Mercury removal from flue gas using nitrate as an electron acceptor in a membrane biofilm reactor

Membrane bioreactor achieved mercury removal using nitrate as an electron acceptor. The biological mercury oxidation increased with the increase of oxygen concentration. Ferrous sulfide could make both Hg²⁺ and MeHg transform into HgS-like substances. Nitrate drives mercury oxidation through katE, katG, nar, nir, nor, and nos. Mercury (Hg⁰) is a hazardous air pollutant for its toxicity, and bioaccumulation. This study reported that membrane biofilm reactor achieved mercury removal from flue gas using nitrate as the electron acceptor. Hg⁰ removal efficiency was up to 88.7% in 280 days of operation. Oxygen content in flue gas affected mercury redox reactions, mercury biooxidation and microbial methylation. The biological mercury oxidation increased with the increase of oxygen concentration (2%‒17%), methylation of mercury reduced with the increase of oxygen concentration. The dominant bacteria at oxygen concentration of 2%, 6%, 17%, 21% were Halomonas, Anaerobacillus, Halomonas and Pseudomonas, respectively. The addition of ferrous sulfide could immobilize Hg²⁺ effectively, and make both Hg²⁺ and MeHg transform into HgS-like substances, which could achieve the inhibition effect of methylation, and promote conversion of mercury. The dominant bacteria changed from Halomonas to Planctopirus after FeS addition. Nitrate drives mercury oxidation through katE, katG, nar, nir, nor, and nos for Hg⁰ removal in flue gas.     

The positive role of trade openness in industrial green total factor productivity—provincial evidence from China

Environmental Science and Pollution Research - The sustainable development of the economy is a key issue of global concern. Green total factor productivity (GTFP) combining economic growth with...     

Source apportionment of bioavailable trace metals in soil based on chemical fractionation and its environmental implications

Environmental Science and Pollution Research - The bioavailable trace metals are closely related to environmental safety and human health, which might have different source characteristics from the...     

基于不同时间尺度综合指数贡献率的攀枝花市大气污染特征分析

选取2016—2022年攀枝花市环境空气质量监测数据，基于年度、季度、月度、小时时间尺度评价环境空气质量综合指数贡献率。结果表明，攀枝花市污染类型已由传统的单一工业型污染转变为复合型污染，且污染物在不同时间尺度下的分布特征明显。从季度尺度来看，第一季度细颗粒物(PM_2.5)综合指数贡献率较大，第二和第三季度臭氧(O₃)综合指数贡献率较大，第四季度二氧化氮(NO₂)及PM_2.5综合指数贡献率较大。从月度尺度来看，O₃在3—8月的贡献较大，PM_2.5、NO₂、可吸入颗粒物(PM₁₀)、一氧化碳(CO)、二氧化硫(SO₂)在1—2月及11—12月的贡献较大。从小时尺度来看，O₃在13—19点贡献较大，PM₁₀、PM_2.5、CO在8—13点贡献较大，SO₂在9—13点贡献较大，NO₂在8—1...     

中国生态环境质量与经济协同发展研究

经济发展与生态环境保护相协调、双赢是生态文明建设的核心，也是生态文明的基本特征。本研究使用生态质量、环境质量以及经济发展指标构建协同发展指数，评估我国337个地级及以上城市2017年的生态环境质量与经济发展的协同度，按照评估结果将337个城市分为协同增长、金色污染、绿色贫困和拮抗发展4种类型。评估结果显示，2017年中国经济发展指数优于生态环境质量。其中，金色污染类型城市数量最多（122个，占总面积的21.89%）；绿色贫困类型城市面积占比最大（76个，占总面积的32.86%）；拮抗发展类型城市65个，占总面积的30.26%；协同增长类型城市74个，占总面积的14.99%。通过量化生态环境质量与经济发展的协同程度，以期为生态文明建设和“绿水青山就是金山银山”理念实践提供科学理论支撑。     

Lessons from farmers’ adaptive practices to climate change in China: a systematic literature review

Environmental Science and Pollution Research - Due to the vulnerability and exposure of agriculture, farmers’ adaptive strategies to climate change are important to food security and...