Do you all really know ???
Chemical Engineering is a relatively new field and was formally
established in the late 1800's. Originally, Chemical Engineers were
formed to help spend less time and less money creating industrial
chemicals, which were, because of the industrial revolution, needed,
in large quantities. The first so-called "Chemical Engineers" were
either Mechanical Engineers who knew some about chemical
process equipment; Chemical Plant Foremen who had worked a
lifetime in the plant and had learned from their experiences instead of
schooling; or Applied Chemists who had researched and had
knowledge of large scale chemical reactions.
Here are some highlights from the early history of Chemical
Engineering:
1959: John Glover, who designed the first mass-transfer tower, is
often considered to be the first Chemical Engineer. At this time,
nitrate was commonly used in reactions. Chile was the only available
source for nitrate, and therefore it was very expensive to import into
Britain. John Glover's tower absorbed extra nitrate, which was
instead being burned off, and recycled it. This "Glover Tower"
became a standard among chemical plants in Britain at that time.
1880: George Davis, a Britain, founded the Society for Chemical
Engineers, which failed.
1887: George Davis presented a series of 12 lectures on Chemical
Engineering at Manchester Technical School. His information was
criticized for being common, everyday English know-how, since it
was designed around operating practices used by British chemical
industries. At this time, however, in the United States, this information
helped jump-start "new" ideas in the Chemical Industry, as well as
spark Chemical Engineering programs at several universities.
1888: The first Chemical Engineering curriculum ever began at
theMassachusetts Institute of Technology (MIT). This four year
BS program, designed by Lewis Norton, combined Mechanical
Engineering and industrial chemistry in order to fulfill the rising needs
of the Chemical Industry.
1892: University of Pennsylvania also developed a Chemical
Engineering program.
1894: Tulane University became the first southern school, and also
the third American school, to offer a program in Chemical
Engineering.
1901-1904: George Davis wrote a "Handbook of Chemical
Engineering,"which had over 1000 pages about unit operations,
now considered to be part of the base of all modern-day Chemical
Engineering.
1915: Arthur D Little recognized that filtration, heat exchange,
distillation, and other assorted processes which were used in
different industries were the same. This idea was called "Unit
Operations," and later lead to the integrated curriculum of today. He
stressed the idea of Unit Operations to distinguish Chemical
Engineering from other science and engineering disciplines.
Chemical Engineers were the first to deal with the products instead of
the mechanical process, and also to study the entire underlying
process instead of just one reaction. Unit Operations were the tool
showing the uniqueness and worth of Chemical Engineers to
American chemical manufacturers.
1932: The American Institute of Chemical Engineers (AIChE) was
formed. They were the first group to evaluate and accredit different
Chemical Engineering departments across America. During their first
few years, they gave 14 accreditations to various American
universities. The AIChE still exists, both nationwide and at UMass.
Why did chemical engineering emerge in America
instead of Germany?
As a scientific productive activity, engineering associates closely with natural science
on the one hand and industry on the other. The America’s industrial structures and
academic institutions influenced the emergence of chemical engineering. The science-
oriented characteristic of chemical engineering in turn affected the development of
industrial structures, especially the rapid rise of a competitive petrochemical industry.
Chemical engineering and its beginningChemical engineering is quite peculiar among
the many branches of engineering. Other branches – civil, mechanical, electrical, aerospace
– are mainly applied physics. Chemical engineering is unique in integrating chemistry with
physics to investigate systematically industrial processes of chemical production.
Biochemistry is, alongside genetics, a major strand of molecular biology. Molecules, the
transformation of which is the fort of chemistry, are ideal building blocks on the nanometer
scale. Chemical engineering occupies a strategic position in the Big Things of the twenty-first
century: biotechnology and nanotechnology. It is well prepared for the challenges, partly
because from its inception it has adopted the open spirit of science, developed principles
susceptible to modified generalization and ready to jump on new knowledge to make it
productive. (Its ranks boast the highest percentage of PhDs than any other branch of
engineering in the United States).
Historians generally agree that chemical engineering was developed by the
Americans in the beginning of the twentieth century. By that time, organic chemistry was
almost a century old, and inorganic chemistry, counting from Antoine Lavoisier’s pioneering
work in the 1780s, even older. Industries for inorganic chemicals were widespread. Organic
chemicals were more complicated, but industries using them to make dyestuffs,
pharmaceuticals, and other products were quite advanced. Why did chemical engineering
come so late?
