混煤燃烧减少细微颗粒物生成的实验研究  

EXPERIMENTAL STUDY OF COAL BLEND COMBUSTION FOR FINE PARTICULATES REDUCTION

作　　者：周科[1] 徐明厚[1] 于敦喜[1] 温昶[1] 占中华[1] 姚洪[1] 

机构地区：[1]华中科技大学煤燃烧国家重点实验室,湖北武汉430074

出　　处：《工程热物理学报》2011年第2期349-352,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.50720145604;No.50721005;No.51076051)

摘　　要：本文将一种褐煤和一种烟煤进行不同混合比例(9:1、7:3、1:1、3:7和1:9)和不同燃烧气氛(O_2/N_2和O_2/CO_2气氛)的沉降炉燃烧实验,采用低压撞击器(LPI)对燃烧生成的颗粒物进行收集,并对所收集的颗粒物开展生成浓度、元素组成等分析,研究了混煤燃烧减少细微颗粒物生成的作用机理及混煤比例、燃烧气氛对其的影响。研究结果表明,两种实验煤粉混合燃烧后,PM_1的生成相比于理论计算值有不同程度的减少,说明不同煤种间矿物元素的交互作用抑制了燃煤过程中PM_1的生成。煤粉混合比例和燃烧气氛对PM_1生成的抑制程度有重要影响。在本实验研究中,当褐煤与烟煤的混合质量比为7:3时,PM_1的生成所受抑制程度最大;与O_2/N_2燃烧气氛相比,O_2/CO_2燃烧气氛下,混煤燃烧后矿物元素交互作用减弱,PM_1生成所受抑制程度降低。与理论计算值相比,混煤后PM_1中的Ca、Fe元素生成浓度减少,而PM_(10+)中Ca、Fe、Si、Al元素生成浓度则增多,褐煤燃烧过程中生成的Ca、Fe等易气化元素与烟煤中大量硅铝酸盐的交互作用是混煤燃烧后PM_1生成减少的主要途径。This study addressed the mechanism of coal blend combustion for fine particulates reduction, and the impact of blend ratio and combustion atmosphere on the reduction properties. Coal blends from a lignite and a bituminous coal, with different blend ratios （9：1, 7：3, 5：5, 3：7, 1：9） and different combustion atmosphere （O2/N2 and O2/CO2 atmosphere.）, were combusted in a drop tube furnace to analyze the concentration and element composition of the particulate matter generated, which collected by a low pressure impactor （LPI）. The results showed that, compared to the theoretical calculated values, the PM1 generation reduced after blended coal combustion, which indicated that the mineral interaction had a great effect on PM1 reduction. Both the blend ratio and combustion atmosphere played important roles in the suppression of PM1 generation. In this experimental study, PM1 generation suffered a great degree of suppression at blend ratio of 7：3. Compared to the O2/N2 combustion, the interaction of minerals weakened under O2/CO2 combustion, thus the suppression of PM1 generation declined after coal blending. Compared to the theoretical calculated values, the concentration and compositions of Ca, Fe in PMldecreased, but the concentration of Ca, Fe, Si and A1 in coarse particulates （PM10＋） increased after blended coal combustion. The interactions between the volatile dement Ca, Fe in lignite and aluminosilieate in bituminous coal is thought to be the main way to suppress the PM1 generation.

关 键 词：煤燃烧 混煤 颗粒物 O2/CO2燃烧 交互作用 

分 类 号：TK228[动力工程及工程热物理—动力机械及工程]