State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
J Hazard Mater. 2017 Jun 5;331:117-122. doi: 10.1016/j.jhazmat.2017.02.040. Epub 2017 Feb 23.
The effects of sludge characteristics, pyrolysis temperature, heating rate and catalysts on the release of HS and mechanism of HS formation during sludge pyrolysis were investigated in a microwave heating reactor (MHR). The evolution of sulfur-containing compounds in the pyrolysis chars obtained at temperature range of 400-800°C was characterized by XPS. For a given temperature, the maximum concentration of HS appeared at moisture content of 80%. Compared to the influence of heating rate on the HS yields, pyrolysis temperature and catalyst played a more significant role on the release of HS during microwave pyrolysis process. The HS concentration increased with increasing temperature from 400°C to 800°C while decreased with increasing heating rate. Both the Nickel-based catalyst and Dolomite displayed significant desulfurization effect and Ni-based catalyst exhibited the larger desulfurization capability than that of Dolomite. The organic sulfur compounds accounted for about 60% of the total sulfur in the sludge which was the main reason for the formation of HS. The mechanism analysis indicated that the cleavage reactions of mercaptan and aromatic-S compounds at temperatures below 600°C and the cracking reaction of sulfate above 700°C respectively were responsible for the HS release during sludge pyrolysis.
在微波加热反应器 (MHR) 中研究了污泥特性、热解温度、加热速率和催化剂对 HS 释放的影响以及污泥热解过程中 HS 形成的机制。通过 XPS 对在 400-800°C 温度范围内获得的热解焦中含硫化合物的演变进行了表征。对于给定的温度，HS 的最大浓度出现在 80%的水分含量下。与加热速率对 HS 产率的影响相比，热解温度和催化剂在微波热解过程中对 HS 的释放起着更重要的作用。HS 浓度随着温度从 400°C 升高到 800°C 而增加，而随着加热速率的增加而降低。镍基催化剂和白云石都表现出显著的脱硫效果，而镍基催化剂的脱硫能力大于白云石。有机硫化合物约占污泥中总硫的 60%，是 HS 形成的主要原因。机理分析表明，低于 600°C 时硫醇和芳族-S 化合物的断裂反应以及 700°C 以上时硫酸盐的裂解反应分别是污泥热解过程中 HS 释放的原因。
