Characteristic Properties of a Locally Produced Paraffinic Oil and Its Suitability as a Heat-Transfer Fluid

The thermo-physical properties of a paraffinic mineral oil produced in a local refinery were experimentally determined over a wide temperature range of 30-360°C to determine its suitability for use as a heat-transfer fluid. The effect of temperature on the physical characteristics of the oil and two synthetic organic heat transfer fluids was evaluated at high temperatures (180-360°C). Comparison of the main properties of the mineral oil with other heating fluids revealed its compatibility with synthetic organic fluids, some other paraffinic and mineral oils employed as heat-transfer fluids. The study further confirmed that the investigated mineral oil which was produced locally can be used to replace the imported synthetic oils in heat transfer systems operating at a maximum application temperature of 310°C, as indicated by the thermal stability test.     

Characteristic Properties of a Locally Produced Paraffinic Oil and Its Suitability as a Heat-Transfer Fluid

Abstract

The thermo-physical properties of a paraffinic mineral oil produced in a local refinery were experimentally determined over a wide temperature range of 30–360°C to determine its suitability for use as a heat-transfer fluid. The effect of temperature on the physical characteristics of the oil and two synthetic organic heat transfer fluids was evaluated at high temperatures (180–360°C). Comparison of the main properties of the mineral oil with other heating fluids revealed its compatibility with synthetic organic fluids, some other paraffinic and mineral oils employed as heat-transfer fluids. The study further confirmed that the investigated mineral oil which was produced locally can be used to replace the imported synthetic oils in heat transfer systems operating at a maximum application temperature of 310°C, as indicated by the thermal stability test.     

DEEP DESULPHURISATION OF A DIESEL BLEND IN A PILOT PLANT TRICKLE BED REACTOR

A pilot plant investigation was conducted to study the influence of hydrotreating conditions on conversion and characteristics of diesel blend and to determine the severity of operating conditions required to meet the proposed product specifications for diesel fuel in India. A typical diesel blend derived from various refinery streams with sulphur content of 2·06 wt% was hydrodesulphurised over a commercial NiO-MoO₃/Al₂O₃ catalyst in a pilot plant trickle bed reactor. The experiments were conducted at 300-370°C, 30-50 kg/cm², 2·0 3·0 hr^-1 liquid hourly space velocity and constant H₂/oil ratio of 185 m³/m³. The data showed that the diesel blend could be hydrotreated to meet revised product specifications of 0·25 wt% sulphur, 46 cetane number by increasing the severity of operation. The cetane number and aromatic saturation were limited by thermodynamic equilibrium at temperatures above 360°C. The influence of temperature was found to be more pronounced than that of pressure in the range of operating conditions studied.     

RECOVERY OF ASPHALTENES FROM TAR SAND BY SUPERCRITICAL FLUID EXTRACTION

Many non-oil producing countries are enriched with other sources of energy, for example tar sand, oil shale, coal, biomass, and uranium, that are not fully utilized. Supercritical fluid extraction (SFE) of tar sand was carried out in a batch autoclave at different temperatures. Extracts recovered from SFE were fractionated into oils, asphaltenes, preasphaltenes and gases by solvent extraction. The highest yield) of SFE (24.3 wt % dry basis) from tar sand was obtained with n-pentane/benzene (1/1, v/v') mixture at 655 K. Comparison of the amount of n-alkanes (C1-C4) evolved at 585 K and 685 K shows that the amount of methane is significantly increased at 685 K whereas the amount of C4 alkane is reduced. At 685 K, hydrogen and methane represent 45·1 vol % of the gases evolved from the SFE. The yields of C1-C3 alkane hydrocarbons were higher for supercritical fluid extracts at 685 K as compared to those obtained at 585 K. The quantity of olefines (C₂H₄ + C₃H₆) was found between 5·1 and 10·1 vol %.     

A Comprehensive Evaluation of High Viscous Crude Oil from Shuguang No. 1 Zone of Liaohe Oil Field

The high viscous crude oil from Shuguang No. 1 zone of Liaohe oil field has the characteristics of high density (ρ₂₀ = 0.9977 g cm^-3), great viscosity (ν₁₀₀ = 1223.9 mm² s^-1) and high pour point (48°C), which are similar to those of the residue distillation of general crude oils. It contains no gasoline distillation and the diesel oil fraction yield is just 7.19%. It is often used as fuels after emulsification. But this oil is so vicious that it cannot be atomized uniformly and burned fully. In order to make full use of it, this kind of high viscous crude oil has been evaluated comprehensively and the properties of its various distillations are analyzed respectively. The results indicate that this crude oil contains less wax, but more resins and asphaltene, which belongs to low-sulfur naphthene-base crude oils and it is the suitable material to produce high-quality paving asphalt. Based on its characteristics, the optimum processing scheme is put forward and the high-quality paving asphalt is produced by using the distillation higher than 350°C.     

