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51.
    
Song  Xiao  Ma  Jiao  Gao  Jiandong  Liu  Yanbo  Hao  Yongce  Li  Wei  Hu  Ruhai  Li  Aimin  Zhang  Lei 《Journal of Material Cycles and Waste Management》2017,19(1):496-504
Journal of Material Cycles and Waste Management - Bio-drying has been proved to be a promising method for treatment of MSW (municipal solid waste) and sewage sludge due to its high energy...  相似文献   
52.
Marine product collecting permits are useful management tools for providing information on usage patterns. Unfortunately, usage parameters based on permit issuance are invariably inaccurate because of permit noncompliance. Since noncompliance is a prosecutable offense, any attempt to estimate the rate of noncompliance by direct survey techniques is met with misleading and evasive responses. It has been shown elsewhere that randomized response designs reduce survey response bias to incriminating questions by ensuring respondent anonymity. With the use of the randomized response survey technique, estimates of permit noncompliance were determined for the Capricornia Section of the Great Barrier Reef Marine Park. Noncompliance with the requirement to obtain the prescribed permit was found to be low whereas, once a permit was obtained, noncompliance with specific permit conditions was considered high. Reasons for the high rate of noncompliance with specific conditions are presented, and it is recommended that marine park managers should not unreservedly base management decisions on usage data derived simply from permit issuance.  相似文献   
53.
    
ABSTRACT: The use of peatlands as the main form of wastewater treatment in a northern climate was studied for the James Bay Energy Society. The Fontanges campsite (70° 17′ 30″ W; 54° 34′ 00″ N) was chosen as the study site. In less than 1.5 km from the point of discharge BOD5, COD, total hardness, inorganic carbon, orthophosphates, total phosphorus, ammonia and total nitrogen were reduced by at least 90 percent. The peatland treatment system studied is divided into four components, each having a specific function. The first part combines the action of microorganisms and adsorption on peat, thus reducing the organic content while increasing the inorganic constituents. The second part uses peat to adsorb the inorganic elements already present in the wastewater and those produced in the first part of the system. The third component acts as an aerator, increasing the dissolved oxygen and decreasing the BOD5 levels of the water. The fourth part removes most of the remaining nutrients, thus acting like a tertiary treatment. Overall, peatlands seemed to be effective in treating domestic settled wastewater in a cold climate.  相似文献   
54.
Global climate change will influence environmental conditions including temperature, surface radiation, soil moisture, and sea level, and it will also significantly impact regional-scale hydrologic processes such as evapotranspiration (ET), precipitation, runoff, and snowmelt. The quantity and quality of water available for drinking and other domestic usage is also likely to be affected by changes in these processes. Consequently, it is necessary to assess and reflect upon the challenges ahead for water infrastructure and the general public in metropolitan regions. One approach to the problem is to use index-based assessment, forecasting and planning. The drought indices previously developed were not developed for domestic water supplies, and thus are insufficient for the purpose of such an assessment. This paper aims to propose and develop a “Metropolitan Water Availability Index (MWAI)” to assess the status of both the quantity and quality of available potable water sources diverted from the hydrologic cycle in a metropolitan region. In this approach, the accessible water may be expressed as volume per month or week (i.e., m3/month or m3/week) relative to a prescribed historical record, and such a trend analysis may result in final MWAI values ranging from ?1 to +1 for regional water management decision making. The MWAI computation uses data and information from both historical point measurements and spatial remote-sensing based monitoring. Variables such as precipitation, river discharge, and water quality changes at drinking water plant intakes at specific locations are past “point” measurements in MWAI calculations. On the other hand, remote sensing provides information on both spatial and temporal distributions of key variables. Examples of remote-sensing images and sensor network technologies are in-situ sensor networks, ground-based radar, air-borne aircraft, and even space-borne satellites. A case study in Tampa Bay, Florida is described to demonstrate the short-term assessment of the MWAI concept at a practical level. It is anticipated that such a forecasting methodology may be extended for middle-term and long-term water supply assessment.  相似文献   
55.
    
