Performance evaluation of a landfill leachate recirculation treatment system using quadric model

Abstract

Aim :Methodology : Results :Interpretation :The present research was carried out to study the effects of recirculation of leachate in cylindrical shaped anaerobic bioreactor on treatment of leachate as well as stabilization of municipal solid waste. Quadric and regression model were used to study the behavior of operating parameters over time scale and on COD, respectively.19 kg of solid waste was filled and compacted and in reactor and water was added to it till 20 liters of leachate prepared. The whole unit was sealed air tight and leachate was recirculated @ 28ml/min for 12 hours daily. Physico-chemical characterization of leachate and and solid waste was done by using standards methods of analysis.Results shows that the parameters like pH (6.69 to 7.74), alkalinity (7100 to 1600 mg l ), VFA alkalinity ratio (1.44 to 0.33) etc. were within the optimum range of anaerobic degradation. COD is an indicator of organic contamination and a reduction in 96% COD was observed at the end of 29 weeks of leachate recirculation. The quadric model also confirms that the most of organic and inorganic contaminants of leachate were decreased and alkalinity was increased with time. In addition to leachate treatment, a reduction of 26.3% volume of MSW was observed after completion of study.The performance of Leachate Recirculation Bioreactor was excellent as most of organic and inorganic contaminants were decreased and pH and alkalinity were increased with time. Thus, this technology can be a good solution of MSW problems of countries like India which demands urgent attention in this direction as it treats the leachate as well as stabilize the solid waste.

Evaluation of Leachate Recirculation as a Stabilisation Strategy for Landfills in Developing Countries

“…The greater COD and BOD5 increments in Br2 indicate the effect that LR has on initial waste degradation stages, as has been observed in similar studies with EW [45,46]. LR could have accelerated hydrolysis and acidogenesis processes in Br2 by favouring greater leaching of soluble organic substances from the solid waste to the liquid phase which, when recirculated, improves the contact between biomass and the more easily assimilable waste fractions [19]. This, together with the variable biodegradability characteristics of the various materials found in MWS, might explain the fluctuation in BOD/COD observed.…”

“…The limited applications of SSL in DC evidence the need to investigate its applicability by considering the type of waste disposed of and landfill operating conditions in these countries. Previous studies, conducted mainly with fresh waste (FW) from landfills of the organic fraction of MSW, have denoted the positive effect of LR on biogas production and parameters used as stabilisation indicators for landfills, such as volatile solids (VS), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) [19][20][21][22]. Additionally, several studies in DC have reported a positive effect of LR on landfill settlement [23,24].…”

“…In contrast to FW research, few studies in DC have evaluated LR with excavated waste (EW) from landfills [19,24]. Most of the landfill stabilisation criteria have been suggested based on studies conducted in developed countries, in terms of parameters such as BMP, respirometric index, total organic carbon (TOC), COD, BOD, BOD/COD ratio, cellulose, lignin, cellulose to lignin ratio (C/L) and ammoniacal nitrogen (NH 4 + ) [2,14,[25][26][27][28].…”

Rapid decomposition method of landfill leachate in recycling stations

“…Two times model and regression model were used to study the variation of operating parameters with time and influence on COD, and the physical and chemical characterization of leachate and solid waste was carried out by standard analysis method. Through experiments, it was proved that most of the organic and inorganic pollutants in the leachate decreased with time, and the alkalinity increased, which indicated the leachate cycle bioreactor has excellent performance, but this method is more complex and difficult to implement (Lohchab and Singh, 2017). Under anaerobic condition, the collected leachate was recycled in a cylindrical bioreactor using domestic solid waste as raw material, and various parameters of leachate collected from outlet were analyzed.…”