Refuse Degradation and Stabilizing Process in Municipal Refuse Test Lysimeters
Zhu Qingshan;Zhao Youcai;Xu Dimin(National Laboratory of Pollution Contyol and Reclamation, Tongji University, Shanghai, 200092)
Twenty-four test lysimeters containing 20-30kg prepared and residential refuse each were monitored for the settlement of refuse surface under a constant pressure of 0.05MPa and for leachate generation rate as well as the evaluation of stabilizing time of refuse landfill in Shanghai. Different chemicals such as KH2PO4, (NH4)2CO3, KCl, CuSO4, Na2MoO4, Na2WO4, FeCl3, K2Cr2O7, acetic acid and sludge, were added to the lysimeters respectively and the settlement rate of refuse surface and generation rate of leachate were determined. It was found that the addition of N, P and K was favorable to the degradation of refuse,increasing the settlement rate of refuse surface and accelerating stabilization of landfill, while the other chemicals have little effect on the degradation of refuse.Based on the relationship between settlement rate and time, the take for landfill stabiuzation was evaluated. The experimental results showed that about 2 years were required for a refuse of 50cm height which was used in the experiments. If N,P and K were added to the refuse, the stabilization take will be shortened considerably.