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分析了国内燃煤电厂及煤矸石电厂锅炉烟气排放现状和存在的问题 ,针对本厂特点 ,选用了高压静电除尘、石灰石 -石膏法脱硫、水力除尘清灰闭路循环等烟气治理工艺 ,改造原有的烟气处理工艺 ,取得了令人满意的效果。 相似文献
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在目前实施可持续发展战略的政策下,电厂排污成为社会关注的环境问题。某电厂300MW燃煤发电机组采用的是双室三电场除尘器,其外排烟气中烟尘排放浓度难以稳定达到环保部最新排放标准要求,因此对现有机组进行除尘改造势在必行,本文就该电厂燃煤发电机组除尘改造方案进行探讨。 相似文献
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为了降低燃煤电厂脱硫后烟气中的含湿量,有效回收烟气中的水分及余热,同时解决因饱和湿烟气中水蒸气凝结引起的烟囱腐蚀、"烟囱雨"及"白烟"等问题,分析了湿烟气的热力特点及能量分布的形式,介绍并对比了冷凝法、溶液吸收法及膜法3种较为可行的湿烟气除湿工艺,论述了其技术特点、研究现状、不足及研究方向。研究表明,脱硫后湿烟气中每千克干烟气含湿量约80 g,70%余热以水蒸气潜热的形式存在,冷凝法现阶段相对较为成熟,但吸收法除湿潜力更高、膜法系统简单稳定可靠,具有非常好的应用前景,是烟气除湿工艺研究的趋势;低品位余热的经济利用途径将是燃煤电厂烟气除湿技术的一个重要研究方向。 相似文献
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宜化引进孟山都公司动力波电石渣烟气脱硫技术湖北宜化集团有限责任公司最近投资3000多万元, 引进美国孟山都公司动力波洗涤器技术,利用公司内聚氯乙烯生产过程的副产电石渣,对电厂烟气进行脱硫除尘净化,运行成本控制在0.025元/(kW·h)以下。这项技术不仅实现了废物再利用,而且解决了燃煤电厂脱硫运行费用高的难题。 (肖渠) 相似文献
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介绍了中国石化北京燕山分公司针对220 t/h水煤浆锅炉烟气的特点和脱硝的要求,选取了选择性催化还原(SCR)技术对该锅炉尾部烟气实施脱硝治理。通过对脱硝方案的研究,确定了脱硝的工艺流程和脱硝的有关工艺参数。SCR反应器操作温度控制在320~370 ℃范围内,氨与空气的混合体积比约为5∶95,SO2转化率小于1%,SCR反应区压降小于1000 Pa,NH3的逃逸率小于3%。项目通过建设、试运行和相关测试,锅炉的脱硝效果达到了北京市地方环保规定的标准。该项目对引进国外技术结合国内大型锅炉的特点进行锅炉烟气脱硝治理有重要意义。 相似文献
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Nicole Brueggemann Tim Puehmeier Ralf Fiekens Franz-Josef Richardt Manfred Salvermoser 《臭氧:科学与工程》2017,39(3):196-201
The efficiency of ozone generators is determined by many factors. Operating conditions such as feed gas quality and especially cooling conditions are of utmost importance. Cooling of ozone generators is absolutely necessary, since ozone destruction reactions increase exponentially with temperature. The most common way to cool an ozone generator is water flowing in close contact to the electrodes. The heat removal out of the discharge gap depends on different parameters. Electrical input power, cooling water flow conditions, electrode geometry and material properties are some of them. Simultaneously lowering cooling water temperature, applied power density and gap width, leads to a lower gas temperature in the discharge gap and thus to increased ozone production efficiency. Minimizing the temperature difference between the cooling water inlet and outlet improves the ozone production efficiency as well. This measure, however, results in high cooling water flows and requires additional cooling water chilling, resulting in higher operational costs and capital expenses. Cooling associated costs rise disproportionally with increasing cooling water flow. Simultaneously, energy consumption of ozone generators decreases as the average cooling water temperature goes down. As a result, there exists an optimum between the operational and capital expenses for the combination of ozone generator and cooling water system related expenses, offering significant cost savings for the customer. 相似文献
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The selective catalytic reduction(SCR)of NOxwith NH3has been proven to be an efficient technology for NOx conversion to N2.However,the catalysts used for SCR usually suffer from the problem of sulfur poisoning which seriously limits their practical application.This review summarized sulfur poisoning mechanisms of various SCR deNOxcatalysts and strategies to reduce deactivation caused by SO2such as doping metals,control-ling the structures and morphologies of the catalysts,and selecting appropriate supports.The methods and procedures of catalysts preparation and the reaction conditions also have effect on SO2-resistance of the catalysts. Several novel catalyst systems that exhibited good SO2resistance are also introduced.This paper could provide guidance for the development of highly efficient sulfur-tolerant deNOxcatalysts. 相似文献
