KINETICS OF HYDRODESULFURIZATION OF HEAVY GAS OIL DERIVED FROM OIL-SANDS BITUMEN

With gradual shortage in the supply of crude oil, the importance of producing synthetic crude oil from oil sands and shale oil is increasing day by day. In the present paper, the effects of various process variables such as temperature, liquid hourly space velocity and hydrogen/heavy gas oil volumetric ratio on the removal of sulfur compounds from oil sands derived heavy gas oil has been studied. The experiments have been carried out in a micro scale trickle bed reactor over a commercial Ni-Mo catalyst. The temperature, liquid hourly space velocity and hydrogen/heavy gas oil volumetric ratio have been varied from 365 to 415°C, 0.5 to 1.9 h^-1 and 400 to 1000 ml, respectively. Under optimum reaction conditions over 96% conversion of sulfur compounds was achieved. The kinetics of the rate of sulfur removal from the oil sands derived heavy gas oil has also been discussed in this article.     

CATALYTIC HYDROTREATMENT OF PETROLEUM RESIDUE

ABSTRACT

Iraqi reduced crude (350°C+) with a sulfur content of 4.3 wt% and a total metal content (Ni+V) of 141 WPPM was n-heptane deasphalted at specified conditions. The deasphalted oil (97.2 wt% of original residue) contains 4.1 wt% of sulfur and 103 ppm of metal. The original reduced crude and deasphalted oil were hydrotreated on a commercial Ni-Mo-alumina catalyst presulfided at specified conditions in a laboratory trickle-bed reactor. The reaction temperatures varied from 300 to 420°C with the liquid hourly space velocity (LHSV) ranging from 0.37 to 2.6 h^?1. Hydrogen pressure was kept constant throughout the experiments at 6.1 MPa, with a hydrogen/oil ratio of about 300 NLL^?1 (normal liters of hydrogen per liter of feedstock). Analysis for sulfur, nickel, vanadium and n-pentane asphaltenes were carried out for hydrotreated products from both the original residue and the deasphalted oil. The comparison of the results obtained for the hydrotreatment of deasphalted oil and original reduced crude indicates that the removal of sulfur, nickel and vanadium was higher for the deasphalted oil than those obtained for the non-deasphalted residue over the entire range of conversion. The exclusion of extremely high molecular weight asphaltenes by n-heptane deasphalting seems to improve the access of oil into catalyst pores resulting in higher desulfurization and conversion of the lower molecular weight asphaltenes. The sulfur content of n-pentane precipitated asphaltenes remained unchaneed with LHSV for various temperature for hydrotreated products produced from both deasphalted oil and original reduced crude.     

CATALYTIC HYDROTREATMENT OF PETROLEUM RESIDUE

Iraqi reduced crude (350°C+) with a sulfur content of 4.3 wt% and a total metal content (Ni+V) of 141 WPPM was n-heptane deasphalted at specified conditions. The deasphalted oil (97.2 wt% of original residue) contains 4.1 wt% of sulfur and 103 ppm of metal. The original reduced crude and deasphalted oil were hydrotreated on a commercial Ni-Mo-alumina catalyst presulfided at specified conditions in a laboratory trickle-bed reactor. The reaction temperatures varied from 300 to 420°C with the liquid hourly space velocity (LHSV) ranging from 0.37 to 2.6 h^-1. Hydrogen pressure was kept constant throughout the experiments at 6.1 MPa, with a hydrogen/oil ratio of about 300 NLL^-1 (normal liters of hydrogen per liter of feedstock). Analysis for sulfur, nickel, vanadium and n-pentane asphaltenes were carried out for hydrotreated products from both the original residue and the deasphalted oil. The comparison of the results obtained for the hydrotreatment of deasphalted oil and original reduced crude indicates that the removal of sulfur, nickel and vanadium was higher for the deasphalted oil than those obtained for the non-deasphalted residue over the entire range of conversion. The exclusion of extremely high molecular weight asphaltenes by n-heptane deasphalting seems to improve the access of oil into catalyst pores resulting in higher desulfurization and conversion of the lower molecular weight asphaltenes. The sulfur content of n-pentane precipitated asphaltenes remained unchaneed with LHSV for various temperature for hydrotreated products produced from both deasphalted oil and original reduced crude.     

