Study on the Wastewater Characteristics of the Kitchen Effluent

Abstract

The implementation of low-cost, simple mitigation measures are required for the timely control and sustainable management of pollution problems in developing countries. This study was designed to investigate the wastewater characteristics of the kitchen effluent, and to design a low-cost wastewater treatment plant for the kitchen based on the data obtained. For the wastewater quality analysis of the kitchen effluent, various composite samples were collected from the local region. The samples were collected at regular interval for a period of 4–6 weeks and were tested for various wastewater quality parameters. The wastewater generated by the kitchen is highly polluted in terms of releasing a high-strength effluent. The mean average values COD, BOD, TSS and TDS observed was 2185, 1755, 853 and 1300 mg/L, respectively. The effluent is highly alkaline, with a pH of more than 8.20 and has objectionable odor and smell. Moreover, it has very high temperature, i.e., 18 °C, at the point of its disposal into the receiving streams. The effluent of the kitchen is also found to have very critical DO concentration, i.e., 3.01 mg/L. That can adversely affect entire water ecosystem, having such high organic pollutant strength. The proposed wastewater treatment plant for the kitchen comprises medium screens, PST and the UASB reactor. The required dimension of the PST operating at SOR of 3.05 ft³/ft²-h was calculated to be L × W × H: 40 ft × 25 ft × 12 ft. And that of the UASB reactor is 38 ft diameter and 12 ft height will be able to remove more than 80% of the COD and BOD from the effluent of the kitchen. Additionally, it will generate a biogas for the domestic requirements of 1780 persons, by an estimated biogas yield 1040 m³/day