【作者】 乔军师；

【导师】 胡金榜；

【作者基本信息】 天津大学 ， 化工过程机械， 2005， 硕士

【摘要】 本文根据目前NOX废气的污染现状,介绍了现有各种脱氮技术的基本原理和特点,并重点论述了NOX空气氧化与液相吸收法的反应机理。用工业氮气和NO按不同比例混合得到不同浓度的模拟NOX废气,补充空气和模拟废气按体积比1:1混合,补充空气中的氧气在氧化塔内对模拟废气中的NO进行氧化。通过控制模拟废气和补充空气的流量,来控制NOX在氧化塔内的停留时间,即氧化时间τ。测得氧化塔出口的NOX浓度和氧化度α,分析NOX浓度,氧化度α和氧化时间τ三者之间的关系。对氧化后的NOX废气在室温(15~20℃)下分别用酸性,中性,碱性尿素溶液和浓硫酸溶液进行吸收实验。测得各种吸收液对不同浓度和氧化度的NOX废气的吸收率η,并找出可使吸收塔正常工作的操作条件,如:液气比,填料性能,载液量等。分析稳定工况下,各种吸收液对NOX的吸收率η随NOX的浓度和氧化度(氧化时间)的变化情况,为其工程应用提供了实验依据。并对以上四种吸收液的吸收效果进行对比,结合用户需求,选择经济合理的吸收液类型。根据某化纤厂硝化工段的NOX废气的排放情况进行工程预测,提出了NOX空气氧化碱性尿素溶液吸收和NOX空气氧化浓硫酸吸收两套治理方案。结合工艺实验结果分别对两套方案的氧化塔和吸收塔的形式和尺寸进行了初步设计。更多还原

【Abstract】 According to the current situation of NOX pollution, the theory andcharacteristic of several existing NOX pollution control measures are introduced,the mechanism of air oxidation of NO and absorption of NOX with severalsolutions are discussed in this Paper. In order to stimulate the real condition ofNOX waste gas expelled by chemical plants, industrial N2 and pure NO are mixedat different ratios in the experiment to get stimulated NOX waste gas with differentconcentration. NO in the waste gas is oxidized by O2 of the injected air in theoxidation tower, and the molar ratio of injected air to waste gas is 1:1. Oxidationtime is controlled by the flow rate of the waste gas and injected air. The relation ofconcentration of NOX, ratio of oxidation and time for oxidation is analyzed.Oxidized NOX gas is absorbed with urea solution, mixed solution of urea andhydrochloric acid, mixed solution of urea and sodium hydroxide, oil of vitriolrespectively with temperature range from 15~20℃. The absorptivity of NOX withdifferent solutions in packed column is thoroughly analyzed, essential data isobtained for the industrial application. Two feasible methods for the reduction ofNOX expelled by a chemical plant is proposed, one is air oxidation and absorptionof NOX with mixed solution of urea and sodium hydroxide, the other is airoxidation and absorption of NOX with oil of vitriol, a prediction of the equipmentswill be used in this project is made.更多还原