Visbreaking of heavy petroleum oil catalyzed by SO/ZrO solid super-acid doped with Ni or Sn

SO₄^2-/ZrO₂ solid super-acid catalysts (SZ) doped with Ni²⁺ or Sn²⁺ (Ni²⁺/SZ, Sn²⁺/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field. The visbreaking reactions were carried out at 240°C and 3–4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 : 0.05. The effect of water content on viscosity of heavy petroleum oil was also investigated. Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced from 0.319 Pa·s to 0.135 Pa·s for Ni²⁺/SZ and 0.163 Pa·s for (Sn²⁺/SZ) with visbreaking rates of 57.7% and 48.9%, respectively. After visbreaking, the saturated hydrocarbon content increased while aromatics, resin, asphaltene, sulfur and nitrogen content decreased. The presence of water was disadvantageous to visbreaking of heavy petroleum oil.     

100万 t/a 委内瑞拉超重油减粘裂化装置改造设计

辽河石化分公司减粘裂化装置原加工原料为辽河管输超稠油,本次改造采用了供氢热裂化技术,改造后适应加工委内瑞拉原油,装置投产成功,提高了辽河石化分公司减粘装置加工原料的适应性、加工能力和产品质量,并为委内瑞拉重油减粘工业试验打下良好基础.     

Visbreaking of heavy petroleum oil catalyzed by SO42-/ZrO2 solid super-acid doped with Ni2+ or Sn2+

SO₄²⁻/ZrO₂ solid super-acid catalysts (SZ) doped with Ni²⁺ or Sn²⁺ (Ni²⁺/SZ, Sn²⁺/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field. The visbreaking reactions were carried out at 240°C and 3–4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 : 0.05. The effect of water content on viscosity of heavy petroleum oil was also investigated. Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced from 0.319 Pa·s to 0.135 Pa·s for Ni²⁺/SZ and 0.163 Pa·s for (Sn²⁺/SZ) with visbreaking rates of 57.7% and 48.9%, respectively. After visbreaking, the saturated hydrocarbon content increased while aromatics, resin, asphaltene, sulfur and nitrogen content decreased. The presence of water was disadvantageous to visbreaking of heavy petroleum oil. __________ Translated from Petrochemical Technology, 2007, 36(3): 237–241 [译自: 石油化工]     

Liquid Phase RTD Studies in Sectionalized Bubble Column

The liquid phase backmixing has been reduced significantly by introducing horizontal perforated sieve plates into a 6.2 cm diameter and 77 cm height and in a 20 cm diameter and 90 cm height bubble columns. For the visbreaking operation of the petroleum residue, where the bubble column is used as soaker such a sectionalization has been suggested. The effect of the introduction of different gas quantities at various axial locations has also been studied to check the effect of increasing gas quantity formed in the visbreaking operation. The nonideality in the liquid phase backmixing has been studied by measuring liquid phase RTD and analysed by using one parameter dispersion model. A new parameter FP (flow parameter) has been defined and a correlation to predict liquid phase dispersion coefficient has been developed which covers the entire range of variables used in the present work.     

供氢剂辅助重油热改质技术研究进展

重油高黏度和高密度的特点给重油开采、集输和加工带来极大不便,一般都要先对其进行降黏处理。供氢热裂化是在传统减黏裂化基础上加入供氢剂,以改善减黏裂化加工深度不大、装置易生焦、产品安定性差等问题的一种高效重油改质降黏技术。文章首先介绍了重油管输技术基本类型,然后从供氢剂的供氢机理、供氢剂加入的作用、供氢剂的基本类型、供氢剂可供氢量的计算方法和供氢剂的运用等方面进行了综述。对于供氢剂的选择需要根据工艺条件和供氢剂性质等方面综合分析。指出在不生焦的前提下,尽可能提高改质苛刻度可有效提升重油改质效果,而影响生焦和抑制结焦的关键在于来自供氢剂的活泼氢能否及时封闭沥青质自由基。     

Kinetics of asphaltenes conversion during hydrotreating of Maya crude

The kinetics of asphaltene conversion was studied during the hydrotreating of Maya heavy crude oil. Experimental tests were conducted in a pilot plant at the following reaction conditions: total pressure of 70–100 kg/cm², liquid hourly space-velocity (LHSV) of 0.33–1.5 h⁻¹, and reaction temperature of 380–420 °C at a constant hydrogen-to-oil ratio of 5000 ft³/bbl. A commercial NiMo/Al₂O₃ catalyst was used in all experiments. Asphaltenes were precipitated from Maya crude and from hydrotreated products in a Parr Batch Reactor at 25 kg/cm² and 60 °C with n-heptane as solvent. Asphaltene hydrocracking data were used to estimate reaction orders and activation energy using a power-law model, and the average absolute error between experimental and calculated concentrations of asphaltenes was found to be less than 5%.     

