Chemical refining

The sheU-and-tube exchanger is the workhorse of power, chemical, refining, and other industries (Fig. 8). One fluid flows on the inside of the tubes whereas the other fluid is flowing through the sheU and over the outside of the tubes. Baffles are used to ensure that the sheUside fluid flows across the tubes, thus inducing high heat transfer. 

E. Meyer, Petroleum Sulfonates—ChemicalMmphihians, Sonnebom Chemical Refining Corp., New York, 1960. 

International Society for Measurement and Control (ISA). The chemicals, refining, and foods industries generally follow this standard. 

Biotechnology can potentially provide solutions to some of these problems. Bioprocesses are, in general, environmentally better than chemical refining processes. 

De Klerk, A., Dancuart, L. P., and Leckel, D. O. 2005. Chemicals refining from Fischer-Tropsch synthesis. Paper presented at the 18th World Petroleum Congress, Johannesburg, cdl85. 

Introduction Front-end loading (FEL) is the process by which a company develops a detailed definition of the scope of a capital project that meets corporate bnsiness objectives. The term frontendloading was first coined by the DnPont company in 1987 and has been used throughout the chemical, refining, and oil and gas industries ever since (Porter, James B., E. I. DuPont de Nemours and... 

The businesses of chemicals, coatings and plastics are closely linked, and those sectors, in turn, are closely linked to the oil and gas industry. Plastics comprise a branch of petrochemicals—that is, chemicals refined from petroleum. Total world consumption of oil for industrial uses is about 30 million barrels daily—mostly for use in chemical processes. Coatings, which include paints, are chemical concoctions. Other everyday chemicals products include pharmaceuticals, fertilizers, dyes, fibers, packaging, adhesives and explosives, among... 

Standard Method for Chromatographic Analysis of Chemically Refined Cellulose, ASTM D 1915-63, American Society for Testing Materials Philadelphia, PA, 1979. 

In 2001 it was estimated that the world merchant market for catalysts was worth ca. US 25 billion, divided roughly equally between refining, petrochemicals, polymers, environmental (20-25% each) and with about 11% being used in fine chemicals. Refining is about the production of fuels (Chapter 3, Box 2), petrochemicals cover many of the basic commodity chemicals and the monomers required for the polymer industries fine chemicals include pharmaceuticals and agrochemicals, as well as flavours and fragrances and environmental is about exhaust gas and waste product clean-up. Vehicle catalytic converters use catalysts, as does the production of the main tonnage polymers polyethylene, polypropylene, polystyrene, polyvinyl chloride and polyethylene terephthalate. 

Figure 4.4 shows the different stages in seed preparation and a classical chemical refining process. The general methods employed to produce edible oils suitable for human consumption consist of (a) seed preparation, (b) extraction, (c) degumming, (d) neutralization, (e) bleaching, (f) deodorization, (g) hydrogenation, and sometimes winterization. 

Refining of crude fats and oils involves a series of steps for the removal of impurities from the glycerides to make the product suitable for human consumption and improve product shelf life. The impurities are fatty acids, phosphatides, metal ions, color bodies, oxidation products, solid paricles, and volatiles that include objectionable odors. Crude coconut oil is refined by any of the following methods (1) chemical refining (batch or continuous) and (2) physical refining. The comparative performance of both methods is summarized in Figure 4. 

Deodorization is the last step in chemical refining. Volatile odoriferous substances, including low-molecular-weight fatty acids, are removed by stripping with steam under reduced pressure. The final product is generically called RBD (refined, bleached, and deodorized) coconut oil. 

A lower grade product called Cochin oil is coconut oil that is chemically refined and bleached but not deodorized. 

Figure 12. Flow diagrams of A) physical refining and (B) chemical refining of crude palm oil.

Chemical Refining. Also called caustic refining, chemical refining involves three stages (1) gum conditioning and neutralization, (2) bleaching and filtration, and (3) deodorization. 

Values of RF for chemical refining range from 1.5 to 2.0, while lower figures of 1.2-1.4 are usually recorded in physical refining. 

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