MILD HYDROCRACKING OF VACUUM GAS OILS TO IMPROVE FCC PERFORMANCE AND MAXIMIZE DISTILLATE YIELDS

ABSTRACT

A pilot plant study was conducted on mild hydrocracking of heavy vacuum gas oils derived from two different crude sources over a commercially available catalyst to determine the possibility of utilizing mild hydrocracker bottoms as fluidized catalytic cracking feedstock along with improved middle distillate yields. The mild hydrocracking experiments were conducted at 390°C, 60 kg/cm², 1.0/h liquid hourly space velocity and H₂/oil ratio of 390 l/l in a pilot plant trickle bed reactor using two catalyst beds for pretreatment and mild hydrocracking reactions. The experimental results showed that mild hydrocracking would result in valuable middle distillates with low sulphur and nitrogen content. With research octane number of 78, the naphtha obtained from mild hydrocracking was found to be a good blending stock for gasoline pool. The middle distillate fraction (140–370°C) obtained from mild hydrocracking product was found to have cetane number in the range of 48–54. The bottom product from mild hydrocracking of heavy vacuum gas oils was found to be a good feedstock for fluidized catalytic cracking unit because of its low sulphur, nitrogen and aromatic contents. The data obtained from pilot plant studies showed that the processing of mild cracker bottom in FCC unit would result in better quality fuels.     

催化裂化汽油加氢脱硫及芳构化工艺反应条件的研究

在100 mL固定床反应器试验装置上,针对中国石化集团洛阳石油化工工程公司工程研究院开发的催化裂化汽油加氢脱硫及芳构化技术(Hydro-GAP),考察了反应温度,氢分压、进料空速、氢油体积比等工艺条件对加氢脱硫及芳构化反应的影响.结果表明:随着反应温度、氢分压的升高和空速的减小,加氢脱硫性能提高;芳构化性能随反应温度的升高、氢分压的降低而增加.氢油体积比对加氢脱硫及芳构化性能影响不大.     

抚顺页岩油柴油馏分加氢精制的工艺条件

以硫化态Co-Mo/Al2O3为催化剂,利用固定床小型加氢反应装置,考察了反应温度、反应压力、体积空速、氢/油体积比对抚顺页岩油柴油馏分加氢精制效果的影响。结果表明,升高反应温度、增大反应压力、降低体积空速,有利于抚顺页岩油柴油馏分的脱硫、脱氮和烯烃饱和,特别是可明显提高加氢脱氮效果,而氢/油体积比的改变对产物性质影响相对较小。在反应温度380℃、反应压力7MPa、体积空速0.5h-1、氢/油体积比600的条件下,抚顺页岩油柴油馏分加氢精制后,其杂原子和不饱和烃含量低、密度小、芳香烃含量少,可作为优质清洁柴油直接使用。     

Comparison Study for the Distribution of Organo-Sulfur Containing Compounds of Two Kuwaiti Crude Oil Distillates

Abstract

This paper deals with the comparison, analysis, and characterization of two Kuwaiti crude oil samples received from different origins. (Burgan and Al-Wafra oil fields). Systematic analysis was conducted for API gravity, sulfur content, metal content, and viscosity. The representative samples of the two Kuwaiti crude oils were fractionated into naphtha (IBP–170^○C), kerosene (170–265^○C), medium gas oil (265–355^○C), and heavy gas oil (355–550^○C) using an 80 L capacity autodistillation unit “AUTODEST-800” according to ASTM D2892 and ASTM D5236. Particular attention was paid to study the distribution of various types of sulfur compounds in each of these wide cuts, which was qualitatively and quantitatively estimated by capillary gas chromatography equipped with a sulfur chemiluminescence detector, which is suitable for a wide range of sulfur systems. The fingerprinting obtained from the analysis of GC-SCD showed different families of organo-sulfur compounds in crudes, including mercaptans, sulfides, thiophenes, benzothiophenes, dibenzothiophene, benzonaphtothiophene, and their alkyl derivatives. From the analyses the behavior and distribution of the refractory and unrefractory sulfur compounds in the two Kuwaiti crude oils can now be easily followed.     

