往复活塞式压缩机活塞杆温度高故障分析及改造

针对2台2D40型空气压缩机在实际试机过程中,活塞杆温度过高,导致连锁报警,压缩机不能正常工作的问题进行了详细的故障原因分析;对压缩机技术性能参数进行介绍;对压缩机的损伤情况进行说明并找到改造方案,解决机组运行中活塞杆温度过高的问题,从而提高机组的运行效率,使机组运行安全、稳定。     

象山隧道液压凿岩台车开挖斜孔掏槽施工技术

新建的龙岩至厦门单线铁路象山隧道断面比较小,使用液压凿岩台车开挖,斜孔掏槽方案受到很大限制。本文介绍了使用液压凿岩台车钻爆开挖象山隧道,选择斜孔掏槽方案实现快速开挖,为类似的隧道工程施工提供经验。     

水压爆破拆除钢筋混凝土隐蔽部

水压爆破是一种控制爆破技术，它可在不动用机械设备情况下，用水作为介质，把炸药的爆炸能传递给待拆构筑物，达到破碎的目的。本文介绍采用水压爆破拆除钢筋混凝土工事的设计与实施，爆破取得圆满成功。     

Development of high pressure membraneless alkaline electrolyzer

A technology for cyclic generation of hydrogen and oxygen using electrodes made of variable valency material that does not need the use of separating ion-exchange membranes is presented. The technological solution enables to fabricate electrolyzers for uninterrupted producing high-pressure hydrogen with reduced energy intensity of the production. The total work for compressing 1 m³ of hydrogen and 0.5 m³ of oxygen has been estimated. Results of investigation of influence of discrete supply of DC current to the electrolysis cell, in order to improve the processes of gas evolution and to simplify the power systems of the electrolysis plant, have been considered. There is also considered an electrolysis installation equipped with a thermosorption compressor in which LaNi₅ is used as a hydride-forming compound. The comparative characteristics of the developed electrolyzer and the currently used hydrogen generators are given.     

Influence of bio-clogging on permeability characteristics of soil

It is necessary to enhance the barrier performance of cutoff walls in order to improve the contamination control level, especially for reconstruction or expansion of existing landfill sites. This paper presents a comprehensive laboratory investigation on the synergistic effects of microorganisms and fibers on the hydraulic conductivity of silty sand to evaluate the applicability to the field condition as an alterative barrier material. Inside the soil, the added carbon fibers not only provided good biocompatibility, but also formed spatial three-dimensional network between soil particles to improve the bacterial adhesion that eventually caused 2–3 orders of magnitude decrease in soil permeability. The resistance of the biofilm to extreme conditions was tested by permeation with solutions of different salinity and pH values, and by subjecting specimens to various hydraulic gradients and soil conditions. Despite the microbial growth inhibition occurred at these conditions, however, biofilm can largely remain intact and continue to reduce k, which due to the gradual adaptation of microorganisms to the extreme environment and the gradual recovery of their activity. Results of these tests demonstrate that biofilm treatment may be a feasible technology for creating waste containment barriers in soil.     

A new experimental simulation method for the development of non-renewable hydrogen energy—Oil and gas resources

At present, the proportion of tight oil in non-renewable hydrogen energy is increasing. According to an initial exploration and attemptable practice on the exploration of tight oil, it is found that the cost can be controlled effectively and positive effects are achieved. But this technique cannot make sure the proppants filled uniformly in the long fracture. Several researches on the proppants migration experiment devices and factors influencing on proppant setting are reviewed and a new set of experimental device to simulate the laws of proppants setting in long fracture is developed. This device can simulate the main factors influencing proppants setting performance. It analyzes several factors such as wall filtration, construction displacement, sand concentration, proppant size and density, viscosity of fracturing fluid is used to rank the influencing degree of every factor. Considering the effects of mutual interference between proppants, width of fracture, rough fracture surface and fracture surface filtration during the proppants setting progress, the mathematical model of proppant setting is modified by adding sand concentration correction factor, wall effect correction factor and filtration correction factor. The experimental data verify the accuracy of the settlement model is established using the data getting from experiment.     

Effect of hydraulic retention time on a continuous biohydrogen production in a packed bed biofilm reactor with recirculation flow of the liquid phase

The present paper reports on results obtained from experiments carried out in a laboratory-scale anaerobic packed bed biofilm reactor (APBR), with recirculation of the liquid phase, for continuously biohydrogen production via dark fermentation. The reactor was filled with Kaldnes^® biofilm carrier and inoculated with an anaerobic mesophilic sludge from a urban wastewater treatment plant (WWTP). The APBR was operated at a temperature of 37 °C, without pH buffering. The effect of theoretical hydraulic retention time (HRT) from 1 to 5 h on hydrogen yield (HY), hydrogen production rate (HPR), substrate conversion and metabolic pathways was investigated. This study indicates the possibility of enhancing hydrogen production by using APBR with recirculation flow. Among respondents values of HRT the highest average values of HY (2.35 mol H₂/mol substrate) and HPR (0.085 L h^?1L^?1) have been obtained at HRT equal to 2 h.     

聚醚型合成压缩机油的研制

使用聚醚基础油，通过对抗氧剂、极压抗磨剂、助溶剂和防锈剂等添加剂的筛选及性能考察，研制了一种聚醚型合成压缩机油。该产品黏度指数达到210以上，旋转氧弹时间超过1 000 min ，铜片腐蚀（100 ℃，3h）为1b级，四球试验的钢球磨斑直径为0.5 mm左右，具有优异的黏温性能、氧化安定性、防锈抗腐性和良好的极压抗磨性，达到国外同类油品质量水平。经过一年的实际使用，油品磨损金属质量分数低于30 μg/g，表明研制产品能够满足烃类气体压缩机的润滑要求。