【作者】 王丹；

【导师】 胡勤海；

【作者基本信息】 浙江大学 ， 环境工程， 2010， 硕士

【摘要】 随着城市化进程的加速和环境保护意识的加强,城市污水的处理率逐渐提高,城市污泥的产生量将逐渐增长,如何妥善、科学地处理这些污泥,已成为目前全球共同关注的问题。本文将两种城市污泥分别与煤粉混合（质量比为1:6）磨制污泥水煤浆,在前人研究的基础上主要开展了以下几个方面的研究:1)在实验室内进行污泥水煤浆的成浆性,流变性以及热分析试验,结果表明污泥水煤浆在分散剂添加量为1.2%,稳定剂添加量0.1%时能得到良好的污泥水煤浆产品,表观粘度符合国家水煤浆技术标准。热分析试验结果表明污泥水煤浆较普通水煤浆有较低的着火温度,但是燃烧稳定性略有下降,从综合燃烧特性指数来看污泥水煤浆的S值高于普通水煤浆,说明其燃烧性能更好。2)研究了不同固硫剂对污泥水煤浆流变性的影响,结果表明污泥水煤浆中加入固硫剂后,对污泥水煤浆流变性的影响不大,仍属假塑性流体,但浆体粘度增加。Ca（OH）₂对浆体粘度影响大于CaCO₃,Ca/S比应控制在1.5以下为宜;同时在水平管式炉上进行了污泥水煤浆的燃烧脱硫试验,结果显示本试验条件下污泥水煤浆燃烧固硫的最佳钙硫摩尔比为1.5。3)在浙江大学3.2MW卧式炉上对污泥水煤浆与大同水煤浆进行了对比燃烧试验,分析了煤浆的燃烧特性、结渣特性以及污染物排放特性,结果显示污泥水煤浆燃烧状况较理想,效果不亚于大同烟煤水煤浆。结渣情况不严重,灰渣沉积速率为61.54 g·m^-2min^-1,低于灰分含量较低的大同烟煤水煤浆。污泥水煤浆排烟中SO₂和NO_x的浓度分布为1038 mg/m³和1118 mg/m³,处于较高的水平,这主要与原精煤和污泥中硫及氮含量相对较高有关。污泥水煤浆燃烧后重金属进入大气的份额一般在10%-40%之间,Hg属于强挥发性元素份额较高,为77.84%。更多还原

【Abstract】 The treatment rate of municipal wastewater is increasing with the acceleration of urbanization and and reinforcement of environmental awareness. Thus, the amount of sewage sludge production is increasing How to treat the sludge properly and scientifically has become a common concern. In this paper, two kinds of municipal sewage sludge and coal are mixed （the mass mixing ratio of sludge/coal is 1/6） and milled to prepare the sludge coal water slurry. Based on the previous relevant research, the experimental research of coal water slurry is focused on the following aspects:Firstly, the basic characteristics of sludge coal water slurry such as slurribility、rheology and thermal analysishave been studied, the results showed that the sludge coal water slurry could be a good product when the dispersant ratio was 1.2% and the stabilizer ratio was 0.1%. Moreover the rheology could meet the standards of state technical specification of coal water mixture. The results indicated that the ignition temperature of S-CWS was about 10℃～20℃lower than ordinary CWS. Nevertheless, the combustion stability declined. According to comprehensive burning index S, the combustion characteristics of S-CWS were better than that of CWS.Secondly, the effect of the kinds of sorbents on the slurribility characteristics of sludge coal water slurry had been analyzed. The results showed that sulfur-retention agent had little effect on the rheology of S-CWS, which still appeared as pseudoplastic fluid. Nevertheless, the viscosity of S-CWS increases. The influence of CaCO₃ on the rheological behavior of S-CWS is less than that of Ca（OH）₂, the Ca/S molar ratio should be controlled below 1.5. At the same time, tests of combustion of sludge coal water slurry （S-CWS） were conducted in a fixed bed oven. The results showed that the optimum Ca/S molar ratio of sludge coal water slurry （S-CWS） should be 1.5 under experimental conditions.Thirdly, combustion contrasting test of sludge coal water slurry and Datong coal water slurry were conducted in 3.2MW furnace. Combustion characteristics, slagging characteristics and pollutant emission characteristics were researched. The results showed that the combustion of S-CWS was satisfactory, which is better than Datong bituminous coal-water slurry. The slagging situation was not serious, and the ash deposition rate was 61.54gm^-2 min^-1, which was lower than the Datong CWS. The concentration distribution of SO₂ and NO_x in flue gas was 1038 mg/m and 1118 mg/m³ respectively, which were at high level. The conversion rate of heavy metals into the flue gas was not high, and the share was usually among 10%40%.However, Hg is strong volatile element and the conversion rate of fuel-Hg to gaseous state have reached 77.84%.更多还原