多级串联腐殖土固定床处理氨气硫化氢恶臭气体的机理

设计了腐殖土固定床串联缺氧SBR多级反应器对填埋场臭气与渗滤液进行协同处理，以气体表面负荷、水力负荷、污染物负荷为影响因素进行正交实验，探究腐殖土固定床对氨气与硫化氢的处理效能与去除机理，并运用物料衡算的方法对腐殖土固定床去除氨气的机理进行分析。结果表明：腐殖土固定床对氨气与硫化氢的平均去除率分别为95%与98%，各因素对氨气去除率的影响大小的依次顺序为气体表面负荷>污染物负荷>水力负荷，各因素对硫化氢去除率的影响大小的依次顺序为污染物负荷>气体表面负荷=水力负荷，最佳实验条件为气体表面负荷为7 m·h⁻¹，水力负荷为0.12 m·d⁻¹，氨气负荷为10 mg·(m³·h)⁻¹，硫化氢负荷为2 mg·(m³·h)⁻¹。机理分析的结果表明多级串联腐殖土固定床对氨气去除主要是靠气相与液相的分压差 (浓度差) ，传质受进口氨气浓度、即氨气气相分压影响，此过程中气膜阻力远大于液膜阻力，近似于气膜控制过程，且各级液相氨氮等效形成的分压差距较小、气相与液相的分压差 (浓度差) 与气液有效传质面积逐级减。本研究结果可为现有的填埋场臭气处理技术上发展腐殖土固定床协同处理臭气渗滤液工艺提供参考。

Mechanism study on the treatment of ammonia and hydrogen sulfide odor gas by multistage humus soil fixed beds

A humus soil fixed bed series anoxic SBR multistage reactor was designed to carry out collaborative treatment of odor and leachate in landfill. Orthogonal experiments were conducted with gas surface load, hydraulic load and pollutant load as influencing factors to explore the treatment efficiency and removal mechanism of ammonia and hydrogen sulfide by humus soil fixed bed. The mechanism of ammonia removal by humus soil fixed bed was analyzed by means of material balance. The results show that: The average removal rates of ammonia and hydrogen sulfide in humus fixed bed were 95% and 98%, respectively. The order of influence of each factor on ammonia removal rate was gas surface load > pollutant load > hydraulic load, and the order of influence of each factor on hydrogen sulfide removal rate was pollutant load > gas surface load = hydraulic load. The optimal experimental conditions are 7 m·h gas surface load, 0.12 m·d hydraulic load, 10 mg·(m 3·h)−1 ammonia load and 2 mg·(m3·h)−1 hydrogen sulfide load. The results of mechanism analysis show that the removal of ammonia by multistage humus soils fixed bed mainly depends on the partial pressure difference (concentration difference) between the gas phase and the liquid phase, and the mass transfer is affected by the concentration of imported ammonia, namely the partial pressure of ammonia gas phase. In this process, the resistance of gas film is much greater than that of liquid film, which is similar to the control process of gas film. Moreover, the partial pressure difference formed by the equivalent ammonia nitrogen at all levels in the liquid phase is small, and the partial pressure difference (concentration difference) between the gas phase and the liquid phase and the effective mass transfer area of the gas are gradually reduced.