In order to simulate the effect of leakage of natural gases with high contents of CO2 and N2 on the methane hydrates reservoir overlying, the replacement experiments of CH4 hydrates by using two groups of gas mixtures were observed with a selfdesigned device at 277.15 K, initial pressure 6.37 MPa and at 275.15 K, initial pressure 4.30 MPa respectively. The quartz sand and 3.5% NaCl aqueous solution were mixed to simulate seafloor and two groups of gas mixtures, one has high contents of N2 and another has high contents of CO2, were chosen from northern South China Sea. Experimental data show that the variation of CO2 is the most and the variation of N2 is much less. It indicate that CO2 plays a leading role. The replacement efficiency of two groups of gas mixtures at different experimental conditions are 8.64% and 20.71% at 140 h of experiment. Based on the experimental results, a simple replacement mechanism of CH4 hydrate dissociated with CO2 in porous medium system was proposed.
SnSb intermetallic was synthesized in aqueous solution and organic solvent using SnCl2•H2O, SbCl3 as metal precursors, NaBH4, Zn as reducing agent, respectively. The XRD, SEM, EDS, particle analyzer and BET were used to characterize the phase, morphology, particle size and pore structure of SnSb intermetallic. The power desulphurization experiment for crude water/oil emulsion was performed using the SnSb intermetallic as functional material. The results show that the morphology of SnSb intermetallic synthesized in aqueous with NaBH4 as reducing agent is "bricklike" structure, while for the SnSb intermetallic synthesized in organic solvent with Zn as reducing agent, the morphology is "leaflike" structure. The desulphurization rate of crude oil is enhanced with the increase of particle morphology defect and applied voltage, and the decrease of the average particle diameter. The desulphurization rate of crude oil by SnSb intermetallic synthesized with Zn in glycerol can reach 28.2%.
Heavy oils of Venezuela heavy oil was separated into four fractions which were saturate, aromatic, resin and nC7 insoluble asphaltene. Average structural parameters of heavy oil and its fractions were analyzed and computed. The results show that the same trend of average molecular weight, CT，HT，fA，CA，RA，RT，RN，CN , C.I. has the size order which is asphaltene，resin，aromatic，saturate. The infrared spectrum of Venezuela heavy oil' saturate shows that there were two strong absorption peaks between 2 800~3 100 cm-1 and 1 350~1 390 cm-1 ,which were methyl and methylene. Groups of hydroxyl and carbonyl lead to hydrogen bond between resin and asphaltene.
The relationship between density and low temperature cracking with the densitytemperature relationship and coefficient of thermal expansion of aggregate,relationship between density and temperature,creep property and temperature,creep property and density was studied. The results show that the density, the Logarithm of the creep stiffness and m value are linear to temperature. The Logarithm of the creep stiffness and m value are all linear to density. The density is closely related with lowtemperature cracking performance.The relationship between density and temperature can be used to evaluate the performance in low temperature condition and the judgment of performance in low temperature is consistent with that from creep property of asphalt.
The effect of hydrothermal synthesis conditions on both relative crystallinity and phase purity of ZSM22 zeolites was investigated in SiO2Al2O3K2ODAHH2O system, hereby DAH referring to 1,6diaminohexane as template. The resulting samples were characterized by powder Xray diffraction (XRD) and inductively coupled plasma (ICP) analyses in order to examine the structure, XRD phase, and chemical composition. As a result, several ZSM22 zeolites with the higher phase purity were synthesized at respective temperatures from 433 K up to 438 K by use of the different gels which involved SiO2/Al2O3 molar ratios of 80~100 and OH-/SiO2 molar ratios of 0.33~0.35. It is found that the relative crystallinity and phase purity of ZSM22 zeolites markedly varied as a function of crystallization temperature, SiO2/Al2O3 and OH-/SiO2 molar ratios. In fact, an adequate increase in crystallization temperature improves on ZSM22 phase purity, followed a significant enhancement of relative crystallinity. Although the ZSM5 crystal growth takes place predominantly in the solid phase, the decrease in the range of SiO2/Al2O3 ratio less than 80 leads to a gradual increase in the ZSM5 phase fraction while the increase in SiO2/Al2O3 ratio larger than 110 also enhances the phase fraction of cristobalite. Furthermore, Si/Al atomic ratios in ZSM22 framework located the range of 41.8~53.4, and by correlating the Si/Al ratio of ZSM22 framework with the SiO2/Al2O3 ratio of aluminosilicate gels, it is noted that the nominal ratios in ZSM22 framework tended to shift towards the center of the Si/Al ratio interval mentioned above.
