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Chemical engineers design, construct and operate plants
Chemical engineers design, construct and operate plants

Chemical engineering is the branch of engineering that deals with the application of physical science (e. Engineering is the Discipline and Profession of applying technical and scientific Knowledge and Physical science is an encompassing term for the branches of Natural science and Science that study non-living systems in contrast to the biological sciences g. chemistry and physics), with mathematics, to the process of converting raw materials or chemicals into more useful or valuable forms. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Physics (Greek Physis - φύσις in everyday terms is the Science of Matter and its motion. Mathematics is the body of Knowledge and Academic discipline that studies such concepts as Quantity, Structure, Space and Materials are physical Substances used as inputs to production or Manufacturing. A chemical substance is a Material with a definite chemical composition. In addition to producing useful materials, chemical engineering is also concerned with pioneering valuable new materials and techniques, an important form of research and development. The phrase research and development (also R and D or more often R&D) according to the Organization for Economic Co-operation and Development, refers A person employed in this field is called a chemical engineer. In the field of Engineering, a chemical engineer is the profession in which one works principally in the Chemical industry to convert basic raw materials into a variety

Chemical engineering largely involves the design and maintenance of chemical processes for large-scale manufacture. Chemical engineers in this branch are usually employed under the title of process engineer. The development of the large-scale processes characteristic of industrialized economies is a feat of chemical engineering, not chemistry. Indeed, chemical engineers are responsible for the availability of the modern high-quality materials that are essential for running an industrial economy.

Contents

Chemical Engineering Timeline

Main article: History of chemical engineering

In 1824, French physicist Sadi Carnot, in his “On the Motive Power of Fire”, was the first to study the thermodynamics of combustion reactions in steam engines. Chemical engineering as a discipline is a little over one hundred years old Nicolas Léonard Sadi Carnot (1 June 1796 &ndash 24 August 1832 was a French Physicist and Military engineer who in his 1824 Reflections In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. In the 1850s, German physicist Rudolf Clausius began to apply the principles developed by Carnot to chemicals systems at the atomic to molecular scale. Rudolf Julius Emanuel Clausius (Born Rudolf Gottlieb, January 2, 1822 &ndash August 24, 1888) was a German Physicist [1] During the years 1873 to 1876 at Yale University, American mathematical physicist Josiah Willard Gibbs, the first to be awarded a Ph. Josiah Willard Gibbs ( February 11, 1839 &ndash April 28, 1903) was an American theoretical Physicist, Chemist D. in engineering in the U. S. , in a series of three papers, developed a mathematical-based, graphical methodology, for the study of chemical systems using the thermodynamics of Clausius. In 1882, German physicist Hermann von Helmholtz, published a founding thermodynamics paper, similar to Gibbs, but with more of an electro-chemical basis, in which he showed that measure of chemical affinity, i. In Chemical physics and Physical chemistry, chemical affinity can be defined as electronic properties by which dissimilar Chemical species are capable of e. the “force” of chemical reactions, is determined by the measure of the free energy of the reaction process. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called In Thermodynamics, the term thermodynamic free energy refers to the amount of work that can be extracted from a System, and is helpful in Engineering Following these early developments, the new science of chemical engineering began to develop. The following timeline shows some of the key steps in the development of the science of chemical engineering:[2]

Applications

Chemical engineering is applied in the manufacture of a wide variety of products. The chemical industry proper manufactures inorganic and organic industrial chemicals, ceramics, fuels and petrochemicals, agrochemicals (fertilizers, insecticides, herbicides), plastics and elastomers, oleochemicals, explosives, detergents and detergent products (soap, shampoo, cleaning fluids), fragrances and flavors, additives, dietary supplements and pharmaceuticals. The chemical industry comprises the companies that produce industrial chemicals Petrochemicals are chemical products made from raw materials of Petroleum or other Hydrocarbon origin Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products An elastomer is a Polymer with the property of Elasticity. The term which is derived from elastic polymer, is often used interchangeably with the term Closely allied or overlapping disciplines include wood processing, food processing, environmental technology, and the engineering of petroleum, glass, paints and other coatings, inks, sealants and adhesives. Wood Processing is a form of a doing that is when you take a perfectly good piece of wood and you make it into a new piece Wood products includ Paper, from pulp

Example

To show the difference between laboratory chemistry and industrial chemical engineering, consider a simple one-step reaction between two reagents R1 and R2 to give a product P and waste W. The reaction may be represented R1 + R2 = P + W. A solvent S and possibly a catalyst C may be required, and it may need to be heated to speed the reaction. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Catalysis is the process in which the rate of a Chemical reaction is increased by means of a Chemical substance known as a catalyst

A specific example would be the synthesis of aspirin by the reaction of salicylic acid (R1) with acetic anhydride (R2) in solvent water (S) and in the presence of catalyst phosphoric acid (C). Aspirin, or acetylsalicylic acid (ASA (əˌsɛtɨlsælɨˌsɪlɨk ˈæsɨd is a Salicylate drug, often used as an Analgesic to relieve Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula Acetic anhydride is the Chemical compound with the formula (CH3CO2O Phosphoric acid, also known as orthophosphoric acid or phosphoric(V acid, is a mineral (inorganic acid having the Chemical formula Aspirin is the product P, and acetic acid (W) is also formed.

