延迟焦化-加氢裂化-催化裂化联合工艺的应用

利用加氢裂化装置扩能改造时新增的一个反应器,对经过过滤的劣质焦化蜡油和高硫直馏蜡油进行高压加氢精制,为催化裂化装置提供原料,催化裂化油浆则掺入焦化原料中,形成延迟焦化-加氢裂化-催化裂化联合工艺技术。在扩大催化裂化装置原料来源的同时优化了该装置的原料结构,从而改善了产品分布和产品质量,提高了炼油厂含硫油加工能力及深度加工能力。

加氢裂化装置掺炼焦化催化柴油的技术应用

为了实现节能降耗、优化加工流程的目标,大庆石化公司炼油厂对加氢裂化装置原料进行了调整,掺炼焦化柴油和部分催化轻、重柴油。加氢裂化装置原料变更后,经过操作条件的调整,生产运行平稳,产品分布合理,优化了炼油厂二次加工原料配置,达到节能降耗的目的。

含油泥砂工业化处理工艺

大港油田公司每年产生危险油泥砂(包括落地原油和油泥砂)高达8 398 t,对环境和企业生产造成很大的影响,目前多个联合站的油泥、油砂已经无法堆放,影响到生产工艺的正常运行。通过工艺调研,确定了物理化学洗涤工艺是最适合工业化处理大港南部油田含油泥砂的工艺技术。根据含油泥砂老化严重,破乳困难,重油、胶质和沥青质含量多的特性,实验确定了最佳的物理化学药剂和污水处理药剂。通过经济运行费用的比较,证实了采用物理化学洗涤工艺作为工业化处理大港油田含油泥砂具有一定的经济和社会效益。

Development and Commercial Application of High-Platinum CCR Catalyst with Low Coke Deposition Rate

By means of selecting proper additives and optimizing catalyst composition and preparation procedures, a high-platinum and low coke deposition catalyst PS-Ⅶ for continuous catalytic reforming （CCR） without reducing its specific surface area has been successfully developed. This catalyst PS-Ⅶ was evaluated in a 100-mL pilot test unit. Study results showed that under the same reaction conditions the newly developed catalyst PS-Ⅶ achieved a 26% reduction in coke deposition as compared to the existing high-platinum CCR catalyst. This catalyst upon its first commercial application in a 1.39 Mt/a CCR unit had exhibited good anti-attrition performance and good stability in terms of its specific surface area. Compared to the original CCR catalyst this PS-Ⅶ type catalyst could reduce the coke deposition by 27.32% when operating on feedstock with low potential aromatic content, along with apparent increase in C6^＋ liquid yield, hydrogen yield and aromatics yield, which could grapple with the problem associated with the catalyst regeneration constraints after CCR capacity expansion to ensure the longcycle high-load operation of the CCR unit.

Characterization of Catalytic Cracking Catalysts Regenerated by Gasifying Deposited Coke

Partially or fully regenerated catalytic cracking catalysts were prepared by gasifying the coke deposited on coked catalysts with a gaseous mixture of oxygen and steam in a fixed fluidized bed （FFB）. The resultant samples were characterized by different methods such as the nitrogen adsorption-desorption analysis, the X-ray diffractometry, the infrared spectroscopy, the ammonia temperature-programmed desorption （NH3-TPD） method, the X-ray fluorescence （XRF） analysis, the transmission electron microscopy and energy dispersive X-ray spectroscopy （TEM-EDX）, the thermal-gravimetric analysis （TGA） and the differential thermal analysis （DTA）. The results showed that exposure of catalyst to steam for about 10 minutes at temperature ≥ 800 ℃ could not cause too much destruction of the catalysts, and an amount of coke equating to about 0.27 m% was enough to block approximately all acid sites in micro-pores of the zeolite catalyst. Coke didn＇t show equal reactivity during coke burning-off that could be accelerated by the catalytic action of nearby metal atoms. However, when the carbon content on the catalyst reached about 2.44 m%, the catalytic action of metals on the catalyst was not evident. The severe thermal and hydrothermal environment during exposure of the catalyst to steam at a temperature in the range of about 860--880 ℃ for 30 minutes could lead to collapse of pore structure and transformation of crystal phase and consequently decrease of the surface area and acid amount on the catalyst.

