In order to improve the safety of air flooding and quality of heavy oil, static oxidation experiments were conducted to research the effect of oil displacement agent on the catalytic low temperature oxidation (CLTO) of heavy oil. The results showed that the oil displacement agent could accelerate the oxygen consumption rate, and especially the effect of NaOH and PAM on oxygen consumption rate were obvious. Saturates, aromatics, resins and asphaltenes (SARA) analysis and experiments using oil displacement agent were preformed to study the effect of oil displacement agent on the crude oil components. Saturates and aromatics were converted to resins and asphaltenes during low temperature oxidation (LTO), and the addition of Fe3O4 nanoparticles could reverse this change. This study can provide guidelines to select of oil displacement agent, improve the safety and increase the application of air flooding technology.
The nanometer autonomous vehicle assembly MoNiP hydrogenation catalysts were prepared by homogeneous precipitation using thiourea as precipitant matrix and citric acid as complexing agen. The catalysts were characterized by BET, NH3TPD, FTIR spectra of CO adsorbed and XPS. The results of BET and FTIR spectra of CO showed that when the content of thiourea was 40%, catalytic performance of the catalyst was best. The homogeneous precipitation catalyst achieved the desulfurization rate of 95.3% which was higher than the reference catalyst by 1.7%.
Polyvinyl chloride (PVC) is generally used for phthalate plasticizers, because of its high plasticizing efficiency. These phthalate plasticizers will cause the problems of durability, toxicity and potential carcinogenicity, they can make service life shorter, endanger human and animal health. So it has been gradually replaced by the new type of plasticizer. Polyester plasticizer is a kind of green environmental protection plasticizer and can better solve the disadvantage of traditional plasticizer, so it was widely studied at home and abroad. In this article, plasticizing mechanism(Lubricity theory, Gel theory, Free volume theory), selection criteria, synthesis and classification of the polyester plasticizer are introduced. The polyester plasticizer is mainly divided into two categories:biological polyester plasticizer and petroleum polyester plasticizer.
In order to deal with the problems, such as reservoir pressure decreasing rapidly, degassing serious, production decline fast and other issues, in the waterflooding process in Xing 71 test area, the indoor experimental research of the advanced water injection in Xing 71 test area was carried out, and the three parallel cores were applied to get the reasonable technical parameters in the indoor experiment and decide the reasonable technical parameters of the advanced water injection in Xing 71 test area. The results of the experiment showed that, for Xing 71 test area, when the pressure level in core porosity was 120% and the advanced water injection rate was 0.014 mL/min, the indoor experiments could achieve a better development result. Based on the experimental results, the dimensionless mathematical model was established and similarity criterion was used to get the advanced water injection reasonable technical parameters in the field. The results were applied to field practice in Xing 71 test area and the production practice had achieved good development results.
The superheated steam has been applied in the industrial application, and the demand for the study on the production capacity is increased. Based on the studies of radius calculation, the hot zone and cold zone have been calculated separately. The cold oil flows from the supply boundary to the hot zone, and then flows through the hot zone to wellbore. The quasi steady state solution has been used to solve the problem. Using the model to calculate oil productivity for two cycles in KMK oil field, the relative error of cumulative water production is less than 0.5%.
In recent years, with the growth of oil consumption and the reduce of new proved reserves, the development of high viscosity oil reservoir was paid more and more attention. As Kongnan block of Dagang oilfield has characteristics of hypercoagulability, high viscosity and high salinity, core flow experimental apparatus and core displacement experiment apparatus were used to study the effect of oil displacement efficiency of polymer/surfactant combination system, and analyze the mechanism of the relationship between recovery growth and core permeability. The results showed that, for the weak heterogeneous reservoir, with the increase of core permeability, the resistance coefficient and residual resistance coefficient of the polymer/surfactant combination system were decreased. With the increase of viscosity ratio (μsp/μo) and core permeability, the oil recovery increased, but the increase rate decreased. With the increasing of the core permeability, the size of the rock increased, while the inaccessible pore volume decreased. So the adaptability of the reservoir and the polymer/surfactant combination system was affected by the average permeability, and then the effect of the polymer flooding of the polymer/surfactant combination system flooding was influenced. Comprehensively considering technical and economic effects，the reasonable viscosity ratio (μsp/μo) in polymer flooding should be about 0.5~1.0．
Firstly, the molecular coil size of 4 kinds of polymers, whose molecular weight polymers is 8 million, 12 million, 16 million and 20 million respectively, was measured by the light blockage counter. Then pore cumulative distribution curve of field cores was measured by kerosene mass method. Finally the relationship curves between polymer molecular coil size and inaccessible pore volume of field cores were plotted. On the basis of this study, the water saturation value is assigned to the volume of the pore volume, and the polymer molecular weight with better compatibility with rock pores is optimized according to the relationship curve drawn. This method is based on the micro channel of underground rock. It has reasonable value and simple steps. And there are some guidances for the selection of the polymer in the oil field.