The lucrative organic chemicals industry was dominated by Germany. Its dyestuffs
firms, the first to realize the importance of maintaining a technological edge, established the
world’s first industrial research laboratories. Industrial researchers cooperated closely with
staffs of graduate schools, another institution pioneered by the Germans. Together they
made Germany the world leader in research, chemistry, and chemical industry, attracting
students and professionals frommany other countries. The three American who founded
chemical engineering, William Walker, Warren Lewis, and Arthur D. Little, had all studied in
Germany. http://www.creatingtechnology.org/eng/chemE.pdf 1When, back home, the
Americans were struggling to development the contents for this new branch of engineering,
the Germans invented and industrialized the Haber-Bosch process to synthesize ammonia
and produce synthetic fertilizer commercially. The Haber-Bosch process, winner of two
Nobel Prizes, is even today acknowledged as one of the crowning achievements in chemical
engineering. Yet it was not the work of chemical engineers; Fritz Haber was a chemist, Carl
Bosch a mechanical engineer. Cooperation between chemists and mechanical engineers
was the standard practice in Germany. Its prowess was proved by thriving industries.
Why didn’t the Germans develop chemical engineering? They surely had the brains.
What did the Americans find wanting in prevailing practices? What advantages did chemical
engineering bring? What new technologies did it bring? To try to answer these questions
we have to examine the industrial structures in the two counties as well as the technical
contents of chemical engineering itself. Products and processes of production
What purposes does chemical engineering serve? To understand its functions, we
must distinguish between a product and the process of its production. An automobile is a
product, mass production a process. Consumers, who come into contact with products only,
seldom think about production processes. Without efficient processes, however, they
would not be offered such great varieties of products at such affordable prices. Product and
process both require engineering, but different kinds of engineering. In chemistry it may be
confusing, because chemical reactions are usually called processes. We will not use this
term and reserve “process” for production process on the industrial scale.Students in
chemistry classes shake a test tube or stir a beaker over a flame to speed up a chemical
reaction. Industrial plants cannot simply shake or stir a thousand-liter tank over a furnace,
not because it is too heavy but because it is too dangerous. Heat transportation and
distribution is much more difficult in large containers because of their relatively small
surfaceto-volume ratios, and uneven distribution in a tank of chemical reactants can end in a
deadly explosion.
To scale up a chemical reaction from test-tube to industrial level requires a lot of
knowledge and effort. This is apparent in the Haber-Bosch process. Haber’s method for
synthesizing ammonia required temperatures up to 500°C and pressures up to 1000
atmospheres. Because such high pressure and temperature were enormously difficult to
attain on the industrial scale, his invention might have remained a laboratory curiosity.
Fortunately, BASF, armed with the world’s first industrial R&D facility, invested heavily in
developing processes for high volume production. The complexity of scale-up was
acknowledge by the Nobel Prize awarded Bosch, who headed the scaling-up project, (Haber
had got his already). In production processes chemical engineering found its niche. But the
question remains: Why did the Germans left it to the Americans? To answer this question,
let us take a look at the structures of chemical industry in the two countries.
http://www.creatingtechnology.org/eng/chemE.pdf 2Chemical industries and engineering
Germany
● economy of scope
● fine chemicals: dyestuffs, drugs
137,000s in thousands of dyes
● advanced science, small volume
● product innovation → chemistry
● chemist & mechanical engineer
● industrial R&D → proprietary
1827 Liebig’s Lab. at Giessen
1860s Technische Hochschule
Höchst, Bayer, BASF
1877 BASF’s Main Laboratory
1880s physical chemistry
1899 Doktor-Ingenieure
1908 Haber: ammonia synthesis
1911 Bosch: ammonia production
USA
● economy of scale
● heavy chemicals: soda, petroleum 2,250,000 tones of sulfuric acid
● capital intensive, high volume
● production process → engineering
● chemical engineer
● university R&D → open science
1861 MIT
1888 Chemical engineering course
1908 Am. Inst. of Chemical Engineers
1915 Little: unit operations
1923 Walker & Lewis: Principles of Ch.E.
1929 Ch.E. research group in DuPont
1920- petroleum refining
1940- petrochemical
Sophisticated products and scientific research Chemicals come in great varieties,
even without counting plastics and synthetic fibers, which did not exist at the historical time
at issue. Most chemical do not reach consumers but are used up in manufacturing
processes, such as bleaching agents in the textile and paper industries. They roughly fall into
two classes. Heavy chemicals such as acid or soda are consumed by industry in enormous
volume. Fine chemicals such as dyes and drugs are greater in variety and more complicated
in structures, but are consumed in smaller amounts.
