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1.
通过污染源筛选,采用对照区、污染区、清洁区优化的控制性布点与功能性布点方法,对典型工业污染源锦州石化分公司周边地下水基础环境状况进行调查和监测,掌握了背景、常规、特征污染因子污染状况及污染物分布时空规律,监测结果显示,除亚硝酸盐、阴离子洗涤剂等个别生活类污染因子和石油类超标外,其余监测因子均达标。石化行业特征因子石油类所有点位全部超标,说明锦州石化分公司已对周边地下水造成污染扩散影响。  相似文献   

2.
大连石化公司运用标准化法对该厂污染源进行了普查,进而对污染源做出了评价。以二蒸馏装置为例,对总排放口污染源的监测数据进行了标化处理,确定了主要的污染因子及污染源:石油类主要来自减压塔顶分离器;硫化物主要来自减压塔顶油、水分离器和常压塔顶油、水分离器;挥发酚主要来自减压塔顶油、水分离器。  相似文献   

3.
郑少辉 《四川环境》2022,(5):137-142
北方干河流域径流受到外部温度的影响,容易产生较大的潜在蒸发量,影响累积污染排放率,导致污染削减强度过小,污染分析结果不准确,针对该问题,研究北方干河流域径流面源污染特性及污染负荷建模分析。采用水文循环作为径流驱动力,数值分析北方干河流域径流影响因子,确定面源污染的扩散速度,输出面源污染特性,采用SCS径流曲线模拟地表流量数值,确定潜在蒸发量数值,控制累积污染排放率,构建径流面源污染特性及污染负荷模型,完成北方干河流域径流面源污染特性及污染负荷建模分析。采集径流污染数据,输入面源污染数据,对比测试结果表明:该模型的削减强度数值最大,符合实际径流面源污染态势。  相似文献   

4.
以海洋沉积物为研究对象,通过动态模拟实验研究了海洋沉积物中石油类污染物释放的影响因素及各条件下上覆水体中污染物浓度随时间的变化规律。实验结果表明,海洋沉积物中石油类污染物释放强度与沉积物土壤颗粒是否悬起有关,当土壤颗粒大量悬起时污染物释放强度得到显著提高;上覆水体盐度的增加抑制了石油类污染物的释放;海洋沉积物在一定的受污染范围内,随着受污染程度的增加,石油类污染物的释放强度会随之增加;上覆水体中石油类污染物的浓度与反应物的固液比成正相关。  相似文献   

5.
通过对大港油田某站场建设项目区域水文地质条件模型概化,建立地下水数值模型。对模型识别与验证,并选取石油类作为预测特征污染因子,应用数值法对石油类污染物在潜水层运移情况进行了预测和评价。预测结果表明,在30d时间内,石油类没有发生明显运移,污染源得到有效控制后,模型显示污染物浓度大幅下降,在第1 000d时,污染物浓度降低至0.04mg/L,几乎接近于零,污染物对周边地下水几乎无影响。  相似文献   

6.
我国城市径流所导致的面源污染问题严重,雨水自流过滤设施因其占地面积小、易于维护成为控制径流污染的末端处理设施之一。上海市临港新城某桥下建立雨水自流过滤净化设施示范工程,以控制进入滴水湖引清河道的水质。对该示范工程进行了处理效果监测,在长达一年半的时间里实地取样分析了六次有效降雨和两次模拟降雨数据,得到道路雨水径流经滤井处理前后的水质情况,分析结果表明:该自流过滤净化设施能够有效去除径流中的SS、石油类等污染物,去除率可达60%以上;对TN、COD_(Cr)、NH_4~+-N、TP等污染物有部分去除效果。  相似文献   

