Numerical Analysis on the Three-Phase Flow With Condensation of CH₄, H₂O and n-C₉H₂₀
FEI Ji-You, LI Yu, LI Liang
2008, 21 (3): 1-4.
Abstract ( ) PDF ( 2974KB ) ( ) 　　
A numerical model was developed to simulate the three-phase flow with condensation of the mixture of methane (CH₄), water vapor (H₂O) and nonane (n-C₉H₂₀). Using this model the condensing flow of methane with saturated water vapor and nonane vapor in a convergent-divergent nozzle were investigated. The result shows that in this three-phase flow, the nucleation position of nonane vapor is 0.05 m downstream of that of water vapor, which is a result of the different thermo-physical properties of H₂O and n-C₉H₂₀. With the inlet pressure rises, the supercooling leading to nucleation, the nucleation rate, the number of liquid droplets and the mass fraction of liquid phase decrease for both water vapor and nonane vapor. The result also indicates that in the three-phase flow, the latent heat released during the condensation processes of water vapor and nonane vapor changes each other's supercooling. As a result the condensation processes of water vapor and nonane vapor are weakened.
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Particle Velocity Distribution in the Bubbling Fluidized Bed
YANG Kuan-li， WANG Qi-cheng， ZHANG Kai,DAI Wei-di，JIANG Jian-chun
2008, 21 (3): 5-8.
Abstract ( ) PDF ( 3355KB ) ( ) 　　
 
Radial velocity distributions of two kinds of glass beads, belonging to Geldart type B classification, were investigated at different axial sections in the bubbling fluidized bed with an inner diameter of 0.185 m under different superficial gas velocities. Local particle velocities were measured by using the PV-5A fiber-optical probe. The experimental results indicate that the radial distribution of particle velocities in the bed bottom zone is irregular, where the design of the distributor is dominated. When the axial section is far from the distributor, the particle velocities are higher in the center than those near the wall within the bed, which becomes obvious with increasing superficial gas velocity. Meanwhile, there exists a transitional zone between the above two zones, where the effect of the distributor tends to be weakened. This leads that the radial distribution of particle velocities is regular. Moreover, the amplitude of particle velocity at the same axial position changes sharply with an increase of superficial gas velocity.
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Application of Polyether Demulsifier TA1031 Modified by Nano-Al₂O₃ Sol
SUN Zheng-gui
2008, 21 (3): 9-12.
Abstract ( ) PDF ( 1985KB ) ( ) 　　
In order to improve the performance of macromolecule polymer demulsifier and enlarge the range of application of nano-material, the nano-Al₂O₃ and macromolecule polyether demulsifier TA1031 were grafted by sol-gel method with Al₂(SO₄)₃ and NH₃·H₂O. The Nanometer modified demulsifier was analyzed by FTIR, SEM, rotational viscometer and interfacial tensionmeter. The results show that applying nano-Al₂O₃ to crude oil polymer demulsifier would greatly improve the performance of the original demulsifier. When the mass ratio of aluminium oxide and TA1031 was 1∶10, the performance of the nanometer modified demulsifier is better, and the ratio of demulsification would be improved about 20%~25%. The time of demulification and dewatering would be greatly shorten, and the demusification mechanism and formation mechanisms of nanometer modified demulsifier was preliminary analysised.
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Synthesis, Characterization and Catalysis Performance of Lanthanum Composite Mesoporous Oxide
SONG Wei-ming, DENG Qi-gang
2008, 21 (3): 13-15.
