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941.
脉冲供能集烟气除尘和脱硫脱硝为一体的机理 总被引:9,自引:0,他引:9
本文研究脉冲电晕对SO2、NO和粉尘脱除规律以及烟气成份在脱除过程中的相互影响,在此基础上对脉冲供能脱硫脱硝和除尘的机理进行分析,肯定了在传统静电除尘器中集烟气除尘和脱硫脱硝为一体的可能性,并提出了实现方式. 相似文献
942.
943.
Deploying heating technologies, such as air-source heat pumps (ASHPs), can respond to the dual challenges of tackling fuel poverty and reducing carbon emissions from domestic energy consumption. In the UK, ASHP performance has been found to be below design levels. Elements of three strands of literature – innovation diffusion, environmental psychology and neighbourhood effects – are combined to gain insights into why the adoption and performance of ASHPs are lagging policy targets and design potential. Evidence from users, installers and area-based scheme facilitators suggests that the perceived complexity of the technology is a barrier. The level of technology maturity and the typical profile of the elderly fuel poor do not match; the target group might prefer to be late adopters or laggards in adopting technology. The role of installers is critical as the disruption from installation is a barrier to adoption and ASHPs place demands on users to change existing practices. 相似文献
944.
S.M. Asadzadeh A. Azadeh A. Negahban A. Sotoudeh 《Journal of Loss Prevention in the Process Industries》2013,26(6):1015-1026
This study analyzes and assesses the integrated health, safety, environment (HSE) and ergonomics (HSEE) factors by fuzzy cognitive maps (FCM) approach. This is achieved through integrating ergonomic and macro-ergonomic as well as occupational health and safety arrangements in an integrated modeling for assessment of their multi-faceted impact on workers' productivity, injury rate and satisfaction. This paper uses FCM to assess the direct and indirect effects of HSEE factors on system performance indicators. The results of FCM are used to develop leading indicators useful for proactive management of productivity, injury rate, and job satisfaction. The result of a comprehensive survey of 37 experts in control rooms and maintenance activities in a large gas refinery is used to show the applicability and usefulness of FCM approach. Moreover, FCM results are used to determine the causal structure of HSEE factors and system performance indicators. It is concluded that macro-ergonomics factors such as instructions and education, familiarity with organization's rules, and proper communications most contribute to improve workers' safety, satisfaction, and productivity. 相似文献
945.
Z.R. Wang M.Y. Pan J.C. Jiang 《Journal of Loss Prevention in the Process Industries》2013,26(6):1094-1099
Gas explosion in connected vessels usually leads to high pressure and high rate of pressure increase which the vessels and pipes can not tolerate. Severe human casualties and property losses may occur due to the variation characteristics of gas explosion pressure in connected vessels. To determine gas explosion strength, an experimental testing system for methane and air mixture explosion in a single vessel, in a single vessel connected a pipe and in connected vessels has been set up. The experiment apparatus consisted of two spherical vessels of 350 mm and 600 mm in diameter, three connecting pipes of 89 mm in diameter and 6 m in length. First, the results of gas explosion pressure in a single vessel and connected vessels were compared and analyzed. And then the development of gas explosion, its changing characteristics and relevant influencing factors were analyzed. When gas explosion occurs in a single vessel, the maximum explosion pressure and pressure growth rate with ignition at the center of a spherical vessel are higher than those with ignition on the inner-wall of the vessel. In conclusion, besides ignition source on the inner wall, the ignition source at the center of the vessels must be avoided to reduce the damage level. When the gas mixture is ignited in the large vessel, the maximum explosion pressure and explosion pressure rising rate in the small vessel raise. And the maximum explosion pressure and pressure rising rate in connected vessels are higher than those in the single containment vessel. So whenever possible, some isolation techniques, such as fast-acting valves, rotary valves, etc., might be applied to reduce explosion strength in the integrated system. However, when the gas mixture is ignited in the small vessel, the maximum explosion pressures in the large vessel and in the small vessel both decrease. Moreover, the explosion pressure is lower than that in the single vessel. When gas explosion happens in a single vessel connected to a pipe, the maximum explosion pressure occurs at the end of the pipe if the gas mixture is ignited in the spherical vessel. Therefore, installing a pipe into the system can reduce the maximum explosion pressure, but it also causes the explosion pressure growth rate to increase. 相似文献
946.
