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11.
天然气管网设施公平开放和依法监管是绝大多数市场化比较成熟国家的一致选择。中国的天然气管网改革才刚刚起步,特别是在省级管网设施的监管方面,面临诸多现实问题。为此,以陕西省为例,剖析了我国当前省级天然气管网公平开放面临的主要问题:(1)省管网公司采取统购统销模式,不适应公平开放制度管输业务独立的客观要求;(2)省内管输价格管理办法和成本监审办法待建立,管输价格合理性亟待监审;(3)储气调峰和两部制管输定价缺位,不适应公平开放定价规则;(4)居民和非居民用气实行"双轨"制,不利于市场健康快速发展;(5)储气调峰设施建设滞后,影响供气稳定性和开放准入;(6)管网开放更具操作性的规章制度准则有待于完善。由此建议近期的监管工作重点应从以下5个方面入手:(1)督促省内管输企业扎实履行信息公开义务;(2)监管管网设施信息和运营信息公开的及时全面真实有效;(3)推动省内管输价格管理办法和成本监审办法尽早出台;(4)推动省内管网公司管输与销售、管输与下游业务分离;(5)推动大用户直供,改变省网公司统购统销模式。  相似文献   
12.
Series of modified with vanadium, cobalt, nickel, manganese and copper montmorillonite were compared as additives for desulfurization during combustion of hard coal. Samples of coal with added montmorillonite were subject to a 2 h a flow reactor in the air atmosphere, at 1173 K. The weight ratio of montmorillonite:coal was 1:500. Changes in sulfur dioxide contents in flue gasses caused by the additive were investigated by means of an exhaust gas analyzer. During the co-combustion of coal with montmorillonite modified with vanadium was removed 58-84% of SO2 from flue gasses. Application of Co and Ni led to a reduction in SO2 emissions by 35-53% and 83-90%, respectively. For additions of Ni, Cu and Mn was observed to reduce emissions of SO2 by 60-73%. As a result of using diversified preparatory procedures on montmorillonite additives DESOX obtained were materials with different physicochemical properties. Sulfate forms obtained after the combustion process with addition of montmorillonite additives are amorphous and very well dispersed.  相似文献   
13.
Yuuki Mochizuki 《Fuel》2011,90(10):2974-2980
The objective of this study was to develop an efficient cleaning process for hydrocarbon resources. We investigated the removal of organic sulfur from coal extract by using metal-loaded carbons. Tetralin and tetralin/phenol mixture were used for thermal extraction of Illinois No. 6 coal at 375 °C with a holding time of 1 h, and we examined the effects of temperature on product yield and sulfur-removal behavior using metal-loaded carbons. A decrease in the n-hexane insoluble fraction was observed at a temperature range from 200 °C to 250 °C in the extracts of tetralin and tetralin/phenol mixture. The organic sulfur content in the n-hexane insoluble fraction drastically decreased with increasing temperature. The organic sulfur in the n-hexane insoluble fraction was reduced above 200 °C, while the sulfur content reached 30-35% at 375 °C for both tetralin and tetralin/phenol mixture extracts. We investigated the effect of holding time on the extent of the coal extract desulfurization using Ni-loaded carbon. The sulfur content in the coal extract decreased as the holding time increased. The rate of coal extract desulfurization using tetralin/phenol was slower than that obtained using tetralin. The coal extract obtained using the tetralin/phenol mixture contained a heavier polar fraction, which may have impeded the adsorption. All organic sulfur in the coal extract could be successfully removed Ni-loaded carbon at a treatment temperature of 350 °C and a holding time of 8 h. No appreciable changes were observed in the content of carbon, hydrogen, or nitrogen at any temperature or holding time in the ultimate analysis of the n-hexane insoluble fraction treated with Ni-loaded carbon. The results demonstrated that Ni-loaded carbon was much effective in removing organic sulfurs from the coal extract.  相似文献   
14.
王昌东  郝凤林  王强 《当代化工》2011,40(7):666-668
用空气处理的ZSM-5型分子筛作为载体,以硝酸铜为活性组分,制备一种FCC汽油吸附脱硫催化剂。改变反应器温度、空气处理温度以及空气流速制备一系列载体,在载体上负载不同质量分数的硝酸铜溶液,得到催化剂。利用制备的催化剂在微型反应装置中进行FCC汽油脱硫实验,考察温度、空速对催化剂吸附脱硫活性的影响。结果表明:对ZSM-5型分子筛的处理温度为600℃处理时间为7 h,活性组分的质量分数为10.0%,吸脱附床层温度为30℃,常压,空速为0.3 h-1时,催化剂具有较好的催化活性,吸附脱硫率78.1%。  相似文献   
15.
