Abstract:
Effluents samples from major abattoirs located in Akure, an urban city in Southern Nigeria, were investigated for possible presence of pollutants and their effects on the ' immediate environment.
Seven abattoirs within the city of Akure were identified, out of which four most prominent ones were studied. Samples of effluents and water were collected at different location from the vicinity of the abattoir sites following standard procedures. The period of sampling extended lrom May to .July 2004, which falls within the raining period in the city of Akure. during which appreciable flow occurred in the waste effluent receiving streams. the samples were analysed to determine the physicochemical and microbiological parameters. The results of effluents were compared with the World Health Organisation (WHO) standards and the pollution determinants were determined.
Findings indicated that the Total Suspended Solid (TSS) varied between 350 and 540 mg/l, which were quite high compared to WHO (1996) standard of 100 mg./I and the Conductivity varied between' 8,6 x 10^2 and 24.0 x 10^2 x 10^2 which indicated the samples were heavily loaded colloidal, organic, inorganic and suspended matters. The values of the Total Solid from all the abattoirs were too high. It ranged from 298 to 690, compared to the WHO (1996) standard of 1200mg/l since the solids wastes were separated from the effluents either manually , or with screens particularly in one of the abattoir. The microbiological analysis showed that the average total bacteria count from the various samples ranges between 3.0 x 10^6 and 7.6 x 10^6 , which were quite high. The presence of Ecoli and Staphylococcus areas were confirmed, which are indicators to confirm the presence of micro organisms associated with water-borne diseases.
A low cost treatment plant containing a screen, a septic tank and a filtration tank was designed and evaluated and the effluent characteristics were compared before and after treatment. This project offers some suggestions on methods for pollution free slaughterhouse operation in a developing country.
