The mercury removals by existing pollution control devices and the mass balances of mercury in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent.All ...The mercury removals by existing pollution control devices and the mass balances of mercury in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent.All the plants are equipped with a cold-side electrostatic precipitator （ESP） and a wet flue gas desulfurization （FGD） in series.During the course of coal stream,the samples,such as coal,bottom ash,fly ash,gypsum and flue gas,were collected.The Hg concentrations in coals were measured by CVAAS after appropriate preparation and acid digestion.Other solid samples were measured by the RA-915 ＋ Zeeman Mercury Spectrometer.The vapor phase Hg was collected by a sorbent trap from flue gas and then measured using CVAAS followed by acid leaching.The mercury mass balances were estimated in this study were 91.6%,77.1%,118% and 85.8% for the four power plants,respectively.The total Hg concentrations in the stack gas were ranged from 1.56–5.95 μg/m 3.The relative distribution of Hg in bottom ash,ESP,WFGD and stack discharged were ranged between 0.110%–2.50%,2.17%–23.4%,2.21%–87.1%,and 21.8%–72.7%,respectively.The distribution profiles were varied with the coal type and the operation conditions.The Hg in flue gas could be removed by ESP and FGD systems with an average removal efficiency of 51.8%.The calculated average emission factor was 0.066 g/ton and much lower than the results obtained ten years ago.展开更多
利用Grimm 1.108、Thermo RP 1 400a以及TSP等仪器于2009年1月至2010年2月对塔克拉玛干沙漠腹地塔中不同高度沙尘气溶胶质量浓度进行连续观测,结合天气资料进行分析。结果表明:①80m高度PM10质量浓度最高,80m高度PM2.5和PM1.0质量浓度...利用Grimm 1.108、Thermo RP 1 400a以及TSP等仪器于2009年1月至2010年2月对塔克拉玛干沙漠腹地塔中不同高度沙尘气溶胶质量浓度进行连续观测,结合天气资料进行分析。结果表明:①80m高度PM10质量浓度最高,80m高度PM2.5和PM1.0质量浓度明显低于4m高度PM10,80m高度PM1.0质量浓度最低。频繁的沙尘天气是影响不同粒径的沙尘气溶胶浓度含量的主要因素。②夜间至日出,PM质量浓度逐渐降低,最低基本上出现在08:00,随后质量浓度逐渐增大,18:00前后浓度达到最高值,然后又逐步降低。其规律与风速的昼夜变化完全一致。③TSP月平均质量浓度高值主要集中在3—9月,其中4月和5月浓度最高,随后逐渐减低。3—9月也是PM月平均质量浓度的高值区域,4m高度PM10月平均质量浓度最高发生在5月,其浓度为846.0μg.m-3。80m高度PM10浓度远高于PM2.5和PM1.0浓度,PM2.5和PM1.0浓度相差较小。风沙天气对大气中的不同粒径粒子的浓度含量影响较大,风沙天气越多,粗颗粒含量越高,反之则细颗粒越多。④沙尘天气过程中不同粒径沙尘气溶胶质量浓度变化具有晴天<浮尘天气<扬沙天气<沙尘暴天气的规律。各种沙尘天气中,PM10/TSP表现为晴好天气高于浮尘天气,浮尘天气远高于扬沙和沙尘暴天气。⑤沙尘天气过程中,沙尘气溶胶浓度随着粒径的减小,浓度逐渐降低。不同高度、不同粒径的沙尘气溶胶质量浓度每隔3～4d形成一个峰值区,与每隔3～4d出现沙尘天气强度增强过程直接相关。展开更多
基金supported by the National High-Tech Research and Development Program (863) of China(No.2007AA06Z340)
文摘The mercury removals by existing pollution control devices and the mass balances of mercury in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent.All the plants are equipped with a cold-side electrostatic precipitator （ESP） and a wet flue gas desulfurization （FGD） in series.During the course of coal stream,the samples,such as coal,bottom ash,fly ash,gypsum and flue gas,were collected.The Hg concentrations in coals were measured by CVAAS after appropriate preparation and acid digestion.Other solid samples were measured by the RA-915 ＋ Zeeman Mercury Spectrometer.The vapor phase Hg was collected by a sorbent trap from flue gas and then measured using CVAAS followed by acid leaching.The mercury mass balances were estimated in this study were 91.6%,77.1%,118% and 85.8% for the four power plants,respectively.The total Hg concentrations in the stack gas were ranged from 1.56–5.95 μg/m 3.The relative distribution of Hg in bottom ash,ESP,WFGD and stack discharged were ranged between 0.110%–2.50%,2.17%–23.4%,2.21%–87.1%,and 21.8%–72.7%,respectively.The distribution profiles were varied with the coal type and the operation conditions.The Hg in flue gas could be removed by ESP and FGD systems with an average removal efficiency of 51.8%.The calculated average emission factor was 0.066 g/ton and much lower than the results obtained ten years ago.
文摘利用Grimm 1.108、Thermo RP 1 400a以及TSP等仪器于2009年1月至2010年2月对塔克拉玛干沙漠腹地塔中不同高度沙尘气溶胶质量浓度进行连续观测,结合天气资料进行分析。结果表明:①80m高度PM10质量浓度最高,80m高度PM2.5和PM1.0质量浓度明显低于4m高度PM10,80m高度PM1.0质量浓度最低。频繁的沙尘天气是影响不同粒径的沙尘气溶胶浓度含量的主要因素。②夜间至日出,PM质量浓度逐渐降低,最低基本上出现在08:00,随后质量浓度逐渐增大,18:00前后浓度达到最高值,然后又逐步降低。其规律与风速的昼夜变化完全一致。③TSP月平均质量浓度高值主要集中在3—9月,其中4月和5月浓度最高,随后逐渐减低。3—9月也是PM月平均质量浓度的高值区域,4m高度PM10月平均质量浓度最高发生在5月,其浓度为846.0μg.m-3。80m高度PM10浓度远高于PM2.5和PM1.0浓度,PM2.5和PM1.0浓度相差较小。风沙天气对大气中的不同粒径粒子的浓度含量影响较大,风沙天气越多,粗颗粒含量越高,反之则细颗粒越多。④沙尘天气过程中不同粒径沙尘气溶胶质量浓度变化具有晴天<浮尘天气<扬沙天气<沙尘暴天气的规律。各种沙尘天气中,PM10/TSP表现为晴好天气高于浮尘天气,浮尘天气远高于扬沙和沙尘暴天气。⑤沙尘天气过程中,沙尘气溶胶浓度随着粒径的减小,浓度逐渐降低。不同高度、不同粒径的沙尘气溶胶质量浓度每隔3～4d形成一个峰值区,与每隔3～4d出现沙尘天气强度增强过程直接相关。
