发电机组水汽系统有机物热分解规律研究
|
摘要
电厂补给水中残余的有机物进入热力系统后,会在高温高压条件下分解,生成甲酸、乙酸等低分子有机酸,这会引起水汽氢电导率异常升高,pH值降低,造成热力设备腐蚀。本文使用高压釜作为反应器,用腐植酸配制不同质量浓度的有机物溶液,从温度、分解时间、有机物质量浓度等方面实验研究高温高压条件下有机物热分解产物的变化规律。结果表明:有机物在高温高压条件下的分解产物主要为甲酸和乙酸,随着温度的升高和分解时间的延长,乙酸质量浓度增大,但由于甲酸的热稳定性较低,会发生分解导致质量浓度逐渐降低;氧对有机物的热稳定性有较大的影响,氧的存在会降低有机物和甲酸的热稳定性,促进有机物和甲酸的分解,降低水中有机酸的质量浓度。
The organic matters in make-up water entering the water-steam cycle of a power plant will decompose at high temperatures and produce low molecular organic acids such as formic acid and acetic acid, which causes the steam cation conductivity rises and the pH value reduces, resulting in corrosion of thermal equipments. By using autoclave as the reactor and humic acid as the organic solution, the decomposition characteristics of organic matters at high temperatures were experimentally studied, and the influence of temperature, retention time and organic concentration on decomposition products from the humic acid was investigated. The results show that, the major decomposition products were acetic acid and formic acid, and the concentration of acetic acid increased with the temperature and retention time. However, the concentration of formic acid decreased due to its low thermal stability. Oxygen had great effect on the thermal stability of organic matters, the presence of oxygen decreased the thermal stability of organic matters and formic acid, improved the decomposition of organic matters and formic acid, and reduced the concentration of organic acids in water.
The organic matters in make-up water entering the water-steam cycle of a power plant will decompose at high temperatures and produce low molecular organic acids such as formic acid and acetic acid, which causes the steam cation conductivity rises and the pH value reduces, resulting in corrosion of thermal equipments. By using autoclave as the reactor and humic acid as the organic solution, the decomposition characteristics of organic matters at high temperatures were experimentally studied, and the influence of temperature, retention time and organic concentration on decomposition products from the humic acid was investigated. The results show that, the major decomposition products were acetic acid and formic acid, and the concentration of acetic acid increased with the temperature and retention time. However, the concentration of formic acid decreased due to its low thermal stability. Oxygen had great effect on the thermal stability of organic matters, the presence of oxygen decreased the thermal stability of organic matters and formic acid, improved the decomposition of organic matters and formic acid, and reduced the concentration of organic acids in water.
引文
[1]王国蓉.供热机组水汽系统有机物行为的研究[J].华电技术,2017,39(3):5-8.WANG Guorong.Heat supply unit water-steam organic matter behavior study[J].Huadian Technology,2017,39(3):5-8.
[2]金绪良,李永立,王应高,等.电厂水汽系统有机物含量对氢电导率影响试验研究[J].工业水处理,2016,36(12):67-69.JIN Xuliang,LI Yongli,WANG Yinggao,et al.Experimental study on the influence of organic matter content in the water vapor system of a power plant on hydrogen conductivity[J].Industrial Water Treatment,2016,36(12):67-69.
[3]BODMER M.Acid corrosion in steam turbines[J].Combustion,1978(49):35-43.
[4]吴昊.电厂中有机物的来源、特征及去除措施[J].重庆电力高等专科学校学报,2016,21(3):47-49.WU Hao.Analysis of the sources,characteristics and removal of organic matters in the pwer plant[J].Journal of Chongqing Electric Power College,2016,21(3):47-49.
[5]丁桓如.水中有机物质分类问题探讨及溶解态有机物的测定[J].热力发电,1997,26(2):19-23.DING Huanru.On classification of organic matters in water and their determination in solution state[J].Thermal Power Generation,1997,26(2):19-23.
[6]LUUKKONEN T,TOLONEN E T,RUNTTI H,et al.Removal of total organic carbon(TOC)residues from power plant make-up water by activated carbon[J].Journal of Water Process Engineering,2014,3:46-52.
[7]MIAO Y E,DING H R.Efficiency of organic matters removal of each processing unit in water treatment processes[J].Water Purification Technology,2012,31:27-33.
[8]WANG J N,LI A M,ZHOU Y,et al.Study on the influence of humic acid of different molecular weight on basic ion exchange resin’s adsorption capacity[J].Chinese Chemical Letters,2009,20(12):1478-1482.
[9]HUBER S A.The behaviour of natural organic matter in water treatment and the water-steam cycle:deeper insights[J].Power Plant Chemistry,2016(8):105-116.
