甲醇装置酸性尾气工业处理试验

进行了甲醇装置酸性尾气工业处理试验,用体积分数为25％～30％的N-甲基二乙醇胺(MDEA)水溶液提浓该酸性尾气,提浓后的酸性尾气送至克劳斯硫磺回收装置回收硫磺。在再生塔底温度为124℃、气液比为80、吸收塔塔板为11层的条件下脱除H2S,净化气中H2S体积分数小于0．25％,去除率为97．3％。该项目的实施消除了HCN、CH30H、H2S等有毒气体对大气环境的污染,同时可回收硫磺736t／a,具有较大的社会效益和一定的经济效益。     

Urinary phenols and parabens metabolites associated with cardiovascular disease among adults in the United States

Environmental Science and Pollution Research - The field of environmental health has begun to examine the effects of higher-order chemical combinations. The current literature lacks studies...     

嗜热栖热菌降解氟喹诺酮类抗生素

氟喹诺酮类抗生素在各种环境基质中积累造成的生态和耐药基因污染等问题已引起广泛的关注。为了能够有效去除环境中氟喹诺酮类抗生素污染并且探究其生物代谢途径,利用嗜热菌Thermus sp. C419在高温(70℃)条件下降解2种典型的氟喹诺酮类抗生素(诺氟沙星和恩诺沙星),分析了菌株C419对这2种药物在单一和混合添加时的降解特性;通过UPLC-MS/MS检测了其相关的降解产物,并推测了可能的代谢途径;利用平板扩散法对生物降解后的氟喹诺酮类药物进行抑菌活性测定。结果表明:氟喹诺酮类化合物可被菌株C419有效降解,降解率为60%～80%;该生物降解过程符合一级动力学模型,培养基中氟喹诺酮类化合物浓度越高,降解率越高,降解半衰期越短;菌株C419对诺氟沙星的生物降解有3条可能的降解途径和7种降解产物,对恩诺沙星的生物降解有4条可能的降解途径和6种降解产物。此外,与2种药物的母体化合物相比,生物降解后药物对不同细菌的抗菌活性均有一定程度的降低,这说明嗜热菌株C419在热环境中去除氟喹诺酮类污染物方面可能会具有良好的实用性和应用前景。     

Surfactant-enhanced biodegradation of crude oil by mixed bacterial consortium in contaminated soil

This study evaluated the effects of two surfactants (i.e., Tween 80 and SDS) on biodegradation of crude oil by mixed bacterial consortium in soil-aqueous system. The mixed bacterial consortium was domesticated from the activated sludge of cooking plant through a progressive domestication process. High-throughput sequencing analysis revealed that Rhodanobacter sp. was the dominant bacteria. The higher CMC_eff value for two surfactants was observed in soil-aqueous system compared with that in aqueous system, which was likely due to their adsorption onto soil particles. Either Tween 80 or SDS can be utilized as carbon source and promote the growth of mixed bacterial consortium. Further findings evidenced that the degradation of crude oil can be enhanced by adding either Tween 80 or SDS. The performance of Tween 80 was generally superior to SDS for the crude oil degradation. The highest crude oil degradation efficiency was 42.2 and 31.0% under the conditions of 5 CMC_eff of Tween 80 and 2 CMC_eff of SDS, respectively. Furthermore, the degradation efficiency of crude oil in remediation experiment (i.e., 77%) evidenced that the integration of adding Tween 80 and inoculating mixed bacterial consortium was effective for crude oil-contaminated soil decontamination.     

Leaching of Cu,Cd, Pb,and phosphorus and their availability in the phosphate-amended contaminated soils under simulated acid rain

Environmental Science and Pollution Research - Phosphate amendments have been used to immobilize heavy metal-contaminated soils. However, phosphate amendments contain large amounts of phosphorus,...     

