Laboratory Analysis and Prediction of Settlement of Municipal Solid Waste Under Anaerobic Condition

Abstract

The settlement of municipal solid waste under anaerobic condition is considered important for structural stability even after closure of the landfill. In this context, the settlement of waste was analyzed under constant loading in the anaerobic reactor. A settlement value of 29.9% was observed in the reactor immediately after load placement on the sample. Consolidation analysis of the collected municipal solid waste showed that the primary settlement of the waste completed after 48 h of load application. The total secondary settlement was observed to be 5.85% at the end of 202 days. From the results obtained for the biogas generation and settlement, the rate of degradation of waste was observed to be 0.477 day−1. The settlement of landfill depends upon composition, moisture content, depth, density and compression characteristics of waste. The municipal solid waste thus needs analysis of biodegradation rate and also a mathematical model to predict the settlement. Thus, the mathematical modeling of predicting the settlement of landfill showed that initially the rate of settlement of the waste was high due to high degradation rate of organic contents. The settlement of 6.4% due to biodegradation and 10–18% was predicted due to mechanical compression in the landfill.