浅析电袋除尘器滤袋的设计选型

扬子石化热电厂1～9号炉电除尘器全部改造为电袋除尘器后,出口粉尘浓度均满足排放要求。但运行中发现5、6、9号炉电袋除尘器滤袋破损较多,影响了电袋除尘器的安全稳定运行。分析了这3台炉滤袋破损的原因,提出在电除尘器改造电袋除尘器的工程实践中滤袋选型是个关键。滤袋设计时应以滤料的连续长期使用温度来选型,同时应重视设计煤种和较核煤种的选取,袋区的过滤风速以1.0～1.2m/s为宜。     

全尺寸巷/隧道火灾风烟流温度预测模型与验证

为探究巷/隧道火灾热动力灾害的演化规律,基于能量守恒定律和热量转换关系,建立巷/隧道火灾风烟流温度演化的预测模型;考虑巷道分叉和汇合对烟气蔓延和温度的影响,构建分叉和汇合巷道内烟流温度随时间变化的演化模型。通过开展全尺寸巷道火灾实验以及与国内典型隧道火灾试验数据对比,对理论模型进行验证。研究结果表明：理论模型所呈现的烟气温度随时间的变化关系,能较好地反映火灾发展的3个阶段,烟气温度的变化趋势符合火灾火源燃烧特性曲线;理论模型能够准确地预测顶棚最大烟气温升以及温度纵向衰减现象,烟气最高温度预测值与实验结果的误差率在15%以内。研究结果可为巷/隧道火灾时期的烟气控制和救援提供理论参考。     

The effect of artificial smoke compound on physiological responses,cognitive functions and work performance during firefighting activities in a smoke-diving room: an intervention study

This study investigated the combined effect of firefighting operations and exposure to smoke on physiological responses, cognitive functions and physical performance among firefighters. Each firefighter was engaged in two experimental conditions: (a) without artificial smoke, control (NS); (b) with artificial smoke (WS). The results of data analysis revealed that heart rate and body temperature increased significantly after the firefighting activities in the two conditions relative to baseline. In addition, reaction time (RT) and correct response (CR) decreased after the activity relative to baseline and there was a significant difference in RT and CR between the NS and WS conditions. There was also a significant difference in performance time between the NS and WS conditions. These findings demonstrated that a smoke compound has an insignificant effect on physiological responses during firefighting activity. On the contrary, the smoke compound has a detrimental influence on cognitive and physical performance.     

化学改性空心微珠阻燃热塑性聚氨酯弹性体的研究

为了提高热塑性聚氨酯弹性体的阻燃性,以四氟硼酸盐离子液体对空心微珠进行化学改性,获得新型阻燃热塑性聚氨酯弹性体复合材料。采用锥形量热仪和烟密度测试仪测定分析新型阻燃热塑性聚氨酯弹性体复合材料的阻燃、抑烟性能;探究化学改性后的空心微珠对热塑性聚氨酯弹性体的阻燃与抑烟效果的影响,以及不同组分含量的改性空微珠对热塑性聚氨酯弹性体的阻燃抑烟性能的影响。结果表明:采用四氟硼酸盐离子液体进行化学改性的空心微珠能够明显改善热塑性聚氨酯弹性体的阻燃性能;添加以四氟硼酸盐离子液体进行化学改性的空心微珠的热塑性聚氨酯弹性体复合材料具有一定的抑烟效果,其抑烟性能虽不如添加单一空心微珠的热塑性聚氨酯弹性体复合材料,但优于纯热塑性聚氨酯弹性体材料;相比于添加单一空心微珠的热塑性聚氨酯弹性体复合材料,添加化学改性空心微珠的热塑性聚氨酯弹性体复合材料的抑烟效果下降幅度低于阻燃效果的增强幅度,改性后的复合材料阻燃抑烟总体效果强于未改性的复合材料,改性空心微珠含量越高,总体效果越好。     

电炉除尘系统运行状况的诊断

宝钢股份公司宝钢分公司电炉除尘系统自投运以来就存在一些问题,随着产能扩容,除尘系统运行状况越来越差,需要进行改造.通过对电炉除尘系统的主要设备及排烟点的运行状况进行测试,根据测试结果分析电炉除尘系统存在的问题,提出改造建议.     

