Synergistic effects of bacterial consortium and thermal energy on treatment of sewage by waste stabilisation pond

Abstract

The low rates of biodegradation of organic pollutants in wastewater have been attributed to the daily fluctuation of temperatures, which affects microbial metabolism and activities in reactors. This work aimed to develop a method to degrade sewage pollutants using a synergistic effect of bacterial consortium and thermal energy, while a grey concrete pond served as the control. The results demonstrated that the temperature profile of ICCP showed that all through the experiment, the temperature was above 25 °C, which is a suitable temperature for mesophilic bacterial growth. A properly-stabilised effluent was achieved by the ICCP with a low biodegradation index between 0.11 and 0.14. The values of BOD (95%) and COD (74%) removal efficiencies were obtained at a 10-day retention time in ICCP, which is in accordance with standard of the United State Environmental protection Agency. Moreover, a comparison between a control and ICCP revealed that the latter emits heat energy 30% higher than the first. The temperature of 30 °C (dark) and 30.8 °C (light) produced a BOD removal > 90%. Therefore, this method could be considered to bridge the gap in daily fluctuation of temperature for enhanced biodegradation.•Designing of a thermal coated concrete pond to investigate their thermal performance during the dark and light condition•Bioremediation test for selection of mixed bacteria strain of high degradation potential used as inoculum•A detention time of 10 days under natural sunlight used for investigation for concentration balance of organic pollutant