In the laboratory 5 grams of R1 (a solid) are added to 120 ml of water in a flask. 5 ml of R2 (a liquid) are added plus 0. 5 ml of phosphoric acid solution, and the flask is heated in a water bath. The contents are agitated by swirling the flask or with a laboratory stirrer and heated under reflux for about an hour.

The material is allowed to cool down and crystals of aspirin are formed, which may be filtered off, and perhaps recrystallized. A good yield would be 5 to 6 grams. The remaining solution is poured down the sink.

Now consider an industrial process in which we replace grams with tonnes.

Firstly suitable storage (say for two weeks of production) must be provided for the raw materials. In this case R1 is a solid and would be put in a storage silo; R2 is a corrosive liquid, combustible and sensitive to water, so would need a closed tank of resistant material. A silo is a structure for storing bulk materials. Silos are used in Agriculture to store grain (see Grain elevators or fermented feed A means of transport to the reactor must be provided, such as a screw conveyor for the solid R1 and a pump and pipes for liquid R2. Screw conveyors have been a popular material handling mechanism throughout history For information on Wikipedia project-related discussions see WikipediaVillage pump. Chemical engineers would calculate the sizes and power requirements and specify suitable materials. Similar arrangements must be made for the solvent S and the catalyst C. In this case, water is the solvent, but ordinary tap water would not be good enough, so there will be a separate process to clean the water.

The reactor is now to contain 120 tonnes of water and the other ingredients, so cannot be swirled. An agitator must be designed and its power consumption calculated to give the necessary mixing. Heating and cooling are considered free in the laboratory, but not in industry. The chemical engineers must first calculate the amount of heat to be added and removed, then design suitable methods to do this, perhaps by passing steam through an outer jacket of the vessel to heat. They will probably decide to pump the reacted mixture to another vessel with a cooler, then to a filter. The solid will then go to further equipment to dissolve, crystallize and filter again, giving perhaps 5. 5 tonnes of aspirin, which will be dried and placed in suitable storage, which must also be designed. (The drying process uses significant amounts of energy. )

However, there is about 125 tonnes of waste which cannot be just poured down the drain. It will contain some unreacted R1 and about 3 tonnes of W, which must be recovered and recycled. (In this case, W can be converted to R2 in another reactor. ) The catalyst may be recovered, or made harmless by a chemical reaction before disposal. Thus there will be another set of equipment to save the cost of wasting chemicals and to protect the environment. Solvents other than water are generally recycled by distillation, but water is also re-used and recycled as far as economically feasible. Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture

This process may run as a batch process, where reactors are filled and emptied discharging their contents through the plant upon completion. Alternatively the process may be run as a continuous process, where the reaction precursors are fed through the plant at a fixed rate. The choice of continuous or batch is dependent upon a combination of reaction kinetics, the desired amount of product and the economics of the plant's operation and would be decided during the design phase of the plant. Chemical kinetics, also known as reaction kinetics is the study of rates of chemical processes

Overview

Chemical engineers design processes to ensure the most economical operation. This means that the entire production chain must be planned and controlled for costs. A chemical engineer can both simplify and complicate "showcase" reactions for an economic advantage. Using a higher pressure or temperature makes several reactions easier; ammonia, for example, is simply produced from its component elements in a high-pressure reactor. On the other hand, reactions with a low yield can be recycled continuously, which would be complex, arduous work if done by hand in the laboratory. It is not unusual to build 6-step, or even 12-step evaporators to reuse the vaporization energy for an economic advantage. In contrast, laboratory chemists evaporate samples in a single step.

The individual processes used by chemical engineers (eg. distillation or filtration) are called unit operations and consist of chemical reactions, mass-, heat- and momentum- transfer operations. Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture Filtration is a mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases by interposing a medium to fluid flow through which the fluid In Chemical engineering and related fields a unit operation is a basic step in a Process. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called Mass transfer is the phrase commonly used in engineering for physical processes that involve molecular and convective transport of Atoms and Molecules In thermal physics, heat transfer is the passage of Thermal energy from a hot to a colder body Fluid dynamics is the sub-discipline of Fluid mechanics dealing with fluid flow: Fluids ( Liquids and Gases in motion Unit operations are grouped together in various configurations for the purpose of chemical synthesis and/or chemical separation. In Chemistry, chemical synthesis is purposeful execution of Chemical reactions in order to get a product, or several products In Chemistry and Chemical engineering, a separation process is used to transform a Mixture of substances into two or more distinct products Some processes are a combination of intertwined transport and separation unit operations, (e. g. reactive distillation). Reactive distillation is a process where the chemical Reactor is also the Still.

