Science of Industrial Processes
Preface
The bulk of the original work summarised in this section of the website is concerned with the ‘Science of Process Manufacture’ which I have helped to establish as a field of study, research and application over a period of 45 years. Reference is also made to the work of my colleagues and students in ICI and UMIST where as part of their responsibilities it has direct bearing on the various subjects described [See people and places].
Besides the work on manufacturing chemicals, polymers, composites and things made from these – extrusions, mouldings, films, fibres and foam – there are three closely related areas where the science and engineering tools and concepts devised for manufacture have been applied to fields outside manufacturing, though closely related to it:
- Internal combustion engines
- Jet-stirring of reservoirs and harbours
- Design of energy conversion systems
The combustion engine work is focussed on the (cracking and oxidation) processes which commonly give rise to carbon (soot) particulates in its exhaust.
The jet-stirring (qv) technology devised for chemical reactors has been applied to reservoirs for the suppression of algae and to harbours to disperse the sudden efflux of high concentrations of noxious effluent from nearby factories.
Both the combustion and jet applications are archived here under the “Industrial Scale” heading (opposite).
Energy conversion involves mainly nuclear fission and steam technologies, combustion of hydrocarbons and steam technologies, and wind turbines. The work here is mainly at the level of the system of supply of electricity and the economics of different conversion technologies. This work is archived under “Energy Economics” on the “Industry and Economics” section of this website.
Manufacture itself may be divided into two broad categories:
(A) Process Manufacture (PM) and
(B) Electro-Mechanical Manufacture (EM)
In the UK currently, PM accounts for about 60% of value added in manufacture, EM about 40%.
Process Manufacture is defined here as the conversion on the industrial scale of one set of materials into another set of different molecular and physical forms. This conversion is accomplished by flow processes in either continuous or repetitive batch sequences in the fluid or gaseous state. A long-term goal from the earliest 19th century processes has been to convert batch processes to continuous ones to reduce costs and human intervention. Such conversions depend absolutely on the scale and variety of manufacture required, which in turn is dictated by the market. Research on methods, whether mathematical or experimental, and on phenomena, is always aimed at optimisation on the industrial scale, whether by systematic improvement of what exists, or innovation to meet a need revealed by process or product.
Process Manufacture is the central feature of the steel, cement, oil refining, chemical and polymer industries. It also plays a prominent part in the food and pharmaceutical industries both in the manufacturing processes themselves and the chemical ingredients which are integral to the products. Polymeric (“plastics”) packaging, often blamed for damaging the environment, is of central importance to the food and pharmaceutical industries.
The work reported here in the papers and reports (grouped in the categories in the right-hand pane) is mainly concerned with chemical and polymer processes, but most of the concepts, mathematical model structures and experimental methods have been devised to be generalizable across all of Process Manufacture including food and biotechnology.
Electro-Mechanical Manufacture is the assembly of solid components to make another component or, at the end of a succession of steps, the final product which may be a machine or consumer product. Many of the components will be shaped in the solid state by mechanical means – cutting and bending, but many also by fluid processes such as soldering, casting and moulding. Mechanical and Process Manufacture come together in the manufacture of synthetic polymer fibres, principally polyester, polypropylene and nylon, where the precision and durability of the mechanical equipment required to control, in time and space, the drawing and texturing of literally thousands of filaments and threadlines is an astonishing feat. Drawn filaments for polyester and nylon hosiery for instance are just over 2 microns in diameter. Threadlines for textile uses may be assemblies of 30 or 40 filaments. These filaments are made at speeds of up to 10,000 metres per minute (500 feet per second) which is unmatched in any other mass production industry. The supra-molecular and crystalline structures generated by these processes in the filaments directly affect dye uptake. This is the most sensitive measure of consistency there is which is directly observable by the operator and the customer, for instance in piece-dyed fabrics, which are themselves drapeable assemblies of up to 6,000 continuously woven or knitted threads [see papers].