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61.
介绍PDP11—24计算机在兰州炼油化工总厂第一套催化裂化装置的应用情况,其内容包括数据采集、软件开发、数据通讯等。  相似文献   
62.
Due to the importance of phase diagrams in a wide range of material based industries, additional efforts should be dedicated to their elaboration techniques. The cluster variation method is a promising technique to model the entropy within different plane lattices and is recognized by the materials physics community as a powerful modeling framework. Motivated by the efficiency of genetic algorithms in solving numerous types of optimization problems, our aim in this work is to investigate their performance in minimizing the grand potential in the context of the cluster variation method. A comparison is conducted with respect to numerical iterative techniques namely the Newton-Raphson and natural iteration methods, where many performance criteria are computed and compared. The obtained results allow the ranking of the considered approaches according to their performance measures and suggest a more profound investigation of metaheuristics particularly for complicated cluster structures in the future.  相似文献   
63.
采用X射线粉末衍射和扫描电子显微镜研究了保温时间对废催化裂化平衡剂合成莫来石的影响。结果表明,二次莫来石化反应发生在1 450 ℃,保温3 h后,莫来石质量分数达94%,晶体发育良好;当保温时间超过4 h,由于反应物中Si4+被Al3+取代,导致空位增多,过渡金属进入结构的空位,使莫来石熔点降低,表现为保温时间越长,液相越多,莫来石晶体粘结于液相之中,使机械性能降低。由此可见,保温时间对二次莫来石生成反应影响较大。  相似文献   
64.
The design of catalytic distillation (CD) columns is a challenging task because of the superposition of chemical reaction and distillation in one apparatus. In this work, a method to design a cost-optimal CD column for chemical systems with large number of components and chemical reactions is presented. The method is based on the following steps: (1) estimation of the number of theoretical stages and catalyst volume by the decomposition of the CD column into a sequence of chemical reactors and non-reactive distillation columns, (2) estimation of the column diameter and operating conditions using an equilibrium stage model, and (3) design of the column applying an optimisation algorithm and using a rigorous non-equilibrium stage model to represent the CD process. The method is applied to determine the optimal column configuration and operating conditions for the synthesis of tert-amyl ethyl ether from ethanol and isoamylenes. Eight components and four chemical reactions were selected to represent the chemical system in the simulations.  相似文献   
65.
在中国石油格尔木炼油厂25万t/a催化裂化汽油加氢补充脱硫装置上进行了GARDES系列加氢催化剂的工业应用。结果表明,在原料经过上游装置一次加氢后,硫含量为800μg/g、硫醇硫含量为35μg/g的情况下,其加氢补充脱硫产品硫含量可降低到60μg/g以下,硫醇硫含量降低到10μg/g以下,辛烷值损失小于4.5个单位,产品可达到汽油国Ⅳ指标要求。长周期运行结果显示,各反应器入口温度基本维持不变,床层温升稳定,表明GARDES系列催化剂具有很好的加氢脱硫活性与稳定性。  相似文献   
66.
对国内某催化裂化装置再生斜管的支撑方案进行了分析,详细阐述了支撑方案中支撑碟簧的选型设计,包括计算壳体壁温和两器系统各部分热膨胀值,并对设置碟簧前后的斜管两固定端受力进行了对比:膨胀节前后设置碟簧支撑比未设置时受力减少78%以上.同时也对再生斜管的衬里结构进行了分析,衬里的设置既要考虑到隔热,又要考虑到耐磨,并提出了确保衬里施工质量的措施.再生斜管优化设计后,该装置开车2 a,再生斜管运行良好,未出现振动及局部过热现象.  相似文献   
67.
基于生物质焦油氧含量高、品质差的缺陷,本文提出将生物质与重油共转化利用的方法。以催化裂化油浆(FCC)、稻壳(RH)、木屑(PS)为原料,通过低温固定床热解实验对其共热解产物分布进行了研究。结果表明,在FCC的供氢作用下,共热解有利于焦油中含氧化合物的脱除,随着生物质比例增加,反应过程中脱羧基、脱羰基反应减弱,脱羟基反应增强,产物中CO、CO2产率较计算值增加幅度减小,水的产率较计算值逐渐增大。焦油中烃类物质增加,其中芳香烃以二元环和四元环增加为主,脂肪烃中以C13~C20增加为主。整体上,共热解过程促进了半焦产率的增加,焦油产率虽无明显改变但品质得到了显著提升。  相似文献   
68.
Mesoporous amorphous silica-aluminas were synthesised with standard aluminium and silicon sources by means of the formation of inorganic–organic composites with the addition of chitosan biopolymer, and compared to analogous catalysts synthesised conventionally. Some catalysts were subjected to hydrothermal treatment. The resulting specific surface areas were from 480 to 573 m2/g in the untreated samples and 300–430 m2/g in the hydrotreated catalysts, average pore sizes ranging from 32 to 100 Å with sharp, unimodal distributions. The chitosan materials showed higher specific surface areas and larger pore sizes than those of their non-chitosan counterparts. The most important differences in the acidic properties were in the relationships between tetrahedral and octahedral aluminium atoms, the chitosan materials having higher relative amounts of tetrahedral aluminium than the conventional silica-aluminas. Evidences of stabilization in the physical and chemical properties were observed in the chitosan-containing catalysts. The catalytic performance was evaluated with the conversion of tri-isopropylbenzene at 400 °C, to assess activity and accessibility, and cyclohexene at 300 °C, to assess hydrogen transfer properties. The highest activity and accessibility was observed in the hydrotreated, chitosan-containing catalyst, while hydrogen transfer capabilities were similar to those of medium unit cell sizes, equilibrium commercial FCC catalysts.  相似文献   
69.
提出用变压吸附法提纯催化裂化再生烟气或炼钢高炉尾气中的CO,通过甲醇液相氧化羰基化法生产DMC的工艺路线。这对提高企业经济效益,减轻环境污染,促进资源的合理利用,有重大而深远的意义。  相似文献   
70.
The synergetic effects of HY-zeolite and silica-alumina (SA), as two major components of an FCC catalyst, on the cracking activity and coking tendency during catalytic cracking of 1,3,5-triisopropylbenzene (TiPB, as a resid representative) were studied. NaY-zeolite and SA were synthesized by hydrothermal and co-precipitation methods, respectively, and ammonium exchanged for three times at 80 °C. The catalysts were characterized by XRD, XRF, SEM, BET, AAS and ammonia TPD techniques. TiPB cracking was investigated on four different catalyst configurations including SA, Y-zeolite, SA.Y and SA-Y in a fixed bed reactor. SA.Y stands for physical mixture of equal amounts of Y-zeolite and SA. For SA-Y, a bed of SA was placed upstream of the same amount of Y-zeolite. The catalysts were in-situ activated at 475 °C and evaluated by TiPB cracking at 350 °C. The coke content of the catalyst beds, after 40 min cracking of TiPB, was estimated by TPO using an FT-IR gas cell. At 3 min time on stream, 5.2 times higher yield of benzene, as a deep cracking product, is observed on SA-Y as compared to SA.Y. The TiPB conversion decreases in the order of SA-Y > SA.Y > Y-zeolite ? SA. Furthermore, as compared to Y-zeolite, 24% lower coke is formed on SA-Y. Also CO evolution during TPO of coked SA-Y catalyst is about 24% lower than that of the coked zeolite. As a result, protecting of Y-zeolite by SA from direct exposure to resid feed enhances the cracking activity, decreases the tendency to coke formation and diminishes CO emission in the catalyst regeneration process.  相似文献   
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