[10]LUUKKONEN T,TOLONEN E T,RUNTTI H,et al.Reduction of organic carbon in demineralized make-up water with activated carbon filtration[J].Power Plant Chemistry,2012,14(2):112-119.
[11]SCHONFELDER T,KEIL U.Biological adsorptive process for removal of organics from raw water as pre-treatment of a demineralisation plant[J].VGB Power Tech,2002,82:100-105.
[12]王亚军,马军.水体环境中天然有机质腐殖酸研究进展[J].生态环境学报,2012,21(6):1155-1161.WANG Yajun,MA Jun.Research advances of humic acid in aquatic environments[J].Ecology and Environmental Sciences,2012,21(6):1155-1161.
[13]林奇峰,刘明.有机物对供热发电机组水汽品质的影响[J].电力与电工,2013,33(6):51-55.LIN Qifeng,LIU Ming.The influence of organics on steam quality of heat supply generator units[J].Electric Power and Electrical Engineering,2013,33(6):51-55.
[14]杨波.电站锅炉补给水中腐植酸的去除研究[D].长沙:长沙理工大学,2009:3-5.YANG Bo.Study on remove humic acid in power plant boiler make-up water[D].Changsha:Changsha University of Science&Techonology,2009:3-5.
[15]MOED D H,VERLIEFDE A R D,HEIJMAN S G J,et al.Organic acid formation in steam-water cycles:Influence of temperature,retention time,heating rate and O2[J].Applied Thermal Engineering,2014,65:194-200.
[2]金绪良,李永立,王应高,等.电厂水汽系统有机物含量对氢电导率影响试验研究[J].工业水处理,2016,36(12):67-69.JIN Xuliang,LI Yongli,WANG Yinggao,et al.Experimental study on the influence of organic matter content in the water vapor system of a power plant on hydrogen conductivity[J].Industrial Water Treatment,2016,36(12):67-69.
[3]BODMER M.Acid corrosion in steam turbines[J].Combustion,1978(49):35-43.
[4]吴昊.电厂中有机物的来源、特征及去除措施[J].重庆电力高等专科学校学报,2016,21(3):47-49.WU Hao.Analysis of the sources,characteristics and removal of organic matters in the pwer plant[J].Journal of Chongqing Electric Power College,2016,21(3):47-49.
[5]丁桓如.水中有机物质分类问题探讨及溶解态有机物的测定[J].热力发电,1997,26(2):19-23.DING Huanru.On classification of organic matters in water and their determination in solution state[J].Thermal Power Generation,1997,26(2):19-23.
[6]LUUKKONEN T,TOLONEN E T,RUNTTI H,et al.Removal of total organic carbon(TOC)residues from power plant make-up water by activated carbon[J].Journal of Water Process Engineering,2014,3:46-52.
[7]MIAO Y E,DING H R.Efficiency of organic matters removal of each processing unit in water treatment processes[J].Water Purification Technology,2012,31:27-33.
[8]WANG J N,LI A M,ZHOU Y,et al.Study on the influence of humic acid of different molecular weight on basic ion exchange resin’s adsorption capacity[J].Chinese Chemical Letters,2009,20(12):1478-1482.
[9]HUBER S A.The behaviour of natural organic matter in water treatment and the water-steam cycle:deeper insights[J].Power Plant Chemistry,2016(8):105-116.
[10]LUUKKONEN T,TOLONEN E T,RUNTTI H,et al.Reduction of organic carbon in demineralized make-up water with activated carbon filtration[J].Power Plant Chemistry,2012,14(2):112-119.
[11]SCHONFELDER T,KEIL U.Biological adsorptive process for removal of organics from raw water as pre-treatment of a demineralisation plant[J].VGB Power Tech,2002,82:100-105.
[12]王亚军,马军.水体环境中天然有机质腐殖酸研究进展[J].生态环境学报,2012,21(6):1155-1161.WANG Yajun,MA Jun.Research advances of humic acid in aquatic environments[J].Ecology and Environmental Sciences,2012,21(6):1155-1161.
[13]林奇峰,刘明.有机物对供热发电机组水汽品质的影响[J].电力与电工,2013,33(6):51-55.LIN Qifeng,LIU Ming.The influence of organics on steam quality of heat supply generator units[J].Electric Power and Electrical Engineering,2013,33(6):51-55.
[14]杨波.电站锅炉补给水中腐植酸的去除研究[D].长沙:长沙理工大学,2009:3-5.YANG Bo.Study on remove humic acid in power plant boiler make-up water[D].Changsha:Changsha University of Science&Techonology,2009:3-5.
[15]MOED D H,VERLIEFDE A R D,HEIJMAN S G J,et al.Organic acid formation in steam-water cycles:Influence of temperature,retention time,heating rate and O2[J].Applied Thermal Engineering,2014,65:194-200.