Peili Zhang Yang Du Yi Zhou Sheng Qi Songlin Wu Jiafeng Xu 《Journal of Loss Prevention in the Process Industries》2013,26(6):1279-1284
In order to investigate the effects of branch tunnels on explosion propagation, experiments were performed in five different configuration tunnels (straight configuration and configurations with 1 branch, 2 branches, 3 branches and 4 branches). Pressure and flame transducers were used to record the history of the pressure development and track the velocity of the flame front. It was shown that the branch tunnels had ability to enhance the maximum overpressure, rate of overpressure rise, and deflagration index (KG) of the gasoline–air mixture explosion due to the turbulence induced by the branch tunnels. The overpressure rise rate and KG of the explosion increased as a function of the number of branch tunnels. Experiments also showed that the maximum flame speed increased as the branch number increasing from 0 to 3 due to the enlargement of turbulence induced by the branch tunnels. However, an increase of branch number did not always lead to an enhancement of flame speed because the heat loss was intensified resulting from the increase of flame surface caused by the branch tunnels. When the number of branch tunnels exceeded 3, the maximum flame speed dropped. 相似文献
947.
948.
Nemitz E. Flynn M. Williams P. I. Milford C. Theobald M. R. Blatter A. Gallagher M. W. Sutton M. A. 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):189-202
A continuous relaxed eddy accumulation system ispresented for the automated measurement of surface/atmosphere exchange fluxes of atmospheric ammonia (NH3) at a single height. The new system features sampling by parallel plate denuder inlets, online chemical analysis using the conductivity cell of a commercially available NH3 analyzer and online flux calculation. The effective detection limit of the system for air concentrations is 0.2 g m-3 and it is estimated to resolve fluxes > ± 20 ng m-2 s-1, depending on the NH3 concentration and turbulence. The performance of the system was tested in two measurement campaigns above agricultural grassland, in which it was compared with a 3-point continuous gradient system. During the first campaign, after urea application of 47 kg N ha-1 in autumn, the REA system derived fluxes which were on average twice as large as the gradient fluxes, while concentrations agreed closely (on average within 4%). Possible reasons include differences in the footprint and an over-correction of the gradient flux in stable conditions. Due to wet and cold conditions, only 0.3% of the fertilizer N was volatilized as NH3 during the first week. Results from the deployment of an improved system are presented for a summer day, 6 days after fertilization with calcium ammonium nitrate. The agreement of both concentrations (on average within 13%) and fluxes (26%) was very encouraging and similar to the agreement found between two state-of-the-art gradient systems with online analysis. 相似文献
949.
Perthen-Palmisano B Jakl T 《Environmental science and pollution research international》2005,12(1):49-53
- Sustainable chemistry - Section editors:
Klaus Günter Steinhäuser, Steffi Richter, Petra Greiner, Jutta Penning, Michael AngrickBackground, Aim and Scope Chemicals play a vital role in the day-to-day life of industrialised societies. Their use is not restricted to the chemical enterprises per se, but is a crucial part of production processes in a lot of industrial sectors. Traditional instruments of environmental policy (such as bans, restrictions) can only deal with the most hazardous substances. The Johannesburg Implementation Plan of 2002 calls for more sustainable patterns of production and consumption, and sets the year of 2020 as a goal to use chemicals in a way that human health and the environment are not endangered. Political instruments should not only gather more knowledge about the properties of chemicals, but should also stimulate the environmentally sound use of chemicals. Existing business models should therefore be reviewed in relation to this strategic approach to encourage marketing options with respect to the environmental focus.Main Features Business models were examined for their effects on the consumption of chemicals and amount of waste emissions in relation to their economic potential. Different possibilities for cooperation of supplier, user and disposal companies were elaborated and examined with a view to the specific situation in Austria.Results and Discussion A range of cooperative models summarised under the term ‘chemical leasing’ - was identified, which can contribute to a more efficient use of resources. 12 main possible application areas (cleaning, lubrication, paint stripping and others) have been identified in Austria. If chemical leasing models were applied in these areas, the amounts of chemicals currently used could be reduced by one third (53,000 tonnes per year). Cost reductions of up to 15 % can be expected.Conclusion The application of chemical leasing models can contribute considerably to achieving more sustainable and resource-efficient patterns of production. The Austrian Ministry for Environment has therefore decided to subsidise the further practical implementation of these new service-oriented business models. Pilot projects in 4 enterprises, which are supervised by consulting companies, are currently being carried out. Recommendation and Outlook The experiences of the pilot projects will serve as valuable building blocks for the wider use of chemical leasing models. Furthermore, the UNIDO Cleaner Production Centres have expressed their clear interest and will examine the possibility to use chemical leasing as a part of their Cleaner Production Programmes. 相似文献
950.
危险化学品泄漏扩散研究探讨 总被引:5,自引:2,他引:5
对危险化学品泄漏扩散的研究是事故应急救援的基础。针对近年来日益增多的危险化学品泄漏事故,本文从数学模型和计算机仿真模拟两方面系统评述了国内外危险化学品泄漏扩散方面的研究,其中数学模型研究主要分为“反求源强”模型和扩散模型两类,计算机仿真模拟主要分为静态离线仿真模拟和实时动态仿真模拟两类。在此基础上,提出了进一步研究的一般框架和研究的方向。 相似文献