Study on Improving Oxidation Stability of Catalytically-Cracked Diesel Oil

In this article, oxidation stabilities of catalytically-cracked diesel oil extracted with several solvents were studied respectively. The experimental results showed that double-solvent extraction was the better method than others, in which furfural containing transition metal ion was used as the first extraction solvent and the 95% ethanol solution was the second extraction solvent. During the course of accelerated storage test, the amount of sediment was reduced from 27.56 mg/100 mL to 0.43 mg/100 mL, and met the requirement of premium grade diesel oil. Under the experimental condition: shaking time of 3 min, the volume ratio of solvent to oil of one and operating temperature 30°C, the extraction result is most satisfied. The color and existent gum reached the standard of premium grade diesel oil. The removal rate of sulfur was up to 74.5%, the removal rate of nitrogen 93.8%. The cetane number of catalytically-cracked diesel oil was enhanced from 37.3 to 51.2. The oxidation stability was improved greatly after being treated.     

Dispersed Phases and Dispersed Phase Deposition Issues Arising in Asphaltene Rich Hydrocarbon Fluids

Our interest in the phase behavior of asymmetric, industrial organic fluids focuses on understanding the impact of phase behavior, particularly solid phase behavior, on flow assurance and other reservoir fluid management and production issues, as well as on heavy oil partitioning processes in upgrading operations. Recent developments in X-ray view cell technology allow us to examine the phase behavior of fluids containing large mass fractions of asphaltenes, and dispersed organic and inorganic solids, in a routine manner. Over the past three years we have been preparing detailed phase behavior maps, including phase densities, for the model system Athabasca Bitumen Vacuum Bottoms (ABVB), a 525+ °C fraction containing 32 wt% pentane asphaltenes + pentane, heptane and dodecane using a variable volume X-ray view-cell. The X-ray view-cell experimental program focused on the temperature range, 100 to 340°C, and the pressure range, 0.1 to 30 MPa. The mixtures exhibit complex but reversible multiphase behaviors. Over much of the phase space solids, if present, remain dispersed. Over a narrow range of conditions the solids tend to settle. In addition, adherent deposits, including solids and viscous liquids, are observed at temperatures less than 200°C over a broad range of conditions.     

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.     

THE EFFECT OF VISBREAKING CONDITIONS ON THE STABILITY OF SOME IRAQI LONG RESIDUES

A study has been done to investigate the change in the stability of residue during thermal process (visbreaking) at different cracking severity using flocculation ratio method. For this purpose, three long residues (350°C+) of different crude oils were used. The obtained results were discussed as a function of reaction temperature and residence time. Moreover, the stability was correlated with the nature and chemical composition of the feedstock.We observed that the intermediate paraffinic base feedstock (type A) was more stable than the other two asphaltenic base (Types B & C) when visbreaking temperature was 460°C. At higher temperatures, a sudden and large decrease in the stability of type A visbroken products was observed while only a gradual decrease in the stability of the other two products was noticed when visbreaking process was carried out at the same operating conditions.     

Thermal Hydrocracking Kinetics of Chinese Gudao Vacuum Residue

The thermal hydrocracking kinetics of Chinese Gudao vacuum residue was studied in a batch autoclave reactor. The temperature ranged in 390-435°C and the initial hydrogen pressure was 7.0 MPa at 20°C. Ammonium phosphomolybdate (APM) in its dispersed phase was the catalyst. The reaction products, gas, naphtha, atmospheric gas oil (AGO), vacuum gas oil (VGO) and coke, were separated during and after experiments, and their yields vs. reaction time were obtained, for four reaction temperatures: 390, 405, 420, and 435°C. The activation energy was calculated from a traditional kinetic model to be 218.6 kJ/mol. A new kinetic model was proposed in this work that allows for the calculation of activation energy with a minimum number of three tests, each at a different temperature. This is comparable to the traditional model which requires a minimum of 12 tests; a minimum of four tests for one temperature and a minimum of three temperatures. The activation energy calculated from the new model with four tests is 229.6 kJ/mol, only 5% greater than that obtained from the traditional model. The reaction rate constants obtained from this model are also consistent with those from the traditional model.     

