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1.
根据谷里镇提供的水质监测资料、处理要求及现有地形条件,选用A2/O+曝气生物滤池作为该镇污水处理工程的核心处理工艺。该镇污水处理工程的设计规模为5 000 m3/d,污水处理工程的进水水质为pH:6~9 mg/L、CODCr:300 mg/L、BOD5:150 mg/L、氨氮:30 mg/L、TN:35 mg/L、TP:3 mg/L、SS:150 mg/L、动植物油:15 mg/L,经采用A2/O+曝气生物滤池作为该镇污水处理工程的核心处理工艺治理后,预计出水可以达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级A标准。 相似文献
2.
西渡造纸厂综合工业废水18000m^3/d,废水中含有纤维、木质素、半纤维素、草屑、泥灰、炉灰和纸浆短纤维等固溶物和微量的可溶性有机物以及碱等,同时含有大量的不溶性有机物;水呈黑色,属难生化的高浓度有机废水。在污水处理工程设计中通过对造纸黑液采用水解酸化-UBF-混凝沉淀联合处理工艺,出水可达到《造纸工业水污染物排放标准》(GWPB2-1999)要求。 相似文献
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拼装式反应器是一种采用栓接方式将经过防腐处理的钢板现场拼接的新型的污水处理设备。反应器的设计由反应器罐体结构设计、基础设计及配套产品的嵌接设计3个方面构成;拼装式反应器与成熟的污水处理技术(如UASB、水解工艺、SBR、BAF等)的结合提高了污水处理设备的技术含量。拼装式反应器已在猪场废水、食品加工废水、制药废水、啤酒废水及城市污水等废水处理工程中得到了成功应用。 相似文献
4.
本研究旨在为白洋淀淀中村生活污水处理技术选择提供一个优化决策方法。在对国内外农村生活污水处理技术深入调研的基础上,采用二级模糊综合评价法,对14项预选处理技术进行综合评估。首先从处理效果、技术性能以及经济性能三方面对各处理技术进行初级量化评估,再根据其评估数据对各项技术进行二级评估,最后结合淀中村自身特点筛选出较好的生活污水处理技术,探讨最适合白洋淀淀中村生活污水处理的优化方案。纯水村人口相对集中地区可采用人工湿地和水解酸化+人工湿地技术,人口相对分散地区可采用沼气净化技术;半水村人口相对集中地区可采用厌氧滤池+土壤渗滤和人工湿地+氧化塘技术,人口相对分散地区可采用沼气净化技术和土壤渗滤技术。 相似文献
5.
分层填料地下渗滤系统处理农村分散生活污水 总被引:1,自引:0,他引:1
为了解决农村生活污水直接排放造成的地表水以及地下水污染问题,本研究采用2种混合填料(5%粉煤灰+95%土壤和5%腐熟干牛粪+95%土壤)分层装填的3种不同结构的地下渗滤系统进行农村分散生活污水处理。结果表明,系统对污水中各主要污染因子都有较好的去除作用,且能承受一定的污染负荷波动;除总氮外,系统出水各项指标最低满足《地表水环境质量标准》中Ⅲ类标准,出水外排不会造成地表水污染;添加腐熟牛粪大大提高了系统总氮、硝氮的去除效率,出水稳定后满足地下水环境质量Ⅲ类标准。在应用过程中,建议选择2种填料填充高度各半的填充模式,以便各项指标均能达到最优处理效果。 相似文献
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污水处理设施已经成为中国区域环境质量改善的主要手段,通过对污水处理设施信息的收集整理、分析研究,明晰了中国污水处理设施的基本现状,分析了可能存在的问题并提出了相应的对策和措施,为中国城市污水处理相关研究提供基础和借鉴。截至2013年底,我国共建成各类污水处理设施6 124处,总设计处理能力1.66亿t/d,处理污水451.6亿t。已建成的污水处理设施规模以低于2万t/d为主,平均负荷率为74.4%。现有污水处理设施存在管网配套不合理、进水浓度偏低、负荷率普遍不足、执行排放标准偏低等问题。应从污水处理设施所在区域特点出发,因地制宜地选择合适的主体工艺类型和设计规模,科学配置相关管网设施,有效提高设施利用率。 相似文献
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活性污泥法处理味精厂废水的工艺优化 总被引:1,自引:0,他引:1
经过总结与改进武汉味全食品有限公司近5年污水处理工艺、设备,结果表明,经过增加三级曝气池、罗茨鼓风机等工艺改进,SS由132mg/L降为112mg/L;NH3-N由119mg/L降为37.6mg/L;Ar-OH由0.01mg/L降为0.009mg/L;BOD5由5年前的34.6mg/L降为现在的21.2mg/L;COD由5年前的117mg/L降为现在的62.6mg/L;运行成本由850万降到450万,通过此工艺的改进及优化,基本达到国家污水排放标准,完全达到行业排放标准。 相似文献
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P.R. Fresquez D.H. Kraig M.A. Mullen L. Naranjo Jr. 《Journal of environmental science and health. Part. B》2013,48(5):885-899
Abstract The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for 3H, 90Sr, 137Cs, totU, 238Pu, 239,240Pu, and 241Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of 90Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g‐1 [126E‐02 Bq kg‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g‐1 [518E‐02 Bq kg‐1]). The differences in 90Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y‐1 (1.0 ± 1.0 μSv y‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y‐1 (1000 μSv y‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations. 相似文献
12.
