Study Of Sand Control Technologies For Heavy Oil Displacement By Steam At Block QI 40

Currently the recoverable reserve of the heavy oil, specially heavy oil and asphaltic sands achieves 1510×108m3 which is beyond the number of common crude oil. As the decline of the common oil production, the heavy oil will become the main energy resource to compensate the reduction of common oil. In this research, aiming at the problems existing in the process of vapor flooding, on the basis of home and broad investigation of the development experience and advancing front, the combined methods of theory and field practice were used to study the vapor flooding technologies at the heavy oil reservoir. The followings are the achievements:1. After many years of practical detection, a technological system of vapor flooding was formed by the pilot field tests of vapor flooding: technology of long term heat insulation vapor flooding at high temperature; heat-resistant and corrosion-proof lift technology; gas tracer monitoring technology; testing technology at high temperature; layering vapor flooding technology; high temperature stimulation technology and remedial technology at case corrosion wells. All the technologies were used well at the field.2. Two main types of sand production were determined in the Block QI 40 as the packed sands and the shed skeleton sands. The comprehensive stress environment of the packed sands and shed skeleton sands were analyzed including hydrodynamic force, gravity, Van der Waals force and repulsion force of double electrode layers. So were the influencing factors of the fluid inflow extent of packed sands and the thread flowing rate of sands, and there changing laws.3. The critical sand production, hole radius and cumulative sand production were analyzed for the reservoir.4. The vague mathematical model was built for the optimization of the sand control method for Block QI 40. By comparison of the sand control methods and their technological economics with vague decision-making method, the effects of all the important factors inside the weight matrix were considered by the maximum subjugation principle. And with the practical judgment about the suitable extent of all the factors for each type of sand control, the sieve vessel sand control TBS was finally optimized as the reasonable method for the studied block. Experiments showed that the new sand control tool has better permeability than the old one and is more suitable for the features of Block QI 40. It can be extended widely at Block QI 40.