Huabei Oilfield Research Articles

Construction of Cloud Storage Platform based on the MongoDB and its Application in the Oilfield Production

With the rapid development of the digital constructions in Huabei oilfield, the area that the automatic monitoring systems must cover becomes larger and larger over times. In addition, the systems built in different local region face many problems, such as the un-unified data format, decentral storage, difficult to share, and low data utilization. Based on MongoDB, a cloud storage platform is built, aiming at synchronizing all the real-time production data from the different automatic monitoring systems to the unified storage format. Then, the secondary development of unified production data on this platform can easily realize the oil/water well on-line analysis, 3D-simulation, real-time monitoring, report, etc. The built cloud platform will satisfy the demand of the integration and optimization for production engineering.

A Storage Platform of Petroleum Production based on MongoDB

The storage method of production data is the important factor of the informatization oilfield. Many aspects are impact on efficiency, such as data query, large-scale data analysis, data mining, real-time data compute. The most smart oilfield constructions of the Huabei Oilfield are based on SCADA or DCS system in PetroChina. There are some problems on data storage and usage by this approach, such as inconsistent data format, lacks of storage flexibility and extensibility, low data security and using rate, etc. The traditional ways are not suitable for large-scale production data storage, application and big data analysis. In this paper, a petroleum production storage platform based on MongoDB and relational database is designed. The platform is built for convert, transmission, save uniform data from mostly SCADA or DCS system, and can provide unified restful API for third-party data access. The Production Command System (PCS) is developed, which can provide functions of real-time monitoring, auto-computing different kinds of report, production data management, production schedule management, etc.

The Research and Application of Microbial Degradation Technology on Heavy Oil Reservoir in Huabei Oilfield

Mengulin sandstone reservoir in Huabei oilfield is low- temperature heavy oil reservoir. Recently, it is at later stage of waterflooding development. The producing degree of water flooding is poor, and it is difficult to keep yield stable. To improve oilfield development effect, according to the characteristics of reservoir geology, microbial enhanced oil recovery to improve oil displacement efficiency is researched. 2 microbial strains suitable for the reservoir conditions were screened indoor. The growth characteristics of strains, compatibility and function mechanism with crude oil were studied. Results show that the screened strains have very strong ability to utilize petroleum hydrocarbon to grow and metabolize, can achieve the purpose of reducing oil viscosity, and can also produce biological molecules with high surface activity to reduce the oil-water interfacial tension. 9 oil wells had been chosen to carry on the pilot test of microbial stimulation, of which 7 wells became effective with better experiment results. The measures effective rate is 77.8%, the increased oil is 1,093.5 tons and the valid is up to 190 days.

A case study of an ORC geothermal power demonstration system under partial load conditions in Huabei Oilfield, China

Liubei reservoir of Huabei oilfield, a typical mature oil and gas field in China, now has a water cut of 98% and the traditional “oil” field has become a “water” field. To further exploit the oilfield, a 500kW organic Rankine cycle using R245fa as the working fluid was designed and set up to use the coproduced fluid. Experiments under partial load conditions indicate that it is a good choice to use a plate heat exchanger as the preheater to be responsible for part load of the evaporator. In addition, dynamic test results show that the fluctuating of the geothermal water strongly affects the stability of the system’s performances, so attention should be paid on the stability of the geothermal water flow rate. Compared with the design generating capacity, the system did not get as much electricity as expected. Besides, exergy comparison analysis between design and partial load condition reveals that the intermediate heat exchanger (IHE) used to transfer heat from geothermal water to hot water becomes the main obstacle in view of exergy utilization ratio. Therefore, methods should be adopted to decrease the heat transfer temperature difference between the geothermal water and hot water, to reduce the exergy loss of the system.

