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1.
利用煤吸附处理含铬废水及生活污水的试验研究   总被引:4,自引:0,他引:4  
本文研究了四川白皎无烟煤用于生活污水、含铬废水和乐果生产废水的处理。在静态条件下,煤对生活污水中的COD去除率为12%;对乐果生产废水的脱色率大于638%;在含铬工业废水在浓度为3526×10-5mol·dm-3时Cr(VI)的去除率为90%左右。考察了固液比、温度、浓度和酸度等对煤吸附Cr(VI)的影响,并发现吸附量q与时间t之间遵从如下的定量关系:q=47685(1+21256t)-1或q=21351[1-exp(-05016t)]03838  相似文献   

2.
用分光光度法测定水中化学需氧量CODCr,通过正交试验选择氧化的最佳选择。试验结果表明对CODCr值为50~1000mg/L的水样:氧化剂K2Cr2O7用量为0.20~0.40mol/L,催化剂Ag2SO4用量为10g/LH2SO4,消解时间10min,加热温度180℃。用CODCr为138mg/L的质控标样进行验证试验,其绝对误差为0.5~3.0mg/L。与标准方法相比用分光光度法测定CODCr具有分析误差小,省时、省力,节约药剂的特点。  相似文献   

3.
采用新型载体的好氧流化床的动力学研究   总被引:1,自引:0,他引:1  
本文以稀释的味精废水为基质,对采用新型载体LSAR的好氧生物流化床进行动力学研究,求得动力学参数分别为γmax=8.81(gCOD/gvs.d),Ks=0289(gCOD/L),Kd=0.046d^-1,Y=0.16(gvs/gCOD)。其值基本处于文献的报导之内,说明以LSAR为载体的好氧微生物膜具有较好的活性,LSAR作为好氧流化床载体是可行的。  相似文献   

4.
人工湿地塘床系统净化地表水的试验研究   总被引:16,自引:2,他引:14  
成都市活水公园人工湿地塘床系统对枯水期府河水中的CODcr,BOD5,TN,TP,oil,LAS,Ar-OH,NH3,S^2-等污染物的去除率在85%以上,总大肠菌群的去除率达99.9%以上,其净化效果能够满足净化地表水或污水深度处理的需要。由此可见,人工湿地塘床系统是一种生态滤池。  相似文献   

5.
张卫星 《四川环境》1998,17(4):58-59
氯离子浓度高于500mg/L时,对CODcr的测定呈混浊干扰,通过加入HgSO4络合氯离子,可消除氯离子含量达2000mg/L的干扰,过量的HgSO4对CODcr结果无影响。  相似文献   

6.
测定污水中CODcr回流时间的探讨肖建寅,吴平胜(珠海市政管理处,珠海519015)化学需氧量(ChggiCCIOXygenDemand,简称COD)是指水体中易被强氧化剂氧化的还原性物质所消耗氧化剂的量,结果折算成氧的量(以mg/L计)。而以酸性介...  相似文献   

7.
为了快速监测油田废水中的化学需氧量CODCr,因此采用TL-1(A)型污水CODCr速测仪进行加热催化消解,然后再用分光光度比色法测定CODCr,实验中进行了方法的准确度、精确度及Cl-影响实验,并与标准的重铬酸钾法进行了对比实验,结果说明分光光度法简单快速、重现性较好、准确度较高,对同一产品的测定结果与重铬酸钾法非常一致。因此,本方法可用于油田废水中的CODCr监测。  相似文献   

8.
COD_(Cr)测定中排除氯离子干扰的进一步探讨   总被引:1,自引:1,他引:0  
废水中化学需氧量的测定采用重铬酸钾法[1],大多数情况下都存在Cl-干扰,其排除方法用HgSO4掩蔽,通过实验探讨不用剧毒药品HgSO4掩蔽Cl-的干扰,而用CODCr总量减去Cl-的量。实验结果表明:当测定化学需氧量较低而Cl-含量高的水样时,即使采用掩蔽Cl-也会产生较大的误差,而用测定值减去0.226[Cl-]之值更接近真值。  相似文献   

9.
采油废水COD_(cr)处理设计和实验研究   总被引:8,自引:1,他引:7  
针对某油田采油污水处理工艺不能有效去除COD_(cr),致使处理后水中的COD_(cr)不能满足GB8978-1996《污水综合排放标准》要求的情况,进行了采油废水COD_(cr)处理试验研究和工艺方案设计。通过小型动态试验研究,初步提出了经济上可行、技术上有效、流程较简单、运行安全可靠的废水治理方案,并确定了关键的技术参数。  相似文献   