The MA18 block of Xinjiang oil field belongs to lowpermeability reservoir, whose pressure sensibility is medium to strong. Fracture is adopted to develop this block. The effect of fracture was simulated by diamondshaped inversed 9 point pattern using Eclipse. The threshold pressure gradient and the voltagesensitive effect were taken into consideration in this pattern. Considering the position diversity of edge well，corner well and central well in the field of seepage flow， the different length of fracture was simulated In this way, the optimum parameters of the fracture were obtained. Finally, the regression relation of the fracturing effect and the fracture parameters acquired by the simulation of FracproPT were got which could guide the construction of optimal project efficiently.
For the sake of environment protection, shallow formation waters were studied for the preparation of guar gum fracturing fluids in gas fields, west Sichuan. The fracturing fluid prepared with formation water had viscosity of 100 mPa·s after shearing 60 min(170 s-1) at 45 ℃, rate of permeability impairment of only 23.86%, surface tension of 27.82 mN/m, rate of swelling reduction of 87.5%, residue content of 518 mg/L. The formation water fracturing fluids were successfully used in SF382 and SF384, which respectively improved natural gas production of 1.14×104 m3/d and 1.68 ×104 m3/d. This technology enabled the reuse of formation sewage water in gas fields.
In order to provide a basis for decisionmaking on improving the effect of ASP flooding with strong base, this paper carried out the research on the relationship of produced liquid reagent concentration and its viscosity to interfacial tension, through taking Lamadian oilfield produced fluid of ampling wells as research object. And this paper also explored the effect of ASP system slug viscosity to produced liquid reagent concentration and chromatographic separation degree. The results showed that with the increasing of the sampling wells permeability in reservoir, the produced liquid concentration of alkali, surface active agent and polymer present "first rising and then falling" change trend. With the concentration increasing of polymer in produced liquid, its viscosity and interfacial tension gradually increased. With the concentration increasing of alkali and surface active agent in produced liquid, its viscosity and interfacial tension gradually reduced. By analysis of the produced liquid concentration, there is a more serious phenomenon of chromatographic separation during the process of ASP flooding with strong base. Throngh enhancing the viscosity of ASP system, it can weak the separation of chromatographic separation, which can improve the oil encreasement effect of ASP flooding.
In order to evaluate the adaptability of nanometer microspheres to the Pubei Test Block, laboratory experiment study based on the nanometer microspheres profile controlling and flooding mechanism was carried out. The experimental results showed that nanometer microspheres dissolved in oilfield sewage owned a good dispersion, and its median grain diameter can meet the plugging requirement. When the solution concentration was 2 000 mg/L, nanometer microspheres hydration swelling effect was the best, and its multiple expand reached 5.7 after thirty days. The final oil recovery was raised by 10% by nanometer microspheres profile control and displacement. It was concluded that nanometer microspheres could plug the high permeability layer of nonhomogeneous formation. The experimental results can provide theoretical bases and technological support for enhance oil recovery of low permeability reservoir．
Influence of ASP system on the fracture conductivity of alkaliresistance resin sands and quartz sands was studied. The results showed that compared with the weak base, the dissolution of strong base on the quartz sands was more serious. And the damage percentage of the particles was higher. Therefore the reduction of conductivity of fractures packed with sands was larger. Compared with quartz sands, there was little difference between the dissolution of weak base on the alkaliresistance resin sands and that of weak base on the alkaliresistance resin sands. So it was the same to conductivity. With the increase of closing pressure, the conductivity of quartz sands and alkaliresistance resin sands were both weakened. But the reduction degree became gradually small. Compared with quartz sands, the influence of closing pressure on the conductivity of fractures packed with alkaliresistance resin sands was weak. And the fracture conductivity capacity was stronger.
There are many problems in the development process of the low permeability oilfields including water injection difficulty, high water flooded degree, low utilization efficiency of injected water and gas channeling of gas injection. Through a large number of laboratory physical simulation experiments and tests, the best CO2foam system was selected out for a low permeability blocks CO2foam flooding in Jilin oil field. The stability, foaminess, injectivity and applicable scope of the permeability of three systems were conducted. The results showed that the three kinds of foam agent all had good foaminess and stability, and all of them could be injected within the range. When the temperature rose from 45 ℃ to 100 ℃, the halflife of foam systems sharply reduced, and the stability of them turned bad. In the three foam systems, FP388 was the optimal one which had best foaminess and comprehensive performance.
In order to study the typical block of onshore oil fields, a twodimensional interlayer physical model is designed. The experiment scheme of hydrophobic associating polymer flooding after polymer flooding is monitored by self developed saturation monitoring system. The spread and use of typical onshore oil field blocks are grasped by carrying out the experiment about the displacement, the use and the monitor of the twodimensional interlayer physical model and monitoring and the oil saturation distribution in the chemical flooding stage in real time. The results indicated that: in twodimensional interlayer core parallel experiments, recovery efficiency of the land typical block could be improved by 13.69% through injecting 1.05 PV Huading I hydrophobic associating polymer after polymer flooding. Saturation monitoring data showed that chemical flooding stage after polymer flooding had formed oil wall inordinately, increased filtrational resistance, so as to enlarge the swept volume and improve recovery efficiency. The key to improve the oil recovery in polymer flooding was the efficient use of the low permeability layer. A wide low oil saturation line was formed in core mainstream channels with a strong oil displacement efficiency after Huading I hydrophobic associating polymer flooding.
