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961.
采用Fenton法氧化-微电解-厌氧序批式反应(ASBR)-好氧序批式反应(SBR)的工艺流程,处理高浓度硝基苯类生产废水进行试验研究。结果表明,进水硝基苯浓度1300mg/L,COD浓度12480mg/L,pH为2.8时,投加H2O2量为3.3g/L,Fe2+为560mg/L,反应时间为90min,沉淀后上清液进行微电解反应60min并调节pH=8.0,沉淀后再进入ASBR反应器和SBR反应器,硝基苯去除率可达99.4%,COD去除率达94.4%。  相似文献   
962.
磨盘山水库水质富营养化的防治对策研究   总被引:1,自引:0,他引:1  
磨盘山水库是哈尔滨市人民重要的饮用水源地。从库区面源污染来源、农业各类面源污染入库量比较、磨盘山水库水质富营养化状况及趋势等方面论述了磨盘山水库水质富营养化防治对策。提出要加强磨盘山水库水质的科学研究,防止水库水质的富营养化发生。  相似文献   
963.
矿产资源规划环境影响评价指标体系及方法的探讨   总被引:2,自引:0,他引:2  
为了减少矿产资源开发过程中对环境造成的影响,从源头上控制污染,最有效的方法之一就是对矿产资源规划进行环境影响评论.结合中国矿产资源规划的情况,从矿产资源的特点出发,提出了以自然地理环境、地貌环境、大气环境、水环境、生态环境和社会经济环境等六类环境影响组成作为评价因子,并探讨了可适用于矿产资源规划环境影响评价的方法:环境成本-效益分析法,基于可持续发展能力的评价方法.这为矿产资源规划环境影响评价提供了借鉴.  相似文献   
964.
储油罐防腐涂料选用及施工   总被引:1,自引:0,他引:1  
储油罐内壁选用导静电涂料,油罐外壁涂料需要较长的防腐年限,所以应选用防锈性好的底漆、面漆.施工过程中应按照规定严格执行涂料施工方法,并经检测达到合格要求,才能保证质量和安全.  相似文献   
965.
针对中型针织面料印染厂含有机污染物浓度较高的废水,设计了一套废水处理工艺流程,并通过实例对其进行了检验。废水水质CODcr为1 200 mg/L、BOD5为400 mg/L、SS为280 mg/L、色度为400倍、处理水量1 000 m^3/d,在经过水解、生物接触氧化和沉淀等工艺处理后,出水指标稳定,并且达到了环保部门的排放要求。  相似文献   
966.
967.
The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.  相似文献   
968.
Luoyang is a typical heavy industrial city in China, with a coal-dominated energy structure and serious air pollution. Following the implementation of the clean air actions, the physicochemical characteristics and sources of PM2.5 have changed. A comprehensive study of PM2.5 was conducted from October 16, 2019 to January 23, 2020 to evaluate the effectiveness of previous control measures and further to provide theory basis for more effective policies in the future. Results showed that the aerosol pollution in Luoyang in autumn and winter is still serious with the average concentration of 91.1 μg/m3, although a large reduction (46.9%) since 2014. With the contribution of nitrate increased from 12.5% to 25.1% and sulfate decreased from 16.7% to 11.2%, aerosol pollution has changed from sulfate-dominate to nitrate-dominate. High NO3/SO42− ratio and the increasing of NO3/SO42− ratio with the aggravation of pollution indicating vehicle exhaust playing an increasingly important role in PM2.5 pollution in Luoyang, especially in the haze processes. Secondary inorganic ions contributed significantly to the enhancement of PM2.5 during the pollution period. The high value of Cl/Na+ and EC concentration indicate coal combustion in Luoyang is still serious. The top three contributor sources were secondary inorganic aerosols (33.3%), coal combustion (13.6%), and industrial emissions (13.4%). Close-range transport from the western and northeastern directions were more important factors in air pollution in Luoyang during the sampling period. It is necessary to strengthen the control of coal combustion and reduce vehicle emissions in future policies.  相似文献   
969.
Dissolved organic nitrogen(DON)extracted from Lake Shankou sediments using KCl was isolated into hydrophobic and hydrophilic fractions.The bioavailabilities of the hydrophobic and hydrophilic fractions to three types of bacterial communities collected from sediments,activated sludge and compost products were examined.The DON recoveries obtained by DAX-8 and cation exchange resins treatment were 96.17% ± 1.58% and 98.14% ±0% for the samples obtained from N4 and N14 stations,respectively.After 25 days of incubation at 25°C,most DON(59% to 96%)was degraded.Hydrophilic DON exhibited a higher reduction rate than hydrophobic DON during the growth phase.Untreated wastewater from Changshuihe town was the main degradable DON source to station N4,and 93% of hydrophilic DON and 80% of hydrophobic DON were degraded.Station N14 received a large amount of refractory DON from forest soils and exhibited DON degradation rates of 82% and 71% for the hydrophilic and hydrophobic fractions,respectively.Amino acid contents and fluorescence intensities were also analyzed.Approximately 27% to 74% of amino acids were taken up by day 5,and their concentration gradually increased in the following days due to the decomposition of dissolved proteins.Parallel factor analysis resulted in identification of tryptophan-like proteins,tyrosine-like proteins and FA-like substances.During the growth phase,40%–51% of the tryptophan-like proteins were taken up by bacteria,and the accumulation of tyrosine-like proteins was attributed to the release of biotic substances.The concentration of the FA-like substances decreased due to microbial decomposition.  相似文献   
970.
A mesophilic,Gram-negative,arsenite[As(Ⅲ)]-oxidizing and arsenate[As(V)]-reducing bacterial strain,Pseudomonas sp.HN-2,was isolated from an As-contaminated soil.Phylogenetic analysis based on 16 S r RNA gene sequencing indicated that the strain was closely related to Pseudomonas stutzeri.Under aerobic conditions,this strain oxidized 92.0%(61.4 μmol/L) of arsenite to arsenate within 3 hr of incubation.Reduction of As(V) to As(Ⅲ) occurred in anoxic conditions.Pseudomonas sp.HN-2 is among the first soil bacteria shown to be capable of both aerobic As(Ⅲ) oxidation and anoxic As(V) reduction.The strain,as an efficient As(Ⅲ) oxidizer and As(V) reducer in Pseudomonas,has the potential to impact arsenic mobility in both anoxic and aerobic environments,and has potential application in As remediation processes.  相似文献   
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