沉降除藻协同沉积物覆盖对藻华水体甲烷释放的影响

本研究以藻华水体甲烷释放为对象,利用模拟柱培养实验,探究了沉降除藻和沉积物覆盖复合技术对富营养化甲烷释放的影响.结果表明,沉降除藻结合沉积物覆盖处理可有效改善水环境,实现对甲烷释放的控制,但不同覆盖材料的效果存在差异;活性炭效果要优于土壤和沸石.相比于对照体系水体溶解氧(DO)2. 5 mg·L-1和氧化还原电位(ORP)100 m V,沉积物界面ORP -125 m V,沉降除藻协同活性炭覆盖体系中水体DO和ORP分别升高至3. 1 mg·L-1和174 m V,沉积物界面ORP逆转为168 m V,实验期间甲烷释放量相对于对照组减少90. 2%.研究结果在富营养水体甲烷减排方面具有指导性意义.

Synergy of Algal Sedimentation and Sediment Capping for Methane Emission Control in Bloom Waters

This study tested a strategy in simulated column systems to control methane emissions from algal bloom waters using the combined technology of algae sedimentation and sediment capping. The results demonstrated that the synergy of algal sedimentation and sediment capping can effectively improve the water environment and reduce methane emissions; however, the improvement rate differed among capping materials. The use of activated carbon yielded better performance on the water environment improvement and methane emission control than soil and zeolite. Compared with the control system, the dissolved oxygen and redox potential in the water were increased from<2.5 mg·L^-1 to 3.1 mg·L^-1 and from<100 mV to 174 mV, respectively. In addition, the redox potential in the surface sediment was reversed from -125 mV to 168 mV after algal sedimentation with subsequent activated carbon capping. As a result, methane emissions in the algal sedimentation-activated carbon capping systems were decreased by 90.2% over the incubation period relative to the control system. This study provides useful insights into methane emission control in eutrophic waters.