A STUDY ON THE EFFECT OF PREPARATION PARAMETERS ON THE CATALYTIC PERFORMANCE AND ACTIVE COMPONENTS OF A NEW TYPE HYDRODESULFURIZATION CATALYST

The effects of the impregnating conditions on the contents of the active components of a new type hydrodesulfurization (HDS) catalyst have been studied by ICP technique in this paper. Meanwhile, the effects of the activation temperature, the activation time and the calcining temperature on the catalytic properties of the CoMo/(TiO₂ + Al₂O₃) catalyst have also been studied. The results show that at the given hygroscopicity of the support, the contents of the Co and the Mo, both of which are the active components of the catalyst, change linearly with the changes of the concentrations of the solvents in the impregnant. When the catalyst is impregnated at 40°C for 2 h, the contents of the active components reach the maximum values. The calcining temperature sharply affects the dispersed state of the active components on the surface of the support. When calcined at 500°C for 2 h, this HDS catalyst obtains the best catalytic activity. Even when the catalyst has been calcined at 600°C for 3 h, its activity is still good, which indicates that the heat resistance of this new type catalyst is satisfactory.     

内蒙古油砂沥青热转化前后化学结构的变化规律

 采用核磁共振和红外光谱分析方法对内蒙古3种油砂沥青及其流化热转化后的液体产品的化学结构进行了研究。通过用改进的Brown-Ladner 法计算了油砂沥青及热转化后得到的液体产品的平均分子结构参数,发现热转化得到的液体产品平均分子结构参数发生了明显的改变。相对于原料油砂沥青,热转化液体产品的芳碳率f_A略有增加、环烷碳率f_N大幅度增加,而烷基碳率f_p则明显减少,并且总环数R_T从6.10~8.64下降到2左右,芳香环数R_A从3.13~6.10下降到1左右,环烷环数R_N也从2.22~3.42下降到1左右。3种不同性质油砂沥青的平均分子结构参数变化趋势相同,均归因于油砂沥青热转化过程中多环芳烃的聚合和长链烷烃侧链的断裂。     

HYDROZEN TRANSFER HYDROCRAKING OF C.PROCERA UNDER AMBIENT PRESSURE CONDITIONS TO GET VALUE ADDED CHEMICALS AND FUELS

Biomass is renewable source of energy while the reserves of petroleum arc being depleted. The latex of a potential petrocrop, Colotropis procera, a lalicifcr, arid-plant which is rich in hydrocarbon type triterpene compounds etc. was found lo be a better feed slock for thermal hydrocracking as compared to whole plant biomass inlcrms of liquid product yield. Studies of chemical reaction dynamics of the thermal cracking of latex at 200-400°C showed that the process should be termed as hydrogen-tranfer (H-T) hydrocracking of latex under ambient pressure conditions. The hydrogen rich cracked trilcrpenoids act as the H-donors in this process, where nascent hydrogen atoms and free radicals chemically plug the cracked moities to stabilise these. Latex was also coagulated and the H-T hydrocracking of the feedstock coagulum gave a higher yield of cracked oil in comparision lo that from the dried latex. A model triterpene compound, ursolic acid has been subjected to H-T hydrocracking to understand the process of hydrocracking of latex under similar conditions and it was found that triterpencs on H-T hydrocracking produced only liquid and gaseous products and no solid char. The temperature for hydrocracking of latex has been optimized to 350°C and molecular sieve was round to catalyse the H-T Hytrocraking process to yield more liquid product The distillation range of cracked latex on(CLO)Obtained from H.T Hytrocracking of C procera Latex indicated that it can be used as fuel. Moreover CLO resembled diesel fuels and was predominantly paraffinic in nature as characterised by NMR and FTIR spectral analysis. A process has been recommended for gelling value added fuels and chemicals from C. procera latex.     

ACETALDEHYDE FROM CARBON MONOXIDE AND CHLOROMETHANE

Acetaldehyde (CH₃CHO) is the major oxygenated product of the thermal reaction of carbon monoxide and chloromethane under reaction conditions, i.e., between 600 °C and 700 °C, and between 0.1 MPa and 1 MPa. The reaction conditions have a significant effect on the formation of the products.     

Oligomerizing Olefins in Light Coke Gasoline to Diesel

We prepare a catalyst for FCC gasoline polymerizing to produce diesel oil, which uses non-noble metal Ni as the main active component; here mesopore γ-Al₂O₃ is used as the carrier. The effects of mass fraction of active components and the condition of preparing were investigated simultaneously. The results show that mass fraction of the main active component is 8%, soakage time is 6 hr, and the roasting temperature is 500°C to roast for 4 hr, which are better conditions for preparing the catalyst. Under the condition of a reaction temperature of 210°C, reaction pressure is 3.0 Mpa, space velocity is 1.0 h^-1, and volumetric percent of diesel is 42.0%, which meet a criterion of -35^# diesel. At the same time we study the stability and regeneration of the catalyst with good results.     

