以液体硅胶与聚苯乙烯塑料泡沫小球为主体的掩蔽剂对污水暂存空间中恶臭气体的控制

Control of malodorous gases in the temporary storage space of sewage by the masking agent of liquid silicone and polystyrene plastic foam beads

为控制污水暂存空间产生的恶臭气体对周围环境造成的不利影响,在污水表面覆盖以液体硅胶(LSR)与聚苯乙烯塑料泡沫小球(EPS)为主体的掩蔽剂,通过增加污水中H2S向气相扩散的传质阻力来控制恶臭气体从污水中的释放。分别探究了掩蔽剂的成分组成、配比和平铺厚度对掩蔽效果的影响,以及掩蔽剂对下部水体水质的影响。结果表明:以LSR+EPS为载体的掩蔽剂可以阻断H2S的释放,其中以半透明LSR+EPS为载体的掩蔽剂效果最好;当半透明LSR与EPS载体的质量比为15~40,平铺厚度为0.1~0.5 cm时,其使用效果最好;掩蔽剂下部水体硫化物的浓度随污水停留时间的增加而增大;若利用SRB产物(高浓度H2S)抑制微生物,尚需较长时间达到毒性阈值。该掩蔽剂增加了H2S的传质阻力,有助于控制恶臭气体释放对所处环境的危害。

In order to control the adverse effect on the surrounding environment and people from the malodorous gas generated in the temporary storage space of sewage, a masking agent mainly composed of liquid silicone(LSR) and polystyrene plastic foam beads(EPS) was used to cover the surface of the sewage. This could increase the mass transfer resistance of H2S in sewage to the gas phase and control the release of malodorous gas from sewage. In this study, the effects of the composition of the masking agent, the requirements for the ratio and the thickness of the layup, as well as the effect on the water quality of the lower water body, were determined. The results showed that a masking agent with the LSR + EPS carrier could prevent H2S release, and the best effect occurred for the masking agent with translucent LSR + EPS carrier.When the mass ratio of translucent LSR and EPS carriers was 15~40, the tiling thickness was 0.1~0.5 cm, the best prevention effect was observed. The concentration of sulfide in the lower part of waterbody below the masking agent increased with the extension of residence time of the sewage. It will take a long time to reach the toxicity threshold if the SRB product(high H2S concentration) was used to inhibit the microbes. The masking agent increases the mass transfer resistance of H2 S and helps to control the harm to the environment caused by the release of malodorous gases.