The fate of trace elements in fluidised bed combustion of sewage sludge and wood
The fate of trace elements in fluidised bed combustion of sewage sludge and wood
复制标题
DOI：
10.1016/j.fuel.2006.08.014
复制
发表时间：
2007-03-01
期刊：
影响因子：
7.4
通讯作者：
Andersson, Bengt-Ake
中科院分区：
文献类型：
--
作者：
Elled, Anna-Lena;Amand, Lars-Erik;Andersson, Bengt-Ake
在流化床锅炉中进行了燃烧试验，以研究木材和城市污水污泥混合燃烧过程中微量元素的归宿。该方法是收集燃料和灰分样品，并进行气化（还原）和燃烧（氧化）条件下的热力学平衡计算。在灰烬中发现了微量元素。即使是大部分高挥发性汞也被收集在袋式除尘器的灰中。袋式除尘器的灰比二级旋风除尘器的灰具有更高的表面积，从而提高了汞的捕集能力。没有明显的相关性捕获和参数调查（污泥沉淀剂和石灰添加）。通过平衡计算预测，As、Cd、Hg、Pb、Se、Sb和Tl在氧化条件下在燃烧室中是挥发性的，Hg甚至在过滤器温度（150摄氏度）下也是挥发性的。还原条件促进，在某些情况下比其他情况下，挥发性的砷，镉，铅，锑，硒，铊和锌。对于Cu和Ni观察到相反的效果。数据表明，在气体净化系统中必须包括袋式过滤器，以实现良好的有毒微量元素去除。(c)2006爱思唯尔有限公司版权所有。
Combustion tests have been carried out in a fluidised bed boiler to investigate the fate of trace elements during co-combustion of wood and municipal sewage sludge. The approach was to collect fuel and ash samples and to perform thermodynamic equilibrium calculations for gasification (reducing) and combustion (oxidising) conditions. Trace elements are found in the ash. Even most of the highly volatile Hg is captured in the bag filter ash. The bag filter ash offers higher surface area than the secondary cyclone ash and enhances the capture of Hg. There is no obvious correlation between capture and parameters investigated (sludge precipitation agent and lime addition). As, Cd, Hg, Pb, Se, Sb and Tl are predicted by equilibrium calculations to be volatile in the combustion chamber under oxidising conditions and Hg even at the filter temperature (150 degrees C). Reducing conditions promote, in some case more than others, the volatility of As, Cd, Pb, Sb, Se, Tl and Zn. The opposite effect was observed for Cu and Ni. Data points to the necessity of including bag filter in the gas cleaning system in order to achieve good removal of toxic trace elements. (c) 2006 Elsevier Ltd. All rights reserved.