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151.
Michael Adam Steve Comfort Daniel Snow David Cassada Matthew Morley Wilson Clayton 《Canadian Metallurgical Quarterly》2006,132(12):1580-1588
Years of wastewater discharge at the Department of Energy’s Pantex Plant have contaminated the vadose zone and underlying perched aquifer with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Because the vadose zone is acting as a continual source of groundwater contamination, removing RDX from the unsaturated zone is paramount to prevent further contamination. We determined the efficacy of ozone to degrade and mineralize RDX. Solution experiments showed that ozone (27?mg?L?1; 150?mL?min?1) was effective in mineralizing 80% of the RDX (30?mg?RDX?L?1) provided that some Pantex soil was present to buffer the solution pH. Soil columns treated with ozone produced 50% RDX mineralization within 1 day and >80% within 7 day. Experiments designed to evaluate aerobic biodegradation following partial ozonation of a RDX solution showed that ozone-generated RDX products were much more biodegradable than untreated controls in aerobic microcosms (35 versus <0.3% cumulative mineralization). These results support the use of ozone as a remedial treatment for the contaminated vadose zone at the Pantex facility. 相似文献
152.
连续蒸煮器内洗涤结合器外扩散洗涤,具有洗涤时间长、洗涤效率高、提取黑液浓度高、浆层厚度均匀、浆层结构组织和浓度一致等特点,运行可靠,易于自动化控制,实现了洗涤用水的封闭循环。 相似文献
153.
In an industrial plant, the level of maintenance provided to individual equipment is directly related to the availability that is expected from it. Thus, it is hoped that the most critical equipments will not fail or, at least, that any failure will be rapidly detected and corrected in the minimum time possible. Since resources are limited, it is necessary to determine how they should be distributed, so that no important equipment remains neglected while more resources are concentrated on the most critical items. Therefore, it is necessary to classify equipment in an objective way according to its importance. The method of multicriterion classification of critical equipments (MCCE)2, which is described in the present work, allows systematic and detailed quantification of the criticality of all equipment, that is to say, it provides an evaluation of the importance that its correct operation has for the plant. To provide this information, the consequences for a company of any failure in the equipment concerned are analysed. Finally, a real case example of an urban wastewater treatment plant is described, in which the MCCE method is applied. 相似文献
154.
基于数字运算的PSD调理电路设计 总被引:2,自引:0,他引:2
介绍了基于数字运算的PSD调理电路思想及具体线路构造,该电路避免了模拟运算的缺陷,提高了精度和可靠性. 相似文献
155.
较系统地介绍了我国第1条国产化的中宽带钢冷连轧生产线,即唐山建龙钢铁控股有限公司900mm冷连轧生产线的工艺流程、主要设备组成及技术特点。重点介绍了900mm 4机架六辊轧机的技术参数、性能特点及自动控制系统。该生产线投产以来,取得了较好效果。 相似文献
156.
157.
从传统意义上来讲,针织物及对张力敏感的梭织物的湿处理生产线(包括漂白、染色、柒色后水洗)通常是利用染缸来完成的,而这正是高水耗、高蒸汽消耗和高能源消耗的症结所在,同时带来一些质量问题(如折痕、起毛球和刮印等)。随着现代连续式平幅湿处理线技术的发展,整体生产成本可以下降到最多这50%。介绍了德国欧宝泰克生产的敏感织物连续式平幅湿处理线设备。 相似文献
158.
通过对洛阳热电厂拟选择的地基处理方案进行比较,并结合该电厂施工实例论证了φ800/1600扩底钢筋混凝土灌注桩是最适于该电厂及相似地区的地基处理方式。 相似文献
159.
This paper presents a coordinated reverse logistics (CRL) management system for the treatment of multi-source hazardous wastes in a given region, in this case, a specific high-technology manufacturing zone. A linear multi-objective analytical model is formulated that systematically minimizes both the total reverse logistics operating costs and corresponding risks. In addition to inter-organizational logistics operating factors, environmental concerns are considered and formulated as corresponding risk-related constraints. Using the proposed model, results of numerical studies indicate that when the aspect of risk-induced penalties is not considered, the operational costs of regional hazardous-waste management can be efficiently reduced by 58%, compared to the existing operational costs at the study site. In addition, it is also observed that the corresponding weight associated with the risk-induced objective function embedded in the proposed model seems to have a significant effect on the CRL costs. 相似文献
160.
一种有机硫类絮凝剂DTC的合成及性能评价 总被引:1,自引:0,他引:1
讨论了由有机伯胺或仲胺和CS2合成二硫代氨基甲酸盐DTC的反应及副反应,简介了合成工艺。根据红外光谱确认了由三乙烯四胺合成的二硫代氨基甲酸盐(以下简称DTC)的结构。以含原油350 mg/L、含悬浮固体55.1 mg/L,含Fe^2+10.0 mg/L的模拟污水为实验水样,考察了该DTC的絮凝性能,在40℃、pH=6-7、沉降时间30分钟条件下DTC的适宜加量为20 mg/L,此时污水含油量为9.0 mg/L;使用DTC的适宜pH范围在4-8,pH=6为最佳值,适宜温度范围为10-45℃,温度高于45℃时DTC可发生热分解;DTC的除油效果随污水中Fe^2+浓度增大而改善。在含油89.1 mg/L、含悬浮固体55.1 mg/L、含Fe^2+13.2 mg/L的油田污水中,DTC的除油率最高,远高于常用絮凝剂PFS,PAC,CPAM,HPAM和PAM。当污水中不含Fe^2+时,DTC无絮凝除油效果。讨论了DTC在Fe^2+参与下的絮凝过程。图5表1参8。 相似文献