A influência da recirculação de lixiviado na produção e qualidade do biogás gerado em aterros sanitários: revisão sistemática

Abstract

Over the last few decades, many technologies have been developed in order to minimize or even avoid pollution caused by biogas and leachate generated in landfills. Leachate recirculation (RL) is an example of this. The main objectives of this technique are to reduce the costs associated with the transport and treatment of leachate, promote a faster stabilization of the organic fraction of municipal solid waste and increase the production of biogas aiming at energy use. Therefore, this study aimed to evaluate the influence of RL on the quality and/or production of biogas generated in landfills. For this purpose a systematic review of the literature on this subject was conducted, contributing to the construction of an updated synthesis on the main results achieved in research carried out on a laboratory scale and on a large scale. The results found showed that the accumulation of toxic compounds is one of the main problems observed with the practice of RL. The use of additives, the control of the rate and frequency of recirculation and the supplementation of heat to the recirculated leachate were some of the techniques observed that have been investigated as a means of improving the influence of recirculation in the process of biodegradation of waste and increase the production of biogas. The results found showed that RL impacted in different ways the production and quality of the biogas generated through the decomposition of waste, proving to be effective in some studies to increase the production and quality of biogas, as well as technique ineffective for this purpose in other studies.