Experimental Study On A New Type Of Self-propping Fracturing Technology

Hydraulic fracturing technology,as an important stimulation technique for low permeability reservoirs,is widely used in domestic and foreign oilfields.According to lots of literature investigation on fracturing liqud system,proppants,and fracturing technique,we can find that all kinds of changes of fracturing technology are mainly carried out in the following aspects:"sand carrying","fracture initiation",and "proppants placement",and so on.For example:In the study of fracturing fluid system,our purposes is to attain a higher proppants carrying capacity and lower proppants settling rate with the lowest viscosity(minimum friction).But in practical application,it is impossible to improve proppant carrying capacity and reduce the settlement rate,while greatly reducing the viscosity of fracturing fluid.Therefore,it is difficult to escape from this paradox based on the "sand carrying"fracturing fluid system.About the "proppant placement",the mainstream theores are based on the "sand bank" shape of the proppant placement.The circulation channel of oil and gas is mainly composed of pores between proppant particles,and the flow pattern is mainly seepage.To sum up,the conventional fracturing technology is to open the reservoir by fracturing,while the fracturing fluid with solid proppant into the formation of "sand bank" support cracks.In this paper,a new type of self-propping fracturing technology is proposed.The technology is the first to get rid of the concept of carrying sand.In the course of fracturing fluid injection,the solid proppant is not carried.The fracturing fluid and proppant are combined as a whole(after fracturing fluid reaches the target reservoir to form the proppant).Secondly,in the injection process,there is no longer only a single liquid injection.Instead of injecting two liquids simultaneously.The flow behavior of the proppant is controlled by the flow between two phases.In order to obtain the discontinuous and heterogeneous proppant placement.Therefore,the finite seepage is changed into infinite seepage capacity.Greatly improve oil and gas production.