流向变换-低温等离子体反应系统用于VOCs去除及热量分布研究

Removal of VOCs and heat distribution in a flow reversal plasma reaction system

将流向变换技术用于低温等离子体反应系统,考察了其对低温等离子体反应过程的影响,以放电参数(场强、频率)和系统运行参数(换向周期、接地极匝数、气体流速)为影响因素,探究了流向变换对低温等离子体系统温升(ΔT)和放电能量密度(SED)的影响,考察了该技术用于去除VOCs的情况。结果表明:在换向周期为8 min,场强为13.1 k V/cm,频率为150 Hz,接地极匝数为7匝,气体流速为14 cm/s条件下,ΔT最高可达187.3℃,SED最高可达284.4 J/L;等离子体放电区ΔT最高,出口处ΔT较低;蓄热段ΔT随流向变换发生周期性变化,其变化周期与反应系统的变换周期一致;将流向变换-低温等离子体反应系统应用于甲苯的去除,可以显著提升甲苯的降解率,在一定范围内,有利于提高系统的能量效率。

The reverse flow technology coupled with non-thermal plasma reaction system was used to investigate its effect on the process of non-thermal plasma reaction. Considering the influencing factors including discharge parameters（ e. g. electrical field intensity, frequency） and operating parameters（ e. g. cyclic period, grounding pole number, gas velocity）, the effects of reverse flow on temperature rise（ ΔT） and discharge energy density（ SED） of the system were investigated, and the application situation of the technology in removal of VOCs was analyzed. The results showed that the highest ΔT and SED were 187. 3 ℃ and 284. 4 J/L under the condition of cyclic period 8 min, field intensity 13. 1 k V/cm, frequency 150 Hz, grounding pole number 7 and gas velocity 14 cm/s. The ΔT of discharge area was the highest, while that of the outlet was the lowest in the system. The ΔT varied periodically with the cyclic period in the heat storage segment, whose change cycle was consistent with the period of reaction system. The degradation rate of toluene could be improved significantly by applying a flow reversal plasma reaction system, which was beneficial to improvement of the energy efficiency.