Papers by Author: Li Hong Wei

Abstract: The effects of sewage sludge on combustion of loading alkali metal pulverized coal is carried out by thermogravimetric analysis (TGA). The result shows sewage sludge decreases initial release temperature and ignition temperature of volatile matter(VM) during the combustion of loading alkali metal pulverized coal. The combustion of fixed carbon in coal was promoted by the metal material in sludge when the sludge mixing ratio(SMA) was lower than 20% or inhibited because of the cover of sludge ash when SMA was higher than 40%. Comparison of stacking curves of sludge and measured curves of loading alkali metal coal, finds that: (1) there is no effect between sludge and coal, for the volatilization of water and small molecule substance, the combustion characteristic curves are superimposed in both experimental curves; (2) the co-combustion is interactional and interrestricted continuous change process, can't direct obtain from superimposition of curves, for the combustion of VM and fixed carbon. While SMA is lower than 20%, the samples have good combustion characteristic than pure coal.

Abstract: The three-step of MSWI fly ash washing process, to remove chloride from fly ash as much as possible, were investigated. The results show that with the increase of L/S, the release of chloride and sulphate both increased at the first step, but the effect of second and third washing step decreased for chloride, while the effect for sulphate increased. The suitable washing condition happened with a L/S ratio of 5 and 2 minutes of washing, considering the two economic factors (water consumption and economical factor).

Abstract: The incorporation of cadmium into clinker during the co-processing of waste with cement kiln was investigated. Cadmium contained reagent was added to the cement raw meal to produce clinkers after clinkerization process. XRD analysis and SEM-EDS analysis were employed to indentify the major mineral phase of clinker and the cadmium contained mineral phase. Leaching test, sequential extraction procedures were employed to evaluate the leaching potential of cadmium in clinker. The results show the stabilization rate of cadmium during the clinkerization process is low. The incorporation ratio of cadmium in C2S is 0.32%~1.14%, the incorporation ability of cadmium in C2S is higher than C3S. The major mineral phases of clinker with the incorporation of cadmium were CH, C3S and C2S. The average leaching concentration of cadmium of clinker was 1.4 μg/L, which was higher than the blank samples. BCR Sequential extraction procedures analysis of the clinkers show exchangeable, water and acid-soluble fraction and residual fraction were very small, while the reducible phase of cadmium was up to 95.13%.