SULFUR COMPOUND TYPE DISTRIBUTION IN NAPHTHA AND GAS OIL FRACTIONS OF KUWAITI CRUDE

ABSTRACT

The need for detailed information on the types of sulfur compounds present in various petroleum cuts has been well recognized by refiners and environmentalists worldwide. This need is growing in recent years in view of the current environmental regulations that limit the sulfur content of transportation fuels to very low levels. In the present work we have studied the distribution of different kinds of sulfur compounds present in light and middle distillates of Kuwait crude oil. A representative sample of Kuwait crude oil was fractionated into naphtha (15-160°C) and 10-15°C cuts in the gas oil boiling range (210-340°C) using an 80L capacity autodistillation unit “AUTODEST-800” according to ASTM 2892. The distribution of various types of sulfur compounds in each of these cuts was quantitatively estimated by capillary gas chromatography equipped with a sulfur chemiluminescence detector. Thiophene and its alkyl derivatives constituted about 60% of the total sulfur compounds in the naphtha fraction. The remaining 40% was composed of mercaptanes and alkyl sulfides. In the gas oil boiling range (210-340) two groups of sulfur compounds, namely, alkyl benzothiophenes and alkyl dibenzothiophenes were present. A major portion of the alkyl benzothiophenes was found in the fraction boiling in the narrow range 235-257°C. Among the alkyl dibenzothiophenes, the concentration of C, and C₂ DBTs decreased while that of higher alkyl DBTs (< C₃-DBTs) increased with increasing temperature. The C₁ and C₂ alkyl DBTs were highly concentrated in a fraction boiling between 280-325°C and these sulfur compounds were absent in the fraction boiling above 330°C. The industrial implications of these results are discussed.     

Sulfur compounds in the fuel range fractions from different crude oils

A gas chromatograph coupled with sulfur chemiluminscence detector (GC-SCD) has been used for the speciation of individual sulfur compounds in fractions of different crude oils. The crude oil fractions characterized were light naphtha (C5-90°C), heavy naphtha (90–140°C), kerosene (140–240°C), and gas oil (240–370°C) fractions obtained from true boiling point distillation process. Low boiling fractions (up to 140°C) were analyzed by existing ASTM D5623 (American Society for Testing and Materials, 2009a) method for sulfur compound speciation. As there is no standard method for the distribution of sulfur compounds in high boiling samples (up to 370°C), therefore, a methodology has been developed for the diesel range samples. The identification of individual sulfur compounds were carried out by using reference sulfur compounds. The results show that type of sulfur compounds depends upon the boiling range of the fraction and source of crude oil. The major changes in the sulfur compounds profiles of different fractions are discussed. The results of this study can be used to predict the suitability of crude oil for the production of Euro-IV and V gasoline and diesel fuels.     

塔中油田汽提法原油脱硫化氢工艺技术

为了减少塔中联合站处理装置中大量高含H2S原油对非抗硫工艺管线和设备造成的严重腐蚀,消除外输原油和天然气H2S浓度严重超标带来的安全隐患,中国石油塔里木油田公司借鉴国内首套重质原油干法汽提脱硫装置在塔河油田三号联合站试验成功并且安全平稳运行的经验,在塔中作业区水平一转油站建成了日处理能力1 000 t的汽提法原油脱硫装置,对塔中一号气田试采单井原油进行脱硫处理,通过对温度、进液量及汽提比等参数进行不断优化将装置调整到最佳运行状态,采用3018固体脱硫剂对汽提脱硫装置中产生的高含H2S尾气进行全部回收,有效地防止了大气污染。     

Investigation of a Centrifugal Separator for In-Well Oil Water Separation

Abstract

A liquid–liquid centrifuge has been tested for possible application as a downhole method for separating crude oil from produced water. Centrifugal separators of various sizes (from 2- to 25-cm rotor diameter) have been built and operated over the past three decades at various US Department of Energy facilities. These units have several characteristics that make them attractive for downhole applications, including excellent phase separation, reliability in remote applications with >20,000 h of operation prior to maintenance, and the ability to handle high volumetric throughput with a very low residence time. In these studies, water-to-oil feed ratios of 10:1 to 1:19 were tested with a light Gulf of Mexico crude oil, and the separator operated efficiently for the full range of feed ratios. Air was added to the oil stream in one test to model the effect of gas in the oil. Air additions up to 20% of the feed flow rate (the maximum tested) did not have any impact on the performance of the separator. The separator also effectively processed a very viscous North Sea heavy crude oil. The heavy crude was used to determine the effect of higher temperatures on the performance of the separator. Increasing the temperature of the oil and water feed stream improved overall performance and decreased the concentration of oil in the water discharge stream.     