P.R. Fresquez J.R. Biggs K.D. Bennett D.H. Kraig M.A. Mullen J.K. Ferenbaugh 《Journal of environmental science and health. Part. B》2013,48(5):901-915
Abstract This paper summarizes radionuclide concentrations (3H, 90Sr, 137Cs, 238Pu, 239,240Pu, 241Am, and totU) in muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p<0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected from BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% on LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 lbs of muscle and 13 lbs of bone) were as follows: deer muscle = 0.22 mrem y‐1 (2.2 μSv y‐1), deer bone = 3.8 mrem y‐1 (38 μSv y‐1), elk muscle = 0.12 mrem y‐1 (1.2 μSv y‐1), and elk bone = 1.7 mrem y‐1 (17 μSv y‐1). All CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y‐1 (1000 μSv y‐1), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E‐06, which is far below the Environmental Protection Agency upper level guideline of 1E‐04. 相似文献
13.
Eucarlos L. Martins Oscarlina L.S. Weber Eliana F.G.C. Dores Cláudio A. Spadotto 《Journal of environmental science and health. Part. B》2013,48(8):877-882
This study aimed to evaluate the leaching of pesticides and the applicability of the Attenuation Factor (AF) Model to predict their leaching. The leaching of carbofuran, carbendazim, diuron, metolachlor, α and β endosulfan and chlorpyrifos was studied in an Oxisol using a field experiment lysimeter located in Dom Aquino – Mato Grosso. The samples of percolated water were collected by rain event and analyzed. Chemical and physical soil attributes were determined before pesticide application to the plots. The results showed that carbofuran was the pesticide that presented a higher leaching rate in the studied soil, so was the one representing the highest contamination potential. From the total carbofuran applied in the soil surface, around 6 % leached below 50 cm. The other pesticides showed lower mobility in the studied soil. The calculated values to AF were 7.06E-12 (carbendazim), 5.08E-03 (carbofuran), 3.12E-17 (diuron), 6.66E-345 (α-endosulfan), 1.47E-162 (β-endosulfan), 1.50E-06 (metolachlor), 3.51E-155 (chlorpyrifos). AF Model was useful to classify the pesticides' potential for contamination; however, that model underestimated pesticide leaching. 相似文献
14.
Endosulfan in China 2—emissions and residues 总被引:4,自引:0,他引:4
Hongliang Jia Yeqing Sun Yi-Fan Li Chongguo Tian Degao Wang Meng Yang Yongshen Ding Jianmin Ma 《Environmental science and pollution research international》2009,16(3):302-311
Background, aim, and scope Endosulfan is one of the organochlorine pesticides (OCPs) and also a candidate to be included in a group of new persistent
organic pollutants (UNEP 2007). The first national endosulfan usage inventories in China with 1/4° longitude by 1/6° latitude resolution has been reported
in an accompanying paper. In the second part of the paper, we compiled the gridded historical emissions and soil residues
of endosulfan in China from the usage inventories. Based on the residue/emission data, gridded concentrations of endosulfan
in Chinese soil and air have been calculated. These inventories will provide valuable data for the further study of endosulfan.
Methods Emission and residue of endosulfan were calculated from endosulfan usage by using a simplified gridded pesticide emission
and residue model—SGPERM, which is an integrated modeling system combining mathematical model, database management system,
and geographic information system. By using the emission and residue inventories, annual air and soil concentrations of endosulfan
in each cell were determined.
