Research On Asynchronous Injection-production Mechanism And Parameter Optimization Of Horizontal Wells In Block Mao 15-1

At present,water injection is used to develop low-permeability oil reservoirs in China,but the effect is not significant.After periodic water injection,the oil production effect is improved.However,in the later period of periodic water injection,water breakthrough occurs quickly,water control is difficult,single well production is low,and formations around oil production wells The problem of low energy greatly affects the development of low-permeability reservoirs.Therefore,a set of asynchronous injection-production development technology is proposed in the Mao 15-1 test block.Using the research method of numerical simulation,the mechanism and influencing factors of asynchronous injection and production in low permeability reservoirs are studied,and the parameters of injection and production are optimized.In the study of asynchronous injection production in Mao 15-1 block,first,using the information of the horizontal well in Gulongnan and surrounding vertical wells,a 3D geological model of the horizontal well area was established with a grid accuracy of 20×20× 0.2 m,and the grid coarsening was completed with a grid accuracy of 30 × 30 m;secondly,a numerical model was established.,carry out numerical simulation research,complete the history matching of block Mao 15-1,and on this basis,study the distribution range and characteristics of remaining oil in the current development stage of the test block;The core mechanism of asynchronous injection-production is the imbibition of capillary force,and through the study of the influencing factors of imbibition,it can be concluded that asynchronous injection-production technology can play a better effect in the formation with strong water wetness and high capillary pressure,and with the steaming With the increase of well time,the imbibition effect becomes weaker and weaker.In order to further understand the development mechanism of asynchronous injection and production,the seepage field map and pressure field map of asynchronous injection and production development well pattern are compared with those of synchronous injection and production development.It is beneficial to improve the oil recovery rate by replacing the area and replenishing the formation energy in a timely and balanced manner,which is conducive to improving the oil recovery rate.After that,the adaptability evaluation,the influencing factors of development effect and the optimization of injection and production parameters of the asynchronous injection and production technology are carried out.Finally,the parameter optimization results are used.The development effects of synchronous injection-production and asynchronous injection-production are compared,and the results show that asynchronous injection-production can effectively improve the oil production effect of low-permeability reservoirs.The work of this paper not only provides technical support for the adjustment of water injection development in the Mao 15-1 horizontal well area,but also the research results have important guiding significance for the practice of asynchronous injection and mining in low-permeability oil reservoirs.