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951.
952.
全国火电厂烟气连续监测系统运行状况调研及分析 总被引:20,自引:0,他引:20
通过对全国火电厂烟气连续监测系统运行状况的实地调查和函调,发现全国已有40个火电厂安装了51套烟气连续监测系统,另有近30个火电厂已购买或正准备购买.51套中全套引进的有45套,其余6套有国内单位参与配套,共涉及中外厂家22个;安装在烟囱上的有17套,占33.3%;系统能够运行或大部分仪器设备在运行的有23套,占45.1%,但运行结果基本上均未得到环保部门认可,处于无效运行状态;绝大部分烟气连续监测系统处于停运状态,甚至从未投运过.文章分析了烟气连续监测系统运行状况不佳的原因,并提出改进建议. 相似文献
953.
Thermal behaviors and heavy metal vaporization of phosphatized tannery
sludge in incineration process 总被引:1,自引:1,他引:0
The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente... 相似文献
954.
Inderjeet Singh Daljit Singh Manpreet Singh 《International Journal of Green Energy》2019,16(6):483-489
Conventional solar photovoltaic (PV) module converts the light component of solar radiation into electrical power, and heat part is absorbed by module increasing its operating temperature. Combined PV module and heat exchanger generating both electrical and thermal powers is called as hybrid photovoltaic/thermal (PV/T) solar system. The paper presents the design of a PV/T collector, made with thin film PV technology and a spiral flow absorber, and a simulation model, developed through the system of several mathematical equations, to evaluate the performance of PV/T water collectors. The effect of various parameters on the thermal and electrical efficiency has been investigated to obtain optimum combination of parameters. Finally, a numerical simulation has been carried out for the daily and annual yield of the proposed PV/T collector, and comparison with a standard PV module is discussed. 相似文献
955.
Clinton J. Martin Clayton Hodges Randel Dymond 《Journal of the American Water Resources Association》2019,55(2):511-522
Thermal pollution is a growing concern as communities strive to protect and improve the nation's waters. The purpose of this study was to develop and analyze a geospatial model that predicts the relative risk of contribution of thermal energy to surface runoff throughout an urban watershed. A geospatial‐based solution could serve as a screening method or planning element, prior to or instead of the development of a more complex simulation of mass‐load transport of thermal energy. The study's theoretical methodology integrated the thermal potential of land cover and thermal decay due to overland travel to inlets. The resulting thermal pollution potential (TPP) index value was then assigned to individual model grid cells for comparison. Analysis of results from application to a case study watershed in Blacksburg, Virginia, indicated the computational methodology is not very sensitive to changes in spatial resolution. The thermal decay constant used in the analysis was varied, and results indicated a low sensitivity to selection of this parameter. A comparison between methods of watershed delineation also indicated use of infrastructure‐corrected watershed delineation yields better results than derivation from automated techniques. The geospatial method presented may be used to reproduce a TPP risk map to prioritize thermal pollution mitigation efforts. 相似文献
956.
Ashmore Mawire 《International Journal of Green Energy》2018,15(5):305-313
Experiments are described to investigate the thermal performance of a discharging heat exchanger for a small storage tank filled with oil. Experimental results are presented in terms of the discharging energy rates (power) and the discharging exergy rates for low (~4 ml/s) and high discharging flow rates (~8 ml/s). Water heating energy rates, which are respectively maximized at approximately 600 W and 1200 W at low and high flow-rate discharging, are found to be higher than the discharging energy rates, which are respectively maximized at 450 W and 900 W. These results indicate that the energy rates do not accurately evaluate the thermal performance of the discharging heat exchanger since the energy heating rate of the water is greater than that for the oil that heats it, which is thermodynamically inconsistent. The energy rates should thus be used with caution when the thermal performance of the heat exchanger is evaluated. Water heating exergy rates, which are respectively maximized at approximately 45 W and 130 W at low and high flow-rate discharging, are generally smaller than the discharging exergy rates, which are respectively maximized at 65 W and 170 W. Exergy rate results are thus more consistent in the physical process of water heating, and an exergy factor is suggested as a proper measure for evaluating the performance of the discharging heat exchanger. The maximum value of the exergy factor is found to increase from 0.15 at low flow rates to a maximum value of approximately 0.19 at high flow rates. This implies that to extract more energy from a storage tank to a discharging heat exchanger, the flow rate has to be high, which is consistent with the physical process of heating water faster to higher temperatures. The exergy factor can thus be used as a design parameter for discharging heat exchangers. 相似文献
957.
基于筛选测试的化工反应危害评估探讨 总被引:1,自引:0,他引:1
本文主要讨论了基于筛选测试方法的化工反应危害评价。该方法是利用DSC、TS“等差热分析仪对化学品和混合物进行热稳定性的筛选测试,根据起始温度和反应焓变对化合物危害程度分级进行分级,建立反应风险指数,从而在小试和中试阶段就将反应危害降低或消除,确保大规模生产时的安全性,为真正实现化工工艺本质安全。此外,还比较了DSC、TSU、AFFAC、RSST等热分析仪,认为TSU和RSST是目前较为合适的热筛选分析仪,为建立反应危害实验室相关仪器的选型提供了参考。 相似文献
958.
油罐扬沸火灾防治模拟实验研究 总被引:2,自引:1,他引:1
分析扬沸火灾形成的3个基本物理条件,给出扬沸三角形的概念,提出通过破坏3个基本条件中任一条件来抑制扬沸火灾发生的构想。为解决其防治问题建立小尺度油罐扬沸火灾防治模拟实验台,用沸石和双列盘管式冷却法对扬沸火灾防治进行了实验研究;通过对比两种方法施加前后的油层、油水界面、水层温度和火焰辐射,发现双列盘管式冷却法和沸石能有效地抑制扬沸的形成和降低扬沸的危害程度。从机理上分析,小尺度油罐扬沸火灾的防治方法可为扬沸火灾的防治提供一定的理论依据。 相似文献
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960.