Application and Optimization of Urea Pyrolysis Technology in 1000MW Coal-fired Power Plant

doi:10.12096/j.2096-4528.pgt.20007

Abstract

Abstract:

Urea pyrolysis technology has been applied in many coal-fired power plants with it's advantages of safety and nontoxicity, but there are problems such as sediment plugging in the application. A 1 000 MW unit with urea pyrolysis system was seriously blocked in pyrolysis furnace, export pipeline and ammonia spraying grid, for pyrolytic air lacking caused by the abrasion of bofoster fans, electric heater output limiting, poor atomization effect of spraying guns and so on. According to regular inspection and cleaning, optimizing and adjusting operation parameters, enhancing system control, the problem of blocking was solved. The consumption of urea was reduced, 1.3 million yuan of cost was cut down every year. The reliability and economy of units were increased.

Key words: coal-fired power plant, selective catalytic reduction (SCR), urea pyrolysis, intermediate reaction, sediment, hot primary air

CLC Number:

TK 09

Xiaowei YU, Cuijie KUANG. Application and Optimization of Urea Pyrolysis Technology in 1000MW Coal-fired Power Plant[J]. Power Generation Technology, 2022, 43(2): 367-372.

Figures/Tables 3

References 17

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参数	1 000 MW		900 MW		800 MW		550 MW
参数	#1炉	#2炉	#1炉	#2炉	#1炉	#2炉	#1炉	#2炉
A脱硝反应器入口NO _x 质量浓度/(mg/m³)	280	281	285	245	270	237	257	212
B脱硝反应器入口NO _x 质量浓度/(mg/m³)	246	239	264	205	255	217	245	221
脱硝电加热器入口风量/(m³/h)	7 035	6 337	7 157	6 272	7 111	6 214	7 304	6 271
脱硝热解炉出口温度/℃	377	372	374	374	373	385	380	370
尿素溶液喷射量/(L/h)	554	625	546	475	533	414	360	303
净烟气出口NO _x 质量浓度/(mg/m³)	41	42	39	42	38	43	49	40
脱硝电加热器本体出口温度测点1/℃	524	660	523	635	507	636	459	590
脱硝电加热器本体出口温度测点2/℃	601	660	597	635	579	637	523	559
脱硝电加热器本体出口温度测点3/℃	573	684	566	660	559	665	500	563
锅炉总风量/(t/h)	2 960	2 945	2 729	2 763	2 557	2 507	1 950	2 011
锅炉含氧量/%	2.58	2.31	3.00	2.48	2.80	2.90	4.40	4.70

参数	1 000 MW		900 MW		800 MW		550 MW
参数	#1炉	#2炉	#1炉	#2炉	#1炉	#2炉	#1炉	#2炉
A脱硝反应器入口NO _x 质量浓度/(mg/m³)	280	281	285	245	270	237	257	212
B脱硝反应器入口NO _x 质量浓度/(mg/m³)	246	239	264	205	255	217	245	221
脱硝电加热器入口风量/(m³/h)	7 035	6 337	7 157	6 272	7 111	6 214	7 304	6 271
脱硝热解炉出口温度/℃	377	372	374	374	373	385	380	370
尿素溶液喷射量/(L/h)	554	625	546	475	533	414	360	303
净烟气出口NO _x 质量浓度/(mg/m³)	41	42	39	42	38	43	49	40
脱硝电加热器本体出口温度测点1/℃	524	660	523	635	507	636	459	590
脱硝电加热器本体出口温度测点2/℃	601	660	597	635	579	637	523	559
脱硝电加热器本体出口温度测点3/℃	573	684	566	660	559	665	500	563
锅炉总风量/(t/h)	2 960	2 945	2 729	2 763	2 557	2 507	1 950	2 011
锅炉含氧量/%	2.58	2.31	3.00	2.48	2.80	2.90	4.40	4.70

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