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排序方式: 共有479条查询结果,搜索用时 15 毫秒
1.
本文阐述了充分考虑矿石性质,探索出混合浮选的分步流程,恰当的施用多元扑收剂所产出的“协同效应”,稳定和强化选别工艺,收到提高选金技术指标的效果。 相似文献
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Lourdes García-Rodríguez Ana I. Palmero-MarreroCarlos Gómez-Camacho 《Desalination》2002,142(2):135-142
This paper deals with a global analysis of the use of solar energy in seawater distillation under Spanish climatic conditions. Static solar technologies as well as one-axis sun tracking were compared. Different temperature ranges of the thermal energy supply required for a desalination process were considered. At each temperature range, suitable solar collectors were compared in some aspects as: (1) fresh water production from a given desalination plant; (2) attainable fresh water production if a heat pump is coupled to the solar desalination system; (3) area of solar collector required for equivalent energy production. Results showed that direct steam generation (DSG) parabolic troughs are a promising technology for solar-assisted seawater desalination. 相似文献
4.
为解决传统温室大棚在保温和降湿方面存在的问题,扩大太阳能热气流发电应用范围,本文提出一种基于温室大棚的双层集热棚式太阳能热气流发电装置。给出了夏冬两季不同运行模式,同时对双层集热棚采光性进行计算和分析,结果表明,主集热棚内平均单位面积的太阳净辐射量为599.76W/m2,次集热棚内平均单位面积的太阳净辐射量为539.784W/m2,双层集热棚平均透光率为69.2%,符合国标规定的温室大棚光照要求,满足大棚夏季降温、降湿,冬季保温、降湿的要求,本研究可以实现太阳能发电和改善温室大棚作物的生长环境,具有一定的推广应用价值。 相似文献
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《Ergonomics》2012,55(10):2056-2064
The energetic load and guidelines were formulated for energetic load in three methods of refuse collecting. These methods were collecting refuse in polythene bags (in a city area and in a suburb), in two-wheeled mini-containers and in large four-wheeled containers. To determine the energetic load of the collecting methods, these collecting methods were simulated in the laboratory. The simulation protocols were based on data such as weight of the handled materials, and the frequency and duration of the most prominent refuse collecting activities as found in the preliminary field study. During the execution of the protocols the heart rate and oxygen uptake were continuously recorded. The maximal oxygen uptake was determined during a continuous running protocol on a treadmill. The energetic load was expressed in terms of percentage of the maximal oxygen uptake. As the limit for the energetic load a value of 30% of the maximal oxygen uptake during an 8-h working day was chosen. The limit for energetic overload was exceeded for the maximal oxygen uptake for refuse collecting with polythene bags in a city area (44·5%), collecting with bags in a suburb (37·2%) and with mini-containers. The percentage of the maximal oxygen uptake for collecting with large containers was 28·4%, which was below the limit for the energetic load of 30%. Guidelines were formulated for the relevant occupational field terms: maximal amount of collecting hours and maximal amount of collected refuse per collector per hour. The guidelines were formulated in percentiles (P90 and P75). This means that 90 and 75% of the refuse collecting population in The Netherlands will be prevented from having an energetic overload above the limit of 30% of the maximal oxygen uptake. 相似文献
6.
K. Channa R. De SilvaBrian J. Kaseman David J. Bayless 《International Journal of Hydrogen Energy》2011,36(1):779-786
Planar electrolyte supported solid oxide fuel cells were operated at 900 °C with humidified H2 for 200 h using silver mesh and paste for cathode current collection. Continuous potentiostatic tests at 0.7 V appeared to induce migration of Ag towards electrode-electrolyte interphase, while continuous OCV tests caused no mass transport. Similar SOFCs fueled by coal syngas at 850 °C using Ag for both anode and cathode current collection indicated little, if any, Ag migration; providing the possibility of employing Ag for 100 h laboratory scale tests using coal-derived syngas. Use of high temperature steam, carbon dioxide and carbon monoxide did not result in the formation of silver carbonates. 相似文献
7.
采用M16,M17强化铜,金,银回收的研究 总被引:1,自引:1,他引:1
新型捕收剂M16、M17用于凤凰山铜矿提高铜、金、银的回收率,取得了突出效果。该药剂对硫化铜矿物的选择性捕收效果好,而且对伴生金、银有较强的捕收能力。产品稳定性好,使用方便,生产过程稳定,具有较高的推广应用价值。 相似文献
8.
The temperature requirements of solar industrial process heat applications range from 60 °C to 260 °C. The characteristics of medium to medium-high temperature solar collectors are given and an overview of efficiency and cost of existing technologies is presented. Five collector types have been considered in this study varying from the simple stationary flat-plate to movable parabolic trough ones. Based on TRNSYS simulations, an estimation of the system efficiency of solar process heat plants operating in the Mediterranean climate are given for the different collector technologies. The annual energy gains of such systems are from 550 to 1100 kWh/m2 a. The resulting energy costs obtained for solar heat are from 0.015 to 0.028 C£/kWh depending on the collector type applied. The viabilities of the systems depend on their initial cost and the fuel price. None of these costs however is stable but change continuously depending on international market trends and oil production rates. The costs will turn out to be more favourable when the solar collectors become cheaper and subsidisation of fuel is removed. Therefore the optimisation procedure suggested in this paper should be followed in order to select the most appropriate system in each case. 相似文献
9.
《Journal of Building Performance Simulation》2013,6(3):149-162
Using solar thermal energy is an interesting option for heat-driven air conditioning, e.g. desiccant cooling. In this article, the autonomous operations of a solar desiccant cooling plant powered by direct-flow vacuum-tube collectors are investigated. A model of the solar installation and the desiccant air handling unit is presented and implemented in the SPARK simulation environment and then it is validated experimentally. The overall cooling efficiency of the system is evaluated using simulation for humid and moderately humid climates and the effect of increasing the regeneration temperature on the cooling capacity, the overall cooling efficiency is studied and finally the overall efficiency of the collectors is calculated for the studied cases. 相似文献
10.
The technology of brazing the absorber of planar solar heating collectors, consisting of a ray-receiving panel, produced from copper sheets with a composite selective coating and a tubular part, produced from L63 brass, is examined. The design of the absorber developed by the authors is described. The requirements on brazing technology to preserve the selective multilayer coating during heating of the Sun ray collector panel are determined. The experimental results are used for selecting the brazing alloys, fluxes and temperature–time parameters used in the development of the industrial technology of brazing the Sun ray collector panel of the absorber. 相似文献