Fluid Interface Of The Bottom Water Reservoir Gas Cap Control Technology,

In recent years, some gas cap and bottom water reservoirs had been founded and their reserves play an important role in China. Owing to their complexity, there are many problems during their developing. The dynamic chances of gas oil contact (GOC) and water oil contact (WOC) are must be concentrated during the process of their development. Once the chances of GOC and WOC are out of control ,that should bring serious gas coning and bottom water coning problems to production wells. The production rate will decline quickly and the recovery of reservoir will be low. This paper do a series research about dynamic chance of GOC and WOC.The original and dynamic chances of GOC and WOC are determined by static state and dynamic method. The original GOC and WOC are determined by the curve of pressure—deep or capillary pressure curve. The dynamic position of GOC and WOC can be determined by the production data or the fluid contacts in observation wells. The later method was handled to fractured reservoirs, and this article generalizes it to general reservoirs.This article analyses the mechanism of gas and bottom water coning and formulae of critical rate. Because the Li Chuanliang's critical formula of oil well in bottom water reservoir with partition board did not consider the influence of perforation degree, this paper presents a new critical rate formula and it considers more factors than Li's formula.The methods of determined the oil well best perforation interval and critical rate are investigated. And the article analyses the all kinds of insufficiency of the methods in existence, presents an optimization model, which can determines the best perforation interval and critical rate considering the more factors. This optimization model takes into account the heterogeneity of oil layer and the influence of partition board in reservoir. The model is come true by Visual Basic language. Using this method, the best perforation interval and critical rate are determined of 4 oil wells, and the results are more exactly than the results used other methods.Aim at the problem of gas coning and oil coming into gas cap, water flooding barrier on GOC is used to solve to them. The article analyses the mechanism and technical requirement of water flooding barrier, and suggests the guide views about exploitation of gas cap region. The oil and gas coordinated development is another approach to control the GOC effectively. And it needs research the velocity of gas recovery in gas cap, in order to inter coordinate with crude production and keep the position of GOC relative stabilization. Using the numerical simulation, the twp methods are simulated judge feasibility and validity.Owing to WOC raise during reservoir exploitation, the bottom water is coned into the production well and the water cut rises quickly. This article studies the technology of producing the oil and water at the same time and making the manmade partition board under the perforation interval, analyses the feasibilities of both of methods and verity their validity through numerical simulation.