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111.
Based on the experiments of utilization of garlic processing wastewater in a lotus pond, this study demonstrates that lotus pond wetlands have a remarkable ability to remove organic pollutants and decrease chemical oxygen demand(CODCr), biochemical oxygen demand(BOD5), and suspended substances(SS) in garlic processing wastewater. Results also show evident effects of lotus roots on absorption of NH3-N. The pH value in a lotus pond with wastewater discharged was relatively stable. The water quality in the lotus pond reached the class Ⅱ emission standard, according to the Integrated Wastewater Discharge Standard(GB8978-1996), seven days after pretreated garlic processing wastewater had been discharged into the lotus pond. Garlic processing wastewater irrigation does not produce pollution in the pond sediment and has no negative effect on the growth of lotus roots. Due to utilization of garlic processing wastewater, the output of lotus roots increased by 3.0% to 8.3%, and the quality of lotus roots was improved. Therefore, better purification and utilization results can be achieved. 相似文献
112.
It has been widely recognized that urban wastewater reuse is an alternative for water shortage problem. Although the improvement
on urban wastewater reuse in China is quite significant, the further development still requires more strategic regulating
and directing at the national level. However, due to the huge spatial differences in social–economic and resource conditions
among different areas in China, it is difficult to apply a same policy framework to the whole country. In the paper, the mainland
of China has been divided into 342 research regions and each region has one large-scale or medium-scale central city. The
paper tried to answer the question how to select the development pattern of urban wastewater reuse for each region. Firstly,
in order to evaluate the necessity and regional economic feasibility to develop urban wastewater reuse, an indicator system
with three indexes at the upper level and seven indicators at the lower level was build up. And valuing method and the weight
for each indicator was given. All the research regions covering the mainland of China has been scored with the indicator system.
Secondly, the national strategic zoning has been done with the key method of cluster analysis. All regions have been sorted
into five types of strategic development zones. Each zone has its own wastewater reuse development option such as Preferential
Imperative Development, State Supporting Development, Self Supporting Development, Waiting for Development, and Non-Mandatory
Development. Thirdly, the corresponding policy suggestion for each zone was given to the government. The possible updates
between the different development patterns have been discussed as well. 相似文献
113.
TNT炸药废水三维电解氧化实验研究 总被引:2,自引:0,他引:2
以不锈钢作为阳极的三维电解反应器对废水的实验研究表明:在最佳电解条件下(极板间距4 cm、电压15 V、pH为3,绝缘粒子与活性炭粒子质量比为0.3,电流强度0.15 A时),电解3 h后TNT和COD的去除率分别为93 %和78 %.并探讨了电化学氧化处理TNT废水的机理. 相似文献
114.
采用厌氧—缺氧—ALMBR工艺处理焦化废水。在充填了横断面具有蜂窝胞壁结构纤维滤料的厌氧池和缺氧池中收集池内出气作为气源回曝气池中,在缺氧的条件下形成气升循环。好氧池为气提升三相循环流化床结构的MBR(ALMBR),不设二沉池,MLSS高达11~12 g/L。连续3个月的试验表明,焦化废水进水COD_(Cr)1950 mg/L、NH_3—N 150 mg/L时,出水COD_(Cr) 144 mg/L、NH_3—N 9.8 mg/L。工艺具有良好的抗冲击负荷能力,能够维持较高的污泥浓度,运行稳定,操作简单且管理方便。装有蜂窝胞壁填料的缺氧池COD_(Cr)去除率明显高于装有软性纤维填料缺氧池。 相似文献
115.
Aija Kosk 《Lakes & Reservoirs: Research and Management》2001,6(3):231-235
Lake Peipsi is the fourth largest lake in Europe and the largest international lake in Europe. Lake Peipsi is shallow, eutrophic, biologically very productive and is bordered by many wetland areas along its coasts. Large peat deposits in the Lake Peipsi basin are protected under national legislation. The lake is most important as a resource for recreation and fisheries. The fish stock in Lake Peipsi is one of the richest in Europe. The most critical environmental issues for the Peipsi watershed are eutrophication and unregulated fishing in the lake. During the Soviet period, large collective farms dramatically accelerated eutrophication. Despite the drop in fertilizer use during the last 10 years and a decrease in the number of domestic animals in the watershed, the impact of the earlier agricultural pollution is still significant. Untreated sewage has also been dumped in the Narva River tributary as a result of an international dispute concerning water supply and wastewater treatment. People living in the Lake Peipsi region have faced traumatic changes as a result of the re‐establishment of the border between Russia and Estonia in 1992. The establishment of an international border on the waters of the lake has resulted in fishermen losing access to many of their traditional fishing areas. Political and economic transformations of the last 10 years have seriously interrupted information exchange between different institutions and organizations concerned with the health of the lake. The Centre for Transboundary Cooperation facilitates international communication and cooperation between the Estonian and Russian governments and promotes public participation in environmental, social and economic development and decision‐making. The centre is in the process of guiding the development of a watershed management plan for the Lake Peipsi watershed and a vision for watershed development that is truly sustainable. 相似文献
116.
117.
深圳河湾水系生态需水的污水资源化 总被引:1,自引:0,他引:1
以深圳河湾水系为例,探讨以污水资源化再生水满足城市水系生态需水的方法。该方法统一考虑河流的水量水质需求,计算不同截污率和补水水质条件下河流的生态需水量;根据生态用水的供需平衡情况,确定污水资源化规模与水质要求。在此基础上,设计污水资源化的处理工艺以及再生水厂等的分布;并通过数学模型预测补水方案对水环境改善的效果。本研究为面向城市水系生态补水的污水资源化工程规划提供了科学的方法。 相似文献
118.
厌氧折流反应器对硝基苯冲击负荷适应性的研究 总被引:1,自引:0,他引:1
在9L、4格室的厌氧折流反应器(ABR)中,处理以葡萄糖为共基质的含硝基苯废水,温度为5~10℃,进水COD浓度为200~400mg/L,HRT为3h。结果表明ABR对有毒废水浓度变化的适应能力强,当进水硝基苯的浓度为0.48mg/L时,出水COD在21天恢复正常,运行稳定,反应器经硝基苯连续3天冲击(0.48mg/L)后,经历了原有微生物死亡、新微生物生长直到最终顶级群落和稳定发酵类型的形成的过程。 相似文献
119.
120.
In this study we argue that there is an interconnection between; the mechanistic worldview and competition, and the organic worldview and cooperation. To illustrate our main thesis we introduce two cases; first, Max Havelaar, a paradigmatic case of how business might function in an economy based upon solidarity and sustainability. Second, TINE, a Norwegian grocery corporation engaged in collusion in order to force a small competitor out of the market. On the one hand, in order to encourage market behaviour that integrates economic, societal and environmental values we find that transparent cooperation within a context of an organic worldview takes care of important intrinsic as well as instrumental values. On the other hand, we find evidence for asserting that cooperation based upon a mechanistic worldview, typically leads to group egotistical consequences undermining the long term common good. 相似文献