以2,2′-二苯甲酰氨基二苯基二硫化物(DBADPDS)作为再生剂在密炼机中对废乳胶(WLR)进行脱硫再生,研究环烷油、再生剂用量和脱硫温度对脱硫效果的影响,并探讨脱硫机理。结果表明:随着环烷油用量的增大,再生胶的交联密度减小,脱硫效果增强;添加再生剂DBADPDS可以增强脱硫效果,但再生剂DBADPDS用量过大时,其含有的硫在高温下能参与WLR分子链间的交联反应,导致再生胶的交联密度增大;脱硫温度高于140℃,橡胶很容易发生裂解,脱硫过程中温度控制在120℃左右比较适宜。  相似文献   
16.
随着2020年国际海事组织(International Maritime Organization,IMO)船用燃料油限硫政策的施行,船用残渣型燃料油的脱硫技术受到了业界的较大关注.重质原料油是船用残渣型燃料油的主要组成部分,重质原料油脱硫技术分为加氢技术和非加氢技术.加氢技术主要有固定床、沸腾床(膨胀床)、悬浮床(浆...  相似文献   
17.
燃煤火力电厂脱硫废水零排放可行性研究   总被引:1,自引:0,他引:1  
燃煤电厂脱硫废水因高含盐量、成分复杂、高腐蚀性、回用困难的特点成为制约燃煤电厂废水零排放的关键因素。三种脱硫废水零排放可行性技术方案,通过对比工艺流程、经济指标和占地因素等指标,发现熟石灰、碳酸钠两级软化+卧式MVC蒸发浓缩+卧式MVC蒸发结晶是最优方案,可获得高品质工业盐再利用,作为未来基建项目脱硫废水零排放系统工艺方案。  相似文献   
18.
纳米级石灰石钙基脱硫试验研究   总被引:1,自引:0,他引:1  
考虑到纳米微粒的粒径小,比表面大的特点,在一维热态试验台上,研究了纳米级钙基吸着剂脱硫过程.结果表明,纳米级石灰石普遍具有很好的脱硫效果,不同纳米石灰石,由于其比表面积、粒径以及内部成份、结构等的不同,脱硫率明显不同;粒径,温度和SO2浓度是影响脱硫的关键因素,在最佳温度1000℃、粒径为100nm,Ca/S=1.5和SO2浓度为2000ppm的条件下,其脱硫率可达90%以上.  相似文献   
19.
A continuous-flow ultrasound-assisted oxidative desulfurization(UAOD) of partially hydro-treated diesel has been investigated using hydrogen peroxide-formic acid as simple and easy to apply oxidation system. The effects of different operating parameters of oxidation stage including residence time(2–24 min), formic acid to sulfur molar ratio(10–150), and oxidant to sulfur molar ratio(5–35) on the sulfur removal have been studied using response surface methodology(RSM) based on Box–Behnken design. Considering the operating costs of the continuous-flow oxidation stage including chemical and electrical energy consumption, the appropriate values of operating parameters were selected as follows: residence time of 16 min, the formic acid to sulfur molar ratio of 54.47, and the oxidant to sulfur molar ratio of 8.24. In these conditions, the sulfur removal and the volume ratio of the hydrocarbon phase to the aqueous phase were 86.90% and 4.34, respectively. By drastic reduction in the chemical consumption in the oxidation stage, the volume ratio of the hydrocarbon phase to the aqueous phase was increased up to 10. Therefore, the formic acid to sulfur molar ratio and the oxidant to sulfur molar ratio were obtained 23.64 and 3.58, respectively, which lead to sulfur removal of 84.38% with considerable improvements on the operating cost of oxidation stage in comparison with the previous works.  相似文献   
20.
阐述了国内近几年FCC催化剂在重油催化裂化、汽油降烯烃、脱硫及多产低碳烯烃方面的进展.提高抗重金属污染能力、用中孔沸石代替 ZSM-5小孔沸石及大幅度提高催化剂基质的活性仍是今后研发 FCC催化剂的热点.  相似文献   
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