Effects of biofilter media depth and moisture content on removal of gases from a swine barn

Media depth (MD) and moisture content (MC) are two important factors that greatly influence biofilter performance. The purpose of this study was to investigate the combined effect of MC and MD on removing ammonia (NH₃), hydrogen sulfide (H₂S), and nitrous oxide (N₂O) from swine barns. Biofiltration performance of different MDs and MCs in combination based on a mixed medium of wood chips and compost was monitored. A 3 × 3 factorial design was adopted, which included three levels of the two factors (MC: 45%, 55%, and 67% [wet basis]; MD: 0.17, 0.33, and 0.50 m). Results indicated that high MC and MD could improve NH₃ removal efficiency, but increase outlet N₂O concentration. When MC was 67%, the average NH₃ removal efficiency of three MDs (0.17, 0.33, and, 0.50 m) ranged from 77.4% to 78.7%; the range of average H₂S removal efficiency dropped from 68.1–90.0% (1–34 days of the test period) to 36.8–63.7% (35–58 days of the test period); and the average outlet N₂O concentration increased by 25.5–60.1%. When MC was 55%, the average removal efficiency of NH₃, H₂S, and N₂O for treatment with 0.33 m MD was 72.8 ± 5.9%, 70.9 ± 13.3%, and –18.9 ± 8.1%, respectively; and the average removal efficiency of NH₃, H₂S, and N₂O for treatment with 0.50 m MD was 77.7 ± 4.2%, 65.8 ± 13.7%, and –24.5 ±12.1%, respectively. When MC was 45%, the highest average NH₃ reduction efficiency among three MDs was 60.7% for 0.5 m MD, and the average N₂O removal efficiency for three MDs ranged from –18.8% to –12.7%. In addition, the pressure drop of 0.33 m MD was significantly lower than that of 0.50 m MD (p < 0.05). To obtain high mitigation of NH₃ and H₂S and avoid elevated emission of N₂O and large pressure drop, 0.33 m MD at 55% MC is recommended.

Implications: The performances of biofilters with three different media depths (0.17, 0.33, and 0.50 m) and three different media moisture contents (45%, 55%, and 67% [wet basis]) were compared to remove gases from a swine barn. Using wood chips and compost mixture as the biofilters media, the combination of 0.33 m media depth and 55% media moisture content is recommended to obtain good reduction of NH₃ and H₂S, and to simultaneously prevent elevated emission of N₂O and large pressure drop across the media.     

撞击流反应器萃取电镀废水中Cr6+的实验研究

以磷酸三丁酯（TBP）为萃取剂,用撞击流反应器对模拟含铬电镀废水中的Cr^6＋进行了萃取脱除实验研究。与相同条件下的传统单级化学萃取相比,撞击流反应器利用两喷嘴的射流作用在两流体相对撞击时获得高效传质区域,能有效强化液液萃取的相际传质过程,其单级萃取率最多可提高20．11％。当萃取剂中TBP的体积分数为10％、相比（有机相与水相的体积比）为1：2、萃取时间为1min、H^＋的浓度为1．0mol／L时,通过实验得出适宜的操作条件为：喷嘴间距离为喷嘴直径的3．4倍,搅拌转速600r／min,萃取温度30—40℃,在此条件下Cr^6＋的萃取率为31．5％。     

大气扩散模式预测计算软件的开发

结合Microsoft Visual Basic(VB)语言的编程特点,探讨了大气环境影响评价计算机软件系统的理论基础、设计思想和应用程序编制的实现方法,编制了专门处理大气扩散模式浓度计算的应用程序,避免了大量繁杂的手工计算工作,使计算快速、准确,提高了环境影响评价工作的质量.     

我国矿产资源的合理开发利用

我国是世界上矿产资源总量丰富、种类较齐全的国家之一。由于人口众多,矿产资源人均占有量不到世界人均占有量的1/2。作者根据中国的矿情提出立足国内,合理利用国内、国外两种资源;增产与节约并重,提高矿产品深加工,加强综合利用,重视二次资源的回收,增加地勘投资,加强地勘工作。     

UNITANK工艺提高氮、磷去除率的研究

采用UNITANK工艺处理城市生活污水 ,考察了主体阶段和过渡阶段时间的设置对除磷脱氮处理效果的影响 ,并提出通过氧化还原电位进行释磷和反硝化监控的设想