Municipal Sewage Sludge Used as Reclaiming Material for Abandoned Mine Land

The disposal of sewage sludge and land restoration in abandoned mine area have become the two major problems in the process of urbanization,which have caused great attention by government. A new type of reclaiming medium which was mixed by coal fly ash and sewage sludge was studied. The results indicated that when the proportion of coal fly ash reached to 6 g/100mL and 8 g/100mL, the dewater ability of sludge increased significantly. Then, after pressed under 0.5 Mpa for 10 min, the moisture content of the sludges droped to 40%-45%. By these means, the slip resistance and compressive resistance of dehydrated sludge reached to 32-37 Kpa and 212-248 Kpa, which meet the requirements of reclaiming medium for abandoned mine land. This study afford a new theory and measure for reclamation. The more important is, because this process is based on waste control by waste, the reclaiming expense could be cut down, and the continuous and healthy development of the economy, society and environment could be promoted greatly.