The study on composition changes of heavy oils during steam stimulation processes

Using the heavy oils obtained from Liaohe oilfields in China, we have conducted the aquathermolysis reaction in laboratory at 240 °C. The results showed that Liaohe heavy oils have been undergoing visbreaking in the process of steam-drive and steam stimulation. After reaction with steam, the viscosity of the heavy oil was reduced by 28-42% and the amount of the saturated and aromatic hydrocarbons increased, while resin and asphaltene decreased. The gas partition chromatography showed that the accumulated amount of carbon numbers increased, after reaction, the accumulated amount of carbon numbers less than C₂₀ are 38.79-53.92%, and before reaction they are 13.30-20.92%. The results provided the basic data for heavy oil recovery by in situ catalytic method in production of heavy oil in oilfields.     

Production of gasoline range hydrocarbons from catalytic reaction of methane in the presence of ethylene over W/HZSM-5

The catalytic conversion of a methane and ethylene mixture to gasoline range hydrocarbons has been studied over W/HZSM-5 catalyst. The effect of process variables, such as temperature, percentage of volume of ethylene in the methane stream and catalyst loading on the distribution of hydrocarbons was studied. The reaction was conducted in a fixed-bed quartz-micro reactor in the temperature range of 300–500 °C using percentage of volume of ethylene in methane stream between 25 and 75% and catalyst loading of 0.2–0.4 g. The catalyst showed good catalytic performance yielding hydrocarbons consisting of gaseous products along with gasoline range liquid products. The mixed feed stream can be converted to higher hydrocarbons containing a high-liquid gasoline product selectivity (>42%). Non-aromatics C₅–C₁₀ hydrocarbons selectivity in the range of 12–53% was observed at the operating conditions studied. Design of experiment was employed to determine the optimum conditions for maximum liquid hydrocarbon products. The distribution of the gasoline range hydrocarbons (C₅–C₁₀ non-aromatics and aromatics hydrocarbons) was also determined for the optimum conditions.     

Rheological propertis of coal—oil mixture fuels

The rheological properties of coal—oil mixtures (COM) of a bituminous coal in four types of oil, grade 2, grade 4, light grade 6 and heavy grade 6, have been studied. Variables investigated were the coal concentration (0 – 60 wt.%), coal particle size (10 < d₅₀ < 40 μm), temperature (25 – 90 °C) and time effects (0 – 6 days).

Rheograms were obtained using the Ferranti-Shirley cone and plate viscometer. The COM was classified as a Newtonian fluid at coal concentrations up to 30 wt.% and as a Bingham plastic at higher values. The relative viscosity was found to increase rapidly with coal concentration, reaching 100 for a 60 wt.% of COM.

Both COM viscosity and yield stress decrease with increasing median particle size and decreasing slope of the particle size distribution. This effect is stronger at high solids concentrations.

The COM viscosity is much less sensitive to temperature than the base oil. The COM yield stress increases up to 350 Pa with increasing coal concentration, decreasing temperature and ageing.     

有机硅改性水性环氧固化剂的合成及表征

A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane （GPTMS） as a termination agent of adduct, which was synthesized by triethylene tetramine （TETA） and liquid epoxy resin （E-51）. The effects of the reaction temperature and time on the synthesis process were investigated experimentally. The particle size and the distribution of water dispersion of the curing agent were measured by dynamic light scattering（DLS）. The structure of the products was characterized by Fourier transform infrared spec-trometer （FTIR） and ^1H-nuclear magnetic resonance （^1H NMR）. The properties of the synthesized curing agent and the epoxy resin film cured by it were also measured. The results showed that the appropriate temperature for the synthesis of adduct was at 65-75℃ and the reaction time was 4-5h, and that the suitable reaction temperature of curing agent synthesis was 75-85℃ and the reaction time was 3-4h. When the mass ratios of GPTMS and acetic acid were 3%-5% and 5%-10% respectively, the hardness, water resistance and adhesion of the cured film were improved significantly.     

Feasibility study for reclamation of a secondary treated sewage effluent mainly from industrial sources using a dual membrane process

A feasibility study for reclamation of a secondary treated sewage effluent mainly from industrial sources (60%) in Singapore has been conducted using a dual membrane UF-RO process. The pilot system had a treatment capacity of 2 m³/h. The UF unit and RO unit were operated at 70–80% and 40% water recovery, respectively. Six-month run for the pilot was carried out to study the stability and fouling tendency of membranes.