Catalytic cracking mechanisms of tar model compounds

B3LYP/6-31G(d,p) method was used to investigate the catalytic cracking mechanism of biomass tar model compound.Phenol,toluene and benzene were selected as the tar model compounds and CaO was selected as the catalyst.The pathways of tar compound radical absorbed by CaO were determined firstly through comparing enthalpy changes of the absorption,and then Mulliken population changes were analyzed.The results show that the absorption of tar model compound radical and CaO is an exothermic reaction.Formation of C—O—Ca is more easily than that of C—Ca—O and formation of Caromatic—Caromatic—Ca—O is more easily than that of Caromatic—C(O)—Ca—O.The C—C bond Mulliken populations in tar model compound radicals are reduced by 11.9%,10.5% and 15.5% in the case of a hydrogen atom removed,and those are 15.7%,14.3% and 16.3% in the case of two hydrogen atoms removed through the absorption of CaO.Catalytic ability of CaO acting on the tar model compound is in an order of phenol>benzene>toluene.

The correlation between nitrogen species in coke and NO_x formation during regeneration

Nitrogen oxides （NOx） emission during the regeneration ofcoked fluid catalytic cracking （FCC） catalysts is an en- vironmental issue. In order to identify the correlations between nitrogen species in coke and different nitrogen- containing products in tail gas, three coked catalysts with multilayer structural coke molecules were prepared in a fixed bed with model compounds （o-xylene and quinoline） at first. A series of characterization methods were used to analyze coke, including elemental analysis, FT-IR, XPS, and TG-MS. XPS characterization indicates all coked catalysts present two types of nitrogen species and the type with a higher binding energy is related with the inner part nitrogen atoms interacting with acid sites. Due to the stronger adsorption ability on acid sites for basic nitrogen compounds, the multilayer structural coke has unbalanced distribution of carbon and ni- trogen atoms between the inner part and the outer edge, which strongly affects gas product formation. At the early stage of regeneration, oxidation starts from the outer edge and the product NO can be reduced to N2 in high CO concentration. At the later stage, the inner part rich in nitrogen begins to be exposed to 02. At this period, the formation of CO decreases due to lack of carbon atoms, which is not beneficial to the reduction of NO. There- fore, nitrogen species in the inner part of multilayer structural coke contributes more to NOx formation. Based on the multilayer structure model of coke molecule and its oxidation behavior, a possible strategy to control NOx emission was discussed merely from concept.

Investigation on the catalytic effects of AAEM during steam gasification and the resultant char reactivity in oxygen using Shengli lignite at different forms

The purpose of this study is to investigate the catalytic effects of alkali and alkaline earth metallic species （AAEM） on char conversion during the gasification in steam and the changes in ex-situ char reactivity in oxygen after the gasification in steam using different forms （i.e. H-form, Na-form） of Shengli brown coal. The surface area, AAEM concentration and carbon crystallite of chars were obtained to understand the change in char reactivity. It was found that not only Na concentration and carbon structure were the main factors governing the char reactivity in the atmosphere of steam and oxygen, but also they interacted each other. The presence of Na could facilitate the formation of disordering carbon structure in char, and the amorphous carbon structure would in turn affect the distribution of Na and thus its catalytic performance. The surface area and pore volume had very little relationship with the char＇s reactivity. Addi- tionally, the morphology of chars from different forms of coals were observed using scanning electron microscope （SEM）.