7.
微生物强化修复盐渍化石油污染土壤研究*   总被引:2,自引:0,他引:2  
采集东营地区石油污染土壤,进行微生物修复实验研究。考察投加复合菌株CM-13是否能够加速生物修复进程以及土壤中石油污染物质降解的影响因素。石油污染土壤经过90 d的处理,在含水量一定的前提下,复合菌株CM-13对于石油污染物质的加速降解作用显著,当复合菌株CM-13接种量为土壤质量的10%时修复效果较好。微生物的生长与营养盐的量存在最佳匹配值,土壤中氮的最佳含量为0.20%,磷的最佳含量为0.05%。实验中随着麦糠投加量的增大,石油类的降解率逐渐增大,当麦糠量为土壤体积分数的25%时,对土壤的修复效果最好。  相似文献   

8.
研究一般地下水弱碱性水溶液中,高铁酸钾对低浓度石油烃类污染物的氧化去除率.采用0#柴油模拟石油类污染物试验水样,氧化反应在200mL烧杯中模拟完全混合状态完成.实验分析浓度分别为5.02mg/L、2.05mg/L、1.01mg/L和0.52mg/L4个水样石油类污染物氧化去除率.实验研究显示,石油类污染浓度与高铁酸钾浓...  相似文献   

9.
区域地下水环境的保护是气田开发过程中环境保护工作的重点之一。通过现场调查和统计分析得知,外部污染源是影响当地地下水环境的主要因素,农田径流污染源是外部的主要污染源,以CODCr计其排放量分别约占外部污染源排放总量的67%,而钻井液漏失、天然气窜层、钻井废水排放等钻井作业是内部的主要污染源,其CODCr排放量约占内部污染源CODCr排放总量的62%,因而钻井作业的污染防治应是项目内部地下水污染防治工作的重点。根据地下水环境质量现状分析及变化趋势分析可知由于气田的开发建设,气田区地下水水质已受到一定程度的影响,特征污染物表现为CODCr、氨氮、氯化物、硝酸盐氮。为保护气田区地下水环境,分施工期和运营期两阶段设计了地下水环境保护方案,采取源头控制的清洁生产,至末端控制的污染治理并提出了突发污染事故应急预案,为气田的可持续开发提供指导。  相似文献   

10.
农业生态环境污染监测技术探讨   总被引:2,自引:0,他引:2  
农业生态环境污染监测是以农产品污染监测为中心的各环境要素的污染监测。依据农业区域中污染源排放危害农产品的特征污染物选择大气环境污染物、水环境污染物、土壤环境污染物、农产品污染物作为监测指标;依据农业区域中各类污染源的特点布设大气环境污染、水环境污染、土壤环境污染、农产品污染监测点位;在农产品生长期或生产期,大气环境污染及水环境污染同步监测一次,农产品污染在收获时监测一次,依据污染源污染物排放强度确定土壤环境污染监测频次。  相似文献   

11.
ABSTRACT: Fecal contamination and organic pollution of an agricultural drainage in northeast Indiana was high. Bacterial counts (total coliform, TC; fecal coliform, FC; and fecal streptococcus, FS) and biochemical oxygen demand (BOD) were used to assess waste concentrations. Coliform counts indicated that sections of the drainage receiving septic effluent had waste concentrations far in excess of public health standards (mean FC = 550,000/100 ml). Areas of drainage remote from septic tank pollution were found to occasionally meet federal public health standards for whole body contact recreation but generally these areas had twice the allowable limit of 200 FC/100 ml. Bacterial contamination was highest during runoff events when the median values for TC, FC, and FS were 5, 3, and 17 times greater, respectively, than the median values during low stream discharge. Surface flows carried contaminants from unconfined livestock operations and fecally contaminated sediment was transported by high waters. During one runoff event a BOD loading of 36.7 kg/km2 was recorded and the peak BOD concentration observed was 16 mg/l. A discharge of liquid manure from a confined livestock operation caused a major fish kill. Pollution from septic tanks and unconfined livestock is greatest at high stream discharge when dilution reduces the impact on aquatic life.  相似文献   