10.
为了探讨火电厂除灰水中的粉煤灰(含炉渣)对炼油厂含碱污水中石油类、COD(cr)等污染物的吸附处理效果,根据某单位现场情况,将炼油厂含碱污水送入火电厂除灰沟→经充分混合排入储灰场→并经长时间沉降分离的流程进行模拟试验,结果表明:由于粉煤灰的吸附作用,显著降低了炼油厂含碱污水中的石油类、COD(cr)、挥发酚、碳化匕物等污染物。  相似文献   

11.
Projected Changes in Discharge in an Agricultural Watershed in Iowa   总被引:1,自引:0,他引:1       下载免费PDF全文
Our improved capability to adapt to the future changes in discharge is linked to our capability to predict the magnitude or at least the direction of these changes. For the agricultural United States Midwest, too much or too little water has severe socioeconomic impacts. Here, we focus on the Raccoon River at Van Meter, Iowa, and use a statistical approach to examine projected changes in discharge. We build on statistical models using rainfall and harvested corn and soybean acreage to explain the observed discharge variability. We then use projections of these two predictors to examine the projected discharge response. Results are based on seven global climate models part of the Coupled Model Intercomparison Project Phase 5 and two representative concentration pathways (RCPs 4.5 and 8.5). There is not a strong signal of change in the discharge projections under the RCP 4.5. However, the results for the RCP 8.5 point to a stronger changing signal related to larger projected increases in rainfall, resulting in increased trends, in particular, in the upper part of the discharge distribution (i.e., 60th percentile and above). Examination of two hypothetical agricultural scenarios indicates that these increasing trends could be alleviated by decreasing the extent of the agricultural production. We also discuss how the methodology presented in this study represents a viable approach to move forward with the concept of return period for engineering design and management in a nonstationary world.  相似文献   

12.
Over the last fifteen years, Environmental Assessment systems of transitional societies of Central and Eastern Europe and Central Asia have undergone dramatic change from appraisals integrated into centrally planned economies to formal procedures aimed to ensure interdisciplinary analysis of environmental impacts and linked to publicly accountable decision-making. In most Central European nations, EA systems have been radically reformed to approximate the procedures used in developed countries, particularly in the European Union. In contrast, EA in most of the former Soviet republics has been reformed more gradually and is still based on the so-called State Environmental Review procedure inherited from the USSR and substantially different from 'Western' EA. About one-third of the transitional countries (in the Balkans, the Caucasus and Central Asia) have, so far, failed to establish functioning EA systems. Throughout the region, there has been a gap between EA legislation and practice, especially concerning interdisciplinary analysis of environmental impacts, public participation, and utilisation of EA findings in decision-making. A key driving force in the reform of EA systems has been the change in their societal context, the so-called 'process of transition'. Three main policy agendas--environmental protection, reforms of decision-making, and conforming to international requirements--along with the institutional context of EA regulations and practice have influenced both the change of EA systems over time and the regional variations in the patterns of their evolution. This study suggests that an effective reform of an EA system should be context-sensitive, or be 'in gear' with the political and economic transition. Future EA research should consider their changing societal contexts and focused on practical effects of applying EA procedures.  相似文献   

13.
我国城市生态评价研究进展   总被引:2,自引:0,他引:2  
张翔  余红英  万鹏  杨渺 《四川环境》2009,28(3):89-93
城市建设带来了越来越多的生态环境问题,生态城市建设是解决这些问题的良好途径。生态城市的建设要有一定的评价体系作为支撑,本文综述了国内基于AHP方法建立的应用较为广泛的城市生态评价体系和方法,并对国内城市生态评价的现状做了分析。  相似文献   

14.
This article presents a case study from Mozambique of the electrification of two selected towns under a World Bank financed project. Low-cost electricity services were extended to the two isolated areas after an enabling framework had been created for private sector participation. The World Bank project also demonstrates that the private sector can be attracted to participate in rural electrification schemes even in a poor country. The example shown in this article is one of the few of its kind in SubSaharan Africa.  相似文献   

