Robust optimal operation of continuous catalytic reforming process under feedstock uncertainty

The continuous catalytic regenerative (CCR) reforming process is one of the most significant sources of hydrogen production in the petroleum refining process. However, the fluctuations in feedstock composition and flow rate could significantly affect both product distribution and energy consumption. In this study, a robust deviation criterion based multi-objective optimization approach is proposed to perform the optimal operation of CCR reformer under feedstock uncertainty, with simultaneous maximization of product yields and minimization of energy consumption. Minimax approach is adopted to handle these uncertain objectives, and the Latin hypercube sampling method is then used to calculate these robust deviation criteria. Multi-objective surrogate-based optimization methods are next introduced to effectively solve the robust operational problem with high computational cost. The level diagram method is finally utilized to assist in multi-criteria decision-making. Two robust operational optimization problems with different objectives are solved to demonstrate the effectiveness of the proposed method for robust optimal operation of the CCR reforming process under feedstock uncertainty.     

NNI-1型C_5/C_6烷烃异构化催化剂长周期运行分析及建议

中国石化海南炼油化工有限公司0.2 Mt/a C5/C6烷烃异构化装置以连续重整装置的拔头油为原料,使用NNI-1催化剂,采用一次通过流程,不设脱异戊烷塔和稳定塔,经设在连续重整装置内的脱丁烷塔稳定处理后作为汽油调合组分。该装置于2006年9月开工投产,截至2015年3月已连续运行3个周期。长周期运行分析结果表明:前两个周期中NNI-1催化剂具有较高的异构化活性及选择性,C5异构化率为60%左右,C6异构化率为80%左右,C6选择性为15%左右,产品辛烷值基本达到技术指标要求(RON≥78);而在第三周期运行中,催化剂积炭增加等原因导致其异构化活性及选择性降低,异构化产品辛烷值提升能力呈现逐步衰减的趋势,提高反应苛刻度已不能弥补催化剂活性下降造成的产品辛烷值降低。为保证装置长周期运行,建议择机停工对催化剂进行再生,或是直接换用与装置原料性质匹配的异构化催化剂。     

渣油催化临氢热转化钼铁双金属催化剂的研究

Replacement of precious single metal catalysts with cost-effective, highly-dispersed composite catalysts for catalytic hydrothermal conversion of residue holds tremendous promise for the residue upgrading technologies. Organic metals were added to the feed as the oil-soluble precursors, and transformed into the catalytic active phases in this work. Physical properties and structures of the composite catalysts had been investigated by X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and transmission electron microscopy. The composite catalysts were found to be highly efficient in the catalytic hydrothermal conversion of both model compound and residue. Increased metal dispersion and synergistic effects of two metals played indispensable roles in such catalytic system. Results showed that under the test conditions in the article, the catalyst had the best catalytic performance when the mass ratio of molybdenum to iron was 1.5.     

β-环糊精修饰Ni/SFCC强化C9石油树脂催化加氢性能

以废弃的流化催化裂化催化剂（简称SFCC）为载体、β-环糊精为金属络合剂、硝酸镍为镍源，采用湿法浸渍法制备β-环糊精修饰的Ni/SFCC催化剂（简称Ni/SFCC-CD催化剂），考察其对C9石油树脂的催化加氢性能。通过BET比表面积测试、H2程序升温还原、X射线光电子能谱等手段对催化剂的物相结构进行表征，研究β-环糊精的作用机理及其对催化剂加氢性能的影响。研究结果表明：在反应温度为260 ℃、反应压力为7 MPa、反应时间为2.0 h的最优条件下，采用Ni/SFCC-CD催化C9石油树脂加氢，可制得溴值为1.45 gBr/（100 g）、色号（加纳德）小于1的水白色氢化C9石油树脂，催化剂循环使用4次后仍保持良好活性；β-环糊精的作用机理是：β-环糊精与硝酸镍产生络合作用，抑制硝酸镍的分解、控制NiO的结晶过程和增强活性组分Ni与载体之间的相互作用力，从而提高了Ni/SFCC-CD的催化活性和稳定性。     

Investigation of flame spray synthesized La1-xSrxCoO3 perovskites with promotional catalytic performances on CO oxidation

To enhance the activity of catalysts for CO removal, the perovskite-type catalysts La_1-xSr_xCoO₃ (x = 0, 0.2, 0.4, 0.6, and 0.8) with different Sr²⁺ doping amount were synthesized by flame spray synthesis (FSS) method. The perovskite-type catalyst synthesized by FSS has a much larger specific surface area (SSA) than that prepared by other conventional methods. The SSA of catalyst increases with the increase of Sr²⁺ doping amount and the SSA of La_0.2Sr_0.8CoO₃ reaches 31.65 m²/g. Compared with other conventional methods, FSS method significantly improves the activity of catalyst and makes it close to the performances of catalysts with surface modification. The substitution of La³⁺ by Sr²⁺ promotes the generation of secondary phase Co₃O₄ and SrCO₃. The catalytic activity of La_1-xSr_xCoO₃ increases with the addition of Sr²⁺, which results from the increasing active sites and oxygen vacancies. Interestingly, La_0.4Sr_0.6CoO₃ performs the highest activity for CO oxidation and the CO conversion reaches 50% at 148.6 °C and 90% at 165.9 °C. The oxidation of CO over La_1-xSr_xCoO₃ catalyst may follow a combination of MvK and L-H mechanisms according to the experimental results of H₂-TPR. Moreover, the catalyst exhibits good catalytic activity in consecutive oxidation cycles. In consecutive oxidation experiments with La_0.4Sr_0.6CoO₃, the CO conversion reaches 50% at 168.8 °C and 90% at 197.8 °C in the eighth oxidation cycle. These results prove that FSS method can further improve the activity of catalysts and is suitable for the preparation of efficient catalysts.     