12.
针对彭州市西河水库污染现状及污染来源特征,为有效限制和处理入库径流污染物,结合库区自然条件,集成了"生态护坡—岸边人工湿地—人工浮岛"综合防控技术,并设计建设了示范工程。工程运行监测结果表明:经示范工程处理过的径流来水,除总氮以外,其他指标可以达到地表水Ⅲ类标准要求,其中,来水总氮平均超标63%,出水总氮平均超标24%,工程平均削减总氮23.93%。"生态护坡—岸边人工湿地—人工浮岛"综合防控技术及示范工程在西河水库径流污染防控方面发挥了积极作用,可以为类似水源污染防控提供技术参考。  相似文献   

13.
ABSTRACT: Estimates were made of petroleum hydrocarbon pollution loadings reaching the Delaware Estuary by determining storm event loadings of hydrocarbons from four storm sewers, draining areas of different land uses. Although refinery effluents constituted the largest source of petroleum pollution in 1975, it appears that after completion of currently required treatment processes urban runoff will be the largest remaining source of petroleum pollution. The petroleum in urban runoff resembles used crankcase oil in composition and contains toxic chemicals such as polynuclear hydrocarbons. Further research is clearly desirable. Remedial programs to control such pollution may be warranted on the basis of information now available.  相似文献   

14.
ABSTRACT: Bacterial densities (total coliform, fecal coliform, and fecal streptococci) and suspended solids in runoff from a feedlot, pasture, and corn field were measured. Densities of fecal coliform were highest from the feedlot but were 1000 to 10,000 times greater than the water quality standard for swimmable waters from all three land uses. Densities of fecal streptococci were highest from the corn field, which suggests that wildlife are the source of bacteria. Fecal coliform/fecal streptococci ratios distinguished cattle from wildlife as the source of bacterial pollution both among land uses and among seasons of the year. Suspended solids concentrations in runoff ranged from 423 to 925 mg/l and were highest from the corn field. A Geographic Information System (GIS), which utilizes a raster or grid-cell format, was developed to include algorithms associated with non-point source pollution. The system accepts digitally mapped information on soil type, topography, and land use. It calculates characteristics such as slope and slope length, and relates these characteristics to soils and land use parameters in order to produce three dimensional maps of runoff potential, sediment pollution potential, and bacterial pollution potential. It offers the advantages of retaining the geographic character of pollution potential information and of conveying in three-dimensional graphical terms the effects of topography, soil type, land use, and land management practices.  相似文献   

15.
To reduce nonpoint source pollution from nutrient, chemical, and sediment runoff, a number of environmental policy standards have been proposed. Such standards could be used to reduce nonpoint source pollution from nutrient, chemical, and sediment runoff to impaired water bodies. State governments can use voluntary approaches to meet nonpoint source pollution reduction goals. However, the practices that lower net returns will not be voluntarily adopted by farmers. Crop rotations and tillage practices may help producers to comply with the environmental standards while minimizing losses in farm profits. This study compares runoff from crop rotation practices and conventional continuous row cropping systems in Mississippi. The results are compared for different tillage systems in order to examine robustness of results. Nutrient runoff and sediment runoff are simulated using the Erosion Productivity Impact Calculator (EPIC). Sensitivity analysis of the sediment and nitrate reductions at 15 percent, 25 percent, and 35 percent are conducted. Under these scenarios, net returns are optimized under environmental constraints, and the marginal cost of sediment reduction ranges from US$1.61 to US$9.63 per ton depending on soil conditions, while the corresponding nitrate and phosphorus reductions costs range from US$1.21 to US$7.08 per kg and from US$0.09 to US$31.91, respectively. The empirical results from this study indicate that a nitrate reduction policy is relatively less costly than a sediment reduction policy. The results also demonstrate the importance of geophysical conditions and policy costs, which vary across regions.  相似文献   

