Development of High Efficiency Gas Treatment System by Pulsed Electron Beam Irradiation

本研究计划旨在发展一套有效的气体处理系统，以减少包括挥发性有机化合物（VOCs）在内的气体化合物的排放。采用线离子等离子体源（WIPS）的低能二次发射电子枪（SEEG）产生电子束。为了达到提高SEEG对VOCs去除效率的主要目的，对离子束和二次电子束的特性进行了研究。离子束电流测量结果表明，电子加速室存在一定的局限性，因此可以将wps压力优化为20 mTorr。利用光敏膜测量了气体处理室中电子束能量的分布，观察到电子束在63kv时通过电子窗滤入，在100kv加速电压下能量损失较小。在100 kV时，电子束到达距离电子窗80mm的高度，并在（27x373x60） mm3的尺寸上进行足够的能量分布。在加速电压为100 kV、气体体积为6 l的条件下，对苯和三氯乙烯的分解进行了研究，在1000次枪数下，苯的分解率为60%，三氯乙烯的分解率为70%。结果表明，在3 L/s的流速下，脉冲重复频率为2 kHz，苯的分解率可达90%，SEEG是小型工业企业或吸烟区处理VOCs的理想装置。

The purpose of this research project is to develop an effective gaseous treatment system in order to reduce the emission of gaseous compounds including Volatile Organic Compounds (VOCs).A low-energy secondary emission electron gun (SEEG) using wire ion plasma source (WIPS) was applied to generate electron beams. The characteristics of ion beam and secondary electron beam were investigated in order to achieve main objective, which is to increase removal efficiency of VOCs using SEEG. The results of ion beam current measurement showed that there were some limitations at electron accelerating chamber, so the pressure at WIPS can be optimized for 20 mTorr. Distribution of electron beam energy at gas treatment chamber was measured using photosensitive film and it was observed that electron beam filtered in through the electron window at 63 kV and there expected to be small energy losses at the accelerating voltage of 100 kV. At 100 kV, the electron beam reaches the distance as high as 80 mm from electron window and performs enough energy distribution at the dimension of (27x373x60) mm3.Decomposition of benzene and trichloroethylene were studied at the accelerating voltage of 100 kV, the gas volume of 6 L. The degrees of decomposition at the shot number of 1000 were observed as 60 % for benzene and 70 % for trichloroethylene, respectively. The results show that 90 % decomposition of benzene at a flow rate of 3 L/s can be achieved at pulse repetition rate of 2 kHz and SEEG is a promising device for treating VOCs at a small-scale industrial corporation or a smoking area.