Simultaneous reduction of NO x  and CO emissions in domestic decoupling coal-fired stoves

doi:10.11949/j.issn.0438-1157.20181327

Abstract

Abstract:

A typical civil decoupling coal-fired stove has two parallel furnaces, called a pyrolysis chamber and a combustion chamber, which are connected at the bottom, coal is introduced from the upper part of the pyrolysis chamber, and air is introduced through the inclined grate at the bottom of the pyrolysis chamber. Based on the profound understanding of both the nitrogen transformation route in coal combustion and the characteristics of gas flow circulation in decoupling stoves, the mechanisms of simultaneous reduction of NO _x and CO emissions in domestic decoupling coal-fired stoves were qualitatively analyzed in this paper. The influences of draft type and coal property on NO and CO emissions were experimentally studied further. The results indicate that the simultaneous suppression of NO _x and CO emissions in a domestic decoupling coal-fired stove can be mainly attributed to its unique geometry structure and draft type. Burning clean briquettes in decoupling stoves helps to reduce pollutant emissions significantly.

Key words: coal combustion, pollution, nitrogen oxide, carbon monoxide, domestic stove

摘要：

典型民用解耦燃煤炉具有底部连通的两个分别被称为热解室和燃烧室的并列炉膛，煤炭从热解室上部加入，空气通过热解室底部的倾斜炉排引入。结合煤炭燃烧过程中的氮转移路线与解耦炉中的气体循环流动特征，定性分析了民用解耦燃煤炉中的NO _x 和CO同时减排机理，并在此基础上对配风和煤种等因素对NO和CO排放的影响进行了定量实验研究。结果表明，民用解耦燃煤炉特有的结构特征和通风方式有利于NO _x 和CO的同时减排，解耦炉具与洁净型煤匹配可显著降低综合污染物排放。

关键词: 煤燃烧, 污染, 氮氧化物, 一氧化碳, 民用炉具

CLC Number:

TQ 534

Jian HAN, Xinhua LIU, Jingdong HE, Honglin LI, Nan ZHANG. Simultaneous reduction of NO _x and CO emissions in domestic decoupling coal-fired stoves[J]. CIESC Journal, 2019, 70(5): 1991-1998.

韩健, 刘新华, 何京东, 李虹嶙, 张楠. 民用解耦燃煤炉中的NO _x 和CO同时减排[J]. 化工学报, 2019, 70(5): 1991-1998.

Figures/Tables 10

Fig.1 Schematic diagram of a typical domestic decoupling coal-fired stove

Table 1 Properties of three kinds of briquettes from bituminous coal

燃料	工业分析（收到基）/%				元素分析（收到基）/%					收到基低位发热量/(MJ/kg)
燃料	水分	挥发分	固定碳	灰分	碳	氢	氧	氮	硫	收到基低位发热量/(MJ/kg)
1#	5.0	22.7	51.5	20.8	61.0	3.4	7.9	1.1	0.8	22.55
2#	2.4	26.8	34.2	36.6	46.4	3.2	9.6	0.9	0.9	17.84
3#	2.2	29.2	48.9	19.7	63.7	4.5	8.1	1.2	0.6	25.18

Fig.2 Fuel N transformation route in decoupling stoves

Fig.3 Gas streamline in a decoupling stove

Fig.4 NO concentration distribution in a decoupling stove under different reducing effects

Fig.5 CO concentration distribution in a decoupling stove

Fig.6 Influences of air regulator Ⅰ on pollutant emissions

Fig.7 Influences of air regulator Ⅱ on pollutant emissions

Fig.8 Pollutant emissions during stable combustion of three kinds of briquettes

Fig.9 Pollutant emissions during ignition, flaming and stable combustion

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