (VOC) Emissions from the Synthetic Organic Chemical Manufacturing Industry Reactor Processes. Code of Federal Regulations. 40 CFR 60.707. 

Monoliths allow the efficient use of small catalyst particles, such as zeolites, and are remarkably flexible with respect to their catalyst inventory. Multifunctional reactor operations such as reactive stripping and distillation are challenging applications that are not far away. They have several potential applications in oil refineries, in fhe chemical process industry, and for consumers. The industrial application of the monolithic stirrer reactor as alternatives to many slurry-t)q5e reactors in fine chemisfry has the greatest potential as a new practice involving monolithic catalysts. 

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