The immobilized 1amyl3methylimidazolium hydrosulfate ionic liquid was obtained by physical impregnation on molecular sieve. The oxidationextraction desulfurization effect of FCC gasoline using supported ionic liquid (SIL) were investigated. The results show that, the pore size of molecular sieve have certain impact on the desulfurization effect. With NaY molecular sieve as loading material, hydrogen peroxide (35%) as the oxidant，the desulfurization condition were optimized by varying oxidant dosage, extraction time, the ratio of ILs/oil, and so on. The best desulfurization rate was obtained after 60 min under the condition of 10 g SIL and 100 mL oil and 1 mL H2O2, at 40 ℃ with the sufur removal of 94% for FCC gasoline. The sulfur content of FCC gasoline has decreased to 10 μg/g below. After the reaction, the fuel oil and supported ionic liquid can be separated simply by decantation, the supported ionic liquid can be recycled .
Cpper phosphotungstate was synthesize by phosphotungstic acid and nitric acid copper as raw materials. Oxidative desulfurization reaction of model oil was studied by copper phosphotungstate as catalyst and H2O2 as oxidant. The experiment indicate various oxidative desulfurization system, reaction temperature, catalytic amount, amount of hydrogen peroxide and reaction time influenced on oxidative desulfurization effect. The results show that a combined copper phosphotungstate, CTAB and H2O2 could lead to a good conversion of DBT. Reaction temperature was 40 ℃,catalytic amount was 0.01 g, volume of hydrogen peroxide was 0.5 mL, reaction time was 1 h, which made conversion rate of dibenzothiophene up to 93%. The catalyst may was recycled five times and desulfurization effecience of mode oil isn't decreased.
The hindered phenolic antioxidant was synthesized with 3(3,5ditertbutyl4hydroxyphenyl) propionic acid and nbutyl alcohol as raw materials by esterifying reaction. The antioxidant characterized by infrared spectroscopy and HNMR was 3(3,5ditertbutyl4hydroxyphenyl) nbutyl propionate. The optimal synthesis conditions were as follows: reflux time 8 h, the molar ratio of 3(3,5ditertbutyl4hydroxyphenyl) propionic acid to nbutyl alcohol 1∶2 and the catalyst amount 3.2% on the total reacts. The effects of hindered phenolic antioxidant on the protective effect of NR vulcanizates were studied by mechanical property testing, infrared spectroscopy, thermal analysis. These results indicate that the hindered phenolic antioxidant havepronounced antiaging properties, which is higher than those of BHT antioxidant. Besides, the synthesized hindered phenolic antioxidant had no color pollution for rubber.
At present, the operating inlet oil temperature to the pump station along Asai pipeline is much higher than the gel point of the crude oil. And the pigging frequency is much higher. There is much waxes removed from the pipeline during the pigging operation. It not only blocks the inlets of heating furnace, but also consumes more thermal energies. In this paper, the wax deposition profiles of the crude oil along Asai pipeline at different inlet temperatures under normal conditions were predicted by using the unified wax deposition model, and also the wax deposition distribution under the condition from damaging thermal insulation was also examined. The prediction results show that the wax deposit mainly accumulated in the inlets of the pump stations. On this basis, a new pigging program involving pigging frequency was proposed, and the same time the inlet oil temperature was also optimized to be a lower value. In winter, the inlet oil temperature is advised to be 40 ℃.While in other seasons, the temperature is 35 ℃. The prediction results were compared with the field data, the relative average error is 9.49%.
Permeability drop down gradually with the decrease of reservoir pressure in the process of developing of pressure sensitive reservoir. The oil well production and development effectiveness were affected. In order to quantify the influence of variety of formation pressure. Starting from the experimental data, the relationship between permeability and reservoir pressure was obtained. The restored regularity of permeability and oil well production in process of varying of reservoir pressure were researched on combining the oilfield development practice. The effectiveness of advanced water injection in process of development of pressure sensitive reservoir were studied.