多层建筑火灾烟气运动和回燃的数值模拟研究

为了解多层建筑火灾的蔓延发展和烟气运动,应用大涡模拟(LES)方法对多层建筑火灾发生过程进行数值模拟分析,模拟不同工况下走廊和各楼层中火灾烟气运动和温度的变化情况.尤其针对内部含有竖井的多层建筑,考虑到烟囱效应对火灾发展和烟气蔓延的影响,分别设置自然排烟和机械排烟的实验工况,分析电梯间通风口在自然排烟和机械排烟状况下火灾的发展和烟气运动.通过分析温度和能见度数据,发现合理安排机械排烟能够争取更多人员逃生时间.对于多层建筑火灾中发生的回燃现象进行了原因分析.     

焦炉烟气中复杂有机污染物筛选研究(I):采样技术与方法

借鉴国内外典型烟气采样装置 ,设计出多级串联采样装置。它将多种过滤、吸附材料联合使用 ,具有一次采集有机污染物种类全 ,数量多 ,结构简单 ,操作方便 ,适用范围广等特点 ,实际采集鞍钢焦炉烟气样品 ,效果很好。     

我国主要市售香烟主流烟气中多环芳烃的分析

选取我国主要市售烤烟型和混合型两种类型卷烟共15种,采集自动吸烟机抽吸后主流烟气中的颗粒物,用GC/MS选择离子方式测定其中USEPA优先控制的16种多环芳烃(PAHs)的含量.结果表明:卷烟主流烟气中PAHs总量的范围为34.27-1603.75ng ·cig-1,且烤烟含量普遍高于混合型卷烟.主流烟气中轻组分PAHs为主,其中(2 3)环PAHs占总量的86%.苯并(a)芘浓度范围为0.79-17.88ng ·cig-1,与多环芳烃总量、致癌性多环芳烃总量、苯并(a)芘当量浓度呈现较好的正相关,因此,可以用苯并(a)芘作为主流烟气中PAHs的指标物.烤烟型卷烟中苯并(a)芘均高于混合型卷烟,但单位重量颗粒物中BaP在部分混合型卷烟中含量却高于烤烟型卷烟,可能是不同过滤嘴过滤效果不同所致.     

Atmospheric NH3 as plant nutrient: a case study with Brassica oleracea

Nutrient-sufficient and nitrate- or sulfate-deprived plants of Brassica oleracea L. were exposed to 4 microl l(-1) NH3 (2.8 mg m(-3)), and effects on biomass production and allocation, N-compounds and root morphology investigated. Nitrate-deprived plants were able to transfer to atmospheric NH3 as nitrogen source, but biomass allocation in favor of the root was not changed by exposure to NH3. NH3 reduced the difference in total root length between nitrate-sufficient and nitrate-deprived plants, and increased the specific root length in the latter. The internal N status, therefore, might be involved in controlling root length in B. oleracea. Root surface area, volume and diameter were unaffected by both nitrate deprivation and NH3 exposure. In sulfate-deprived plants an inhibitory effect of NH3 on root morphological parameters was observed. These plants, therefore, might be more susceptible to atmospheric NH3 than nitrate-deprived plants. The relevance of the present data under field conditions is discussed.     

Relative effects of elevated background ozone concentrations and peak episodes on senescence and above-ground growth in four populations of Anthoxanthum odoratum L

Four populations of Anthoxanthum odoratum from North Wales, UK, were exposed to the following combinations of mean background and peak concentrations of ozone for 12 weeks in solardomes: LL (14.3 ppb, 18.9 ppb, respectively), LH (14.8 ppb, 52.3 ppb), HL (28.9 ppb, 35.7 ppb) and HH (30.5 ppb, 72.1 ppb). Elevated ozone rapidly induced premature senescence, with effect increasing in the order: LL < LH < HL < HH. By week 11, the LH and HL treatments had induced similar amounts of whole plant senescence even though the AOT40₁₂ values (accumulated between 8am and 8pm) were very different at 10.6 ppm h and 4.1 ppm h, respectively. Overall, linear correlations between whole plant senescence were stronger for AOT0 than for AOT40. Intraspecific variation in the senescence response to the different profiles was observed after 11 weeks of exposure. Effects on growth and tillering were less pronounced than effects on senescence.