Laboratory Research on Tahe AR Fluid Coking on Weak Acid Catalysts

Fluid coking on micro-spherical particles with acid sites on them could produce more light oils from Tahe AR.The conversion rate could increase by about 20% on the catalyst B compared to that obtained on the catalyst A and the light oil yield could increase by about 12%.The yield of gasoline and diesel was more than 50% from Tahe AR over the catalyst B.Tests on acidity of the catalyst B by pyridine FT-IR spectrometry showed that the total acid content and the ratio of weak acid number to total acid number were higher than other catalysts.

Suitability of Sour Crude Processing and Resid Hydrotreating Technologies

This article has analyzed the environment and tasks confronting China's petroleum refining industry, and has referred to principles for selecting the resid processing technologies and viability of various combination technologies for resid processing. Taking into account the actual commercial practice of resid hydrogenation units, this article has also discussed methods for processing high-sulfur inferior crudes as well as the suitability of resid hydrogenation technology.

Synthesis of Polyalphaolefins on AlCl_3/TiCl_4 Catalyst

The oligomerzation reactions on different catalysts were investigated and discussed. 1-Octene, 1-decene, 1-do- decene, a mixture of olefins （with a mass ratio of w（l-octene）： w（1-decenc）：w（1-dodecene） equating to 30：40：30）, and the products from paraffin cracking were oligomerized on the AlCl3/TiC14 catalyst. The results indicated that the AlCl3 catalyst led to severe coking reaction. With an increase in carbon number of alpha-olefins, the freezing point of oligomers increased and the kinematic viscosity decreased. The oligomers formed from the mixed olefins and the paraffin cracking products showed higher kinematic viscosity. Normal paraffins contained in the cracked products could increase the freezing point of oligomers. Furthermore, the distillation range of oligomers obtained from the cracked products was close to those of oligo- mers originated from 1-octene and 1-decene, while the oligomers obtained from the mixed olefins and 1-dodecene had simi- lar distillation ranges.

Conversion and reaction kinetics of coke oven gas over a commercial Fe-Mo/Al_2O_3 catalyst

Producing methanol from coke oven gas(COG) is one of the important applications of COG. Removal of sulfur from COG is a key step of this process. Conversion and reaction kinetics over a commercial Fe-Mo/Al2O3 catalyst(T-202) were studied in a continuous flow fixed bed reactor under pressures of 1.6-2.8 MPa, space time of 1.32-3.55 s and temperatures of 240-360 °C. Though the COG contains about 0.6 mol/mol H2, hydrogenation of CO and CO2 is not significant on this catalyst. The conversions of unsaturated hydrocarbons depend on their molecular structures. Diolefins and alkynes can be completely hydrogenated even at relatively low temperature and pressure. Olefins, in contrast, can only be progressively hydrogenated with increasing temperature and pressure. The hydrodesulfurization(HDS) of CS2 on this catalyst is easy. Complete conversion of CS2 was observed in the whole range of the conditions used in this work. The original COS in the COG can also be easily converted to a low level. However, its complete HDS is difficult due to the relatively high concentration of CO in the COG and due to the limitation of thermodynamics. H2 S can react with unsaturated hydrocarbons to form ethyl mercaptan and thiophene, which are then progressively hydrodesulfurized with increasing temperature and pressure. Based on the experimental observations, reaction kinetic models for the conversion of ethylene and sulfur-containing compounds were proposed; the values of the parameters in the models were obtained by regression of the experimental data.

Influence of ultrasonic on the coking amount of catalyst （Ni/γ-Al2O3） for the dry reforming of benzene

The Influence of ultrasonic treatment on the coking amount of a nickel-based catalyst （Ni/γ-Al2O3） for the reaction of reforming with carbon dioxide of Benzene was investigated. The results show that ultrasonic treatment modify the pore size distribution of the catalysts significantly and also reduce the amount of coke formed on the catalyst. The reduction in the coking amount is not sensitive to the power output of the ultrasonic treatment device in the power range tested （120 W and 500 W）.