Performance Evaluation and Adaptability Research of Flowing Gel System Prepared with Re-injected Waste Water

The crosslinking intensity and stability of flowing gel system prepared with re-injected waste water are seriously affected as the high salinity waste water contains a high concentration of Na+, Fe2+, S2−, Ca2+, etc. The influence of various ions on the flowing gel system can be reduced by increasing polymer concentration, adding new ferric ion stabilizing agent (MQ) and calcium ion eliminating agent (CW). The technique of profile controlling and oil-displacing is carried out in Chanan multi-purpose station, Chabei multi-purpose station and Chayi multi-purpose station of Huabei Oilfield. The flowing gel system is injected from 10 downflow wells and the 15 offsetting production wells have increased the yield by 1770 tons.

Research and Application on High Temperature Clean Fracturing Fluid System

Clean fracturing fluid is suitable for the transformation of low permeability reservoirs, with a strong waterproof Mintel, but temperature resistance is poor. As water base guanidine gum fracturing fluid doesn’t have effective function on Tong47 fault Block For Huabei Oilfield with characteristics of medium porosity, low permeability and strong water sensitivity, we proposed a new high temperature clean fracturing fluid system (120℃) which was prepared with anionic Gemini surfactant and other additives. The system was successfully applied in 7 wells, the average oil production increased 10.4 t/d, and the oil incremental effect is obvious.

Deinococcus petrolearius sp. nov. isolated from crude oil recovery water in China.

A Gram-stain positive, non-motile, spherical, red-pigmented and facultatively anaerobic bacterium, designated strain 6.1T, was isolated from a crude oil recovery water sample from the Huabei oil field in China. The novel strain exhibited tolerance of UV irradiation (>1000Jm-2). Based on 16S rRNA gene sequence comparisons, strain 6.1T shows high similarity to Deinococcus citri DSM 24791T (98.1%) and Deinococcus gobiensis I-0T (97.8%), with less than 93.5% similarity to other closely related taxa. The major cellular fatty acids were identified as summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH), followed by iso-C17:1 ω9c and C16:0. The polar lipid profile was found to contain phospholipids, glycolipids, phosphoglycolipids and aminophospholipids. The predominant respiratory quinone was identified as MK-8. The DNA G+C content was determined to be 68.3mol %. DNA-DNA hybridization between strain 6.1T and D. citri DSM 24791T was 45.6±7.1% and with D. gobiensis I-OT was 36.6±4.7%. On the basis of phylogenetic, chemotaxonomic and phenotypic data, we conclude strain 6.1T represents a novel species of the genus Deinococcus, for which we propose the name Deinococcus petrolearius sp. nov. The type strain is 6.1T (=CGMCC 1.15053T=KCTC 33744T).

Construction and preliminary test of a geothermal ORC system using geothermal resource from abandoned oil wells in the Huabei oilfield of China

In this study, a low-temperature geothermal organic Rankine cycle (ORC) system was designed to generate electric power using geothermal resource from abandoned oil wells in the Huabei oilfield of China. Several main sections were constructed including the geothermal water cycle, intermediate water cycle, ORC, cooling water cycle, lubricant oil cycle, bypass and control systems. Using R245fa as the working fluid, a four-stage axial turbine was specially designed and manufactured, to drive a grid-connected alternator. An onsite preliminary test was conducted in the oilfield and part of the experimental data were presented and analyzed. The turbine isentropic efficiency and ORC efficiency were evaluated. Besides, an intermediate cycle efficiency was proposed to show the influence of the heat loss of the intermediate water cycle on the system performance. Experimental results showed that a turbine efficiency of 78.52% and an ORC efficiency of 5.33% could be obtained. The average of intermediate cycle efficiency was 77.98%, indicating that the heat loss of the intermediate water cycle was considerable and should not be ignored. The construction and preliminary test of this ORC system could provide some meaningful references for the researchers and engineers to establish desirable geothermal ORC power plants using abandoned oil wells.

