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561.
Creta Farm Plc, owns the largest meat producing (pigs rearing), processing and packaging unit in the island of Crete, in Greece, placed outside the city of Rethymnon in the north coast of the island. From the farm, where more than 20 000 pigs of various ages and sizes live, 300–320 m3 of wastewater are collected in a daily basis. From the slaughterhouse and the processing unit another 100–125 m3/d are produced. The wastewater treatment system is a combination of settling and aeration tanks, with decanters operating in different phases of the process, mainly for the removal of the solids from the wastewater. The average biochemical oxygen demand and total suspend solids values of the treated effluent are 40 and 80 mg/l, respectively. From this almost secondary treated effluent about 100 m3 are used for cleaning the sewage pipes of the rearing unit (animals houses). The remaining 300 m3 are disinfected with a weak chlorine solution before used for irrigating trees, grass and various other plants. More than 2000 eucalyptus trees, 1500 tamarix trees and a large number of olive trees are growing in the site creating a pleasant view and at the same time help minimising the odour problem.  相似文献   
562.
ABSTRACT: The Louisiana Environmental Management System (LEMS) is a data processing program developed to aid the Louisiana Joint Legislative Committee on Environmental Quality in decisions leading to resources legislation. Serving as a central data collection and retrieval point for various agencies, the LEMS will maintain assembled information on the location of monitoring stations and coordinate the files of user agencies with data on: land use; air and water quality; meteorological, climatological, and hydrological phenomena; vegetation; fish and wildlife conservation; population; and economics. This data is geographically stored in relation to the state plane coordinate system. For decision making, all pertinent hydrologic, topographic, engineering, cadastral, and other information from separate sources can be automatically mapped as a combined overlay to one of three chosen scales. Land-use patterns are the input data for iterative analyses of present conditions and simulated future human activities for assessing the environmental impact of proposed multiple-purpose water resource developments.  相似文献   
563.
Melt-pressed films of polycaprolactone (PCL) and poly(lactic acid) (PLA) with processing additives, CaCO3, SiO2, and erucamide, were subjected to pure fungal cultures Aspergillus fumigatus and Penicillium simplicissimum and to composting. The PCL films showed a rapid weight loss with a minor reduction in the molecular weight after 45 days in A. fumigatus. The addition of SiO2 to PCL increased the rate of (bio)erosion in A. fumigatus and in compost. The use of a slip additive, erucamide, was shown to modify the properties of the film surface without decreasing the rate of bio(erosion). Both the rate of weight loss and the rate of molecular weight reduction of PCL increased with decreasing film thickness. The addition of CaCO3 to PLA significantly reduced the thermal degradation during processing, but it also reduced the rate of the subsequent (bio)degradation in the pure fungal cultures. PLA without additives and PLA containing SiO2 exhibited the fastest (bio)degradation, followed by PLA with CaCO3. The degradation of the PLA films was initially governed by chemical hydrolysis, followed by an acceleration of the weight change and of the molecular weight reduction. PLA film subjected to composting exhibits a rapid decrease in molecular weight, which then remains unchanged during the measurement period, probably because of crystallization.  相似文献   
564.
The optimal pH and temperature, maximum specific degradation rate, half rate constant and flocculation rate for the hybrid cell Foaz were measured in the reaction for the degradation of soybean processing wastewater(SPW) in this study. The optimal pH and temperature for Foaz in SPW were the same as those of its parental strains Saccharomyces cerevisiae Y9407 and Rhodobacter sphaeroides P9479, but the flocculation rate, the maximum specific degradation rate and the half rate constant for Foaz were higher than those of its parental strains. The results suggest that the characteristics of the inter kingdom fusant Foaz constructed from the protoplast fusion between the eukaryote cell yeast S.cerevisiae and the prokaryote cell photosynthetic bacteriaR. sphaeroides may favor degrading organic pollutant in SPW and removing biomass from the effluent.  相似文献   
565.
波形炉胆是小型卧式锅壳式燃油燃气锅炉的重要部件 ,它的质量直接影响着锅炉的正常运行。采用模型压制成形工艺制造波形炉胆存在诸多缺点 ,难以保证其制造质量。文中介绍的波形炉胆旋压成形工艺却非常适合生产波形炉胆 ,可以明显提高产品质量和生产效率。  相似文献   
566.
岩石的磁化率各向异性参数(A.M.S.),在地质科学研究中的应用已受到越来越多的重视。目前测量A.M.S.的仪器主要有旋转磁力仪和卡帕桥。结合笔者的实践,本文比较详细地介绍这两类仪器用于进行各向异性测量的原理以及数据处理方法。  相似文献   
567.
水产品加工废水生物处理现状与展望   总被引:1,自引:0,他引:1  
介绍了几种较为典型的水产品加工废水生物处理工艺,以及利用生物处理工艺处理高含盐量废水实验室研究结果;展望了水产品加工废水处理技术的发展前景。  相似文献   
568.
以形状相对简单的单工序锻件为研究对象,以同时获得材料消耗最小和变形程度最均匀的终锻件为优化目标,对锻造过程毛坯形状进行多目标优化设计的研究。给出了单工序锻件形状优化设计的总的目标函数及其各子目标函数的表示方法及计算表达式,以毛坯的高径(宽)比作为优化设计的变量,基于刚粘塑性有限元理论,采用黄金分割法进行优化迭代,编制了相应的程序,并对一典型的轴对称H型锻件的毛坯形状进行了多目标的优化设计,取得了明显的效果。  相似文献   
569.
对水解(酸化)反应器处理水产品加工废水进行了试验研究,研究结果表明,在水温为20℃左右、进水COD为1100mg/L左右、水力停留时间大于2h的条件下,无需曝气作用,水解(酸化)反应器对水产品加工废水中COD的去除率大于40%。水产品加工废水具有较好的可生化性,水解(酸化)反应器对该废水可生化性能的改善作用不明显。利用Eckenfelder生物滤池数学模式对水解(酸化)反应器进行了分析,得到了水解(酸化)反应器处理水产品加工废水的生物处理动力学方程:Sc/SD=e^-0.23D/L^0.24。  相似文献   
570.
白银深加工产品及其产业化过程   总被引:1,自引:0,他引:1  
贵金属深加工可以分为广义深加工和狭义深加工。白银是最廉价和用量最大的贵金属 ,通过一系列的深加工制成一定的产品后在工业上有极为广泛的用途 ,这些使用领域也正是白银再生资源的分布所在。对白银深加工产品的用途及其产业化过程进行了探讨 ,提出了一套适合中小企业生产的产业化方案  相似文献   
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