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311.
通过对某延迟焦化装置生产过程中存在的职业病危害因素进行检测分析,找出职业病危害的关键控制点,并提出了防护措施要求。 相似文献
312.
313.
朱金秀 《环境与可持续发展》2015,(4)
本文通过改变实验室温度、显色时间、是否加入乙酸锌-乙酸钠、稀释水的酸碱性等试验条件,探讨硫化物的最佳测定条件。试验结果表明,在温度为18~22℃、稀释水p H在8~10、使用液中加入乙酸锌-乙酸钠时,采用亚甲基蓝分光光度法测定硫化物标准样品,可以得到较准确的测定结果。 相似文献
314.
Hydrogen sulfide (H2S) is an endogenous gaseous molecule, functioning as a physiological regulator. This study aimed to investigate the role of H2S in atherosclerosis. Rabbits receiving high cholesterol were given atorvastatin (10 mg/kg/day, orally) or sodium sulfide (1.1 mg/kg/day, intramuscular) 2 weeks after commencement of high-cholesterol diet and continued for 4 weeks. Serum lipid profiles, lipid peroxidation indexed as malondialdehyde, glutathione, superoxide dismutase, the vascular adhesion molecule-1, and aortic vascular endothelial growth factor were determined. Rabbits receiving a high-cholesterol diet showed elevated levels of total serum cholesterol, triglycerides, low-density lipoprotein cholesterol, malondialdehyde and vascular adhesion molecule-1, and aortic vascular endothelial growth factor expression and lower levels of high-density lipoprotein cholesterol, glutathione, and superoxide dismutase. Treatment with atorvastatin and sodium sulfide has beneficial effects on serum lipid profile, oxidative damage, vascular adhesion molecule-1, and aortic expression of vascular endothelial growth factor. 相似文献
315.
Kung-Yuh Chiang Ming-Hui Lin Cheng-Han Lu Kuang-Li Chien Yun-His Lin 《International Journal of Green Energy》2015,12(10):1005-1011
This research investigates an enhanced removal rate of tar and trace pollutants (e.g. hydrogen chloride and hydrogen sulfide, H2S) in the gasification of rice straw, using an integrated in situ tar reduction and hot-gas cleaning technique. The gasification temperature was set at 900°C and equilibrium ratio (ER) was 0.30 in the gasifier. In the in situ tar reduction method, the catalyst, dolomite with an amended ratio of 0–15% was introduced to the gasifier. The integrated hot-gas cleaning system applied a multi-packed tower to remove the tar, sulfur and/or chlorine byproduct in syngas at 250°C. The packed materials composed of zeolite, calcined dolomite and activated carbon. The experimental results indicated that the tar concentration of syngas was approximately 20 g/kg. However, in catalytic gasification with 5% dolomite addition, the tar concentration reduced to 17 g/kg. The tar reduction efficiency was approximately 15% by an in situ dolomite addition. When applying the integrated hot-gas cleanup system, the tar was virtually eliminated. The total tar elimination rate was almost 100% and the cleaned syngas could be applied in other energy utilization equipment. On the other hand, the H2S and HCl concentration were 101 ppmv and 991 ppmv, respectively. After the integrated syngas cleaning system, the H2S and HCl were decreased to 7.9 ppmv and 410 ppmv with a removal efficiency of 92.1% and 58.6%, respectively. It can be concluded that combining the in situ method with the integrated syngas cleaning system can effectively reduce the amount of byproduct and enhance the syngas quality in the gasification of rice straw. 相似文献
316.
Atmosphericmixing ratios of carbonyl sulfide (COS) in Beijingwere intensivelymeasured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximumaverage value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations (R2 > 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes (ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios. 相似文献
317.
Use of additive and pretreatment to control odors in municipal kitchen waste during aerobic composting 总被引:2,自引:0,他引:2
Jing Yuan Qingyuan Yang Zhiye Zhang Guoxue Li Wenhai Luo Difang Zhang 《环境科学学报(英文版)》2015,37(11):83-90
The effects of adding a bulking agent and chemically pretreating municipal kitchen waste before aerobic composting were studied using a laboratory-scale system. The system used 20-L reactors and each test lasted 28 days. The objective was to decrease NH3 and H2S emissions during composting. The bulking agent, dry cornstalks, was mixed with the kitchen waste to give a mixture containing 15% (wet weight) bulking agent. A combined treatment was also conducted, in which kitchen waste mixed with the bulking agent was pretreated with ferric chloride (FeCl3). Less leachate was produced by the composted kitchen waste mixed with bulking agent than by the kitchen waste alone, when the materials had reached the required maturity. The presence of cornstalks also caused less H2S to be emitted, but had little impact on the amount of NH3 emitted. The FeCl3 was found to act as an effective chemical flocculant, and its presence significantly decreased the amounts of NH3 and H2S emitted. Kitchen waste mixed with cornstalks and treated with FeCl3 emitted 42% less NH3 and 76% less H2S during composting than did pure kitchen waste. 相似文献
318.
A continuous fluidized bed bioreactor (FBBR) with nylon support particles was used to treat synthetic sulfide wastewater at different hydraulic retention time of 25, 50 and 75 min and upflow velocity of 14, 17 and 20 m/hr. The effects of upflow velocity, hydraulic retention time and reactor operation time on sulfide oxidation rate were studied using statistical model. Mixed culture obtained from the activated sludge, taken from tannery effluent treatment plant, was used as a source for microorganisms. The diameter and density of the nylon particles were 2-3 mm and 1140 kg/m3, respectively. Experiments were carried out in the reactor at a temperature of (30 ± 2)℃, at a fixed bed height of 16 cm after the formation of biofilm on the surface of support particles. Biofilm thickness reached (42 ± 3) μupm after 15 days from reactor start-up. The sulfide oxidation, sulfate and sulfur formation is examined at all hydraulic retention times and upflow velocities. The results indicated that almost 90%-92% sulfide oxidation was achieved at all hydraulic retention times. Statistical model could explain 94% of the variability and analysis of variance showed that upflow velocity and hydraulic retention time slightly affected the sulfide oxidation rate. The highest sulfide oxidation of 92% with 70% sulfur was obtained at hydraulic retention time of 75 min and upflow velocity of 14 m/hr. 相似文献
319.
本文研究了过滤式防毒面具滤毒罐防护硫化氢性能试验中,采用用碘量法和紫外光度法对硫化氢浓度测定的对比。通过试验证明了,碘量法测得的硫化氢的浓度均偏低。结果表明:紫外光度法具有良好的准确度和精确度,适用于长时间测定硫化氢混合气体浓度。 相似文献
320.
介绍我国粘胶纤维生产废气治理研究的发展情况,说明普通活性炭不适合作为粘胶纤维生产废气的吸附剂、建议采用密封窗封闭操作、用TF法脱除H2S,再用改性活性炭脱除CS2,同时应重视研究开发新型溶剂代替CS2进行无害化清洁生产.关键词:粘胶纤维废气治理硫化氢二硫化炭 相似文献