Suchergebnisse

With the development of humankind, energy demand and climate change have both faced with serious situations now. In order to find new technologies for solving these problems, long core displacement experiment concerning CO2 flooding is conducted with 11 different core samples from N formation in M oilfield. Results show that oil production rate will be greatly improved and the oil recovery can reach nearly 25% by the CO2 huff and puff process using 3 rounds which is much higher than the real recovery factor in M oilfield. Considering the enhanced oil recovery and carbon storage effects generated by this technique at the same time, CO2 flooding is definitely a promising technique with great potential both for sustainable development of oil companies and humankind. For large scale field application, it is suggested that oil companies and governments should provide corresponding support policy concerning further study of this technology. Particularly, further studies should focus on the application of CO2 flooding with other EOR technologies, optimal CO2 injection mode, optimal CO2 injection rate, optimal CO2 injection pressure and so on.

With its abundant reserves in the world, carbonate reservoir has become one of the main targets for future oil and gas development. Accelerating the research and development of carbonate reservoirs is thus significant to enhance the world's energy supply capacity. However, there have been some problems in the evaluation of carbonate reservoirs for a long time, such as low description accuracy of fractured-vuggy bodies, diverse flow patterns, and difficult reservoir simulation and prediction. Compared with traditional manufacturing methods, 3D printing is an advanced manufacturing technology of rapid prototyping. It has the characteristics of short manufacturing cycle, not limited by the complexity of parts, material saving and energy saving, and thus has unparalleled advantages in reservoir rock analysis. In this paper, the carbonate core of Yingmaili region in Tarim Basin was taken as the research object, and the uniaxial compression mechanical properties of three small cores printed with different materials were designed and tested by using KINGS-600 3D photocuring printer and photosensitive resin materials. After that, UV-9400S white resin with the highest strength is selected as the printing material of the full diameter core model of the karst cave. Combined with the CT scanning of the formed samples, the control accuracy concerning the cave morphology of the 3D printed samples was tested which adequately proves that flow experiments can be carried out with 3D printed core samples. At last, the article also analyzes the shortcomings of 3D printing technology, and points out the direction for its large-scale application in the field of oil and gas exploitation. This study can especially provide a reference for the application of 3D printing technology in the field of carbonate reservoir development, and ultimately promote the sustainable supply of oil and gas resources.

With the increasing demand of natural gas in China, its production is extremely important to fulfill the requirement of society. However, in reality, the natural gas production from the gas well in the gas field is often accompanied by the production of formation water. For gas well with low production, the gas flow rate in the well is too low to carry out the formation water from the bottom of the well. The water will thus accumulate in the well bore and the gas production will be greatly diminished. To solve this problem, based on the developing status of M gas field in China, foaming surfactant Z301 is synthesized and then foaming agent ZK3012 is developed through combination of Z301 with CAT after optimization experiments. After that, the compatibility tests are conducted to ensure that ZK3012 can work together well with formation fluids, and the water carrying rate tests are conducted concerning the optimum concentration of ZK3012. Finally, pilot test is conducted in 2 gas wells on site in M gas field, good results are obtained that accumulated water is discharged by foam drainage and the gas well production is increased. Studies demonstrate the main steps involved for application of this technology. In regard to the high external dependence degree of China in gas supply, operators of gas fields should give prominence to related studies of this technology to achieve sustainable development.

Due to its distribution and reserve characteristics, tight oil has become one of the main targets for future oil and gas exploration. The use of waste flue gas for oil displacement can not only reduce carbon emissions but also enhance oil recovery, which is a technology with great prospects nowadays. In this paper, the pore structure of the tight reservoir core was first characterized by scanning electron microscopy and casting thin section test. Based on these foundations, the displacement experiment was carried out on the tight oil recovery modelling platform, and the pressure distribution and recovery percent of reserves by flue gas huff and puff were innovatively characterized. Study shows that the formation pressure can be maintained in a good level by this technology and the final recovery can be improved a lot than depletion exploitation method. Therefore, the flue gas huff and puff is an effective and advanced technology for tight oil recovery. In the end, specific suggestions are also provided concerning future studies on the field application of flue gas flooding for enhanced oil recovery.