The reuse of waste materials requires the development of assessment methods for the long-term release of pollutants (source term) from wastes (or materials containing wastes) in contact with water. These methods depend on the scenario conditions: characteristics of the materials (especially physical structure and composition), contact with water. The scenario studied here is a water storage reservoir for fire fighting. The reservoir construction is made of a mixture of hydraulic binders and air pollution control (APC) residues from a municipal solid waste incinerator (MSWI). The modelling of the source term is performed in 5 steps ranging from the physico-chemical characterisation of the material to the validation of the proposed model by means of field simulation devices. This article presents the first steps of the methodology: physico-chemical characterisation of the source term, identification of the main transfer mechanisms and laboratory scale modelling of the source term. During the physico-chemical characterisation, it has been shown that the solidified waste shows a high basic capacity and that a relative decrease in pH during leaching favours retention of the main pollutants. During the first leaching sequences, the dynamic leaching tests show that the release of pollutants such as cadmium, arsenic, zinc and lead is extremely low but that the release of alkaline species (sodium and potassium) and chloride is very high from the beginning, whereas the release of calcium remains very high even after 3600 h of leaching. Identification of the main transfer mechanisms concludes that the release of soluble pollutants is the combined result of diffusional transfer of pollutants in the solution and the physico-chemical specificity of the species. The modelling based on these features enables a good simulation of the release but reveals a deviation from the experimental results after 500 h for alkaline species and 1000 h for Ca and Cl leaching. However, this deviation only appears after release of the major part of these elements.  相似文献   
56.
气相色谱法直接测定水中微量有机胺   总被引:2,自引:0,他引:2  
侯秀华  高明华  梁云  赵璞 《化工环保》2006,26(2):160-162
用配有氢火焰离子化检测器(FID)的气相色谱仪直接测定水中多种微量有机胺。试样经过滤后直接进样,在气相色谱仪上使用CP7448毛细管柱,用外标法测定水中微量甲胺、二甲胺、一乙胺、二乙胺的含量。在所选择的色谱操作条件下,甲胺、二甲胺、一乙胺、二乙胺的质量浓度分别在一定范围内与峰面积呈良好的线性关系。4种组分的回收率分别为96.7%,99.0%,101.2%,99.2%;精密度分别为4.3%,3.7%,5.5%,3.1%;检出限分别为2.0,2.0,1.5,1.5mg/L。该方法操作简便,回收率、精密度高。  相似文献   
57.
CO2资源化利用的现状及前景   总被引:4,自引:2,他引:4  
介绍了CO2分离捕集最新工艺——电化学法、膜法、化学循环燃烧法的研究进展。评述分析了CO2的各种资源化应用前景:CO2气体用作生物碳源、辅助注射成型剂及有机物(如氨基甲酸酯、表面活性剂)合成原料等;液态CO2用于人造金刚石、热泵干燥、超临界CO2萃取及固体干冰冷喷射清洗等。CO2作为一种潜在的丰富碳源,应不断研发其新的应用领域,加快其工业化应用。  相似文献   
58.
用膨润土处理油田污水的研究进展   总被引:1,自引:0,他引:1  
介绍了膨润土的基本特性及其存油田污水处理中的研究情况。天然膨润土经改性后,可吸附去除油田污水中的油、烃类衍生物、注聚残留聚合物及表面活性剂;负载金属氧化物的改性膨润土可对光催化氧化产生协同效应,提高光催化氧化油田污水中有机物的能力;在高压下将膨润土制成薄膜,对油田污水中的无机离了有一定的截留去除作用。  相似文献   
59.
用微孔填充理论研究活性炭对有机气体的吸附性能   总被引:1,自引:1,他引:1  
用微孔填充理论研究了活性炭C40/4对丙酮、甲苯、二氯甲烷有机气体的吸附性能,测试了该活性炭对3种有机气体在不同温度下(288.15,293.15,298.15K)的吸附结果。用D—R方程处理了实验数据,建立了3种有机气体在活性炭C40/4上的等温吸附模型,并将实验测试值与理论预测值进行了比较。实验结果表明:微孔填充理论及D—R方程可很好地描述活性炭C40/4对有机气体的吸附性能,理论预测值与实验测试值的平均相对误差小于3%;有机气体分压较高时,由于发生毛细凝聚,理论预测值较实验测试值偏低。  相似文献   
60.
干法腈纶生产废水脱氨氮研究   总被引:1,自引:0,他引:1  
采用本实验室富集驯化的高效硝化细菌对生化处理后的干法腈纶生产废水进行了脱NH3-N研究,在连续运行装置中考察了DO和MLSS的变化特征,并研究了废水NH3-N负荷和COD负荷对脱NH3-N效果的影响.实验结果表明:该菌能适应干法腈纶生产废水中的难生物降解物质并有效去除废水中的NH3-N,启动期DO呈现高-低-高的变化,运行期污泥增长速率呈现S型变化;进水NH3-N负荷达到0.405 kg/(m3·d)时仍能维持出水P(NH3-N)在5 mg/L以下,进水COD负荷由0.126 kg/(m3·d)提高到0.975 kg/(m3·d)的过程中,NH3-N去除率始终高于96%.  相似文献   
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