The characteristics of the raw feed indicated that ammonia-N was consistently high at 30–50 mg/L. Very high fluctuations in iron (0.3–3.7 mg/L), turbidity (1–27.1 NTU) and TOC (3.2–56.7 mg/L) were observed. Nitrate was low at <0.2 mg/L. The results of the study showed that dosage of alum in the UF process significantly reduced organic foulants and phosphate scalants. The polymeric RO membrane could tolerate organics from industrial wastewater and performed >96% salt rejection at the end of the study after 6 months. The study concluded the dual membrane process was capable of reclaiming the sewage effluent mainly from industrial sources for industrial use.     

Kinetics of acid hydrolysis of olive felling residues

The kinetics of hydrolysis of olive tree felling residues with 1–4% HCl at temperatures between 110 and 140°C have been studied. The experimental results obtained were consistent with two successive first-order reactions by which cellulose residues are transformed into sugars, which in turn are converted into decomposition products. The kinetic constants of the process (per hour) were found to be related to the acid concentration used (C, in weight percent) and to the absolute temperature. According to the above-mentioned kinetic model, the experimental sugar concentrations obtained by hydrolysis were reproduced with errors less than 10–20%.     

Non-aqueous enzymatic solubilization of coal-derived materials

The utilization of enzymes in non-aqueous solvents was explored for the conversion of coal-derived materials to oil-soluble derivatives for use as fuels. A novel three-step process was developed:

1. (1) an initial low-severity conversion to a form that is soluble or dispersible in a polar solvent;

2. (2) formation of an alcohol substrate with a high activity for subsequent enzymatic processing;

3. (3) lipase-catalysed transesterification to a product that is soluble in hydrocarbon solvents.

The process was successful for the conversion of a first-stage liquefaction product from Wyodak subbituminous coal to an acylated product, about half of which is soluble in hexane and the remainder in toluene. Coals, humic acids and several other higher-molecular-weight coal liquefaction products, such as Chemcoal, and their derivatives inhibited the lipases, and thus the alcohol intermediates from these precursors were converted in 0–5% yields to acylated products.     

Characterization and utilization of hydrotreated products from the Whiterocks (Utah) tar sand bitumen-derived liquid

The bitumen-derived liquid produced in a fluidized-bed reactor from the Whiterocks tar sand was hydrotreated over a sulphided Ni-Mo/Al₂O₃ hydrodenitrogenation catalyst in a fixed-bed reactor. The process variables studied were temperature (617–680 K), pressure (11.0–17.1 MPa) and liquid hourly space velocity (0.18–0.77 h⁻¹). The feed and the hydrotreated liquid products were analysed by gas chromatography-mass spectrometry analyses. The compounds identified in the bitumen included isoprenoids; bicyclic, tricyclic, and tetracyclic terpenoids; steranes; hopanes; and perhydro-β-carotenes. Normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. Comparison of the compounds identified in the bitumen and the bitumen-derived liquid indicated that the dealkylation of long alkyl side chains 0to form - and isoolefins and the cleavage of alkyl chains linking aromatic and hydroaromatic clusters were the dominant pyrolysis reactions. Monoaromatic hydrocarbons were the predominant aromatic species in the hydrotreated product. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated that these fractions would be suitable for use as diesel fuels.     

Solid catalysts for wet oxidation of nitrogen-containing organic compounds

Several solid catalysts (Co₃O₄/γ-Al₂O₃, Fe₂O₃/γ-Al₂O₃, Mn₂O₃/γ-Al₂O₃, Zn–Fe–Mn–Al–O, Pt/γ-Al₂O₃, Ru/CeO₂, Ru/C) have been prepared and used to remove N-containing organic contaminants while processing toxic and hazardous industrial waste waters using wet oxidation by air (WAO). The autoclave tests of catalysts were done to reveal the main advantages of catalysts in water presence at high pressures and temperatures. Catalyst activity was determined with regard to oxygen interaction with model mixtures (water–organic contaminant: acetonitrile, carbamide, dimethyl formamide, or multi-component mixture of aliphatic alcohols). Activity tests were done in a static reactor under ideal mixing regime. Reagents and products were monitored using gas chromatograph Cvet-560, Millichrom-1 HPLC, and routine chemical analysis. Optimum process conditions for the best catalyst (Ru/graphite-like carbon) are as follows: partial oxygen pressure – 1.0 MPa, temperature – 473–513 K. At 0.5–5.0 MPa total pressure and 433–523 K catalysts show high water-resistance and high activity level (residual content of toxic compounds is less than 1%, and no NO_x and NH₃ are detected). There are no legal restrictions on catalysts operation, since they are harmless to environment.     