Kinetic,thermodynamic parameters and in vitro digestion of tannase from Aspergillus tamarii URM 7115

Tannase is an enzyme used in various industries and produced by a large number of microorganisms. The aim of this study was to evaluate tannase production to determine the biochemical, kinetic, and thermodynamic properties and to simulate tannase in vitro digestion. The tannase-producing fungal strain was isolated from “jamun” leaves and identified as Aspergillus tamarii. Temperature at 26°C for 67?h was the best combination for maximum tannase activity (6.35-fold; initial activity in Plackett–Burman design—15.53?U/mL and average final activity in Doehlert design—98.68?U/mL). The crude extract of tannase was optimally active at 40°C, pH 5.5 and 6.5. Moreover, tannase was stimulated by Na⁺, Ca²⁺, Mg²⁺, and Mn²⁺. The half-life at 40°C lasted 247.55?min. The free energy of Gibbs, enthalpy, and entropy, at 40°C, was 81.47, 16.85, and ?0.21?kJ/mol?·?K, respectively. After total digestion, 123.95% of the original activity was retained. Results suggested that tannase from A. tamarii URM 7115 is an enzyme of interest for industrial applications, such as gallic acid production, additive for feed industry, and for beverage manufacturing, due to its catalytic and thermodynamic properties.     

提高催化裂化装置(FCCU)柴汽比措施

为了满足市场的需要,中石化天津分公司炼油厂根据FCCU自身特点采取了一系列提高柴汽比的措施,包括:调节反应系统和分馏的操作条件及采用MGD技术,以提高柴油产率。实施后,FCCU的柴汽比从0.5提高到0.9,创造了良好的经济效益。     

先进控制技术在重油催化裂化装置的应用

介绍了由浙江中控软件技术有限公司和镇海炼油化工股份公司(镇海炼化)共同开发的重油催化裂化装置先进控制系统,以及该系统在镇海炼化的工业应用情况.详细阐述了该控制系统的控制策略.工业实践表明,模型和控制策略的综合应用明显地改善了先进控制系统的适应性.先进控制系统的应用明显提高了装置的操作平稳率和产品质量的稳定性,提高了装置的掺渣率,经济效益显著.     

SO4^2-／ZrO2固体超强酸的制备及其催化合成ETBE的研究

采用沉淀一浸渍法制备了负载型SO4^2-／ZrO2固体超强酸催化剂，运用IR、XRD等方法表征所制备催化剂的物化性质。结果表明，所制备的催化剂具有固体超强酸催化剂的特征，酸性与焙烧温度有关，适当提高焙烧温度有利于样品酸强度的提高，但焙烧温度过高会导致脱硫；浸渍液H2SO4浓度高有利于提高催化剂的硫含量，但是浓度过高，会在催化剂上形成硫酸盐，从而降低催化剂的比表面积和酸性。采用制备的催化剂气相催化乙醇与叔丁醇合成乙基叔丁基醚反应，乙基叔丁基醚的选择性为54．71％。     

基于中压加氢改质方案的炼油流程协同优化

中国石化北京燕山分公司(简称燕山分公司）为增产高附加值产品、提升效益，对炼油系统进行了流程协同优化。中压加氢裂化装置掺炼催化裂化柴油，由加氢裂化方案改为加氢改质方案运行，将改质柴油送入三号催化裂化装置（简称三催化装置）的提升管进行回炼；同时，将焦化蜡油改入加氢裂化装置进行加工，而蜡油加氢装置不再加工焦化蜡油以改善催化裂化原料。协同优化后，中压加氢改质装置的柴油产品十六烷值提高7个单位；三催化装置的液化气收率提高1.96百分点，汽油收率增加0.88百分点，总液体收率增加2.28百分点；高压加氢裂化装置喷气燃料产品的密度（20 ℃）降低至806 kg/m3，烟点为23.8 mm，尾油BMCI由11.8降低至10.8；蜡油加氢装置精制蜡油的饱和分质量分数提高4.68百分点，芳香分质量分数降低5.96百分点，氮质量分数降低0.06百分点，使催化裂化原料性质得以改善。通过将中压加氢改质装置的喷气燃料馏分抽出送催化裂化装置回炼，与回炼改质柴油相比，催化裂化汽油的研究法辛烷值（RON）增加1.0个单位，改质柴油十六烷值提高4.8个单位。通过全炼油板块系统性优化，燕山分公司车用柴油产品的十六烷值由53.5降低至51.5，解决了质量过剩问题。