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Sewage sludge taken from Guilin Wastewater Treatment Plant (WWTP) and elemental sufur(S0) were used as the bioleaching medium and substrate respectively. Acidification effect of sewage sludge, activity of bioleaching microorganism and removal rate of heavy metals were investigated at various temperatures from 10℃ to 40℃ in the bioleaching process. Where Bioleaching experiments were process was operated at 3g•L-1 S0 and 1.0L•min-1 aeration rate. An indigenous Acidithiobacillus thiooxidans was the bioleaching dominant bacteria in the process. The results showed that acidification rate and bacterial activity increased with temperature rising in the temperature range of 10℃~30℃. The optimum temperature range for bioleaching bacteria growth was 20℃~30℃. The activity of bioleaching microorganism was the highest at 28.9℃ and sulfate ions yield was 461.66(mg•L-1)•d-1, To achieve the treatment requirements and low operation energy consumption, the proper temperature for bioleaching engineering application should be controlled at 20℃. Under this condition, the removal rates of Cu, Zn and Cd were 47.45％、77.07 and 80.57％respectively after 5-day bioleaching. The residual concentrations of Cu, Zn and Cd in the treated sludge met with the national standard for sludge agriculture use in China.

Pot experiments were conducted to study the effects of 8 fertilizers (NH4Cl, NH4NO3, Ca(NO3)2, CO(NH2)2, Ca(H2PO4)2, KH2PO4, K2SO4 and KCl) on Ni uptake and distribution by rice. The results indicated that nitrogen and potassium fertilizers had little effect on the biomass and yield of rice, while the phosphate fertilizers significantly increased the biomass and yield of rice. The total amounts of Ni in rice were decreased by 12.3% - 38.8% after fertilizers were applied. Applying NH4Cl, Ca(H2PO4)2, K2SO4 and KCl significantly increased the concentration of Ni in the aerial parts of rice, whereas the rest 4 fertilizers decreased the concentrations of Ni in the aerial parts of rice. The concentration of Ni in the grain under maturity stage were 6.958 - 13.227 mg kg-1 after fertilizer were applied, which increased by 41.03% - 168.11%, and had significantly exceeded the national food heavy metal limits hygienic standard (0.4 mg kg-1). This study suggests that fertilizer application significantly increased the uptake of Ni of grain, and the effects of 8 fertilizers in the order: K2SO4＞KCl＞Ca(NO3)2＞NH4Cl＞CO(NH2)2＞KH2PO4＞NH4NO3＞Ca(H2PO4)2.

This paper presented a marginal method allocating transmission losses to bilateral exchanges in the context of bilateral trading, based on the special relation between marginal loss comparative values for different slack buses. The advantage of this method is that the sharing results are irrelevant to the selection of slack bus, which is able to intuitively reflect the transmission distance of bilateral exchange. Through Equivalent Bilateral Exchanges (abr. EBE) principle it is extended the application to loss allocation in the power pool. Finally, it is used in a Chinese provincial power grid to solve the issue of transmission loss allocation to bilateral exchanges. Results illustrate the feasibility and effectiveness of the method.