Three primary physical laws underlying chemical engineering design are conservation of mass, conservation of momentum and conservation of energy. The law of conservation of mass/matter, also known as law of mass/matter conservation (or the Lomonosov - Lavoisier law says that the Mass of In Classical mechanics, momentum ( pl momenta SI unit kg · m/s, or equivalently N · s) is the product In Physics, the law of conservation of energy states that the total amount of Energy in an isolated system remains constant and cannot be created although it may The movement of mass and energy around a chemical process are evaluated using mass balances and energy balances, laws that apply to discrete parts of equipment, unit operations, or an entire plant. A mass balance (also called a material balance is an application of Conservation of mass to the analysis of physical systems In doing so, chemical engineers must also use principles of thermodynamics, reaction kinetics and transport phenomena. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Chemical kinetics, also known as reaction kinetics is the study of rates of chemical processes The first edition of Transport Phenomena was published in 1960 two years after having been preliminarily published under the title Notes on Transport Phenomena based The task of performing these balances is now aided by process simulators, which are complex software models (see List of Chemical Process Simulators) that can solve mass and energy balances and usually have built-in modules to simulate a variety of common unit operations. This is a list of software used to simulate the material and energy balances of chemical processing plants

Modern chemical engineering

The modern discipline of chemical engineering encompasses much more than just process engineering. Chemical engineers are now engaged in the development and production of a diverse range of products, as well as in commodity and specialty chemicals. A chemical substance is a Material with a definite chemical composition. These products include high performance materials needed for aerospace, automotive, biomedical, electronic, environmental and space and military applications. This article is about the field of research and industry for the corporation see The Aerospace Corporation Aerospace comprises the Modern automotive engineering is a branch of Vehicle engineering, incorporating elements of mechanical, electrical, electronic, software Biomedical engineering ( BME) is the application of engineering principles and techniques to the medical field Electronics refers to the flow of charge (moving Electrons through Nonmetal conductors (mainly Semiconductors, whereas electrical Environmental engineering is the application of Science and Engineering principles to improve the environment (air water and/or land resources A military is an Organization authorized by its Nation to use force usually including use of Weapons in defending its Country (or by attacking Examples include ultra-strong fibers, fabrics, adhesives and composites for vehicles, bio-compatible materials for implants and prosthetics, gels for medical applications, pharmaceuticals, and films with special dielectric, optical or spectroscopic properties for opto-electronic devices. A textile is a flexible material comprised of a network of natural or artificial Fibres often referred to as thread or Yarn. Glue or adhesive is a compound that adheres or bonds two items together Biocompatibility is related to the behavior of Biomaterials and in that it is a peculiar word because it would seem that are at least two opposing uses of the same term In Medicine, a prosthesis (plural prostheses) is an Artificial extension that replaces a missing Body part. A gel (from the lat gelu &mdashfreezing cold ice or gelatus &mdashfrozen immobile is an apparently solid jelly-like material formed from a A drug, broadly speaking is any chemical substance that when absorbed into the body A dielectric is a nonconducting substance ie an insulator. The term was coined by William Whewell in response to a request from Michael Faraday. Spectroscopy was originally the study of the interaction between Radiation and Matter as a function of Wavelength (λ Additionally, chemical engineering is often intertwined with biology and biomedical engineering. Foundations of modern biology There are five unifying principles Biomedical engineering ( BME) is the application of engineering principles and techniques to the medical field Many chemical engineers work on biological projects such as understanding biopolymers (proteins) and mapping the human genome. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl The Human Genome Project (HGP was an international Scientific research project with a primary goal to determine the sequence of chemical base pairs which make up DNA

Related fields and topics

Today, the field of chemical engineering is a diverse one, covering areas from biotechnology and nanotechnology to mineral processing. Biotechnology is Technology based on Biology, especially when used in Agriculture, Food science, and Medicine. Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular Mineral processing, otherwise known as mineral dressing is the practice of beneficiating valuable minerals from their Ores Industrial mineral treatment processes usually combine