Abstract ( ) PDF ( 3032KB ) ( ) 　　
Lanthanum oxide/dodecyl sulfate mesoporous material (LaOS) was synthesized by hydrothermal method with SDS as template and ethylenediamine as medium. The experimental results indicate that the material had the ordered mesoporous pore structure when n(La)/n(SDS)/n(CO(NH₂)₂)/n(H₂NCH₂CH₂NH₂)/n(H₂O)=1.0∶1.0∶0.6∶1.0∶200, stirring at 80 ℃ and 4 h using several measurements such as XRD, IR，TG/DTA,N₂ adsorption-desorption .The results indicate that the material had the medial pore structure with average pore diameter of 2.6 nm and the specific surface area of 182 m²/g. The LaOS materials were used as catalysts in the ethoxylation reaction. The results show that the material was highly catalytic activity. Experiment indicates that the optimum processing parameters are :120 ℃, 0.5 MPa,mass fraction of 10% catalyst (LaOS) and average reaction rate of epoxy ethane is 3.7 mol/(mol·h). And narrowed chain distributions of octanol polyoxyethlene were formed in the presence of LaOS catalyst.
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Preparation and Catalytic Properties of Fe₂(SO₄)₃/Bentonite Solid Acid Catalyst
LI Ke-jing，JIN Hai-bo， ZHAO Zhen
2008, 21 (3): 16-20.
Abstract ( ) PDF ( 3405KB ) ( ) 　　
Fe₂(SO₄)₃/bentonite solid acid catalyst was prepared, which the bentonite was disposed using H₂SO₄ and the catalyst carriers dipped with Fe₂(SO₄)₃ solution. The influence of H₂SO₄ mass fraction, Fe₂(SO₄)₃ concentration and activation temperature on the Fe-B/SO₄^2- catalytic performances through isopropylation reaction of naphthalene was investigated. The suitable preparing technology conditions were obtained as follows: H₂SO₄  mass fraction is 10%, Fe₂(SO₄)₃ concentration is 0.08 mol/L and activation temperature is 200 ℃. Meanwhile, the Fe₂(SO₄)₃/bentonite catalyst was characterized by XRD, BET, TG and SEM methods, respectively.
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Synthesis and Characterization of Methylacrylic  Acid Polyethylene Glyco1 Ester
ZHU Wei, YANG Jun, CHEN Wei
2008, 21 (3): 21-23.
Abstract ( ) PDF ( 2359KB ) ( ) 　　
Methylacrylic acid polyethylene glyco1 ester was synthesized by using methylacrylic acid and polyethylene glycol 400.The factors such as dosage of polymerization retarder,reaction time,reaction temperature,acid glycol molar ratio and the dosage of catalyst on the yield of product was investigated, and the product was analyzed by using 1HNMR and IR.The results show that the yeild of product reached 88.4% at optimal condition of temperature was 100 ℃, reaction time was 8 h, acid glycol ratio was 3∶1. And the mass fraction of opposite-methyl-phenylsulfon was 2.5%.
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Degradation of Oilfield Wastewater by High Voltage Pulsed Discharge Technology
WANG Jia－lin, CHEN Chun－mao, GUO Shao－hui*
2008, 21 (3): 24-28.
Abstract ( ) PDF ( 2736KB ) ( ) 　　
High voltage pulsed discharge (HVPD) technology was utilized to degrade oilfield wastewater in order to improve its biodegradability. Water samples before and after treated were analyzed by GC-MS to investigate the mechanism of biodegradability improvement. The experimental results show that the BOD5/COD of oilfield wastewater can be improved from 0.066 to 0.33 after 10 minutes by HVPD treatment, the biodegradability of oilfield wastewater was improved effectively. The optimal operational parameters of this experimental are : the pulse voltage peak value is ±26 kV, the air flow rate is 0.50 m3/h and the pulse frequency is 150 Hz.The GC-MS analytic results indicate that the ploynuclear compounds and long chain alkanes and aromatic Hydrocarbons in oilfield wastewater are degraded to low relatively molecular pollutants after HVPD technology treatment.
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The Application of the Acidic Ionic Liquid of ［(CH2)4SO3HMIm］ TSO in Thiophene-Based Oxidative Desulfurization
WANG Li, WU Xiao-jun, GUI Jian-zhou*, LIU Dan, 
2008, 21 (3): 29-31.
