竹园污泥焚烧污染物排放特性的试验研究

选取上海竹园污泥,将原始污泥样品分为全干污泥、均匀干化污泥(含水率10%)和干湿混合污泥(含水率20%,干湿污泥质量比例为10∶3)三种样品,分别送入小型流化床焚烧炉中焚烧。试验研究了全干污泥在750℃、850℃、950℃三个工况下的燃烧特性,并研究了均匀干化污泥和干湿混合污泥在850℃工况下的燃烧特性。研究发现,上海竹园污泥在小型流化床焚烧炉中燃烧时,排放的主要常规污染物包括CO、SO2、NOx、HCl等以及二噁英和Cd、Hg、Pb等重金属。不同燃烧温度和含水率对污染物的排放有一定影响,提高燃烧温度,CO、SO2、NOx、HCl等的排放基本呈现出下降趋势,而烟气中Pb的排放随着温度上升而升高,相同燃烧温度下含水率升高能降低二噁英的排放总量,随着含水率的提高飞灰中重金属含量有所降低,而底渣中重金属含量呈上升趋势。

Experimental study on emission characteristics of pollutants during Zhuyuan sludge combustion

Shanghai Zhuyuan sludge was selected and sorted for three kinds: absolute dried sludge,uniformed dried sludge(the moisture content: 10%) and the mixture of dried sludge and wet sludge(the moisture content: 20%).Then they were sent into a lab-scale fluidized bed incinerator for combustion.The characteristics of pollutants emission from absoluted dried sludge combustion was studied at temperature of 750℃,850℃ and 950℃.Also the characteristics of pollutants emission from uniformed sludge combustion and the sludge mixture combustion was studied at the temperature of 850℃.It was indicated that the major pollutants included CO,SO2,NOx,HCl,dioxins and some heavy metals like Cd,Hg and Pb during Zhuyuan sludge combustion in the lab-scale fluidized bed incinerator.Different combustion temperatures and moisture contents have impact on pollutants emission.Raising the combustion temperature will reduce the emission of CO,SO2,NOx and HCl,while the emission of Pb in flue gas will increase with the temperature increasing.At the same combustion temperature raising the moisture content will reduce the total amount of dioxins emission and the heavy metals in fly ash while it will increase in the bottom slag.