15.
As a result of Structural Adjustment Programme from the 1980s, many developing countries have experienced an increase in resource extraction activities by international and transnational corporations. The work reported here examines the perceived impacts of gold mining at the community level in the Wassa West District of Ghana, Africa and discusses those perceived impacts in the context of globalization processes and growing multinational corporate interest in Corporate Social Responsibility (CSR). Interview data compared community members' perceptions with those of company representatives in three communities. The results indicate that communities held companies responsible for a series of economic, social, and environmental changes. While recognizing some of the benefits brought by the mines, communities felt that the companies did not live up to their responsibility to support local development. Companies responded by denying, dismissing concerns, or shifting blame. Findings from this work show that lack of engagement and action by government agencies at all levels resulted in companies acting in a surrogate governmental capacity. In such situations, managing expectations is key to community-company relations.  相似文献   

16.
电催化氧化处理难降解废水技术研究进展   总被引:4,自引:1,他引:4  
电催化氧化处理难降解废水技术已得到了广泛关注.本文从电极材料与应用,电极结构及反应器形状,以及与其它处理方法联用等综述了最新研究进展,并在此基础上总结出了电催化氧化技术今后的发展方向.  相似文献   

17.
The preparation of strategic environmental assessment (SEA) inclusive sustainability appraisals (SAs) for neighbourhood plans (NPs) in England may be required when significant environmental effects are expected to arise from an NP. In this paper, we report on the result of a Ph.D. project, conducted between 2012 and 2015, in which all 15 NP SEA inclusive SAs that had been completed at the time were evaluated. In this context, the quality of SA practice was found to differ substantially. SAs were prepared either ‘in-house’ (i.e. by neighbourhood planning steering groups) or by consultants. The quality of SAs was found to be associated with their overall perceived degree of influence on the underlying NPs. Whilst the focus of this paper is on practice in England, findings are expected to be of interest to a wider international audience, in particular to those experimenting with voluntary neighbourhood/local level plan SA/SEA.  相似文献   

18.
Environmental Flows (EFlows) are defined as the quantity, timing and quality of the flow of water, sediment and biota necessary to sustain freshwater and estuarine ecosystems, and the human livelihoods and well-being that depend on these ecosystems. As such they are a vital component of Integrated Water Resource Management (IWRM). A recent survey found that, in general, Africa lags behind schedule with respect to the global SDG Target 6.5 to implement IWRM at all levels, including through transboundary cooperation as appropriate. This web-based review explores progress made in EFlows Assessments and implementing their outcomes in southern Africa. It outlines the apparent impetus to the uptake of EFlows provided by legislation, common funding mechanisms for EFlows assessment and evolving trends in EFlows assessment. It also highlights instances of implementation of EFlows in both in-country and transboundary settings.  相似文献   

19.
Rainfall samples were collected during the 2003 and 2004 growing seasons at four agricultural locales across the USA in Maryland, Indiana, Nebraska, and California. The samples were analyzed for 21 insecticides, 18 herbicides, three fungicides, and 40 pesticide degradates. Data from all sites combined show that 7 of the 10 most frequently detected pesticides were herbicides, with atrazine (70%) and metolachlor (83%) detected at every site. Dacthal, acetochlor, simazine, alachlor, and pendimethalin were detected in more than 50% of the samples. Chlorpyrifos, carbaryl, and diazinon were the only insecticides among the 10 most frequently detected compounds. Of the remaining pesticide parent compounds, 18 were detected in fewer than 30% of the samples, and 13 were not detected. The most frequently detected degradates were deethylatrazine; the oxygen analogs (OAs) of the organophosphorus insecticides chlorpyrifos, diazinon, and malathion; and 1-napthol (degradate of carbaryl). Deethylatrazine was detected in nearly 70% of the samples collected in Maryland, Indiana, and Nebraska but was detected only once in California. The OAs of chlorpyrifos and diazinon were detected primarily in California. Degradates of the acetanilide herbicides were rarely detected in rain, indicating that they are not formed in the atmosphere or readily volatilized from soils. Herbicides accounted for 91 to 98% of the total pesticide mass deposited by rain except in California, where insecticides accounted for 61% in 2004. The mass of pesticides deposited by rainfall was estimated to be less than 2% of the total applied in these agricultural areas.  相似文献   

20.
生物体内有机氯农药的研究进展   总被引:11,自引:0,他引:11  
徐亮  刘月雪  包维楷 《四川环境》2003,22(5):15-18,21
有机氯农药是高残留农药,进入生物体后会长期残留,对生物体产生危害。近年来,生物体中的有机氯农药的研究越来越引起各国环境化学家、生态学家的重视,渐渐成为环境化学、生态毒理学研究的热点之一。本文总结了近年来国际上有关生物体内有机氯农药的研究进展情况,以及所取得的主要研究成果。  相似文献   

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