Study On The Stratified Volume Fracturing Technology In The New Field

The Fifth Member of XuJiaHe Formation in XinChang Gas reservoir have separate layer volume fracturing and commingled production geological conditions, because there are such characteristics as large reservoir thickness, poor physical property, extra-low porosity and permeability, and tight sandstone interbedded with shale reservoirs. But the preliminary reservoir stimulation is not ideal, so it is necessary to study and establish the separate layer volume fracturing technology system adapting to the XU5Formation in XinChang Gas reservoir.In accordance with the difficulties of the XU5gas reservoir separate layer volume fracturing technology, this paper research from the perforation parameters optimization, simulation the induced stress field, the technology of fracture diverted by temporary blocking agent and engineering parameters optimization, and then completed the following work:(1) Considering the original in-situ stress, the fluid pressure in the wellbore, effects of fracturing fluid percolation, temperature variations of rock and impact of perforation, a pressure calculation model is established. And the situation of helical perforation stress interference is simulated by finite element software. Using the rock fracture strength criterion, analysed the effects of perforation parameters on the fracture pressure, and proposed the perforation program of XU5gas reservoir from the perspective of reducing the fracture pressure. Then a optimization method of the perforation position is establish which is based on the brittleness index, natural weak interface and the influencing formation factors of production.(2) A mathematical model used for calculating fracture induced stress field is established. Simulated and analyzed the influence of fracture length, fracture width, fracture interspacing, number of fractures, net pressure within the fracture on fracture induced stress field. And in order to achieve the purpose of separate layer volume fracturing, it can realize by optimizing the friction of perforation to make the multiple fractures breakdown and extend at the same time.(3) Through laboratory experimental means, assessment, evaluated the temporary blocking agent of fiber plugging effect, solubility and reservoir damage, analyzed the impact of the fiber length, fiber concentration, propping agent concentration, fracture width on the temporary blocking effect, formed the technology of fracture diverted by temporary blocking agent which is adapting to the XU5gas reservoir.(4) Based on the ratio of the thickness of sandstone and mudstone, the number of natural fractures, the reservoir is divided into three types of reservoirs, then using Meyer software optimized the fracturing parameters and construction parameters which can be used to guide the separate layer volume fracturing program design.The research results of the understanding of stress interference and the technology of fracture diverted by temporary blocking agent in this paper, it can help improve the XU5 Formation in Xinchang Gas Field multilayer volume fracturing effect, and have a certain application value.