Digested sewage sludge solidification by converter slag for landfill cover.
A new technology for solidification of digested sewage sludge referred to as converter slag solidification (CSS) has been developed using converter slag as the solidifying agent and quick lime as the solidifying aid. The CSS technology was investigated by analyzing the physicochemical properties of solidified sludge and determining its microstructural characteristics. The feasibility of using solidified sludge as a landfill cover material was considered in the context of the economical recycling of waste. Sludge solidified using the CSS technology exhibited geotechnical properties that are appropriate for replacing currently used cover soil. Microscopic analyses using XRD, SEM and EDS revealed that the main hydrated product of solidification was CSH (CaO . SiO2 . nH2O), which may play an important role in the effective setting process. Negligible leaching of heavy metals from the solidified sludge was observed. The solidification process of the hydrated sludge, slag and quicklime eliminated the coliform bacteria. Recycled sewage sludge solidified using CCS technology could be used as an effective landfill cover.
Kim
Eung-Ho
EH
School of Urban and Civil Engineering, Hongik University, Sangsudong 72-1, Mapogu, Seoul, Republic of Korea.
Cho
Jin-Kyu
JK
Yim
Soobin
S
D017610:Calcium Compounds / Q000737:chemistry; D007220:Industrial Waste; D007723:Korea; D008669:Metallurgy; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000032:analysis* / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission; D014961:X-Ray Diffraction
D017610:Calcium Compounds; D007220:Industrial Waste; D010087:Oxides; D012722:Sewage; C016538:lime