As an important tertiary recovery technology, polymer flooding has obtained certain development achievement in Sanan development area of Daqing oilfield. But the surplus sewage exhausted from the polymer flooding has caused the waste of resource and the environmental pollution. The core flooding experiment which has diluted the polymer solution with the fresh water and the sewage was made to get this problem solved. According to the experimental results, the relationship between the concentration and viscosity of different molecular weight polymer was analyzed. Also, the injection capacity of the polymer solution with different molecular weight, permeability and concentration was analyzed. The injection capacity limit of the reservoir was divided according to the actual application. It has provided the reference for the screening of molecular weight and concentration of the polymer in actual production.
The sedimentary process of Wutonggou formation is controlled by coastal underwater alluvial fan and alluvial fan in the Tainan depression of Tuha basin. For the complicated sedimentary setting, it's difficult to identificate the microfacises with lacking of systematic studies on log facies. The representative sedimentation microfacies with obvious facies marker were selected to make contrast and summarize up the features of well loggs. The model was established for different microfacies. The first 11 lowfrequence wavelet coefficients can perform well in reconstructing variation trend of GR log. There are significant differences in the wavelet coefficients and reconstructed lowfrequence curves and highfrequence curves among different sedimentation microfacies. The variation law of lowfrequence wavelet coefficients in every microfacies was analysized from the hydrodynamic force and other sedimentology aspects. By doing these, the abstract information of sedimentation microfacies belonging to geological space was converted into specific low dimensional feature vector of digital space. Based on this point and combing the characteristic of lowfrequence curves and highfrequence curves, a set of sedimentation microfacies identification templates was established. Sedimentation microfacies were identified by calculating the minimum Euclidean distance of logging curves between small layer and identification templates, with the combination of comparing the characteristic of lowfrequence curves and highfrequence curves between them.
Source rocks evaluation is of great importance for gas exploration in Changling depression of southern Songliao basin. Aimed to make clear the TOC distribution of source rocks in Shahezi formation, based on the logging data and core tested data, variable coefficient ΔlgR model was used to calculate the TOC quantitatively, source rocks of different TOC grade and their thickness distribution were described. The key coefficients in the model were calculated using variable coefficient ΔlgR model according to the sampled data of the studied area, and TOC calculation results can reflect the TOC underground accurately. TOC predicting error by variable coefficient ΔlgR model was about 19.1%, which was reduced 17.5% compared to traditional ΔlgR model. Source rocks in Changling depression are characterized by high TOC value, middle less source rocks, good source rocks and excellent source rocks account for 26.1%, 18.2% and 55.7% of all the source rocks in volume, respectively. Good and excellent source rocks mainly distributed in Heidimiao sag, the maximum thickness is over 400 meters, Haerjin and Qianbei sags also developed good source rocks the general thickness is 200~300 meters.
Pipe jacking project is regarded as a technology of nonexcavation pipe jacking construction project, which has the most prominent feature of adaptability. The cutter head is one of the key components of the jacking machine crossing oilgas pipelines, which major function is to accomplish crushing and peeling of rock soil of tunnel face, and takes a key role in digging function. Because of the difficulty of changing cutters and the complexity of the work environment, there is a high demand for the intensity of the cutter head. A corresponding cutter design program is established based on the special geology of the construction domain, and the torque and thrust calculation methods are given. Besides, the finite element model is established under the help of the ANSYS(finite element analysis software), so that the stress, strain, and strength reserve distribution are obtained. The analysis results show that the greatest equivalent stress appears at the interface between corbel and transmission shaft. The greatest stress is 37.6 MPa and the largest distortion is 0.06 mm.The result of this research provides effective theory evidence for optimal structural design of the cutter head.
The mathematical model of cathodic protection potential distribution with impressed current on the exterior of metal storage tank bottom is established and calculated by using Comsol multiphysics software. The effects of the numbers and layout of cathodic confluence points depth of auxiliary anode, soil resistivity, and the influence of polarization characteristic on protection potential distribution of tank bottom were studied. The results showed that, with other conditions unchanged, the way of setting confluence points on the center of tank bottom and more points confluence would produce better results of cathodic protection. But due to potential drop of tank bottom with little difference, and considering economic feasibility factors. Singlepoint confluence at the edges was proposed. Moreover, the smaller the soil resistivity was, the deeper the depth of auxiliary anode was. The tank bottom is not easy to be corroded and polarized. It is better for cathodic protection effect of tank bottom.
