加氢催化剂器外预硫化技术进展

本文概述了加氢催化剂预硫化的方法和基本原理,重点介绍了20世纪80年代以来,EURE-CAT公司、CRITERION公司、AKZO公司、TRICAT公司等国际性公司在加氢催化剂器外预硫化技术领域的发展和突破,同时对国内该领域的技术现状作了具体论述。     

"南梅北移"简介——业绩与展望

梅(Prunus mume)是我国的传统名花和嘉果.历史上,梅树曾广泛分布于黄河流域,自唐末以后,我国冬半年气温降低,其适生区域移至秦岭、淮河以南."南梅北移"的尝试从元末就已开始,但多是保护地栽培.陈俊愉等用直播育苗、实生选种的方法选育出的‘北京小'梅和‘北京玉蝶'2个品种在1962-1964年春天在北京露地开花,开创了"南梅北移"的先河.自1986年起,已在熊岳、北京、赤峰、太原、包头、呼和浩特、延安、兰州、西宁、沈阳、长春、公主岭、大庆、乌鲁木齐等地进行过区域试验,参试品种共计22个.总结抗寒梅花迁地驯化的经验,关键是在顺应植物本性,满足其最低生长发育条件的基础上,步步深入,抓紧某些关键时期,给予"斯巴达"锻炼.植物的迁地驯化应以主导生态因子为导向,梅树在三北地区露地越冬闲难,是干旱、低温、大风和温度的骤变等多种逆境共同作用的结果,而绝对低温和生理干早则是其主导的生态因子.     

中国某场地污染土原地异位稳定化工程实施

以中国某场地污染土原地异位稳定化实体工程为例,介绍了污染场地修复与风险管控技术实施过程中污染土开挖、污染土与稳定剂混合、稳定化效果评估、稳定化土阻隔回填等技术环节。原地异位稳定化处理采用自主研发的稳定剂,其主要成分为过聚合硫酸铁、磷酸钙、氢氧化钙和绿泥石粉。污染土的稳定剂掺量为2%～4%,养护龄期3～7d。经稳定化处理后,目标污染物砷、锑、铜、锌、钒、氟化物浸出浓度满足修复设计要求。施工装备采用污染土修复一体化设备,经该设备处理后,污染土颗粒粒径小于20mm,且污染土和稳定剂的混合均匀度大于95%。稳定化土经采样检测确认达标后,转运至回填区进行阻隔回填。阻隔回填区从下至上依次为压实天然黏土、无纺土工布、HDPE土工膜、无纺土工布、压实稳定化土、无纺土工布、HDPE土工膜和压实清洁土。稳定化土的回填工艺为分层回填、分层碾压,回填厚度为3 m,压实度大于90%。工程的顺利实施,可为同类型污染场地的修复和风险管控提供技术参考。     

Comparison of in-situ and ex-situ microbial enhanced oil recovery by strain Pseudomonas aeruginosa WJ-1 in laboratory sand-pack columns

Microbial enhanced oil recovery (MEOR) applies biotechnology to improve residual crude oil production from substratum reservoir. MEOR includes in-situ MEOR and ex-situ MEOR. The former utilizes microbial growth and metabolism in the reservoir, and the latter directly injects desired active products produced by microbes on the surface. Taking biosurfactant-producing strain Pseudomonas aeruginosa WJ-1 for research objects, in-situ enhanced oil recovery and ex-situ enhanced oil recovery by biosurfactant-producing strain WJ-1 were comparatively investigated in sand-pack columns.The results showed that P.aeruginosa WJ-1 really proliferated in sand-pack columns, produced 2.66 g/L of biosurfactant, altered wettability, reduced oil-water interfacial tension (IFT) and emulsified crude oil under simulated in-situ process. Results also showed that higher biosurfactant concentration, lower IFT, smaller average diameters of emulsified crude oil were obtained in in-situ enhanced oil recovery experiment than those in ex-situ enhance oil recovery experiment. Similar wettability alteration was observed in both in-situ and ex-situ enhanced oil recovery experiment. The flooding experiments in sand-pack columns revealed that the recovery of in-situ was 7.46%/7.32% OOIP (original oil in place), and the recovery of the ex-situ was 4.64%/4.49% OOIP. Therefore, in-situ approach showed greater potential in enhancing oil recovery in contrast with ex-situ approach. It is recommended that the stimulation of indigenous microorganisms rather than injection of microbial produced active products should be applied when MEOR technologies were employed.     

加氢催化剂器外预硫化过程反应放热的研究

在实验室条件下,研究了中国石化催化剂抚顺分公司加氢催化剂A、B、C器外预硫化反应过程的放热情况,考察了载体、金属组分、焙烧以及反应气氛对加氢催化剂硫化反应放热的影响。实验结果表明,加氢催化剂在硫化反应过程中的剧烈放热现象与加氢催化剂上尚未分解的硝酸镍有关,而与载体、金属组分及反应气氛无本质的关系。在N_2气氛下,加氢催化剂在硫化反应过程中的剧烈放热现象得到大幅度延缓和减弱,表明在N_2气氛下进行操作有利于对硫化反应温度的控制。     

预硫化催化剂钝化研究

以硫化度和自放热温度为评价指标,确定了固定床气体钝化适宜工艺条件为:温度50℃,O2浓度1%,时间30min。利用XRD、DTA对催化剂进行了表征并总结出了预硫化催化剂机理。结果表明,钝化催化剂没有出现活性相聚集现象。钝化催化剂的放热峰比硫化态催化剂放热峰低得多,也比较平坦,TGA曲线表明,钝化催化剂在高温有SO2的生成。催化剂经过钝化后活性组分发生了变化,有新相生成,同时改善了硫化催化剂低温热稳定性。     

From fundamental understanding to innovative developments of high-performance composites for aerospace application

In framework of the National Key Basic Research Program (973 Program) we focus our attention on R&D of (1) continuous enhancement of composites performance both for new generation and existing materials, (2) cost-effective manufacturing technologies, particularly resin transfer molding (RTM) in conjunction with textile technology, and (3) crashworthy composite structures in design, and manufacturing and simulation methodology for aircrafts composites. Many successful examples stories such as ex-situ concept have been demonstrated that the performance potential of composites could be enhanced and maximized by basically understandirg the complicated multi-scale and multi-dimensional structural characteristics in relation to properties. Based on the concept, graphite composites system with generally high impact damage resistance and balanced processing conditions has being developed consisting of base resins, modifiers and binders/tackifiers.     

加氢催化剂有机硫化剂器外预硫化技术

以有机硫化物为硫化剂的器外预硫化技术是加氢催化剂预硫化技术的重要发展方向。介绍了有机多硫化物作为硫化剂的预硫化机理；探讨了有机多硫化物在器外预硫化过程中影响催化剂活性的因素，认为浸渍液中硫化剂含量、干燥温度、硫化温度及氢压是影响催化剂活性的主要因素。并对加氢催化剂器外预硫化技术的研究方向提出建议。     

组合加氢催化剂预处理焦化干气

介绍了JT-4／JT-1G加氢催化剂在焦化于气制氢装置中的组合使用情况。结果表明：JT-4／JT-1G加氢催化剂组合具有良好的低温烯烃和有机硫加氢活性，焦化于气经加氢精制后，烯烃的体积分数由4％～7％降为小于0．5％，总硫(有机硫)质量比由300μg/g降到小于0．5μg/g，满足了制氢工艺条件要求，同时降低了催化剂成本。