DEVELOPMENT OF A NOVEL TECHNOLOGY FOR AIR POLLUTION CONTROL BY USING ELECTROSPRAY METHOD

电喷雾法空气污染治理新技术的开发

• 批准号: 08555182
• 负责人: HARANO Azuchi
• 金额: $ 7.68万
• 依托单位: GUNMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08555182/
• 关键词: ELECTROSPRAY; ION REACTION; De-NOx PROCESS; ACID RAIN; FINE DROPLET; ABSORPTION; CORONA DISCHARGE; POLLUTION CONTROL; 無触媒脱硝法; 連鎖反応; 環境浄化技術

In this study, we proposed the novel De-NOx technologies by using the fine water droplets which produced by electrospray method. First one is the enhancement of thermal De-NOx reaction at low temperature by atomization of phenol and/or ammonia solution. We obtained the following results.(1) By coexisting ammonia with phenol aqueous solution, reduction of NO was proceeded at the range of lower temperature, 650-750ﾟC,but was restrained at the range of higher temperature, 750-850ﾟC.(2) By injecting phenol/ammonia aqueous solution as droplet by electrospray method, the markedly improvement of NO reduction was confirmed. About 30% of nitrogen monoxide was reduced at 650ﾟC (twice as much as the case of pre-vaporized solution), and about 50% at 700ﾟC in the following condition, NO 388ppm, O2 4%, NH_3400ppm, phenol 102ppm, H_2O6.4%, N_2 balance, residence time 1.5-1.8sec.(3) As a result of the measurement of CO,CO_2 in outlet gas, we could see more CO concentration at low temperature, 600-650ﾟC.So phenol seems to be decomposed by adding sprayd solutions.Second, the effects of the atomization of droplets into corona discharge reactor on the NOx reduction were examined and have obtained the following results.(1) The efficiency of NOx removal was improved via atomization of fine water droplets into the discharge plasma.(2) Decreasing the mean diameter of droplets, which were injected in the corona discharge, the De-NOx efficiency improved. Especially, we obtained the maximum De-NOx efficiency by using nebulizer.(3) The effect of pH on the De-NOx efficiency was investigated. The efficiency of De-NOx was improved both side of pH5.0.(4) NOx reduction was improved by the addition of H_2O_2. The amount of NO reduction was in the case of H_2O_2 was 1.5 times that of water droplets.(5) The necessary amount of water of this technology are less than that of conventional wet De-NOx process by a factor of about 1/100.

在这项研究中，我们提出了利用电喷雾方法产生的细小水滴来脱除NOx的新技术。第一种是通过雾化苯酚和/或氨溶液来强化低温下的热脱氮反应。结果表明：(1)氨和苯酚共存时，NO还原在较低温度(650-750ﾟC)范围内进行，而在较高温度(750-850ﾟC)范围内受抑制；(2)用电喷雾的方法将苯酚/氨水溶液作为液滴注入，可明显促进NO的还原。在650ppm，O2 4%，NH_3400ppm，苯酚102ppm，H_2O_6.4%，N_2平衡，停留时间1.5-1.8秒的条件下，在650ﾟC时，约30%的一氧化氮被还原(是预汽化溶液的两倍)，在700ﾟC时，约有50%的NO被还原。(3)通过测量出口气体中CO，CO_2的含量，我们可以看到在600-650ﾟC的低温下，CO浓度更高，所以苯酚似乎被喷雾溶液分解了。考察了电晕放电反应器中雾化液滴对NOx脱除效果的影响，得到了以下结果：(1)微细水滴雾化在放电等离子体中提高了NOx的脱除效率；(2)减小了注入电晕放电的液滴的平均直径，提高了脱氮效率。其中，雾化器的脱氮率最高。(3)考察了pH值对脱氮率的影响。加入H_2O_2可以提高NOx的脱除效率，H_2O_2的脱氮量是水滴的1.5倍。(5)该工艺所需用水量比传统湿法脱氮工艺少1/100左右。