Corrosion behaviors of polysiloxane-ferroferric oxide coating coated on carbon steel in NaCl solution and geothermal water

Corrosion from plants and pipelines made of carbon steel is a severe problem for the utilization of geothermal energy. In order to control corrosion, various polysiloxane-ferroferric oxide composite coatings were successfully fabricated on carbon steel substrates. The morphologies and chemical compositions of these composite coatings were characterized. The thermal stability was tested by thermal gravity analysis (TGA). Wettability was investigated by contact angle measurement. Equivalent thickness was measured by weight method. The corrosion behaviors of composite coatings were tested by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in 3.5wt.% NaCl solution and simulated geothermal water of Huabei oilfield. According to potentiodynamic polarization curve and EIS, the inhibition of corrosion for each carbon steel coated with composite coating is improved, because the corrosion current density decreases by one or two orders of magnitude. Corrosion mechanism for carbon steel coated with composite coating was analyzed with EIS measurement and equivalent circuit simulation. TGA of various polysiloxane coatings shows less than 8% weight losses for all polysiloxane coatings tested at 300°C. The composite polysiloxane coatings show good corrosion resistance and thermal stability.

A new model for predicting the viscosity of heavy oil

ABSTRACTModels of heavy oil viscosity are considered as a function of temperature and API gravity in literature at home and abroad, and the API gravity is measured under the condition of 20°C, but without considering the effect of temperature on the API and colloid asphalt content in heavy oil. A total of 197 data points from 41 samples of Huabei oilfield are tested from previous studiesand five other heavy oil viscosity models, and the calculation value is much less than the measured value. The new prediction model of heavy oil viscosity is established by Simplex Method and the General Global Optimization Method. The new model takes into account the temperature, API, colloid asphalt, and the influence of temperature on API. Using the new model to predict the viscosity of heavy oil samples of Huabei oilfield, the average relative error of 3.36%, mean absolute error of 7.61%. The new prediction model is precise than other eight models, calculated values and measured values coincide when degree is higher.

The Effect of Emulsifying Capacity of ASP Flooding on Oil Displacement Efficiency for Jing-11 Fault Block Reservoir in Huabei Oil Field

The Effect of Emulsifying Capacity of ASP Flooding on Oil Displacement Efficiency for Jing-11 Fault Block Reservoir in Huabei Oil Field

Long-term oil contamination causes similar changes in microbial communities of two distinct soils.

Since total petroleum hydrocarbons (TPH) are toxic and persistent in environments, studying the impact of oil contamination on microbial communities in different soils is vital to oil production engineering, effective soil management and pollution control. This study analyzed the impact of oil contamination on the structure, activity and function in carbon metabolism of microbial communities of Chernozem soil from Daqing oil field and Cinnamon soil from Huabei oil field through both culture-dependent techniques and a culture-independent technique-pyrosequencing. Results revealed that pristine microbial communities in these two soils presented disparate patterns, where Cinnamon soil showed higher abundance of alkane, (polycyclic aromatic hydrocarbons) PAHs and TPH degraders, number of cultivable microbes, bacterial richness, bacterial biodiversity, and stronger microbial activity and function in carbon metabolism than Chernozem soil. It suggested that complicated properties of microbes and soils resulted in the difference in soil microbial patterns. However, the changes of microbial communities caused by oil contamination were similar in respect of two dominant phenomena. Firstly, the microbial community structures were greatly changed, with higher abundance, higher bacterial biodiversity, occurrence of Candidate_division_BRC1 and TAO6, disappearance of BD1-5 and Candidate_division_OD1, dominance of Streptomyces, higher percentage of hydrocarbon-degrading groups, and lower percentage of nitrogen-transforming groups. Secondly, microbial activity and function in carbon metabolism were significantly enhanced. Based on the characteristics of microbial communities in the two soils, appropriate strategy for in situ bioremediation was provided for each oil field. This research underscored the usefulness of combination of culture-dependent techniques and next-generation sequencing techniques both to unravel the microbial patterns and understand the ecological impact of contamination.

