Papers by Author: Zhi Ping Li

Abstract: The evaluation of inter-well correlation is an important basis which can instruct engineers to analyze reservoir water-flooding effect, propose the adjustment suggestion. To solve the difficulties of water-flooding evaluation of carbonate reservoir, a new method is proposed based on inter-well connectivity and unascertained math. Firstly, an independent evaluation index system is established before calculating the comprehensive evaluation index weights by the analytic hierarchy process and similarity weight method. Then the Uncertainty measure model is established to evaluate water-flooding effect of well group. This method has been applied in the X oilfield, and good results are gained. The results show that different adjustments should be taken to improve water-flooding effects in different units.

Abstract: The L oilfield Cretaceous (M-I-1), Jurassic Department (Ю-0-3) clastic pore types, including primary porosity, secondary porosity and cracks in three categories, their characteristics and the degree of development. Chalk Department of particles holes and grain dissolution porosity, an average of 53.2%, followed by argillaceous porous and contraction joints, while a small number of particles dissolved pore, showing a small amount of paste particles seam and tensile crack; Jurassic inter-granular holes and intra-granular dissolution porosity is developed, accounting for the porosity as high as 95%, while a small amount of argillaceous porous and granulizing hole and a very small amount of mold holes. L Oilfield Cretaceous and Jurassic reservoirs inter-granular pores, inter-granular dissolution pore, pore throat combination M-I-1, mainly to large - in the hole, micro-throat, Ю-0-3 large - in the hole Extra Coarse - rough throat-based thin throat, Ю-0-1, Jurassic sandstone pore structure better than the Cretaceous.

Abstract: L Oilfield construct as a whole for a wide and gentle anticline, the constructor East steep west slow in constructing the eastern part of the main part of the fault development of the western fault is relatively small, types of traps are faulted anticlines. Type of reservoir rock, siltstone and fine sandstone, sandstone and conglomerate, fine-grained sandstone and siltstone; deposition rhythm is rhythm, including a counter-rhythm, uniform rhythm; Cretaceous reservoir deposition mainly delta plain distributaries channel, the deposition of the Jurassic reservoir delta front, subaqueous distributaries channel and mouth bar; cretaceous reservoir average porosity of 19.3%, average permeability of 30 × 10 - 3μm2, in holes, low permeability reservoir sand body has a more serious layer, flat heterogeneity; Jurassic reservoir average porosity 26%, average permeability of 323 × 10-3μm2 to belong to the hole. in permeability reservoir. Water injection to maintain reservoir pressure development, research to determine the reservoir formation pressure to maintain the level of 0.83 times the original pressure, the initial development technology boundaries with more than 1.2 compensates water injection system pressure of 35MPa.

Abstract: According to many researches, the presence of stress-sensitivity has been confirmed in reservoir rocks. Because it will create huge damage to the permeability of reservoirs, sufficient attention should be made. In this paper, through the experiment, the permeability value change with effective pressure in the condition of saturated with irreducible water and dry environment were compared. The study showed that the stress-sensitivity of core sample was more obvious in the condition of saturated with irreducible water.

Abstract: There are two important features on microstructure of shale.Firstly, Shale rocks are composed of rather fine grained particles, and their pores are very small, at the scale of nanometers.Gas slippage is complicate because its pore diameter is typically less than 10 nm. Secondly, a large amount of shale gas are absorbed in shale the same as coal-bed methane. Adsorbed gas desorption changes the structure. Permeability of shale is dynamic because of Nano-pore structure and desorption of absorbed gas during production. Shale gas slippage dynamic characteristics is researched in Nano-scale pores,based on capillary bundle medle and solid deformation theory. Mathematical model results show that pore diameter and pressure have important effect on permeability. Permeability increases firstly then reduces because of pressure drawdown when pore diameter is less than 10 nm. The lager pore diameter is, the lower pressure point of permeability Inflection and the faster permeability decline rate is. Gas molecular diffusion has less influence on flow when pore diameter is lager than 20 nm and when pressure is lager than 10 MPa. This model can be used for shale gas evaluation and production optimization.

Abstract: The steam flooding is one common way used to enhance oil recovery of heavy oil reservoir. It is difficult to use conventional treatment on steam flooding analysis because of numerous effective factors, complex relationships and no certain mapping relation among those factors. This paper applies grey relationship method to analyze correlative degree of the factors which effect on steam flooding, and then selects steam absorption effect as the comparative indicator, finally gets a sort of steam flooding effect of different parameters. Each correlation degree has a good match with steam flooding effect, and the higher of correlation degree the better of steam flooding effect. Grey relationship is an effective, fast and accurate method for appraising steam flooding effect.