Interaction between three surfactants and hydrophobically associating watersoluble polymers (HAWP) were studied. The experimental results show that the interactions differ according to the types of surfactants. Viscosity increases and interfacial activity decreases for the interaction of alkanolamide or petroleum sulfonate and HAWP, while viscosity decreases and interfacial activity remains consistent for the interaction of betaine and HAWP. With the increase of substituent carbon numbers, interactive force decreases between sulfonates and HAWP, and increases between betaines and HAWP. The force sequence of interaction between surfactants and HAWP is alkanolamide,sulfonate,betaine under the same low substituent carbon numbers.
The interfacial tensions (IFTs) between zwitterionic surfactant, hexadecyl diethyl2hydroxy1proply sulfobetaine and Shengli crude oil were investigated using spinning drop method. The influences of salinity, concentration of divalent ions and weak base NaHCO3 on IFT were discussed. The experimental results show the mixed adsorption of betaine molecules and the active components present in the crude oil at the interface and the synergism of them together determine the IFT of oilwater. The betaine surfactant with electroneutrality permits closer packing at the interface. An increase in the concentration of Na+ and Mg2+ with less ion radii appears to decrease the IFT gradually, however, the value of IFT remain at higher level with increase in the concentration of Ca2+ with larger ion radius. NaHCO3 can react with the active components present in the crude oil, which reduces IFT to ultralow value. In this case, one can find that total salinity is the key factor that determines the IFT, while ionic type has little effect on the IFT.
The wetting properties of quartz surface modified by adsorption films of fluorosurfactants were investigated using the sessile drop analysis. The influences of temperature and different electrolytes were expounded and laboratory simulation of displacement testing was carried out. The results show that zwitterionic fluorosurfactant FO1 will effectively alter the wettability of quartz surface. FO1 can both modify the quartz surface from hydrophilic surface to neutral one in distilled water and formation water. Meanwhile, FO1 shows better heat resistance and salt tolerance. The result of laboratory simulation of displacement experiment show that the core surface is controlled in slightly waterwetting by zwitterionic fluorosurfactan solutions, which is beneficial to the removing of the water film from core surface and reducing the percolation resistance of water flooding, and results in decrease of water injection pressure and enhancement of the oil recovery.
The two surfactants (SS, SHSAHN6) and two polymers (KYPAM, ZLⅡ) compound with Na2CO3 was made, then study on the viscoelasticity of multisystem, evaluate the interfacial tension of multisystem and do physical oil displacement experiments with heterogeneous artificial cores. The optimal multisystem was then selected among various systems as the one to be applied in the field test. The results show that: Along with the increase of shear rate, the viscosity of each multisystem decreases, but the decline phase is not obvious. The elasticity of different systems increases along with the increase of shear rate and the superposition of elasticity points indicate they have good match. Four systems are all achieve ultralow interfacial tension in five minutes, and the steady interfacial tension will remain low. SS is better than SHSAHN6 in decreasing interfacial tension, and the surface tension stability of KYPAM ternary system is much better than ZLⅡternary system. From the perspective of flooding effect evaluation, the chemical flooding recovery of KYPAM ternary system is higher than ZLⅡternary system, the oil displacement efficiency of SS ternary system is better than SHSAHN6 ternary system.
In Zhuangxi Oil Production Station crude stabilization tank as an example, studied the influences of the composition of the oil tank bottom water on oil tank bottom corrosion. Further studies on the mechanism of electrochemical corrosion with the method of polarization curves. Focus on the tank bottom water and various ion on the corrosion rate trend from electrochemical corrosion aspects and effect of ion coordonation. The results show that the stability of Cl-, Ca2+ content in Zhuangxi crude oil station is higher than other oil quality ,and the water quality can accelerated the corrosion rate of oil tank in a way.
When a rigid, flatended uniform indenter was pressed on the surface of a layered substrate, a singular stress field and Kdominant region should arise adjacent to the indentation edges. The indentation stress intensity factor is also a fracture parameter similar to the mode I crack, which represents the intensification of the stress fields. In present article, a method to formulize the ISIF for the singular stress fields induced by indentation is proposed based on the conservation integral.
Simulating the operating situation of feeding distributor used in vacuum distillation tower with the media of air and water, a new type crossshaped baffler feeding distributor was tested to value its performance such as gas distribution uniformity, entrainment rate and process pressure. The results imitated structural parameters of the crossshaped baffler distributor by CFX fluid mechanics modeling software were validated. Its structural parameters were confirmed. It is tested that the crossshaped baffler feeding distributor is excellent in various performance，especially in simple structure, small space and reasonable design.