Preliminary design and off-design performance analysis of an Organic Rankine Cycle for geothermal sources

Geothermal fluid of 90°C and 10kg/s can be exploited together with oil in Huabei Oilfield of China. Organic Rankine Cycle is regarded as a reasonable method to utilize these geothermal sources. This study conducts a detailed design and off-design performance analysis based on the preliminary design of turbines and heat exchangers. The radial inflow turbine and plate heat exchanger are selected in this paper. Sliding pressure operation is applied in the simulation and three parameters are considered: geothermal fluid mass flow rate, geothermal fluid temperature and condensing pressure. The results indicate that in all considered conditions the designed radial inflow turbine has smooth off-design performance and no choke or supersonic flow are found at the nozzle and rotor exit. The lager geothermal fluid mass flow rate, the higher geothermal fluid temperature and the lower condensing pressure contribute to the increase of cycle efficiency and net power. Performance maps are illustrated to make system meet different load requirements especially when the geothermal fluid temperature and condensing pressure deviate from the design condition. This model can be used to provide basic data for future detailed design, and predict off-design performance in the initial design phase.

Experimental and numerical study on the self-balancing heating performance of a thermosyphon during the process of oil production

The thermosyphon has been widely used in various industries due to its high heat transfer efficiency and large heat flux density, it has the significant value and wide application foreground. In this paper, an experimental rig was established to test the self-balancing heat transfer performance of the thermosyphons with three diameters in an unsteady temperature field, which exists in the actual oil production process. The experimental rig was also able to demonstrate how certain factors can impact on the heat transfer performance of thermosyphon. These factors include the diameter of the pipe, angle, with or without working medium and so on. Based on experimental results, a long thermosyphon made of several hollow sucker rods was designed and manufactured, which has been used in the Su 28 Well situated in the Huabei oilfield in China. Experimental results further indicated that the thermosyphon can effectively transfer the required heat of the fluid from wellbore bottom to wellbore top, causing the temperature of wellhead fluid to increase from 22 °C to 39 °C. In addition, a mathematical model is established to simulate the heat transfer process of this thermosyphon. The positive correlation between the simulated results and the experimental data demonstrated the effectiveness of the model. With this model, the heat transfer process of thermosyphon during oil production is simulated, with results indicating that the fluid temperature at the wellhead would increase when the production of oil increases, given a linear tendency pump setting.

Study of Non-Equilibrium Arms Bridge Circuit for Water Plugging of Horizontal Wells in Sandstone Reservoir

In view of rapid water cut increasing and poor oil recovery with banded distribution with high permeability belt in sandstone reservoir of Huabei Oilfield,the electrical bridge technique for water shut-off is proposed. Based on years practice of vertical wells and similarity in Ohms and Darcys laws,the electrical model involved variable resistors series/parallel instead of reservoir distribution,the arm-bridge circuit combined with signal detection. Then response of the circuit by variable water shut-off could be simulated. The results indicated that,the driving pressure and seepage quantity at mid-low permeability channel could be greatly improved by the strong in-depth water-plugging at high permeability channel (L=20~40m),and the low permeability flowrate increased to a maximum of 55.3%. Then the gel dam in-depth fluid diversion technique was verified by water plugging and circuit simulation. The conclusions provided a valuable guidance for horizontal wells development enhanced.

Modified Method for Estimating Geothermal Resources in Oil and Gas Reservoirs

Increasing attention has been paid to the power generated by utilizing hot fluids that are co-produced from oil and gas reservoirs, as well as other geothermal resources. It is thus essential to evaluate the geothermal resource in oil and gas reservoirs accurately. Although there are a number of approaches for determining the geothermal resource associated with oil and gas fields, a lot of problems are yet to be solved. Previous studies on the effects of oil and gas saturation on the geothermal resource were considered; however, it was assumed that the oil and gas saturations were constant during the development, which is not true. To this end, the existing volumetric approach of evaluating geothermal resource in oil and gas reservoirs was modified by considering the change of oil and gas saturation with time. An oil reservoir from Huabei oilfield with a moderately high temperature was chosen as a target reservoir to apply the modified method. The effects of porosity, oil and gas saturations, and reservoir rock type on the geothermal resource were studied and the results compared to existing approaches. Also, the possible energy and income that might be generated from this geothermal system were estimated. The results indicate that the geothermal resource, energy, and possible income have been overestimated by the existing models, and the difference becomes more significant as the oil or gas saturation increases.