Abstract ( ) PDF ( 1779KB ) ( ) 　　
Without any organic solvents and halide, the oxidation of thiophenic sulfur into sulfone which would be extracted by the ionic liquid catalyzed by Na2WO4·2H2O with mass fraction of 30% hydrogen peroxide in acidic ionic liquid ［(CH2)4SO3HMIm］TSO was investigated. Effects of temperature, reaction time and amount of catalyst on the reaction of oxidative desulfurization were also investigated. The optimal reaction conditions are as follows: 3 mL oil sample (500 μg/g sulfur content), the ratio of 40∶1 for n(IL)/n(Na2WO4·2H2O), 0.7 mL hydrogen peroxide, reaction temperature of 333 K and reaction time of 2 h. And the rate of desulfurization is 97.4% under this condition.When the reaction was completed, diesel oil and catalyst could be separated by simple decantation. The catalyst could be recycled 4 times without obvious change in catalytic activity.
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Three Dimensional Quantitative Structure Activity Relationship of 
YANG Guo-chen, TONG Jian-bo, LIU Shu-ling
2008, 21 (3): 32-37.
Abstract ( ) PDF ( 2000KB ) ( ) 　　
The three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) was used to describe the structures of 1,2-diarylcyclopentenes analogous as cyclooxygenase-2 (COX-2) inhibitors. Quantitative structure-activity relationship (QSAR) between the 3D-HoVAIF parameters and activity of 1,2-diarylcyclopentenes analogous were generated by partial least square regression (PLS). The estimation stability and generalization ability of the model was strictly analyzed by both internal and external validations. The correlation coefficient of established PLS model, leave-one-out (LOO) cross-validation(CV), prediction values versus experimental ones of external samples were R2cum of 0.820, Q2cum of 0.734 and Q2ext of 0.749, respectively.The result shows that favorable stability and good prediction capability of the model indicated that 3D-HoVAIF is applicable to the molecular structural characterization and biological activity prediction.
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Adsorption of Ethylene on Molecular Sieve by Frequency Response
GUI Xing-hua, LAI Jun-ling, LI Fei-fei, SUN Zhao-lin, SONG Li-juan1
2008, 21 (3): 38-42.
Abstract ( ) PDF ( 5627KB ) ( ) 　　
 
The various type and strength energy barrier was structured by the modified   molecular sieve. The adsorption and diffusivity performance of object adsorption molecular on the chose absorbent under the different temperature and pressure were determined. The results show that with the CuO mass fraction increase, the adsorptive capacity of ethylene in CuO/HMor first increases and then decreases. With the Cs+ mass fraction increase, total adsorptive capacity of ethylene in Cs+/HMor increases, high frequency adsorptive capacity increases, low frequency adsorptive capacity decreases. Compared adsorption capacity derived from the frequency response spectra with adsorption capacity derived from the intelligent gravimetric analyser, consequently adsorption mechanism which was explanded by frequency response method is reliability.
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Reaction Property Research of Magnetic Loaded Nano-Catalyst to Synthesized Benzyl Butyrate
QIAN Jian-hua, QIN Jin-lan, LIU Lin, XING Jin-juan, TIAN Jing-bo
2008, 21 (3): 43-45.
Abstract ( ) PDF ( 964KB ) ( ) 　　
 
Magnetic nano-Fe3O4 was prepared by hydrothermal method which was further to synthesis S2O2-8/Fe3O4, a magnetic nano-catalyst prepared by impregnation and ultrasonic method. Benzyl butyrate was catalytic synthesized with S2O2-8/Fe3O4, the influences of the loaded amount over the catalyst, activation temperature on the reaction were researched, and the recovery and reuse of the catalyst were discussed. The results indicate the esterification rate of the synthesized reaction by impregnation method is 85.6%, the purity of the product is 94.1%, while the selectivity of the catalyst obtained by ultrasonic method have an advantage over it obtained by impregnation method. 
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The Estimation and Validation of Liquid Density Based on Volume Translation Method
 
LIANG Ping, TIAN Yuan, TANG Ke
2008, 21 (3): 46-48.
