液态CO2注入混相驱注采井层间产量劈分方法探讨

摘要

CO2 miscible flooding can increase unmoved reserves, especially the effective mobile rate of low-permeability reserves and the recovery percentage of high water cut oilfield, while there is a considerable distance of liquid-liquid displacement in liquid CO2 flooding process. In the evaluation of reserve mobile degree and development effects in liquid CO2 injection displacement pro-cess, the clarification of position corresponding relation of injection/production wells and miscible flooding effects is important work in production management. Based on the miscible flooding mechanism in liquid CO2 injection flooding and seepage theory of liquid-liquid displacement, this paper put forward the prediction and calculation method of layered production of injection/produc-tion wells. According to the injection profile and liquid production profile of the test area of some oilfield, the method can analyze the dynamic corresponding relations of injection/production wells to some degree and provide theoretical reference for the optimiza-tion of injection/production parameters.%通过CO2混相驱油可实现提高未动用储量，特别是低渗储量的有效动用率以及高含水油田提高采收率的目的，而液态CO2的注入驱替过程存在相当距离上的液液驱替。在评价注液态CO2驱替过程的储量动用程度和开发效果中，理清注入井和生产井的层位对应关系以及混相驱效应是开发生产管理的主要工作之一。在注液态CO2驱替过程中的混相驱机理基础上，基于液液驱替条件下的渗流理论，提出了注采井分层产量预测计算方法。通过某油田试验区块中的注入剖面和产液剖面，表明该方法可一定程度上分析注采井间动态对应关系，从而为优化注采参数提供理论依据。