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排序方式: 共有1249条查询结果,搜索用时 15 毫秒
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在浅埋短隧道洞室群隧道洞门施工中受场地狭小限制等条件不利于定型钢模衬砌台车施作洞门拱墙时,采用满堂脚手架与钢拱架上铺定型组合弧形钢模配合衬砌台车整体一次性施工隧道洞门拱墙,可以解决定型钢模衬砌台车的模板庞大笨重、安拆吊装设备的场地狭小受限,以及模板拆装倒运周转成本费用较大等问题,从而满足设计要求并达到施工质量要求。 相似文献
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介绍甲岩水电站右岸泄洪洞旋流竖井在Ⅱ期开挖、支护施工阶段可选用几种施工方案。通过对几种施工方案的可行性、经济性比较,选择了从竖井上部用电动单梁起重机悬挂渣斗出渣、起吊施工材料设备的方案,在施工过程中起重机运行良好,用107 d完成右岸泄洪洞Ⅱ期开挖支护施工,比原计划提前了15 d。 相似文献
25.
随着混凝土大坝对温控要求的越来越高,大坝大体积混凝土浇筑内部埋设通水冷却管,这就要求大坝混凝土冷却水必需采取人工制冷水,才能达到设计通水温度的要求。冷水机组的运用在混凝土大坝的施工中将越来越普遍。 相似文献
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在水利水电工程激烈的竞争中,能够中标工程项目的企业,大都是以较低的工程报价和企业自身的优良技术和良好信誉的结果。施工企业要在较低的投标价的施工中如何获得利润,合同的严格管理和施工成本的有效控制是最根本的管理手段。 相似文献
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“安全第一”是一个永恒的主题,安全就是效益。安全技术措施的实施和执行,是首先在技术上保障施工安全的前提和基础,加强安全技术措施的交底、实施和过程控制,为工程施工安全与工程安全提供基础性保障作用,使安全技术工作更加规范化、标准化、系统化,并服务于安全生产,消除安全隐患,杜绝安全事故,更好的为企业创造绩效,必将成为施工企业安全生产管理的必由之路。 相似文献
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This study examines mechanisms for removal of bacteriophages (MS2 and phiX174) by ceramic membranes without application of flocculants. The ceramic membranes considered included ultra- and microfiltration membranes of different materials. Phages were spiked into the feed water in pilot scale tests in a waterworks. The membranes with pore sizes of 10 nm provided a 2.5-4.0 log removal of the phages. For pore sizes of 50 nm, the log removal dropped to 0.96-1.8. The membrane with a pore size of 200 nm did not remove phages. So, the removal of both MS2- and phiX174-phages depended on the pore size of the membranes. But apart from pore size also other factors influence the removal of phages. Removal was 0.5-0.9 log higher for MS2-phages compared with phiX174-phages. Size exclusion seems to be the major but not the only mechanism which influences the efficiency of phage removal by ceramic membranes. 相似文献
29.
Case study on the implementation of deammonification for the process water treatment of Munich WWTPs
The two-staged WWTP 'Gut Grosslappen' has a capacity of 2 mio. PE. It comprises a pre-denitrification in the first stage using recirculation from the nitrifying second stage. A residual post-denitrification in a downstream sand filter is required in order to achieve the effluent standards. Presently the process water from sludge digestion is treated separately by nitrification/denitrification. Due to necessary reconstruction of the biological stages, the process water treatment was included in the future overall process concept of the WWTP. A case study was conducted comparing the processes nitritation/denitrititation and deammonification with nitrification/denitrification including their effect on the operational costs of the planned main flow treatment. Besides the different operating costs the investment costs required for the process water treatment played a significant role. Six cases for the process water treatment were compared. As a result, in Munich deammonification can only be recommended for long-term future developments, due to the high investment costs, compared with the nitritation/denitritation alternative realizable in existing tanks. The savings concerning aeration, sludge disposal and chemicals were not sufficient to compensate for the additional investment costs. Due to the specific circumstances in Munich, for the time being the use of existing tanks for nitritation/denitritation proved to be most economical. 相似文献
30.
Lizarralde I Claeys F Ordó?ez R de Gracia M Sancho L Grau P 《Water science and technology》2012,65(11):1929-1938
The increasing costs associated with water supply and the disposal of wastewater has stimulated industries to seek more efficient water management systems. Mathematical modelling and simulation can be a very valuable tool for the study of the multiple alternatives available whilst assessing optimum solutions for water management in industry. This study introduces a new steady state model library able to reproduce industrial water circuits. It has been implemented in a novel software framework for the representation, simulation and optimization of industrial water networks. A water circuit representing a paper mill has been modelled and simulated showing the capability to reproduce real case studies. Alternative scenarios for the water network have also been tested to assess the capability of the models to optimize water circuits minimizing total cost. 相似文献