Abstract ( ) PDF ( 974KB ) ( ) 　　
Using volume translation method to improve the calculation of the accuracy of liquid density for the SRK state equation ,so has no influence on the gas -liquid balance. On the basis of SRK state equation and volume translation method and PR state equation, more accurate calculation results of the density of saturated liquid were obtained. And the results were compared with the measured data of different methods.The results show that the calculation results of saturated liquid density using volume translation method are more accurate than using the SRK state equation or PR state equation and improved the scope of the application of SRK state equation.
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Experiment on Trachyte in Huangshatuo Oilfield
ZHANG Hong
2008, 21 (3): 49-52.
Abstract ( ) PDF ( 1946KB ) ( ) 　　
Experimental on fluidity of low permeability reservoir for Xiao 22-14-20 reservoirs of liaohe huangshatuo area was carried. The results show that water sensitivity is medium but slightly,critical salinity is bellow 2 500 mg/L,configuration of relative permeability curve basically presented that oil phase descended quickly,water phase rised rapidly and span of oil-water phase is small,which is the characterizes of fractured oil reservoir relative permeability curve.In the course of water development,it is necessary to ensure sufficiently standard quality and avoid pollutting and building up pay zone.The plan of water flood recovery to keep energy have been performed,the rate of recovery have been improved comparing natural recovery.
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ransesterification of Castor Oil to Biodiesel Using CaOas a Solid Base Catalyst
JIN Fu-quan， NIU Yu-lan， LI Bing， LI Xiao-hong
2008, 21 (3): 53-56.
Abstract ( ) PDF ( 2369KB ) ( ) 　　
The solid base catalyst CaO was prepared and characterized by XRD technique and low temperature nitrogen adsorption-desorption technique respectively. Transesterification of castor oil to biodiesel using CaO as a solid base catalyst was studied. The separate effects of reaction temperature, molar ratio of methanol to oil, catalyst dosage and reaction time on methyl ester yield were investigated.Under the optimal conditions of reaction temperature 65 ℃, molar ratio of alcohol to oil 9∶1, mass fraction of catalyst 1.5% and reaction time 2.5 h, the methyl ester average yield is 92%. The product was analyzed by gas chromatographic technique and mass fraction of methyl ester is 97.6%.The products after reaction is dealt with easily and the environment is not polluted and the catalyst can be activated and reused.
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Reaction Conditions of Slurry-Bed Hydrocracking to Liaohe Residue
ZHANG Shu-yi, LUO hui, DENG Wen-an, LIU Dong, QUE Guo-he
2008, 21 (3): 57-59.
Abstract ( ) PDF ( 1614KB ) ( ) 　　
 
The Liaohe inferior residue was studied as object and the slurry-bed hydrocracking reaction to Liaohe residue was simulated by the autoclave reaction. The effects of oil-soluble dispersed Ni catalyst on residue conversion under different reaction conditions were investigated. The results show that for the oil-soluble dispersed Ni catalyst, the use of the sulfide agent is superior to without sulfide agent; sulfur is the best sulfide agent. The best reaction conditions for hydrocracking Liaohe residue using oil-soluble dispersed Ni catalyst are: oil-soluble catalyst concentration 300 μg/g, the initial hydrogen pressure of 7.0 MPa, reaction temperature is standard temperature (t+5 )℃, reaction time of 1 h.
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Impact of Adding Surfactants on the Oil Recovery Factor by Steam Injection
ZHANG Yi-xiang
2008, 21 (3): 60-62.
Abstract ( ) PDF ( 1078KB ) ( ) 　　
By studying the steam injection mechanism of adding surfactants and analyzing the microscopic characteristics of emulsions, the differences between steam injections with surfactants and without surfactants (conventional) are summarized in two aspects: the difference in setting heating zone area and the difference in the internal energy of heated object, based on which the methods for calculating steam marching speed, heating area and thermal loss in the process of steam injection with surfactants added are systematically described. By way of theoretical analysis, the philosophy for steam injection result under the effect of surfactants being superior to conventional CSS is expounded. The optimum method for EOR as well as the philosophy and method for minimizing thermal loss is deduced.