RESIDUUM HYDROTREATING/APPLICATION OF LIQUID- SOLID CHROMATOGRAPHY FOR THE STUDY OF HYDROTREATED PRODUCTS.

ABSTRACT

Iraqi reduced crude (above 350^°C) was hydrotreated in a fixed-bed reactor with commercial Ni-Mo-alumina catalyst. Reaction temperature varied from 320 to 400^°C over liquid hourly space velocity ranging from 0.82 to 2.6 h^?1. Hydrogen pressure was kept constant throughout all the experiment at 6.1 MPa with hydrogen/ oil ratio about 30D NL/L. Asphaltenes were precipitated from the reduced crude and hydrotreated products with 15 parts of n-pentane (by volume) to 1 part of sample. Then, the deasphaltened products were fractionated by liquid- solid chromatography for saturates, aromatics and polar- aromatics separation. The kinetic study of aromatics and polar- aromatics hydrogenation indicates that these reactions are well correlated with a second-order kinetics. The rate constants of aromatics and polar-aromatics hydrogenation were calculated. Finally, the apparent activation energy (Ea), enthalpy of activation (?H)^? and entropy (?S)^? were calculated for hydrogenation of aromatics and polar-aromatics of reduced crude during hydrotreating.     

DELAYED COKING OF HYDROTREATED REDUCED CRUDE

ABSTRACT

A laboratory coking unit was designed and constructed for an experimental study of the delayed coking process of hydrotreated Kirkuk reduced crude. The yield and analysis of coke, gases and liquid products were obtained for each experiment. The gas < C₄. and gasoline yield decrease by increasing Liquid hourly space velocity (LHSV) while the yields of kerosene and gas oil increase and no effect of LHSV on petroleum coke yield was observed, The specific gravity of gasoline, kerosene and gas oil decreases by increasing LHSV. The increase in LHSV (decrease in residence time) decreases the olefinic hydrocarbons of produced gas oil and fraction 350-450^°C. Sulfur content of produced coke and coking residue increases by increasing residence time while it changes slightly for kerosene and gas oil. By increasing the recycle ratio (RR), the yield of gas decreases while the coke yield increases. Sulfur content of gas oil and coking residue increases with an increase in the recycle ratio while it decreases for coke. Metals content of coke decreases with an increase in the recycle ratio and coke with accepted properties for aluminum anode manufacture could be produced when a recycle ratio of 1.4 was used.     

Performance Evaluation of Certain Commercial Hydrotreating Catalysts in a Pilot Plant Reactor

The performance of different hydrotreating catalysts was evaluated in a pilot plant trickle bed reactor using a feedstock collected from an industrial diesel hydrodesulfurization unit. The feed is a typical blend of straight run diesel fractions from crude distillation units, FCC cycle oils, heavy naphtha, etc. It contains 1.11 wt% of sulfur, 0.12 wt% of nitrogen, and 34.6 wt% of total aromatics. The catalyst samples evaluated in the present work are commercially available high activity new generation catalysts being used in many refineries for diesel hydrodesulfurization application. The experiments were carried out at a constant pressure of 40 kg/cm² and a constant H₂/oil ratio of 200 l/l. Experiments were performed to study the influence of reactor temperature and liquid hourly space velocity on product quality. The reactor temperature was varied from 320-360°C at different liquid hourly space velocities. The liquid hourly space velocity was varied from 1.0 to 2.5 h^-1 at different reactor temperatures. The feed and product samples hydrotreated in the pilot plant reactor were analyzed to determine their physical properties and measure sulfur, nitrogen, olefinic, poly-, di-, monoaromatic, and naphthenic hydrocarbons. Catalyst C was found to have the highest hydrodesulfurization activity among the catalysts studied. The hydrodesulfurization activity of catalyst A and catalyst B are similar. Catalyst D was found to have lower hydrodesulfurization and higher hydrodenitrogenation activity compared to catalyst C.     