重质石油烃利用技术-重质烃气化-裂解集成工艺的模拟研究

我国是一个石油资源紧缺的发展中国家,石油供给高度依赖于世界石油市场. 世界原油资源的重质化和对轻质产品需求的增加,使重质石油烃利用技术成为我国能源和石化工业的一个重要课题. 现有的重质石油烃利用技术中,减粘裂化、焦化、催化裂化和加氢转化仍然是最主要的技术手段. 同时,气化和裂解制烯烃也显示出良好的技术潜力. 本工作提出的重质石油烃气化-裂解集成工艺利用燃烧裂解结焦为气化和裂解过程提供热量,同时产出合成气和部分低碳烯烃. 模拟研究显示,通过调整O2和水蒸汽流量可实现对气化-裂解温度的控制,在近零焦炭添加量的情况下可同时获得合成气和低碳烯烃,可在控制反应停留时间的条件下获得产物中烯烃的最大组成.     

Methane conversion to C2 hydrocarbons and hydrogen in atmospheric non-thermal plasmas generated by different electric discharge techniques

Methane conversion to C₂ hydrocarbons and hydrogen has been investigated in a needle-to-plate reactor by pulsed streamer and pulsed spark discharges and in a wire-to-cylinder dielectric barrier discharge (DBD) reactor by pulsed DC DBD and AC DBD at atmospheric pressure and ambient temperature. In the former two electric discharge processes, acetylene is the dominating C₂ products. Pulsed spark discharges gives the highest acetylene yield (54%) and H₂ yield (51%) with 69% of methane conversion in a pure methane system and at 10 SCCM of flow rate and 12 W of discharge power. In the two DBD processes, ethane is the major C₂ products and pulsed DC DBD provides the highest ethane yield. Of the four electric discharge techniques, ethylene yield is less than 2%. Energy costs for methane conversion, acetylene or ethane (for DBD processes) formation, and H₂ formation increase with methane conversion percentage, and were found to be: in pulsed spark discharges (methane conversion 18–69%), 14–25, 35–65 and 10–17 eV/molecule; in pulsed streamer discharges (methane conversion 19–41%), 17–21, 38–59, and 12–19 eV/molecule; in pulsed DBD (methane conversion 6–13%), 38–57, 137–227 and 47–75 eV/molecule; in AC DBD (methane conversion 5–8%), 116–175, 446–637, and 151–205 eV/molecule, respectively. The immersion of the γ-Al₂O₃ pellets in the pulsed streamer discharges, or in the pulsed DC DBD, or in the AC DBD has a positive effect on increasing methane conversion and C₂ yield.     

稠油化学降粘法概述

综述了稠油开采的常用方法（加热法、掺稀油法、稠油改质降粘法和添加化学药剂降粘法）,着重介绍了添加化学药剂降粘法（催化降粘、加碱降粘、加表面活性剂降粘、加降凝剂降粘、加油溶性降粘剂降粘）,并阐述了它们的作用机理及其存在的问题,指出了今后降粘剂的发展趋势。     

A method for obtaining thymol by gas phase catalytic alkylation of m-cresol over zinc aluminate spinel

The gas-phase catalytic alkylation of m-cresol with isopropanol on ZnAl₂O₄ catalysts of different properties has been studied. The reactions were carried out in a continuous process at atmospheric pressure in the temperature range of 473–583 K. Both, O- and C-alkylated products were obtained at lower temperatures while at higher temperatures thymol was the main product of the reaction. According to the elaborated method thymol can be efficiently obtained with selectivity reaching up to 88.4% at an m-cresol conversion of 78.2%.     

A novel conceptional process for residue catalytic cracking and gasoline reformation dual-reactions mutual control

Based on the subsidiary riser FCC (SRFCC) process for gasoline reformation [Y.H. Bai, J.S. Gao, S.C. Li, C.M. Xu, Petrol. Process. Petrochem. (China) 35 (2004) 17–21, J.S. Gao, C.M. Xu, Y. Mao, et al., Petrol. Refin. Eng. (China) 35 (2005) 7–9], a novel conceptional process for residue catalytic cracking and gasoline reformation dual-reactions mutual control (DMC) was proposed and relevant experimental researches were carried out in a Technical Pilot Scale Riser (TPSR) FCC apparatus. The goals of DMC were to improve product quality and increase desirable product yield in residue catalytic cracking as well as in FCC gasoline upgrading. The experiments showed that the decrease of temperature difference between feedstock and regenerated catalysts in DMC by directly leading the cooled regenerated catalysts into riser reactor or feeding gasoline into riser reactor in vapor phase could decrease the amount of dry gas and coke and obtain a better quality of upgraded gasoline. Moreover, the spent catalysts still retaining high level of activity could be recycled to the base of the main riser reactor treating heavy oil and mixed with regenerated catalysts in DMC, it allows residue catalytic cracking to operate at high catalyst-to-oil ratio and the relatively low inlet catalysts temperature. The experimental results also showed that the mixed catalysts could improve the product selectivity in residue catalytic cracking, especially for light oil (gasoline and diesel). In addition, compared with the routine RFCC, the product distribution from the residue catalytic cracking in DMC contains more liquid products, less dry gas, and a better gasoline quality.