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Effect of Buried Depth on Thermodynamic Properties of Hot Oil Pipeline in Steady Operation
LIN Ming-zhen， LI Chuan-xian， YANG Fei
2008, 21 (3): 63-67.
Abstract ( ) PDF ( 1833KB ) ( ) 　　
 
Based on impact of buried depth on thermodynamic properties of hot oil pipeline, the method that pipe sections with different buried depths were treated with different radius of heat influence. Heat differential equation of hot oil pipeline in steady operation was solved by means of finite element method, and calculation software was programmed to calculate the axial and transverse temperature field of pipeline. It was found that the result calculated by the software was more accurate. The effect of buried depth on the thermodynamic properties of pipeline in different seasons was also discussed in detail. The results indicate that if the calculated depth is larger than the actual value in winter, the calculated result of temperature field is larger than actual value, which is adverse for safety of pipeline operation. Otherwise, a smaller calculated buried depth would generate a smaller calculated result of temperature field, which would lead to costly pipeline operation. In summer, the situation is the opposite.
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View Factor Calculation for Pool Fire With Cross Wind
MENG Yi-fei, JIANG Jun-cheng, WANG Yan-fu
2008, 21 (3): 68-70.
Abstract ( ) PDF ( 2611KB ) ( ) 　　
On the base of basic theory of view factor, the view factor computation technology of pool fire with cross wind was studied. Related formulas for key parameters of view factor calculation were deduced according to the geometry topology, and further, the radiation surface of pool fire with cross wind was reasonably separated to establish the numerical computation formula of view factor. A procedure was developed using VB 6.0 for calculating view factor of pool fire with cross wind. From samples calculation, it was found that the procedure is reliable for pool fire without cross wind by comparing the result with what from theoretical model, and the new method can also effectively conquer the empirical model's shortcoming: incapable of calculating the view factor of pool fire with cross wind.
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The Analysis of Soft Tube Bursting for Feeding Liquefied Chlorine
 
ZHANG Li-jing， DING Li， YUAN Ming-lang
2008, 21 (3): 71-74.
Abstract ( ) PDF ( 2430KB ) ( ) 　　
A bursting accident of soft tube close to the entrance of the storage tank happens when the tank was filled and almost finished, which resulted in the leakage of liquefied chlorine and human chlorine gas poisoning. The maximal liquid hammer pressure caused by cutting off valve was calculated based on the theory of liquid hammer, and the strength of the tube was checked. The results show that the maximal liquid hammer pressure reaches to 2.6 MPa, which is almost 6.5 times as high as the normal working pressure. The fatigue phenomenon of soft tube would happen as repeated liquid hammer. It would induce the premature failure of the tube which may be the technical reasons for this accident. It is deduced that the maximal liquid hammer pressure of the pipes should be taken in consideration at designing stage, and relevant measures should be taken to reduce the destructive power in operating.
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Numerical Calculation Method on Current and Potential of Impressed Current Cathodic Protection System for Pipeline
CHEN Shi-yi, WU Xian-ce, JIANG Guo-ye
2008, 21 (3): 75-78.
Abstract ( ) PDF ( 1933KB ) ( ) 　　
A numerical method is presented to calculate the current and potential of impressed current cathodic protection system for the buried steel pipeline protected by two cathodic protection stations jointly. A resistance circuit with DC supplies is usd to simulate the system through the discretization scheme. Impressed potential and current along the pipeline are found out by mesh-current method. The numerical results have a good agreement with the analytic results and measured ones from Tianjin to Beijing aviation kerosene pipeline. The numerical results show that the coating damage causes increase in protective current and decrease in absolute value of potential along pipeline. The coating damage has less effect on the position where absolute value of potential is minimal, while the output voltage of DC supplies has more on the position. The nearer the location of coating damage is to a cathodic protection station, the bigger the difference of protective currents of the two stations is.