选择性加氢脱硫催化剂RSDS-1的应用

为进一步考察催化剂RSDS-1的选择性加氢脱硫性能,中国石油化工股份有限公司长岭分公司对RSDS装置进行了催化裂化全馏分汽油加氢试验。结果表明,在反应器上床层平均人口温度260．1℃、床层平均温度270．8℃、空速425h^-1、氢油体积比422：1、反应压力1．40MPa的条件下,产品硫质量分数为69ug／g,研究法辛烷值损失07～2．0,质量满足欧Ⅲ标准的规定。     

人工神经网络在柴油馏分油加氢脱硫中的数学模拟

用３层前馈网络根据柴油馏分油性质、工艺条件对产品中硫的质量分数进行了预测,考察了原料油性质和工艺条件对加氢脱硫反应的影响。结果表明,工艺条件对ＨＤＳ反应深度影响的顺序为：反应温度〉空速〉氢对原料油体积比〉氢分压;原料油性质对反应深度的影响顺序为：密度〉５０％馏出点〉氮质量分数〉硫质量分数。     

非负载型催化剂上柴油深度加氢脱硫工艺条件研究

采用水热合成法制备了非负载型Ni-Mo-W催化剂并对其进行表征,研究催化裂化（FCC）柴油在该催化剂上的深度加氢脱硫过程,考察反应温度、反应压力、空速和氢油比等工艺条件对柴油深度加氢脱硫效果的影响,并与工业化NiMo/Al2O3催化剂的加氢活性进行对比。结果表明,在反应温度为340 ℃、反应压力为6.0 MPa、空速为1.5 h-1、氢油体积比为600的条件下,非负载型Ni-Mo-W催化剂可使胜华FCC柴油的脱硫率达到99.84%,脱氮率达到99.96%,与工业化NiMo/Al2O3催化剂相比,非负载型Ni-Mo-W催化剂具有更高的加氢活性。     

中国重油沥青资源的形成与分布

中国重油多具陆相成因特点:硫、微量元素及饱和烃含量均低.严重生物降解等稠变作用对甾萜化合物和多环芳烃均产生影响,并造成原油及族组分较大幅度的稳定碳同位素分馏.重质油藏多为新构造运动产物,与常规油藏有一定共生关系.中国重油沥青资源分布广泛,储量丰富.     

渣油选择性加氢脱硫技术研究

以中东高硫渣油为原料,从催化剂开发、工艺条件优化、催化剂级配及活性稳定性考察等角度深入研究并开发了渣油选择性加氢脱硫技术。结果表明：新开发的渣油选择性加氢脱硫催化剂(包括专用脱金属剂和专用脱硫剂)的加氢脱硫活性显著高于常规渣油加氢催化剂(包括相应的常规脱金属剂和常规脱硫剂);在加氢生成油硫含量相当的情况下,合适的氢分压、较低的体积空速、较高的氢油比以及较低的反应温度可以提高脱硫选择性;与常规渣油加氢脱硫技术相比,在脱硫率相当的情况下,新开发的渣油选择性加氢脱硫技术的反应温度低7℃,加氢生成油的残炭升高率为11.5%,加氢过程的氢耗降低率为7%～11%。     

CATALYTIC UPGRADING OF USED LUBRICATING OILS

ABSTRACT

Several commercial catalysts were tested for their activity for upgrading waste lubricating oils. The feedstock was vacuum distilled to remove the light and the heavy ends. Two trickle-bed reactors placed in series were employed, the top reactor contained a high surface area alumina and the bottom reactor the catalyst. A Ni-Mo-AI₂O₃ catalyst was selected for further study on the basis of its higner activity and activity maintenance. Several different hydrogen pressures, reactor temperatures, and liquid volume hourly space velocities were employed to arrive at the most optimum process conditions. This paper will discuss the effect of catalyst and process conditions on the product liquid color, viscosity, nitrogen, and sulfur content.