STUDIES ON SLUDGE FROM STORAGE TANK OF WAXY CRUDE OIL PART - I : STRUCTURE AND COMPOSITION OF DISTILLATE FRACTIONS

Tank bottom sludge from storage tanks of Bombay High crude oil deposited during ten years have been studied. The yield of the sludge is approximately 0.1% wt. of the crude oil through-put. The residue boiling above 500°C amounts to over 50%. The distillate fractions collected at 50°C intervals have been analysed extensively and compared to fractions from whole crude of same boiling range. The sludge distillate are distinctly more paraffinic in nature.     

Application of “Micro-demolition Atomization” Theory in Feedstock Atomization for RFCCU

Based on the “Micro-demolition Atomization” theory of emulsified heavy oil combustion, the heavy oil catalytic cracking feedstock was emulsified by compound nonionic surfactant. The water was dispersed uniformly into oil with drops about 1-5 µm, and could be formed stable water-in-oil emulsion with oil. After being in contact with high temperature regenerated catalyst, the emulsified feedstock was atomized demolishedly, which changed atomization mode and reduced the diameters of liquid drops to about 5 µm, enhanced the effect of catalytic cracking reaction, improved the selectivity of coke and increased the recovery of light oil. The pilotscale test result of catalytic cracking showed that, compared with unemulsified feedstock under the same conditions, the recovery of light oil was increased by 2-3%, the yield of coke was reduced by 0.5-1.0%, and the yield of dry gas was reduced by 0.5-1.5%,respectively. The application of the “Micro-demolition Atomization” theory in the feedstock atomization of the heavy oil catalytic cracking would change traditional atomization mode, and affect the catalytic cracking of the heavy oil significantly.     

RECOVERY OF ORGANIC MATTER FROM GREEN RIVER OIL SHALE AT TEMPERATURES OF 400°C AND BELOW

Experiments to recover organic matter from Green River oil shale in high yields at temperatures of 400^°C and below are described. Three different recovery procedures are discussed: 1) experiments wherein liquid organic materials were extracted at atmospheric pressure and temperatures below 75^°C by solvents of different strengths, 2) autoclave experiments where liquid organics were recovered by heating the shale with a variety of solvents at temperatures between 300 and 400^°C and pressures between 5 and 32 MPa, and 3) an autoclave experiment where liquid organics were recovered by heating shale in an argon atmosphere for 1 hour at 400^°C. The liquid organic materials recovered in these experiments represent from four to 90 weight percent of the total organic material in the shale. The liquid organic materials have an average molecular weight of between 500 and 600 amu as compared to a typical shale oil that has an average molecular weight of 300 to 350 amu. Elemental analyses show that the liquid organic materials contain high percentages of hydrogen and nitrogen, as does shale oil. Moreover, the liquid organic materials also contain much larger concentrations of oxygen-containing compounds than shale oil. The experimental results suggest the possibility of developing a new process for recovering both organic and inorganic material from Green River shale.     

Clarified Oil from Fluid Catalytic Cracking as an Additional Source of Group II Base Oil Components

Abstract

Clarified oil (CLO) from a commercial fluid catalytic cracking unit was subjected to solvent extraction followed by solvent dewaxing and adsorption chromatography to analyze its various components for different end-use applications. The clarified oil was first solvent extracted using N-methyl pyrrolidone (NMP) to produce paraffinic rich raffinate (68.9 wt% yield). The raffinate thus obtained was dewaxed using methyl isobutyl ketone (MIBK) to get an oil of pour point 0°C. This dewaxed oil was then subjected to adsorption chromatography to determine group II base oil potential through yield v/s viscosity index (VI) curve. The results revealed that clarified oil has an actual potential of around 27.1 wt% of group II base oil components, suggesting that clarified oil can be used as an additional source of feed for production of group II base oil. This article also describes the potential of other components in clarified oil such as slack wax (24.2 wt%), aromatics (31.1 wt%), and low VI oil (17.6 wt%).     

AN EXPERIMENTAL STUDY OF THE EFFECT OF PARAFFINIC SOLVENTS ON THE ONSET AND BULK PRECIPITATION OF ASPHALTENES

Asphaltene onset concentration and bulk deposition were measured for a typical live reservoir oil titrated with n-C₆H₁₄, n-C₅H₁₂, n-C₄H₁₀, C₃H₈, C₂H₆, CH₄ and CO₂ at 100° C (212 ° F) and 29.9 MPa (4340 psia). The concentration of titrant at asphaltene onset was observed to decrease approximately in a linear fashion with decreasing molecular weight of the paraffinic solvent; CH₄ did not induce any asphaltene precipitation. Bulk deposition experiments were performed using a solvent: oil volume ratio of 10:1; the results indicated that the weight percent of asphaltenes precipitated increased exponentially with decreasing molecular weight of the paraffinic solvents. More importantly, the asphaltene molecular weight showed a maximum for n-C₄H₁₀ precipitated asphaltenes. Possible explanations for this unusual result are presented.