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861.
设计了一组对比实验 ,即城市固体废物 (MSW)好氧生物反应器与单纯好氧填埋方式的对比实验。其中MSW好氧生物反应器是强制通风好氧填埋和渗滤液循环两种填埋方式有机结合体。通过该对比实验研究两者对填埋的垃圾及所产生的渗滤液的降解情况 ,从而得出MSW好氧生物反应器有很好的降解效果  相似文献   
862.
硫化碱脱除二氧化硫工业烟气的可行性分析   总被引:7,自引:1,他引:6  
分析了国内外烟气脱硫的研究现状,论述了用硫化碱脱除二氧化硫化工业烟气在理论上和实验上的可能性。  相似文献   
863.
在以皮胶原为碳、氮源时其最适产酶条件为p H7 ,30 ℃,高产酶时间为4 d .经 Ca( O H)2 预处理革屑不能有效促进该菌对革屑的降解,但可使大部分 Cr3 + 沉淀而除去.经该株蛋白酶的粗提及性质实验,确定酶的最适反应条件为40 C、p H7 .0 ~8 .0 , Cr3 + 对酶有轻度的抑制作用,以2 .26 % 的粗酶作用于革屑,水解率达50 % 以上  相似文献   
864.
以工业废弃物聚苯乙烯泡沫塑料及电厂粉煤灰为主要原料,用适量轻溶剂油调制成油性腻子,搅拌均匀经三辊机或轮碾机研磨至完全均匀细腻,包装即得产品。该产品的性能与同类油性腻子相似,而制造成本显著降低,适用于填平金属、木质、混凝土物体表面的凹坑、针孔和缝隙,同时减少了白色污染物聚苯乙烯泡沫塑料废弃物对环境的污染。  相似文献   
865.
Environmental life cycle assessment (LCA) developed rapidly during the 1990s and has reached a certain level of harmonisation and standardisation. LCA has mainly been developed for analysing material products, but can also be applied to services, e.g. treatment of a particular amount of solid waste. This paper discusses some methodological issues which come into focus when LCAs are applied to solid waste management systems. The following five issues are discussed. (1) Upstream and downstream system boundaries: where is the ‘cradle’ and where is the ‘grave’ in the analysed system? (2) Open-loop recycling allocation: besides taking care of a certain amount of solid waste, many treatment processes also provide additional functions, e.g. energy or materials which are recycled into other products. Two important questions which arise are if an allocation between the different functions should be made (and if so how), or if system boundaries should be expanded to include several functions. (3) Multi-input allocation: in waste treatment processes, different materials and products are usually mixed. In many applications there is a need to allocate environmental interventions from the treatment processes to the different input materials. The question is how this should be done. (4) Time: emissions from landfills will continue for a long time. An important issue to resolve is the length of time emissions from the landfill should be considered. (5) Life cycle impact assessment: are there any aspects of solid waste systems (e.g. the time horizon) that may require specific attention for the impact assessment element of an LCA? Although the discussion centres around LCA it is expected that many of these issues are also relevant for other types of systems analyses.  相似文献   
866.
867.
ABSTRACT: Successful watershed management requires consideration of multiple objectives and the efficient use of scarce public and private resources. One way to address these multi-faceted issues is through Social Benefit-Cost Accounting (SBCA). SBCA is a systematic method of addressing complex social and economic issues relevant to proposed watershed management projects. Benefits of using this technique include: benefits and costs of watershed projects are better understood; politically sensitive issues tend to be put into perspective; and stakeholders' interests are placed on a level playing field. An example from Bogota, Colombia demonstrates how SBCA can be used to value the benefits and costs of a proposed project. By addressing the benefits and costs to all stakeholders, the design of watershed management programs can be improved to achieve goals in a cost-effective manner.  相似文献   
868.
ABSTRACT: The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian Region. Karst areas comprise about 18 percent of the Region's land area. An estimated one-third of the Region's farms, cattle, and agricultural market value are on karst terrain. The purpose of this study was to compare fecal bacteria densities in karst groundwater impacted by two primary agricultural land uses in central Appalachia. Fecal bacteria densities were measured in cave streams draining two primary land management areas. The first area was pasture serving a beef cow-calf operation. The second area was a dairy. Neither area had best management practices in place for controlling animal wastes. Median fecal coliform and fecal streptococcus densities were highest in cave streams draining the dairy. Median fecal coliform densities in the dairy-impacted stream were greater than 4,000 CFU/100 ml and the median fecal coliform densities in the pasture-impacted streams were less than 10 CFU/100 ml. Median fecal streptococcus densities in the same streams were greater than 2,000 CFU/100 ml and 32 CFU/100 nil, respectively. A second dairy, with best management practices for control of animal and milkhouse waste, did not appear to be contributing significant amounts of fecal bacteria to the karst aquifer. It was concluded that agriculture was affecting bacterial densities in the karst aquifer. New management practices specifically designed to protect karst groundwater resources may be one way to protect the groundwater resource.  相似文献   
869.
ABSTRACT: Climate change has the potential to have dramatic effects on the agricultural sector nationally and internationally as documented in many research papers. This paper reports on research that was focused on a specific crop growing area to demonstrate how farm managers might respond to climate-induced yield changes and the implications of these responses for agricultural water use. The Hadley model was used to generate climate scenarios for important agricultural areas of Georgia in 2030 and 2090. Linked crop response models indicated generally positive yield changes, as increased temperatures were associated with increased precipitation and CO2. Using a farm management model, differences in climate-induced yield impacts among crops led to changes in crop mix and associated water use; non-irrigated cropland received greater benefit since irrigated land was already receiving adequate moisture. Model results suggest that farm managers will increase cropping intensity by decreasing fallowing and increasing double cropping; corn acreage decreased dramatically, peanuts decreased moderately and cotton and winter wheat increased. Water use on currently irrigated cropland fell. The potential for increased water use through conversion of agriculturally important, but currently non-irrigated, growing areas is substantial.  相似文献   
870.
废催化剂浸出规律的静态实验方法   总被引:9,自引:1,他引:8  
利用静态浸出实验方法对废催化剂中重金属在不同固水比和浸出次数条件下的浸出规律进行了系统研究。实验发现浸出次数大于3次后,重金属的浸出浓度和浸出速率趋于稳定,同时固水比的增加也没有明显改变废催化剂中重金属的浸出。认为在浸取次数大于3次以后,随着表面溶质的溶解,浸出过程主要为内扩散所控制。  相似文献   
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