A Microbial-enhanced Oil Recovery Trial in Huabei Oilfield in China

This study discusses microbial-enhanced oil recovery (MEOR) application in Unit Jian-12 in Huabei Oilfield, China. The pilot field was a heavy oil reservoir (50°C, 204 mP.s) with high temperature (75.6°C). Unit Jian-12 was undergoing a waterflooding pattern; however, ordinary waterflooding no longer recovered residual oil efficiently that the MEOR method was strongly recommended in the stripper wells in the unit. A series of laboratory studies was conducted prior to the pilot test. The selected microbial consortia exhibited a positive effect on enhanced oil recovery and potential for application. A two-cycle trial was conducted and the production performance of the unit was monitored. The characteristics of crude oil were modified by biodegradation and the fluidity was improved. The residual oil in the formation was stimulated by the metabolic activities and metabolites, which greatly enhanced the displacement efficiency. In addition, an injection profile improvement was also observed in one injector (J 12–14) after the trial, indicating that the MEOR method could improve the heterogeneity of the reservoir and enhance the sweep efficiency. The results in this study were of academic and theoretic significance to microbial-enhanced oil recovery applications in heavy oil reservoirs.

Discussion on Development and Application of Remove Automatic Metering Technology of Oil Well

The conventional dynamometer diagram diagnosis method of rod pumped well has the function to calculate the well yield based on the downhole dynagraph. In recent years, it can substitute for the traditional separator metering mode technically through further development and support to measure the oil well in an automatic and remote manner, analyze the working conditions and alarm in a real time manner, thus simplifying the collection process and improving the metering accuracy and working efficiency. In this paper, the technical and management problems in development and application of automatic metering technology of rod pumped well dynamometer diagram in Huabei Oilfield are discussed and solutions are proposed in order to guide the wide application of such technology in Huabei Oilfield.

Research and Application of Weighing Low Temperature and Mobile Metering Device

The accuracy and stability of dynamometer diagram measurement are key assessment index for this technology. At present, separator measurement data is mostly taken as comparison benchmark for evaluation of dynamometer diagram measurement in Huabei Oilfield, resulting in large error in comparison. In view of existence of gas, water and pressure, gas/liquid separation of produced fluid is followed by separating measurement of gas and liquid. Gas and liquid mixture are measured by flow meter and weighing method, respectively. Higher precision measurement data is obtained. In combination with PLC programming control, this technology can realize fully automatic and continuous measurement. This device has been applied in 126 wells in Huabei Oilfield. Assisted by dynamometer diagram measurement software, point-to-point calibration and correction method of yield measurement is improved[.

Analysis and applications of a two-phase closed thermosyphon for improving the fluid temperature distribution in wellbores

A heat transfer model that exploits the geothermal energy in oil production wells has been developed by considering not only the produced fluid from the oil well, but also its coupling with the formation temperature distribution and the heat transfer characteristics of the two-phase closed thermosyphon. This study shows that the two-phase closed thermosyphon can transfer effectively the required heat from the fluid of high temperature at the wellbore bottom to the fluid of relatively low temperature at the upper part of the wellbore, so that the overall fluid temperature distribution in the wellbore is improved with the fluid temperature near the wellhead being increased. The numerical model has been validated and further improved by comparing the computational results with the real production data from Chu 32 well and Chu 29-11 well of Huabei Oilfield. A number of influencing parameters on the efficiency of the proposed two-phase closed thermosyphon model have also been investigated in this study, which include the working fluid, the fluid production rate of the oil well, the water cut of the produced fluid and the working depth of the thermosyphon.