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Investigation of the Turbulent Flow Characteristic in a Stirred Mixer With Propeller
YU Yan-fang, MENG Hui-bo, Gong Bin, WU Jian-hua
2008, 21 (3): 79-82.
Abstract ( ) PDF ( 3631KB ) ( ) 　　
The turbulent flow characteristic in a stirred mixer with propeller was predicted based on multi-reference frame by using CFD turbulent model. Some detailed information about the velocity and turbulence kinetic energy was obtained. The simulated results show that the mean velocities increase firstly then decrease as radial position increasing, while the values of mean velocities close to the impeller are larger which were found in good agreement with the experimental results reported in the literature. Though the velocity distributions at different axial position above the stirrer are also much smoother, the values of velocity increase firstly then decrease in the discharged zone. The turbulence in the discharged zone tends to be nonuniform and the magnitude of the turbulent kinetic may have 7~9 times difference at the same axial or radial position. It is priority to select propeller for the axial speed field as main field, long distance transmission compared with traditional typical three-blade impeller of 45°.
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Numerical Simulation of Thermal-Hydraulic Characteristics Through  a Helical Coiled Tube With Constant Heat Flux for Laminar Flow
WU Shuang-ying, CHEN Su-jun, LI You-rong, LI Long-jian
2008, 21 (3): 83-87.
Abstract ( ) PDF ( 4562KB ) ( ) 　　
A numerical method for simulating the developments and distributions of heat transfer and flow fields was proposed. The effects of Reynolds number, curvature ratio, and coil pitch on the average friction factor, average Nusselt number at different axial cross-sections and the total entropy generation rate in a helical coiled tube with uniform heat flux was presented when Reynolds number is 200~1 000, dimensionless pitch 0.1~0.2 and dimensionless curvature ratio 0.1~0.3. The results show that the effect of the secondary flow is enhanced with the increase of turning angle, the maximum velocity perpendicular to axial cross section shifts toward the outer side of helical coiled tube and two Dean roll cells appear with the increase of axial turning angle. Furthermore, the average friction factor, average Nusselt number at different axial cross-sections and the total entropy generation rate present different characteristics when the Reynolds number, curvature ratio and pitch change. Compared with the curvature ratio, the pitch has relatively little influence on convective heat transfer performance and the total entropy generation. In the meantime, the entropy generation caused by viscous flow is much less than that caused by heat transfer and can be neglected.
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Identification for High Power Amplifiers With Memory
DING Yuan-ming, SHEN Qing-bo
2008, 21 (3): 88-91.
Abstract ( ) PDF ( 2131KB ) ( ) 　　
An adaptive identification method was proposed to estimate for the characteristics of high power amplifiers (HPA) with memory in orthogonal frequency division multiplexing (OFDM) communication systems. The complex Wiener-Hammerstein model (WHM) was adopted to describe the input-output relationship of unknown HPA and a power series model with memory (PSMWM) was used to approximate the HPA expressed by WHM in base-band. Furthermore，the orders of PSMWM were chosen by Akaikes information criterion (AIC), and the RLS algorithm was used to estimate parameters of HPA in on-line manner. Finally，the effectiveness and fast convergence of the proposed identification method are validated by numerical simulation example.
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Integration of Isomerism System Based on OPC Technology and Industrial Ethernet
REN Wen, LIANG Lan-zhen
2008, 21 (3): 92-96.
Abstract ( ) PDF ( 1940KB ) ( ) 　　
The industry ethernet and the OPC technology were introduced, and one kind of realizing isomerism system integration scheme based on the industry ethernet and OPC technology was proposed. The design method of the representative MODBUS/TCP OPC date access server based on Delphi7 and Huafu OPC Tool Kit were elaborated. The result indicates that the scheme causes the data transfer and share between the isomerism platform are possibly, and provides a effective feasible way for enterprises automated transformation and promotion.
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