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41.
诱导喷嘴改进滤筒脉冲清灰效果的实验研究 总被引:3,自引:2,他引:1
改善清灰效果是提高滤筒除尘效率的关键和难点问题。运用自制脉冲喷吹实验台,采用诱导喷嘴(超音速引流喷嘴和气流散射器)对325 mm×660 mm滤筒进行脉冲喷吹清灰实验研究,并与采用普通喷吹孔的实验结果进行比较分析,得出采用诱导喷嘴时侧壁正压力峰值平均值是普通喷吹孔的1.465倍;且采用诱导喷嘴时各测点的不均衡系数为0.768~1.336,普通喷口为0.270~2.251,而不均衡系数越接近于1,其清灰效果越好;同时,采用诱导喷嘴时各测点基本在同一时刻达到正峰值。实验充分表明采用诱导喷嘴确保了滤筒长度方向上内壁清灰压力的均匀性,且对滤筒清灰效果有明显的改善作用。 相似文献
42.
针对固定式可燃气体检测报警器运行管理中存在的问题进行了分析,并提出整治措施. 相似文献
43.
Rosenbloom T 《Journal of Safety Research》2006,37(2):207-212
INTRODUCTION: Through spontaneous driving observations, this study sought to examine the impact of using a hands-free cell phone while driving on speed and safe gap keeping behaviors. The study also examined the association between the measure of disturbance created by using a cell phone and the driver's awareness of the disturbance. METHOD: Twenty-three male adults were observed while driving for an hour and a half each; drivers were unaware of being observed. During the session, each of the participants received a phone call, initiated by an associate of the observer. The experiment was divided into two periods during which the experimental parameters were monitored: 10 minutes during conversation on a cell phone and 10 minutes of non-conversation on a hands-free cell phone. After the experiment, the driver was questioned concerning the extent to which his/her driving was disturbed by the cell phone conversation. RESULTS: T-test for matched samples revealed that the gaps between the drivers' cars and those in front of them diminished when drivers were engaged in the cell phone conversations. Repeated measures ANOVA revealed that drivers that had short conversations did not change their speed, while drivers who were engaged in long (over 16 minutes) conversations drove faster. No effect of drivers' awareness toward cell phone-related disturbance on actual driving behavior monitored in the present study was found. 相似文献
44.
为研究半开敞空间内可燃气体爆炸过程,设计带有泄压面的气体爆炸室,并在此基础上构建一套可燃气体燃爆特性综合试验装置。运用该试验装置,研究预混塔内甲烷气体分层现象以及甲烷爆炸浓度与最小点火能之间的变化规律。甲烷分层试验结果表明:静置一段时间后,预混塔中甲烷浓度随高度的增加而增大。最小点火能试验结果显示,当甲烷的试验爆炸体积分数在10%~13%时,其浓度与点火能之间呈现比较平缓的变化关系,而当其体积分数小于10%或大于13%时,浓度稍微变化,其点火能将发生明显变化。 相似文献
45.
朱高中 《中国安全生产科学技术》2012,8(4):127-131
设计了一种基于单片机来实现的甲烷浓度检测和报警功能的系统,该检测系统以AT89S52单片机为核心,包括有电源电路、传感器采集电路、信号放大电路、红外遥控电路、声光报警电路、显示电路等功能模块组成,通过传感器采集电路采集信号,输出与甲烷浓度对应电压信号,把电压信号进行A/D转换后送入单片机,经单片机处理后驱动器显示出被测气体甲烷浓度值,若被测甲烷浓度大于报警电路预设数值,报警电路发出报警,可以及时切断供电系统,防止瓦斯爆炸事故的发生.该系统采用高精度敏感元件,集成运算放大器INA128,ADc0809,以及远距离高可靠性通信芯片,且具有高速的处理能力,是一种电路设计新颖,参数测量准确,操作方便的甲烷浓度报警监控系统,实现了数字瓦斯气体的实时监控.为实现数字化井下测控和可视化综合管理提供了切实可行的方案. 相似文献
46.
Apps are small task-orientated programs with the potential to integrate the computational and sensing capacities of smartphones with the power of cloud computing, social networking, and crowdsourcing. They have the potential to transform how humans interact with nature, cause a step change in the quantity and resolution of biodiversity data, democratize access to environmental knowledge, and reinvigorate ways of enjoying nature. To assess the extent to which this potential is being exploited in relation to nature, we conducted an automated search of the Google Play Store using 96 nature-related terms. This returned data on ~36 304 apps, of which ~6301 were nature-themed. We found that few of these fully exploit the full range of capabilities inherent in the technology and/or have successfully captured the public imagination. Such breakthroughs will only be achieved by increasing the frequency and quality of collaboration between environmental scientists, information engineers, computer scientists, and interested publics. 相似文献
47.
为研究松散煤体低温氧化及通风供氧下的渗流传热规律,研发了渗流传热试验装置。试验装置由气体加湿系统、气体加热系统、煤样反应系统、数据采集系统和安全保护系统组成;本装置可实现自动加湿、控温、自动采集数据及处理数据。为解决装置使用和运行中的安全问题,设计了断电保护、有害气体检测等措施,保障试验装置的安全、可靠。 相似文献
48.
49.
Evaluation of mercury speciation and removal through air pollution control
devices of a 190 MW boiler 总被引:1,自引:0,他引:1
Chengli Wu Yan Cao Zhongbing Dong Chinmin Cheng Hanxu Li Weiping Pan 《环境科学学报(英文版)》2010,22(2):277-282
Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction
(SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration
and operational conditions of APCDs and mercury speciation a ect mercury removal e ciently at coal-fired utilities. The Ontario
Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation
simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor
a ecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more
elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized
mercury when SCR was in service, and oxidation e ciency reached 71.0%. Therefore, oxidized mercury removal e ciency was
enhanced through a wet FGD system. In the non-ozone season, about 89.5%–96.8% of oxidized mercury was controlled, but only
54.9%–68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal e ciency was 95.9%–98.0%, and there
was a big di erence in the total mercury removal e ciencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was
evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from
0.84 to 1.08. 相似文献
50.
石化企业综合防雷技术探讨 总被引:1,自引:0,他引:1
戴颂文 《安全.健康和环境》2009,9(9):15-17
分析了石化企业当前防雷工程中存在的问题,结合先进的防雷技术与产品,对防雷接地系统与接地、工程电子信号系统的防护提出一些改进意见。 相似文献