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901.
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。 相似文献
902.
Tshering Pelden Chongdee Thammaknet Panote Thavarungkul 《Journal of environmental science and health. Part. B》2013,48(7):480-490
An innovative, cost-effective, simple, and environmental friendly tea bag filter paper protected micro-solid phase extraction (μ-SPE) technique was developed for the first time with the aim to miniaturize and minimize the use of organic solvents for the extraction and determination of butachlor in aqueous samples. The μ-SPE device was produced by packing 3.0 mg of an easily synthesized new sorbent, hydroxyl-functionalized polypyrrole (OH-PPY), inside a small tea bag filter paper sachet (1.0 cm × 0.5 cm) that served as a protective envelope. Both the extraction and desorption procedures were facilitated by sonication. Due to the high porosity and the fast water absorption of the tea bag filter paper, the analyte could easily diffuse through and enhance the interaction with the sorbent. Under the optimized conditions for the GC-ECD and the μ-SPE, the limit of detection (S/N ≥ 3) was 2.0 μg L?1 while the limit of quantitation (S/N ≥ 10) was 10.0 μg L?1. The recoveries of the butachlor spiked at 0.050, 0.10, and 0.50 μg mL?1 ranged from 77.9 ± 3.0 to 112.5 ± 2.9%. The proposed method was successfully applied for the determination of butachlor in water samples from paddy cultivation sites. The levels found were from non-detectable to 24.71 ± 0.37 μg L?1. 相似文献
903.
904.
反吹风袋式除尘器存在运行阻力高、滤袋寿命短、排放浓度高等缺点.论述了利用改进滤筒、增设导流装置等一系列技术措施,提高滤筒式除尘器技术性能,从而用滤筒除尘技术对反吹风除尘器进行改造达到节能减排的效果. 相似文献
905.
906.
During two campaigns in winter 2004, size segregated impactor samples (0.1-10 microm) and filter samples were taken in two Central European cities (Vienna, Austria and Ljubljana, Slovenia). The impactor samples were analyzed for major inorganic ions and short-chain organic acids, total carbon (TC) and black carbon (BC). Maximum concentrations of total mass were 71.6 microg m(-3) in Vienna and 73.1 microg m(-3) in Ljubljana. Minimum concentrations in Vienna were only half those in Ljubljana. The BC content of the aerosol was similar (ca. 8%), but the BC/TC ratio was higher in Vienna than in Ljubljana (0.39 vs. 0.29), reflecting the different contribution of diesel traffic emissions. The mass median diameters of the submicron size distributions of all major fractions (total mass, TC, BC and SO(4)(2-)) were smaller in Vienna (0.43 microm, 0.41 microm, 0.38 microm and 0.48 microm, respectively) than in Ljubljana (0.55 microm, 0.44 microm, 0.42 microm and 0.60 microm, respectively). Impactor/filter ratios for total mass were 0.79 in Vienna and 0.82 in Ljubljana, while the ratios for BC were 0.56 in Vienna and 0.49 in Ljubljana. An estimation of the mixing state of accumulation mode BC indicated that 33% and 37% of BC, respectively, are mixed externally to the aerosol in the accumulation size range in Vienna and Ljubljana. 相似文献
907.
908.
离子色谱法测定大气颗粒物中的阴离子 总被引:4,自引:0,他引:4
用戴安DX—120型离子色谱仪测定大气颗粒物中的阴离子,并对其分析过程进行研究。 相似文献
909.
为有效控制矿用移动式救生舱内气体浓度,确保救生舱内环境质量,保障舱内人员生命安全;根据《煤矿井下紧急避险系统建设管理暂行规定》的指标要求,采用扩展卡尔曼滤波方法对救生舱舱内气体参数的变化过程进行辨识,得出舱内气体浓度的状态空间模型,并应用迭代优化控制方法对气体浓度进行控制调节;在矿用救生舱模型和现场样机中分别进行了模拟和现场试验。结果表明,测控系统能有效控制救生舱舱内气体浓度进行,满足各项指标要求,且具有较好的鲁棒性。 相似文献
910.