The Chemical engineering reference article from the English Wikipedia on 24-Jul-2004
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Chemical engineering

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Chemical engineering is the application of science, mathematics and economics to the process of converting raw materials or chemicals into more useful or valuable forms.

Chemical Engineering involves the design and maintenance of chemical processes for large scale manufacture. The actual name is a misnomer as the work of a chemical engineer involves more physics related knowledge than chemistry. Because the title 'chemical engineer' creates this misunderstanding, many chemical engineers are employed under the title of 'process engineer'.

The difference between chemical engineering and chemistry can be illustrated by considering the example of producing orange juice. A chemist working the laboratory investigates and discovers a multitude of pathways to extract the juice of an orange. The simplest mechanism found is to cut the orange in half and squeeze the orange using a manual juicer. A more complicated approach found is to peel and then crush the orange and collect the juice. A company then commissions a chemical engineer to design a plant to manufacture several thousand tonnes of orange juice per year. The chemical engineer investigates all the available methods for making orange juice and evaluates them according to their economical viability. So even though the manual juicing method is simple, it is not economical to employ thousands of people to manually juice oranges. Thus another, cheaper method is used (possibly the 'peel and crush' technique). What is the easiest method of manufacture on a laboratory bench will not necessarily be the most economical method for a manufacturing plant.

The individual processes used by chemical engineers (eg. distillation or chlorination) are called unit operations and consist of chemical reaction, mass-, heat- and momentum- transfer operations. Unit operations are grouped together in various configurations for the purpose of chemical synthesis and/or chemical separation.

Two main physical laws underlying chemical engineering design are Conservation of mass and Conservation of energy. The movement of mass and energy around a chemical process are evaluated using mass and energy balances which apply these laws to whole plants, unit operations or discrete parts of equipment. In doing so, Chemical Engineers use principles of thermodynamics, reaction kinetics and transport phenomena. The task of performing these balances are now aided by process simulators, which are complex software models that can solve mass and energy balances, and usually have built-in model to simulate a variety of common unit operations.

Table of contents
1 Related fields and topics
2 See also
3 External links

Related fields and topics

Today chemical engineering field is a diverse field covering areas from biotechnology and nanotechnology to mineral processing.

See also

External links