Results and discussion Historical gridded emission and residue inventories of α- and β-endosulfan in agricultural soil in China with 1/4° longitude
by 1/6° latitude resolution have been created. Total emissions were around 10,800 t, with α-endosulfan at 7,400 t and β-endosulfan
at 3,400 t from 1994 to 2004. The highest residues were 140 t for α-endosulfan and 390 t for β-endosulfan, and the lowest
residues were 0.7 t for α-endosulfan and 170 t for β-endosulfan in 2004 in Chinese agricultural soil where endosulfan was
applied. Based on the emission and residue inventories, concentrations of α- and β-endosulfan in Chinese air and agricultural
surface soil were also calculated for each grid cell. We have estimated annual averaged air concentrations and the annual
minimum and maximum soil concentrations across China. The real concentrations will be different from season to season. Although
our model does not consider the transport of the insecticide in the atmosphere, which could be very important in some areas
during some special time, the estimated concentrations of endosulfan in Chinese air and soil derived from the endosulfan emission
and residue inventories are in general consistent with the published monitoring data.
Conclusions To our knowledge, this work is the first inventory of this kind for endosulfan published on a national scale. Concentrations
of the chemical in Chinese air and agricultural surface soil were calculated for each grid cell. Results show that the estimated
concentrations of endosulfan in Chinese air and soil agree reasonably well with the monitoring data in general.
Recommendations and perspectives The gridded endosulfan emission/residue inventories and also the air and soil concentration inventories created in this study
will be updated upon availability of new information, including usage and monitoring data. The establishment of these inventories
for the OCP is important for both scientific communities and policy makers. 相似文献
15.
Denisha Gounden Kimona Kisten Roshila Moodley Shakira Shaik 《Journal of environmental science and health. Part. B》2016,51(1):1-7
This study is aimed at investigating the impact of water quality on the uptake and distribution of three non-essential and toxic elements, namely, As, Cd and Pb in the watercress plant to assess for metal toxicity. The plant was hydroponically cultivated under greenhouse conditions, with the growth medium being spiked with varying concentrations of As, Cd and Pb. Plants that were harvested weekly for elemental analysis showed physiological and morphological symptoms of toxicity on exposure to high concentrations of Cd and Pb. Plants exposed to high concentrations of As did not survive and the threshold for As uptake in watercress was established at 5 ppm. Translocation factors were low in all cases as the toxic elements accumulated more in the roots of the plant than the edible leaves. The impact of Zn on the uptake of toxic elements was also evaluated and Zn was found to have an antagonistic effect on uptake of both Cd and Pb with no notable effect on uptake of As. The findings indicate that phytotoxicity or death of the watercress plant would prevent it from being a route of human exposure to high concentrations of As, Cd and Pb in the environment. 相似文献
16.
Kurunthachalam Senthilkumar Carolyn A. Duda Daniel L. Villeneuve Kurunthachalam Kannan Jerzy Falandysz John P. Giesy 《Environmental science and pollution research international》1999,6(4):200-206
Concentrations of mono- (MBT), di- (DBT), and tri-(TBT) butyltin compounds were measured in eggs, liver, and muscle of nine
species of fish from four regions of the Baltic Sea - the Firth of Vistula, the Gulf of Gdańsk, Puck Bay, and the mouth of
the Vistula River. The overall concentration ranges among all the fish sampled from the four sites were: < 7 to 79 ng/g for
MBT, 6 to 1100 ng/g for DBT, 7 to 3600 ng/g for TBT, and 16 to 4800 ng/g for total BTs, on a wet wt basis. The highest concentration
of total BTs was found in herring liver from the Firth of Vistula (4800 ng/g, wet wt) and in roach muscle from Puck Bay (3300
ng/g, wet wt), while the least concentration was found in burbot eggs and liver from the Vistula River (39 and 32 ng/g, wet
wt, respectively). TBT was the major form of BTs present in most samples analyzed. Sediment samples collected from shipyards
in the Gulf of Gdańsk contained butyltin concentrations ranging from 1.2 to 46 μg/g (dry wt) for MBT, 2.0 to 42 μg/g for DBT,
and 2.6 to 40 μg/g for TBT. As with the fish, the majority of the BTs in sediment were present as TBT, which suggested recent
exposure of the aquatic environment of the region to TBT. 相似文献
17.
Chayya Roy Kundu Shubhadeep Roychoudhury 《Journal of environmental science and health. Part. B》2013,48(7):673-680
The effect of malathion [diethyl(dimethoxythiophosphorylthio)succinate] at sublethal concentration (0.006 ppm) on hematological parameters of the cricket frog (Fejervarya limnocharis) was studied for 24 hrs to 240 hrs of exposure and remarkable hematological alterations were observed. The study on hematological parameters revealed a highly significant decrease (P < 0.01) in the total erythrocytes count in malathion-exposed animals from 24 hours to 96 hrs of exposure as compared to control. Significant decreases (P < 0.01) of hemoglobin and packed cell volume were also observed from 48 hrs to 240 hrs. A significant increase (P < 0.01) in leucocytes count was noted throughout the exposure period. Elevated numbers of lymphocytes and eosinophils as found in the present study revealed lymphocytosis as well as eosinophilia, suggesting that this was a result of direct stimulation of the immunological defense due to the presence of a toxic substance or may be associated with tissue damage. The cytomorphological and cytopathological study of erythrocytes and leucocytes in malathion-exposed frogs at 0.006 ppm concentration revealed various cytotoxic effects at different exposure times. It was noted that the size and the shape of the erythrocytes were subjected to variation in different blood disorders. 相似文献
18.