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分析了搅拌塔式反应器(SCR)中多级冷却盘管隔板的传热特性,用稳态和非稳态的传热方法进行了实验研究。提出了同时考察拌雷诺数和轴向液流雷诺数影响的SCR中多级冷却盘管隔板表面传热膜系数的关联式。研究结果表明,对于SCR中冷却盘管隔板表面的传热膜系数,轴向液轩诺系数的影响与搅拌雷诺数的影响相比具有同等的重要性。 相似文献
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采用Aspen Plus软件对烟气污染控制单元进行模拟,以电厂实际运行数据验证模型的正确性,建模过程中考虑SO3转化和烟气中烟尘浓度的变化,并通过影响因素分析考察操作参数对污染物脱除效果的影响。结果表明,在选择性催化还原(SCR)脱硝过程中,部分SO2转化为SO3,除尘过程中飞灰对SO3有吸附作用,脱硫塔与除尘器对SO3和灰分脱除具有协同作用;SCR脱硝过程的最佳氨氮摩尔比范围为0.8~1.0,氨氮比低于0.6、反应温度低于400℃时,SO3浓度呈上升趋势;湿法脱硫过程中,入口烟气温度上升会阻碍SO2吸收和SO3去除;湿式除尘过程中,除尘效率随温度升高而降低,随气体流速增加先升高后降低,最佳流速为0.8~1.2 m/s。 相似文献
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The catalytic activity of carbon nanotubes-supported vanadium oxide (V2O5/CNTs) catalysts in the selective catalytic reduction (SCR) of NO with NH3 at low temperatures (≤250 °C) was investigated. The effects of V2O5 loading, reaction temperature, and presence of SO2 on the SCR activity were evaluated. The results show that V2O5/CNTs catalysts exhibit high activity for NO reduction with NH3 at low-temperatures. The catalysts also show very high stability in the presence of SO2. More interestingly, their activities are significantly promoted in-stead of being poisoned by SO2. The promoting effect of SO2 is distinctly associated with V2O5 loading, particularly maximized at low V2O5 loading, which indicated the role of CNTs support in this effect. The promoting effect of SO2 at low temperatures suggests that V2O5/CNTs catalysts are promising catalytic materials for low-temperature SCR reactions. 相似文献
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H2O和SO2对Mn-Fe/MPS催化剂用于NH3低温还原NO的影响 总被引:5,自引:2,他引:3
研究了H2O和SO2对Mn-Fe/MPS催化剂低温下选择性催化NH3还原(SCR)NO的影响. 结果表明,Mn-Fe/MPS催化剂具有良好的催化活性,在空速为20000 h-1、反应温度433 K时,NO的SCR转化率达99.1%. 在反应温度低于413 K时,水蒸汽(10%, j)在一定程度上降低了催化活性;超过433 K时,这种影响可完全消除,NO的SCR转化率达到97.8%以上. 低浓度SO2(100′10-6)存在条件下,443 K时催化效率仍可稳定在97.2%. 在水和SO2共存的情况下,生成的硫酸盐和亚硫酸盐沉积在催化剂表面导致催化剂逐渐失活,FT-IR测试也表明伴随SCR反应生成了硫酸铵. 提高反应温度可以延缓催化剂的失活. 此外还研究了不同活化温度对催化剂活性恢复的影响,结果表明,当活化温度达到773 K时,催化剂活性可以完全恢复. 本研究中的催化剂的综合性能优于目前文献报道的其他催化剂. 相似文献
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Ammonium bisulfate (ABS) is a viscous compound produced by the escape NH3 in the NO reduction process and SO3 in the flue gas at a certain temperature, which can cause the ash corrosion of the air preheater in coal-fired power plants. Therefore, it is essential to study the formation temperature of ABS to prevent the deposition of ABS in air preheaters. In this paper, the SO3 reaction kinetic model is used to analyze the SO3 generation process from coal combustion to the selective catalytic reduction (SCR) exit stage, and the kinetic model of NO reduction is used to analyze the NH3 escape process. A prediction model for calculating the ABS formation temperature based on the S content in coal and NO reduction parameters of the SCR is proposed, solving the difficulty of measuring SO3 concentration and NH3 concentration in the previous calculation equation of ABS formation temperature. And the reliability of the model is verified by the actual data of the power plant. Then the influence of S content in coal, NH3/ NOx molar ratio, different NOx concentrations at SCR inlet, and NO removal efficiency on the formation temperature of ABS are analyzed. 相似文献
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V2O5-MoO3/TiO2 催化剂的NOx选择性催化还原及SO2氧化活性 总被引:2,自引:0,他引:2
采用浸渍法以TiO2为载体制备V2O5-MoO3/TiO2 选择性催化还原催化剂,研究V2O5和MoO3负载量对于催化剂选择性催化还原反应及SO2氧化活性的影响,并考察氧含量、氨氮物质的量比和反应空速对3%V2O5-6%MoO3/TiO2催化剂选择性催化还原脱硝活性的影响。结果表明,随着催化剂中V2O5负载质量分数增加,V2O5-MoO3/TiO2 催化剂的选择性催化还原活性和SO2氧化活性均呈上升趋势。MoO3的负载对催化剂的SO2氧化活性有明显抑制作用。MoO3负载质量分数超过9%,制备的催化剂既保持较高的低温选择性催化还原活性,又使选择性催化还原反应中的SO2转化率小于1%。 相似文献