Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.
Institute of Civil Engineering, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, Warsaw, 02-776, Poland.
J Environ Manage. 2022 May 1;309:114683. doi: 10.1016/j.jenvman.2022.114683. Epub 2022 Feb 15.
Leachate is a contaminated liquid generated during the bio-chemical decomposition processes of municipal solid waste (MSW) that occurred at semi-solid or solid-state in a bioreactor landfill (BLF). Conceptually, leachate from a BLF is analogous to the urine generated in the 'human body', on which the medical practitioners rely to diagnose and remediate ailments. In line with this practice, to monitor the complex MSW decomposition processes, prolonged investigations were performed to establish the temporal variation of different chemical parameters (such as pH, electrical conductivity, chemical oxygen demand, organic- and inorganic carbon, nitrate- and ammonium-nitrogen, sugars and volatile fatty acids) of the leachate collected from different cells (age≈ 6-48 months) of a fully functional BLF in Mumbai, India. Furthermore, to understand the effect of the climate, MSW composition and landfill operating conditions on the rate of the decomposition process, chemical parameters of the leachate obtained from a landfill located in the central part of Poland were compared with the BLF. The study reveals that the chemical parameters, except for the pH, evince a rapid reduction with time and attain a constant value, which indicates the 'stabilized MSW'. Also, native microorganisms that are an integral part of MSW consume volatile fatty acids within a year in the BLF, which facilitate the rapid transformation of the decomposition process from acidogenesis and acetogenesis to the methanogenesis phase. It is worth iterating here that based on the long-term field study, a convenient and efficient methodology, which is currently missing from the literature, has been established to understand the kinetics of different phases of anaerobic decomposition. This study would be very helpful to the landfill operators, who are interested in accelerating MSW decomposition by augmenting leachate properties.
沥滤液是在生物反应器填埋场 (BLF) 中半固态或固态下发生的城市固体废物 (MSW) 的生物化学分解过程中产生的受污染液体。从概念上讲，BLF 的沥滤液类似于“人体”中产生的尿液，医生依靠它来诊断和治疗疾病。为了监测复杂的 MSW 分解过程，按照这一做法，进行了长期的调查，以确定从印度孟买一个功能齐全的 BLF 的不同单元 (年龄约为 6-48 个月) 收集的沥滤液的不同化学参数（如 pH 值、电导率、化学需氧量、有机和无机碳、硝酸盐和铵氮、糖和挥发性脂肪酸）的时间变化。此外，为了了解气候、MSW 组成和填埋场运行条件对分解过程速率的影响，将从波兰中部一个填埋场获得的沥滤液的化学参数与 BLF 进行了比较。研究表明，除 pH 值外，化学参数随时间迅速减少并达到恒定值，这表明 MSW 已“稳定”。此外，作为 MSW 不可分割的一部分的本地微生物在 BLF 中一年内消耗了挥发性脂肪酸，这促进了从产酸和产乙酸到产甲烷阶段的分解过程的快速转化。值得在这里重复的是，基于长期的实地研究，建立了一种方便有效的方法，目前文献中还没有这种方法，用于了解厌氧分解的不同阶段的动力学。这项研究将对那些有兴趣通过增强沥滤液特性来加速 MSW 分解的填埋场运营商非常有帮助。
