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51.
用钢渣对含铬废水进行预处理,探讨了钢渣粒度、用量、废水pH值和添加硫酸亚铁还原剂的影响.结果表明,经硫酸亚铁还原处理后再用钢渣处理比单纯用钢渣处理的效果明显提高,采用钢渣/总铬质量比为40的100目钢渣处理经硫酸亚铁还原后的含铬废水,总铬和Cr6 去除率分别达79%和84%,采用钢渣柱进行的两级淋滤实验进一步表明该方法可作为工业上含铬废水处理的预处理段.处理后的废钢渣同工业铬渣一起进行水泥固化,标准养护20 d后固化体表面Cr6 浸出率、破碎至5 mm粒径以下和酸雨淋溶下的浸出液Cr6 浓度均符合安全标准,可作为普通建材或进行填埋处置. 相似文献
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Duan Zhong-Hua Quan Xiao-Long Qiao You-Ming Li Xiao-Qing Pei Hai-Kun He Gui-Fang 《Russian Journal of Ecology》2019,50(1):20-26
Russian Journal of Ecology - The present study was conducted to investigate the n-alkane composition of typical alpine meadows. Plant and soil samples were collected and analyzed to characterize... 相似文献
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模拟可见光下土壤表面石油的光化学降解研究 总被引:1,自引:0,他引:1
在模拟可见光照射下,分析了土壤中的初始含油量、土壤类型和土壤pH值对石油在土壤表面光降解过程的影响,并利用紫外-可见分光光度法(UV-Vis)、气相色谱-氢火焰离子化检测器(GC-FID)和傅立叶红外光谱(FTIR)等方法对石油在光降解过程中的演变规律进行研究.结果表明,石油在土壤表面上的光化学降解行为符合准一级反应动力学,实验测得石油的光解速率常数为0.002 6~0.017 2 h-1,半衰期为40~267 h.GC-FID分析结果表明,在光降解50 h后,石油的饱和烃组分中高碳数的烷烃相对含量降低,低碳数的烷烃相对含量提高;芳香烃组分的大部分色谱峰有明显地降低或消失.红外光谱分析发现,光照60 h后土壤萃取液中可能产生了羰基类化合物,说明石油在光降解过程中逐渐发生氧化. 相似文献
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The only joint effort area of provincial and municipal governments resides in Guangdong Province and Shenzhen City in China’s carbon emission trading system (ETS) pilots, which characterize the national carbon ETS plots. The present study on the operating experience from this area has important reference value for the national carbon ETS. Analysis and comparison of the key elements show many differences in coverage, total allowance, allowance allocation, and MRV mechanism between Guangdong and Shenzhen carbon ETS. The present study provides the following explanation: (1) the design characteristics of carbon ETS (e.g. coverage, total quotas, the allocation, and MRV mechanism) depend on the local geographical conditions and policy goals. The differences of economic structure in Guangdong Province and Shenzhen City result in different coverage, which then result in differences in other management elements. (2) The operating state of the carbon market is affected by overall design of carbon ETS: in the case of tighter total allowance, lower proportion of China Certified Emission Reductions, and harsher punishment, the carbon market is relatively active, which intends to produce carbon financial market. Based on deep analysis of operation characteristics of carbon ETS in Guangdong and Shenzhen, the present study suggests that (1) the allowance should be allocated freely at the beginning stage and then gradually transited to the voluntary paid auction; (2) the allowances assigned to companies shall be linked up with their energy-saving objectives; (3) the output fluctuations and economic influence on the allowance allocation should be properly handled to maintain the fairness and consistence of allowance allocation standards; (4) stable public expectation is one of the key elements to maintain the regular operation of carbon ETS; (5) constrained carbon emission behavior outside ETS can contribute to social justice; and (6) the improvement of professional skills of relevant personnel in the enterprise and independent third party can enhance carbon emissions data reliability. 相似文献
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Yuan-Na Xing Ying Guo Mei Xie Ru-Lang Shen 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1382-1387
A solid-phase microextration-based sampling method was employed to determine the concentrations of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (DDE) and 1-chloro-2,2-bis(p-chlorophenyl)ethene (DDMU), in two estuarine bays, Daya Bay and Hailing Bay, of South China. Six DDT components including p,p′-DDT, o,p′-DDD, p,p′-DDD, o,p′-DDE, p,p′-DDE, and p,p′-DDMU were detected in Hailing Bay, while only p,p′-DDD was found in Daya Bay. p,p′-DDD was the most abundant DDT component in both bays, sharply different from the previous finding in the water column of the Palos Verdes Shelf, California, USA that p,p′-DDE was prevalent. In addition, the occurrence of p,p′-DDMU (with a range of 0.047-0.21 ng/L in Hailing Bay) has not been reported around the globe, and its presence in our study region appeared to stem from dehydrochlorination of p,p′-DDD, favored under aerobic conditions, but further investigations are clearly needed to confirm the mechanism for generation of DDMU in estuarine environments. 相似文献
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Jun-Ji Cao Bai-Qing Xu Jian-Qiao He Xian-Qin Liu Yong-Ming Han Ge-hui Wang Chong-shu Zhu 《Atmospheric environment (Oxford, England : 1994)》2009,43(29):4444-4452
Carbonaceous aerosol concentrations were determined for total suspended particle samples collected from Muztagh Ata Mountain in western China from December 2003 to February 2006. Elemental carbon (EC) varied from 0.004 to 0.174 μg m?3 (average = 0.055 μg m?3) while organic carbon (OC) ranged from 0.12 to 2.17 μg m?3 and carbonate carbon (CC) from below detection to 3.57 μg m?3. Overall, EC was the least abundant fraction of carbonaceous species, and the EC concentrations approached those in some remote polar areas, possibly representing a regional background. Low EC and OC concentrations occurred in winter and spring while high CC in spring and summer was presumably due to dust from the Taklimakan desert, China. OC/EC ratios averaged 10.0, and strong correlations between OC and EC in spring–winter suggest their cycles are coupled, but lower correlations in summer–autumn suggest influences from biogenic OC emissions and secondary OC formation. Trajectory analyses indicate that air transported from outside of China brings ~0.05 μg m?3 EC, ~0.42 μg m?3 OC, and ~0.10 μg m?3 CC to the site, with higher levels coming from inside China. The observed EC was within the range of loadings estimated from a glacial ice core, and implications of EC-induced warming for regional climate and glacial ice dynamics are discussed. 相似文献