High concentration NOx, SOx and particulate removal system using the plasma-chemical hybrid process

研究的目的是在高烟气温度（>250℃）下去除高浓度（1000 ~ 2000 ppm） NOx和SOx，并去除柴油机和锅炉排放的颗粒物（PM）。采用吸附和等离子体混合工艺控制柴油排放，采用等离子体化学混合工艺控制锅炉排放。在柴油排放控制干法过程中，利用分子筛型吸附剂（MS-13X）对NOx进行有效吸附，吸附后的NOx在柴油排放系统中通过氮气的加热解吸再生。脱附后的高浓度NOx被非热等离子体完全还原为N_2和O_2。针对氮氧化物吸附过程对柴油机含水率的影响，对硅酸盐的使用进行了研究。结果表明，在吸附剂的上游使用硅酸盐。（或高温侧）。其他疏水吸附剂，如Mn基和More orbent也被发现非常适合于NOx的吸附。我们还发现，即使在120℃下，NOx的热脱附也能有效地进行，并且随着重复热脱附过程的进行，NOx的浓度不断增加，并且在重复脱附7次之后，NOx的脱附效率保持不变。对于PM，采用常规柴油微粒过滤器（DPF）捕集PM，在250℃的气体温度下用NO_2和O_3分别焚烧。即使是在室温下。另一方面，等离子体化学工艺用于锅炉排放控制，利用臭氧发生器在气流中氧化NO生成NO_2，生成的NO_2经化学洗涤器用Na_2SO_3溶液还原得到N_2和水溶性无毒Na_2SO_4。所需的O_3量约为气流中NO浓度的一个化学计量量。烟气中CO_2和O_2浓度对NOx的还原率有影响，并进行了优化研究，结果表明，在整个实验过程中，NOx的还原率达到85%以上。少

The objective of the research is to remove high concentration (1,000〜2,000ppm) NOx and SOx at high flue gas gas temperature (>250℃), and also to remove particulate matters (PM) from diesel engine and boiler emission. The adsorption and plasma hybrid process were employed to control the diesel emission and the plasma chemical hybrid process was employed to control the boiler emission. In the dry process for diesel emission control, the adsorbent using molecular shieve (MS-13X) was used to adsorb NOx effectively, and adsorbed NOx were desorbed and regenerated using N2 by means of heat in the diesel emission system. The desorbed high concentrated NOx were totally reduced by the nonthermal plasma to form N_2 and O_2. Since the moisture content in the diesel engine was affected by NOx adsorption process, the use of silicate was investigated. As the results, the use of silicate was to place upstream of the adsorbent.(or high temperature side). Other hydrophobic adsorbent such as Mn based ads … More orbent was also found to be extremely suited for NOx adsorption. We also found that NOx desorption by heat took place effectively even at 120℃ and NOx concentration was increased with repetitive thermal desorption and reached a constant desorption efficiency beyond 7 repetitive desorption process. As far as PM is concerned, PM was trapped with the conventional diesel particulate filter (DPF) and incinerated with either NO_2 at the gas temperature of 250℃ and O_3.even at the room temperature.On the other hand, the plasma chemical process used for boiler emission control, ozpnizer was used to oxidize NO to form NO_2 in the gas stream and formed NO_2 was reduced by the chemical scrubber using Na_2SO_3 solution to achieve N_2 and water soluble and nontoxic Na_2SO_4. The required amount of O_3 was approximately one stoichiometric of NO concentration in the gas stream. The NOx reduction was affected by CO_2 and O_2 concentrations in the gas stream and the optimization study was performed, resulting that more that 85% of NOx reduction was achieved throughout the experiments. Less