The German industry mainly specialized in fine chemicals. These high-tech, high-
value products required sophisticated chemistry to design and technical personnel to market.
To synthesize novel dyes required advanced chemistry and ample scientific research. The
dyes firms were keen on product design, on making dyes for all colors of the rainbow. They
were also keen to develop novel marketing techniques that helped their customers to use
these sophisticated dyes on fashionable fabrics. However, they were not too keen to
improve the efficiency of production processes. They produced thousands of different dyes,
but the amount of each dye was small, typically a hundred tons or so. For such small
volumes, scaling up was rather easy and could readily be handled by teams of chemists and
mechanical engineers. If the production processes they designed were less than maximally
efficient, the little waste was easily absorbed in the fat profit margin of high-value products.
When they saw opportunities for novel products with high-volume demands, the
Germans could mobilize their technical capacity in special projects to develop production
processes, which they http://www.creatingtechnology.org/eng/chemE.pdf 3kept proprietary.
This they did for the Haber-Bosch process for synthetic ammonia and fertilizer. But these
were singular cases. For their core business of fine chemicals, they did not see the need for
developing a discipline dedicated to efficient production processes. High volume
productions and scientific engineering The American industry was mainly for heavy
chemicals. These low-tech, low-value commodities required little if any science to design.
But they were produced in huge volumes.
America produced more than two million tons of sulphuric acid alone in 1913. High
volumes implied large plants with demanding scaling up. Furthermore, the razor-thin profit
margins of these commodities made the smallest waste painful. These industrial
characteristics called for efficient production processes, not merely for this or that plant or
product, but industry wide. The call was heeded not by industrialists but by academics:
Walker and Lewis of MIT and their consultant friend, Little. Their answer was superior
engineering based on scientific approaches.
The heavy chemicals industry already existed for over a century, during which
industrial processes were developed mainly by cut and try. By trial and error, industrial
chemists had developed many chemical processes and built many plants. Industrial
chemistry constituted a distinctive branch of chemistry. Its textbooks were like cookbooks
that offered catalogs of recipes. They described the techniques and listed the equipment for
each process separately, treating the procedures for one process as special to it and not
applicable to other processes. Tedious and repetitive, they showed the trees but gave no
hint about the forest. Lack of general principles hindered adaptation of procedures.
Knowledge acquired in industrial practices was locked into specific processes and not
accumulated. New processes were developed by time consuming cut and try. As the wheel
was invented anew for each process, technology progressed but slowly.
Not content with a catalog of industrial processes, Walker, Lewis, and Little
proceeded like natural scientists, only their phenomenon, chemical processing, is manmade.
They examined many existing chemical processes and abstract their general form. At the
heart of industrial chemical processing are chemical reactions, but they alone are not
sufficient. They are accompanied by physical mechanisms such as thermodynamic and fluid
dynamics, which distribute heat and bring ingredients into proper contact to ensure smooth
reaction. Chemical and physical mechanisms interact in intricate ways, but ways that exhibit
certain patterns, which the pioneering chemical engineers set themselves to extract.
A generic process involves preparation of raw materials, chemical reaction under
controlled conditions, separation of products, recycle byproducts, and disposal of wastes.
Each stage engages certain basic building blocks called “unit operations,” for instance
emulsification, filtration, distillation. And the same unit operations occur in many processes.
The chemical engineers introduce a general conceptual framework for thinking about
chemical processes, delineated the general operations, very much like natural scientists do
to natural phenomena. The result is a new science, chemical engineering science. As the
science developed over the decades, chemical engineers go deeper into the underlying
mechanisms. They developed http://www.creatingtechnology.org/eng/chemE.pdf
4mathematical theories, so that they can calculate and predict the performance of
processing plants without expensive experimentation.
