Industrial Pollution In Ghana: Some Selected Case Studies Of Industries In Tema

Abstract Waste waters from eight selected industries namely Tema Oil Refinery, Tuyee Manufacturing Industries, Cocoa Processing Company, Tema Lube Oil Company Limited, Pioneer Food Cannery Limited, Bridaltrust Paints Company Limited, Ghana Textiles Manufacturing Company and Ghana Textiles Printing Company Limited were sampled and subjected to various physico-chemical and trace metal analysis to determine levels of pollutants, using standard methods of WHO, AO AC and APHA. Generally, the ROD values were found to be high for all the industries. Some other parameter levels were significantly high enough for the individual industries to deserve attention. Generally, the results seem to suggest that these industries sited in Tema, are likely contributors to the high degree of" pollution of the Chemu n and Gao Lagoons which have been reported by various workers as being highly polluted. Consequent to the results obtained, an attempt was made to treat the wastewaters. Thus wastewaters of three of these major industries Ghana Textiles Manufacturing Company. Pioneer Food Cannery Company Limited and Tema Lube Oil Company Limited, representing the textile, food and petroleum-based industries in the Tema industrial area of Ghana were subjected to various physical and chemical treatments using mainly local materials, to try and reduce the levels of pollutants detected in the earlier investigations. Sedimentation, filtration using paper and sea-sand and adsorption using charcoals prepared from dried coconut husks and palm kernel husks as well as industrially prepared activated charcoal as adsorbents, were some of the physical methods used whilst chemical precipitation and oxidation-reduction were the chemical methods used to bring about the desired results. Six different naturally occurring soil samples from Ankaful, Ekon and Elmina in the Central Region, Asokwa in the Ashanti Region, Bokazo in theWestern Region and Somanya in the Eastern Region were also used to obtain some levels of purification and the results compared. Most of the methods decreased the levels of pollutants determined in the earlier investigations. Biochemical Oxygen Demand, nitrate, phosphate, conductivity, turbidity and colour of the waste waters were brought significantly to the acceptable limits of World Health Organization and Environmental Protection Agency and trace metals were reduced, in some cases to below detectable limits making the waters safe for re-use domestically and industrially. Sand filtration stood out as die single best method for the treatment of the wastewaters. The easy availability and affordability of sand coupled with the simplicity of its use in filtration should make it a convenient method for the treatment of impure water on a small scale in industry as well as in homes and farmsteads