Survey on Quantity and Quality of leachate from different steps of municipal Solid Waste Composting in Windrow method

One of the main problems in composting in Iran is a production of leachate in high volume. The main aim of this study was to evaluate the quality and quantity of municipal solid waste composting leachate from different stages of Isfahan composting plant.

This descriptive study was performed to determine the chemical quality of leachate samples from different stages of the composting process, in the 4 season and was done monthly as grab sampling. Leachate flow measurements were carried out at the site. Chemical parameters including pH, COD, TSS, EC, ammonia, phosphorus and heavy metals (Cd, Zn, Pb, and Cr) from 4 ports (Receiving hall, Shredding, Press and fermentation site) was analyzed.

The composting plant average flow was 0.4L/s that the maximum and the minimum flow were measured 1.2 and 0.2 L/s respectively. Effluent flow of receiving hall, Shredding, Press and fermentation site was measured 0.04, 0.08, 0.08 and 0.3 L/s respectively. The average COD concentration of leachate from receiving hall, Shredding, Press and fermentation site was 39864, 104643, 29898, 119592 and 99660 mg/l respectively.

The maximum flow and organic pollution load of leachate originates from fermentation site. The minimum of mentioned parameters and the maximum of heavy metals were measured in the Shredding part. Source separation and waste recycling is the most important way to reduce the production of leachate.