The Impact of Cassava Wastewater from Starch Processing Industry on Surrounding Soil: A Case Study of Matna Foods Industry, Ogbese

Abstract

This study is aimed at determining the impacts of indiscriminate disposal of processed cassava wastewater into the environment by determining the physicochemical characteristics of the wastewater and soil characteristics within the vicinity of starch processing industry.The cassava wastewaterquality wastested in accordance with the standard methods for the examination of water and wastewater while soil samples was analysed using Atomic Absorption Spectrometer. The result of cassava wastewatershows that the effluent is acidic with pH of 3.8 and high conductivity of 6500µΩ. The cyanide content is also very high with 0.17mg/l as compared to 0.05mg/l recommended by WHO. The total solid, total dissolved solid and total suspended solid are also in high range of 20619, 17048 and 3571 mg/l respectively. Its hardness is 812mg/l, chloride 2516mg/l and nitrate 470mg/l. The dissolved oxygen was not detected while COD and BOD were also on the high side with values of 560 and 1410mg/l respectively. The results of soil analysis indicates that the cyanide concentration is high at the surface but reduces with depth. The pH is also in acidic range. However, Magnesium, Sodium, Sulphate, Zinc, Chromium, Vanadium, Europium and Rubidium were not detected in the soil samples. The percentage of calcium, potassium, copper, manganese and titanium were small and varying between 0.07 and 6.37ppm. Three unlined aerobic ponds provided for the treatment of cassava wastewater reduces the pollution strength of the wastewater but the untreated wastewater interfere with the surrounding soil during conveyance to the pond as well as pond environment.It is recommended that the wastewater conveyance and ponds should be well designed to prevent interference with the surrounding soil.