Several monitoring programs have been set up to assess effects of atmospheric deposition on forest ecosystems. The aim of the present study was to evaluate effects on the understorey vegetation, based on the first round of a regional (the Netherlands) and a European forest monitoring program. A multivariate statistical analysis showed surprisingly similar results for both data sets; the vegetation appeared to be largely determined by the ‘traditional’ factors soil, climate, and tree species, but there was a small but statistically significant effect of atmospheric deposition. The effects of deposition include a slight shift towards nitrophytic species at high N deposition in the European network, and towards acidophytic species at high S-deposition in the Dutch network. The relatively small effect of atmospheric deposition is understandable in view of the very large natural variation in environmental conditions. Time series of both vegetation and environment are needed to assess deposition effects in detail. 相似文献
19.
Annemieke Farenhorst 《Journal of environmental science and health. Part. B》2013,48(3):265-269
Trifluralin is typically applied onto crop residues (trash, stubble) at the soil surface, or onto the bare soil surface after the incorporation of crop residues into the soil. The objective of this study was to quantify the effect of the type and amount of crop residues in soil on trifluralin mineralization in a Wellwood silty clay loam soil. Leaves and stubble of Potato (Solanum tuberosum) (P); Canola (Brassica napus) (C), Wheat (Triticum aestivum) (W), Oats (Avena sativa), (O), and Alfalfa (Medicago sativa) (A) were added to soil microcosms at rates of 2%, 4%, 8% and 16% of the total soil weight (25 g). The type and amount of crop residues in soil had little influence on the trifluralin first-order mineralization rate constant, which ranged from 3.57E-03 day?1 in soil with 16% A to 2.89E-02 day?1 in soil with 8% W. The cumulative trifluralin mineralization at 113 days ranged from 1.15% in soil with 16% P to 3.21% in soil with 4% C, again demonstrating that the observed differences across the treatments are not of agronomic or environmental importance. 相似文献
20.
Mette M. Broholm Catherine Crouzet Erik Arvin Christophe Mouvet 《Journal of contaminant hydrology》2000,44(3-4)
The biodegradation of phenols (5, 60, 600 mg l−1) under anaerobic conditions (nitrate enriched and unamended) was studied in laboratory microcosms with sandstone material and groundwater from within an anaerobic ammonium plume in an aquifer. The aqueous phase was sampled and analyzed for phenols and selected redox sensitive parameters on a regular basis. An experiment with sandstone material from specific depth intervals from a vertical profile across the ammonium plume was also conducted. The miniature microcosms used in this experiment were sacrificed for sampling for phenols and selected redox sensitive parameters at the end of the experiment. The sandstone material was characterized with respect to oxidation and reduction potential and Fe(II) and Fe(III) speciation prior to use for all microcosms and at the end of the experiments for selected microcosms.The redox conditions in the anaerobic microcosms were mixed nitrate and Fe(III) reducing. Nitrate and Fe(III) were apparently the dominant electron acceptors at high and low nitrate concentrations, respectively. When biomass growth is taken into account, nitrate and Fe(III) reduction constituted sufficient electron acceptor capacity for the mineralization of the phenols observed to be degraded even at an initial phenols concentration of 60 mg l−1 (high) in an unamended microcosm, whereas nitrate reduction alone is unlikely to have provided sufficient electron acceptor capacity for the observed degradation of the phenols in the unamended microcosm.For microcosm systems, with solid aquifer materials, dissolution of organic substances from the solid material may occur. A quantitative determination of the speciation (mineral types and quantity) of electron acceptors associated with the solids, at levels relevant for degradation of specific organic compounds in aquifers, cannot always be obtained. Hence, complete mass balances of electron acceptor consumption for specific organic compounds degradation are difficult to confine. For aquifer materials with low initial Fe(II) content, Fe(II) determinations on solids and in aqueous phase samples may provide valuable information on Fe(III) reduction. However, in microcosms with natural sediments and where electron acceptors are associated with the sediments, complete mass-balances for substrates and electron acceptors are not likely to be obtained. 相似文献