Overview of Chemical Industry

  

What is Chemical Engineering?

Before getting into our mainstream topic, let's try to understand what is chemical engineering. There are many definitions given by great scholars to this field, however first lets start with the simple one. Basically, it is the process of producing chemicals on LARGE SCALE. Remember the term LARGE SCALE is very important. Though this is not the technical definition, it’s the easiest one and can be understood by anyone. Now, what distinguishes a chemist from a Chemical Engineer?

Chemist performs the experiment on small scale in a lab. That is, he will take ‘x’ grams of A and ‘y’ grams of B and mix it in a test tube and may be he will shake it and heat it on a bunsen burner.  Now, if we want to produce the same chemical on Large Scale then we need to take ‘x’ and ‘y’ in tones and say we take a batch reactor. Now how to shake this big rector? That’s where CH Engineer comes in context. It’s engineer’s duty to find what to do now. Thus, stirrer is used to mix and also there are many parameters which should be looked upon while designing the stirrer too. Again to heat it or to remove the heat we need Heat Transfer (Heat Exchangers, etc.). To separate the unreacted part from the product chemist will use small distillation column with just one stage, but Chemical Engineer’s job is to design that Distillation Column with multiple stages. Here Mass Transfer (Flow of mass from one phase to another.) comes into picture. Fluid Mechanics is already involved since we deal with fluids, in the reactor. Also Thermodynamics too is crucial as that’s the one which tells that the particular process is possible or not. Material and Energy Balance are already involved as there is a reactor. Thus, the chemist just verifies that the process is feasible and the rest is done by Chemical Engineer.

Penicillin was thoroughly used during World War 2 to treat injured soldiers and hence lot of lives were saved. Chemical Engineer had a crucial role here in producing Penicillin on such a large scale. Also the revolutionary Haber’s Process flourished Fertilizer Industries at the point of time when there was shortage of food due to increasing population.

"Penicillin started as a chance observation. My only merit is that I didn't neglect the observation".                                                      - Alexander Flaming

Now, Chemical Engineering is just about making sure that the product is produced on large scale with maximum profit. That is, we engineer look just on macroscopic level. However, what actually happens in reactor on microscopic level is studied by chemist and that study on how reaction actually occurs is called Science.

After understanding about chemical engineering in simple words, let's have a look at a formal definition given by AICHE {American Institute of Chemical Engineers}: Chemical Engineering is the application of principles of physical sciences, together with principles of economics and human relations to fields that pertain directly to processes and process equipment in which matter is treated to affect a change in state, energy content or composition. Also there is one latest definition given by Martin Denn in one his books: Chemical Engineering is the field of applied science that employs physical, chemical and biochemical rate processes for the betterment of humanity.

There is one jocular definition of a chemical engineer which is given as, Chemical Engineer is the one who talks engineering in presence of chemists, chemistry in presence of engineers and politics in the presence of both.  

About Chemical Industry:

The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into more than 70,000 different products. Although chemicals were made and used throughout history, the birth of the heavy chemical industry (production of chemicals in large quantities for a variety of uses) coincided with the beginnings of the Industrial Revolution in general. One of the first chemicals to be produced in large amounts through industrial processes was sulfuric acid. In 1736, the pharmacist Joshua Ward developed a process for its production that involved heating saltpeter, allowing the sulfur to oxidize and combine with water. It was the first practical production of sulphuric acid on a large scale. John Roebuck and Samuel Garbett were the first to establish a large-scale factory in Prestonpans, Scotland, in 1749, which used leaden condensing chambers for the manufacture of sulfuric acid.

Polymers and plastics, especially polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polystyrene and polycarbonate comprise about 80% of the industry’s output worldwide. These materials are often converted to fluoropolymer tubing products and used by the industry to transport highly corrosive materials. Chemicals are used in a lot of different consumer goods, but they are also used in a lot of different other sectors; including agriculture manufacturing, construction, and service industries. Major industrial customers include rubber and plastic products, textiles, apparel, petroleum refining, pulp and paper, and primary metals. Chemicals are nearly a $3 trillion global enterprise, and the EU and U.S. chemical companies are the world's largest producers.

                           This video gives a glimpse of different chemical industries.