Scientific engineering confers great economic advantages. Plants and raw materials
account for a much higher percentage of costs in chemical industries than in other
manufacturing, where labor costs are higher. Capital costs, much of it lies in financing, are
especially high for high volume productions, where they can consume up to one half of
product revenues. Tinkering and modifying expensive plants, which delay operation and
boost financial costs, are doubly unwelcome. High capital costs put a premium on the ability
to understand operating principles in the planning and design stage, which is a goal of
chemical engineering.
Let us pause to ask: Why not the British? We have been comparing the American
and German industries, but the British industry was similar to the American. Britain was
among the first to establish a heavy chemicals industry, and after an initial success, lost the
competition on fine chemicals. In fact, chemical engineering was first envisioned by the
British George Davis, whose pioneering ideas the Americans acknowledged. As an industrial
consultant and inspector, he visited a great variety of chemical processing plants, perceived
certain common factors, and tried to spell them out. His effort frizzled in Britain but his
dream was eventually fulfilled in America. Why? Such questions are best left to historians. I
can only guess that academic and government attitudes played a role. To develop a
discipline emphasizing general principles was more suited to universities than commercial
firms, which would be happier to develop specific processes that could be patented. The
major British universities, disdainful of “ungentlemanly” pursuits, were less than enthusiastic
to provide technical education.
This was often cited as a reason for Britain’s relative technological and economical
decline since the mid nineteenth century. By comparison, the atmosphere in America was
more open-minded and pragmatic. If its colonial universities had shared the British
snobbishness, they were put to competitive pressure in 1862 by the Morrill Land Grant
College Act, which gave government lands to colleges that offered courses in “agricultural
and the mechanic arts.” Among the universities the Act helped was Massachusetts Institute
of Technology, the nursery of chemical engineering. To answer a question raised, it may be
well to compare chemical engineering with another American innovation, industrial
engineering that facilitated mass production of mainly mechanical products such as cars.
Fabrication and assembly of mechanical products are labor intensive. Shortage of labor,
especially skilled labor, in America forced Americans to automate manufacturing processes
and develop assembly of interchangeable parts from early days.
Trying to substitute human workers by machines, industrial engineering focused on
worker-machine interfaces, such as the time-motion study well known to historians. In
contrast to the mechanical industries, the chemical industry is more capital intensive than
labor intensive, and chemical engineering addressed only physical processes. Furthermore,
the materials handled in chemical processing are mostly fluids, which are more susceptible
to mathematical representation and generalization than mechanical pieces that come in
infinite varieties of specific shapes. The style of chemical engineering is quite different from
that of industrial engineering. However, the differences seem to be determined more by the
technical characteristics of the industrial works at hand than by local cultural fashions.
From engineering science to new industries Reciprocal relations exist among the
structure of knowledge in an engineering discipline, the structure of natural phenomena it
understands and utilizes, and the structure of industrial and social needs it serves. German
engineering has always been formidable. Mechanical engineers such as Bosch were trained
on the job in the chemical industry. Their expertise was not systematically articulated but
was locked in their persons. The technology they developed remained mostly a corporate
property. It is “localized” knowledge not suitable for globalization.
In America, chemical engineering was developed by university professors keen on
education. Their knowledge was systematically represented for students who could go out
to work anywhere. It is a science open to generalization and adaptation. Armed with
scientific understanding, American chemical engineers were able to develop processes for
new chemical reactions rapidly. A triumph was the war-time production of penicillin, in
which processes were extended from chemistry to biochemistry. Another was the
development of fluidized bed for Houndry catalytic cracking in petroleum refinery. MIT
collaborated closely with Standard Oil of New Jersey to develop the process, educated
students on industrial sites, and advanced chemical engineering principles simultaneously as
they built the pilot plant. The story continues. The hydrocarbons contained in crude oil are
raw material for many organic chemicals. Today, most plastics, resins, synthetic fibers,
ammonia, methanol, and organic chemicals are manufactured with oil or natural gas as
feedstock. They are called petrochemicals, and there are thousands of them.
Manufacturing of each requires a different process, and the availability of chemical
engineering science played a crucial role in the almost overnight mushrooming of the
petrochemical industry after World War II. Specific chemical processes can be kept
proprietary, general principles cannot. Engineers formed consultant firms, many of which
performed their own R&D. These firms assumed the burden of design, development,
construction, and even personnel training. They delivered turnkey plants designed to the
specification of clients, thus reduced the technological barrier of entry. This was a novel
industrial structure, resulting in a highly open and competitive petrochemical industry. The
practice was copied worldwide
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