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The combustion characteristics of textile dyeing sludge，sawdust and its blends at different proportions were studied by thermogravimetric analysis(TG-DTG) at different heating rates. The results showed that there existed four obviously temperature zones during the textile dyeing sludge combustion curves, which were corresponding to moisture's exhalation、two stages of devolatilizations and fixed carbon combustion. With the increasing of heating rates, the burning time was shorten and the combustion rate was faster of the textile dying sludge. DTG curve of the blends was more closed to that of the larger proportions. Comprehensive combustion characteristic index SN of the sludge-sawdust blends showed an uptrend, which demonstrated that higher volatility had better combustion characteristics.

Sludge from tannery was solidified and stabilized by using lime, PFA and cinder as the solidifying agents，investigation of solidifying agents affect toxic heavy metals in tannery sludge and the optimum conditions of sludge solidification/stabilization were analyzed. The results showed that under the dosage of lime, PFA and cinder were 0.12kg/kg, 0.02kg/kg and 0.08kg/kg respectively, and curing time was 6 days, the compressive strength of the solidified sludge block reached 884KPa while the moisture content of the solidification block was 30.2%，which met with the standards of landfill. Compared with the untreated tannery sludge，the concentration of Cu、Pb、Zn、Ni and COD of the leaching from the sludge solidification block was reduced by 92.1%、96.7%、92.8%、88.9% and 75.9% respectively，the Cr、Cd、and Mn were undetectable.When lime and PFA ratio was 6:1, the solidified block have good synergistic solidification effects.

In this thesis, polystyrene nanomembranes made by electrospinning technique were utilized to deal with Cu2+(5mg/l), Cr6+(5mg/l) and methylene blue (10mg/l) contained in simulated dyeing wastewater. Polystyrene liquor (8% (m/m), dissolved in chloroform) was electrospun and processed nanofibrous membrane; the nanofiber diameter was 250nm~15µm; the detected pore size was 3nm~0.5µm and the membrane thickness was 170µm. A plate membrane system was used to test nanofiltration characteristics of pollutants (Cu2+, Cr6+ and methylene blue). The experiment showed that the interception rates were above 91%, and the water flux was about 5.8-15.4ml/ (cm2h).

Sewage sludge incineration residue was obtained from a sewage treatment plant in Guangzhou and used as a low-cost sorbent for removing Ni2+ from wastewaters. The adsorption effectiveness and their factors of Ni2+ in aqueous solutions were simulated detailed using the adsorbents of the sludge incineration residue. The simulation contents and the factors included the adsorption time, the pH of solution and the dosage of adsorbents and so on. The results showed that at room temperature, the adsorption equilibrium of Ni2+ can be achieved in 6h and the best pH value of the solution was about 7.0. The removal rates of Ni2+ were increased with the adsorbent concentration increasing and the optimal concentration of adsorbent was 10g/L with the initial concentration of Ni2+ less than 30mg/L.At the best adsorption conditions, the removal rate of Ni2+ reached more than 70%.

For better harmlessly treatment of papermaking sludge, a new technology for solidifying and stabling of sludge was studied. Papermaking sludge was solidified and stabilized by the solidifying agents including cement, powder fly ash (PFA) and cinder. The mechanical properties of solidified sludge block were evaluated by compressive strength, chemical oxygen demand (COD) and heavy metals concentration in the leachate from the solidified block were tested as well. When the solidifying agents has the following composition (cement 0.12kg/kg, PFA 0.02kg/kg and cinder 0.10kg/kg respectively), and the curing time was 6ds, the compressive strength of the solidified sludge blocks reached 360kPa. The results showed that cement and cinder were all positive in the compressed strength of sludge block. If they were mixed with PFA together, they could enhanced the solidification of organic and heavy metals in the sludge. Under this conditions, the COD in leachate from the solidified block was 115.7 mg/L, and the heavy metal concentration had reached the related national standards, after 6ds of curing time, water ratio of the solidified block kept from 35% to 40%, which met the prescribed standards of landfill.