Paradigm Shifts in Chemical Engineering

1. Paradigm Shifts in Chemical Engineering Subject Code: CH8201 Subject Name : principles of Chemical Engineering Unit -V ADWINJOSE P Assistant Professor MSEC-Kilakarai

2. A new profession “Chemical Engineering” • From its beginning chemical engineering was tailored to fulfill theneeds of the chemical industry which, in the USA, was mostly based on derived feedstocks. Competitionbetween manufacturers was brutal, and all strove to be the "low cost producer." However, to stay ahead of the pack chemical plants had to be optimized. This necessitated things such as; continuously operating reactors (as opposed to batch operation), recycling and recoveryof unreacted reactants, and cost effective purification of products. These advances in-turn required plumbing systems (for which traditional chemists where unprepared) and detailed physical chemistry knowledge (unbeknownst to mechanical engineers). The new chemical engineers were capable of designing and operating the increasingly complex chemical operations which were rapidly emerging.

3. Paradigm: a pattern or model Paradigmis a constellation that defines a profession and an intellectual discipline • Firm theoretical foundations, triumphant applications to solve important problems • Universities agree on core subjects taught to all students, standard textbooks and handbooks, accreditation of degrees • Professional societies and journals • Organize research directions - what is a good research problem, and what are legitimate methods of solution?

4. Chemical engineering paradigms Pre-paradigm - engineers with no formal education 1. The first paradigm - Unit Operations, 1923 2. The second paradigm - Transport Phenomena, 1960 3. The third paradigm - ?

5. Pre-paradigm • Fire (300,000 BC) as the first chemical technology • Led to pyro-technologies: cooking, pottery, metallurgy, glass, reaction engineering • Chemical technology as empirical art, with no reliable scientific foundation or formally educated engineers. • Ecole des Ponts et Chausee, 1736, first modern engineering school.

6. The first paradigm • Arthur D. Little, industrialist and chair of visiting committee of chemical engineering at MIT, wrote report in 1908 “Unit Operations should be the foundation of chemical engineering” • First textbook Walker-Lewis-McAdams “Principles of Chemical Engineering” 1923

7. The first paradigm: early success • Became • core of chemical engineering curriculum, unit operations, stoichiometry, thermodynamics • principle to organize useful knowledge • inspiration for research to fill in the gaps in knowledge • Effective in problem solving • graduates have a toolbox to solve processing problems in oil distillation, petrochemical, new polymers

8. The first paradigm: later stagnation • World War II creation of new technologies by scientists without engineering education: atomic bomb, radar. • Engineering students needed to master new concepts and tools in chemistry and physics. • Unit Operations no longer created streams of exciting new research problems that were challenging to professors and students, and useful in industry.

9. The second paradigm • First textbook “Transport Phenomena” by Bird-Stewart-Lightfoot, 1960, based on kinetic theory of gases

10. The second paradigm • Textbook by Amundson “Mathematical Methods in Chemical Engineering”, (1966). • A new burst of creative research activities. • American chemical industry dominated world, DuPont and Exxon content to recruit academically educated graduates, willing to teach them technology.

11. The second paradigm: early success • The Engineering Science movement became dominant in the US, and was taught at all the leading universities. • AIChE accreditation requires differential equations, transport phenomena. • Research funding agencies and journals turn their backs on empirical and qualitative research as “old fashioned”.

12. Chemical Engineering: New Directions? • Phasing out of formerly successful products: tetra-ethyl lead, DDT, cellophane, freon or CFC. • End of the parade of new polymers: celluloid, bakelite, nylon, kevlar. • To attract the best students, the lure of new products to enhance lives - laptop computers, cellular phone and internet. • Cost-cutting and environmental protection is no match for glamorous new products. • We need to give chemical engineers the intellectual toolbox, to innovate exciting new products that people will learn to love.

13. Product Engineering: a third paradigm? • Product engineering is innovation and design of useful products that people want • 1. Define a product, study the customers & needs • 2. Understand property-structure • 3. Design and innovate the product