摘要
In this work we investigated the chemical, thermal and toxic properties of dried sewage sludge （DSS）, the preparation and properties of lightweight sludge ceramic （LSC） and the mechanisms of action of the organic and inorganic foaming agents （OFAs and IFAs）. The chemical components and thermal properties of the raw materials were studied by Energy Dispersive X-ray Detection （EDX） and Thermogravimetric Analysis and Differential Scanning Calorimetry （DSC/TGA）. The mineral phases of the raw materials and the formed ceramics were determined by X-ray Diffraction （XRD）. The leaching characteristics of heavy metals were investigated with inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）. Different ratios of DSS and clay were mixed and pressed into raw pellets. After drying and preheating treatment, the raw pellets were sintered at 1150℃ for 10 rain. The physical properties of LSC （50 wt% DSS added） were tested. The results showed that when the addition of DSS was above 50 wt%, LSC began to shrink, and a maximum density occurred. The environmental safety of LSC was satisfactory. XRD showed that some new mineral phases formed in the LSC. Observation of the microstructure by Scanning Electron Microscope （SEM） indicated that the body of LSC was porous.
In this work we investigated the chemical, thermal and toxic properties of dried sewage sludge （DSS）, the preparation and properties of lightweight sludge ceramic （LSC） and the mechanisms of action of the organic and inorganic foaming agents （OFAs and IFAs）. The chemical components and thermal properties of the raw materials were studied by Energy Dispersive X-ray Detection （EDX） and Thermogravimetric Analysis and Differential Scanning Calorimetry （DSC/TGA）. The mineral phases of the raw materials and the formed ceramics were determined by X-ray Diffraction （XRD）. The leaching characteristics of heavy metals were investigated with inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）. Different ratios of DSS and clay were mixed and pressed into raw pellets. After drying and preheating treatment, the raw pellets were sintered at 1150℃ for 10 rain. The physical properties of LSC （50 wt% DSS added） were tested. The results showed that when the addition of DSS was above 50 wt%, LSC began to shrink, and a maximum density occurred. The environmental safety of LSC was satisfactory. XRD showed that some new mineral phases formed in the LSC. Observation of the microstructure by Scanning Electron Microscope （SEM） indicated that the body of LSC was porous.