See also

References

  1. ^ Mechanical Theory of Heat – Nine Memoirs on the development of concept of "Entropy" by Rudolf Clausius [1850-1865]
  2. ^ History of Chemical Engineering – at North Carolina State University (and in general). Biochemical engineering is a branch of Chemical engineering or Biological engineering that mainly deals with the design and construction of unit processes that Biomedical engineering ( BME) is the application of engineering principles and techniques to the medical field Molecular engineering is any means of manufacturing Molecules It may be used to create on an extremely small scale most typically one at a time new molecules which may not Biotechnology is Technology based on Biology, especially when used in Agriculture, Food science, and Medicine. The word ceramic is derived from the Greek word κεραμικός ( keramikos) Chemical process modeling is a Computer modeling technique used in Chemical engineering process design. Chemical technologists and technicians provide technical support and services or may work independently in Chemical engineering, chemical and biochemical research In Chemical engineering, chemical reactors are vessels designed to contain Chemical reactions The design of a chemical reactor deals with multiple aspects of Computational fluid dynamics (CFD is one of the branches of Fluid mechanics that uses Numerical methods and algorithms to solve and analyze problems that involve Distillation Design is a book which provides complete coverage of the design of industrial Distillation columns for the petroleum refining, Electrochemistry is a branch of Chemistry that studies Chemical reactions which take place in a Solution at the interface of an electron conductor Environmental engineering is the application of Science and Engineering principles to improve the environment (air water and/or land resources Fluid dynamics is the sub-discipline of Fluid mechanics dealing with fluid flow: Fluids ( Liquids and Gases in motion In thermal physics, heat transfer is the passage of Thermal energy from a hot to a colder body Mass transfer is the phrase commonly used in engineering for physical processes that involve molecular and convective transport of Atoms and Molecules Materials Science or Materials Engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of Science and Microfluidics deals with the behavior precise control and manipulation of Fluids that are geometrically constrained to a small typically sub-millimeter scale Mineral processing, otherwise known as mineral dressing is the practice of beneficiating valuable minerals from their Ores Industrial mineral treatment processes usually combine Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular See also Nature The natural environment, commonly referred to simply as the environment, is a terminology that is comprised of all living and A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Process control is a Statistics and Engineering discipline that deals with Architectures mechanisms and Algorithms for controlling Process design is the design of processes for desired physical and/or chemical transformation of materials The global pulp and paper industry is dominated by North American ( United States, Canada) Northern European ( Finland, Sweden Semiconductor device fabrication is the process used to create chips the Integrated circuits that are present in everyday Electrical and electronic In Chemistry and Chemical engineering, a separation process is used to transform a Mixture of substances into two or more distinct products In Chemistry and Chemical engineering, a separation process is used to transform a Mixture of substances into two or more distinct products Crystallization is the (natural or artificial process of formation of solid Crystals precipitating from a homogeneous --> identical Solution Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture Membrane operation or membrane process is considered like a unit operation in Chemical engineering. Textile engineering ( TE) or textile technology deals with the application of scientific and Engineering principles to the design and control In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " The first edition of Transport Phenomena was published in 1960 two years after having been preliminarily published under the title Notes on Transport Phenomena based In Chemical engineering and related fields a unit operation is a basic step in a Process. Unit Operations of Chemical Engineering, first published in 1956 is one of the oldest chemical engineering textbooks still in widespread use The American Institute of Chemical Engineers ( AIChE) is a Professional organization for chemical engineers. In the field of Engineering, a chemical engineer is the profession in which one works principally in the Chemical industry to convert basic raw materials into a variety Food and Bioprocess Technology an International Journal is an international Peer reviewed journal published by Springer, a leading international renowned publisher Contemporary Food Engineering is a book series published by CRC Press / Taylor & Francis, a leading international renowned publisher ECE is IChemE’s online journal launched in May 2006 at ACHEMA This is a list of notable Chemical engineers, people who studied or practiced Chemical engineering. This is the list of chemical engineering societies in the world Process design is the design of processes for desired physical and/or chemical transformation of materials This is a list of software used to simulate the material and energy balances of chemical processing plants
  3. ^ Glasgow Herald July 18, 1888 and September 5, 1888
  4. ^ N. A. Peppas (1989) One Hundred Years of Chemical Engineering Kluwer ISBN 0792301455
  5. ^ 2007 Indiana Economic Development Corporation Life Sciences Report
  6. ^ Colin Duvall and Sean F, Johnston Scaling Up: The Institution of Chemical Engineers and the Rise of a New Profession Kluwer Academic Publishers (2000)

Further reading

External links

Octave Levenspiel is an Emeritus professor of Chemical engineering at Oregon State University. The Open Directory Project ( ODP) also known as dmoz (from directory

Dictionary

chemical engineering

-noun

  1. The branch of engineering that deals with the design, construction and operation of industrial process plants, and the physical, chemical and biological processes to create substances or energy in a useful and economic form.
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