Quality Assessment of Effluent from A Typical Food Processing Industry in Port Harcourt

Abstract

The study investigated the quality of effluent discharge from a food industry in a Port Harcourt suburb in Rivers State, Nigeria. The food industry is engaged in noodle pasta and vegetable oil production. The discharged effluent is channeled to a neighboring marshland about 220m away from the factory. The purpose of this study is to analyze the critical parameters of the food industry effluent in order to determine its pollution potential, and also assess its possible effect on the ecosystem. Standard test methods such as the APHA (American Public Health Association) and ASTM (American Society for Testing and Materials) methods were used to conduct the tests. Parameters examined were pH, conductivity, BOD, COD, SO42-, Cl-, PO43-, Oil and grease, NO32-, Turbidity, Fe, Zn, Pb, Cu, Cr, Cd, Ni. The data obtained from these analyses were used in assessing compliance with regulatory limits and identifying specific pollutants requiring targeted remediation. High values of oil and grease content were recorded both in the effluent (700.5±53.2mg/l) and in the recipient soil (3107±137mg/l) which were extremely above the WHO/NESREA acceptable limit of 10mg/l. The high values of the oil and grease were attributed to the absence of oil-water separator in the effluent treatment process. The mean values of BOD (34.42±9.7mg/l) and COD (153.4±42.4mg/l) were slightly higher than the WHO/NESREA acceptable limit of 30 and 150mg/l respectively. The control was however within the acceptable limit with recorded values as 28.0±5.4mg/l and 110±24.6 mg/l respectively. This indicates the presence of high organic load and a proof that the recipient environment is impacted. All the heavy metals tested in the effluent except Fe (0.77±0.25mg/l) were below the WHO/NESREA acceptable limit of ≤0.3mg/l. The discharged effluents were generally acidic which was indicated by low pH values with a mean of 5.09±0.6. Turbidity mean values was 40.3±8.5 NTU and these were above the regulatory limit of 5-10NTU. The general physical state of the effluent was turbid with whitish suspension or translucent with oily suspension on the surface. This indicated a poor treatment of the effluent. Effluent monitoring and treatment are necessary if the environment will be spared of the dangers. This paper, therefore, recommends that the food processing industry should effectively treat its effluents before disposal.