16.
ABSTRACT: The hydrologic responses from an agricultural watershed in southeast Nebraska were investigated under an array of physiographic, hydrologic, meteorologic, and management conditions. For analytical purposes, the hydrologic responses were narrowed to include only runoff and sediment yield. The study was performed by utilizing the ANSWERS (Areal Nonpoint Source Watershed Environment Response Simulation) hydrologic-simulation model. Results of this study indicate that, generally, nonstructural (agronomic) Best Management Practices (BMPs) have a more significant impact in controlling erosion and nonpoint-source pollution than structurally oriented BMPs. The percentage of reduction in average soil loss as a result of changing tilage systems from conventional to chisel plow was in the mid-40s. The corresponding percentages of reduction in sediment yield from the watershed under minimum tillage and no-till systems were in the mid-60s and mid-80s, respectively. The impact of these management strategies on runoff varied considerably. That is primarily based on the watershed's antecedent soil moisture condition, land use, and the growth stage of crops. Generally, an intense, short, thunderstorm type of rainfall event had more relative impact on runoff, and therefore sediment yield than a long, gentle, and steady event.  相似文献   

17.
成都市径流污染的概念性模型   总被引:7,自引:0,他引:7  
施为光 《四川环境》1994,13(2):65-70
概念性模型是根据城市径流形成过程及对水体影响变化的物理机理建立的一套数学模型,模型及参数均有明确的物理意义。本文用概念性模型求出了成都市街道地表物的累积量,降雨径流污染负荷量,并模拟了污染物对受纳水体的影响。  相似文献   

18.
Soil loss and surface runoff patterns were studied in erosion plots developed on manmade steep slopes (60 percent) over three years (1997–2000) in which rainfall ranged from 1338.4 to 1429.2 mm/year. Surface runoff and soil loss was examined under three different rainfall intensity classes. Runoff was mainly controlled by the rainfall distribution pattern on the seasonal scale. The soil loss was influenced by runoff during the first year. Both soil loss and runoff were reduced due to bioengineering measures in the first year irrespective of species planted. In the third year, combined effects of growth of grasses on protected plots, soil compaction and sediment exhaustion was noticed on runoff and soil loss. This was reflected by reduction in the runoff and soil loss from untreated and treated plots. In the high intensity class, reduction in runoff in treated plots was about 50 percent in three years and reduction in soil loss ranged between 94–95 percent in all plots. Physical treatment with brushwood structures was more efficient in erosion control in the low intensity class.  相似文献   

19.
ABSTRACT: Simulated rainfall was used on experimental field plots to compare the effect of chemical fertilizer and sludge application on sediment, nitrogen, and phosphorus in runoff from no-till and conventional tillage systems. Chemical fertilizer application under the no-till system resulted in the least amount of total N and P in surface runoff. However, sludge application under the no-till system resulted in the least amount of NO3-N and sediment in surface runoff. The worst water quality scenarios were observed when either sludge or chemical fertilizer were surface-applied under a conventional tillage system. Nitrogen losses from the conventional tillage system were minimized when sludge was incorporated into the soil. However, phosphorus and sediment yield from such a system were significantly higher when compared to phosphorus and sediment yield from the no-till system. The results from this study indicate that the use of sludge on agricultural land under a no-till system can be a viable alternative to chemical fertilizer for nitrogen and phosphorus control in runoff. A more cautious approach is recommended when the sludge is incorporated into the soil in a conventional tillage system because of potential for high sediment and phosphorus yield in surface runoff.  相似文献   

20.
ABSTRACT: Increasingly, residential development in urbanizing areas is accomplished by large housing projects, composed of clusters of townhouses or garden partments. It is hypothesized that the runoff from such developments should carry more pollution than that from the same number of housing units on separate plots, because the runoff is conveyed directly to drainage channels rather than being drained across lawns and gardens, which may absorb part of the pollutants. In order to evaluate this effect, storm event data were obtained from a planned unit development near Hightstown, N. J., using samples taken every 10 minutes throughout the storm at two different storm sewers. Results show heavy metals pollution about what had been anticipated, in accordance with the hypothesis given above, and BOD ammonia and phosphates higher than predicted. The results are significant for areawide water quality planning in metropolitan areas, where projections of future pollution loadings depends upon the land use.  相似文献   

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