Physical Experimental Study on the Development Characteristics of Steam Chambers in Horizontal Wells of Offshore Thin Layer Heavy Oil Reservoirs During Steam Flooding

The Bohai Oilfield has huge reserves with viscosity greater than 350 mPa·s, but conventional methods cannot be used for development. In order to effectively utilize this portion of the reserves, this project aims to carry out small three-dimensional physical experiments on horizontal well steam flooding in the Bohai thin layer heavy oil reservoir N oilfield with a viscosity of 2000 mPa·s of 50 ℃ degassed crude oil. A thermal recovery three-dimensional physical simulation experimental device is used to establish an equal proportion physical model. The well layout method of one injection and one production is adopted, and the experimental parameters are determined using similarity criteria based on the actual injection parameters of the oilfield The influence of small well spacing on the development law of steam drive steam chamber in horizontal wells. From the experimental results, it can be seen that large well spacing horizontal wells have long heating time and long heating distance for the reservoir, large heating area for the reservoir temperature, and slow steam breakthrough, which can achieve a longer period of stable oil production and increase production. At the same time, on-site pilot experiments have achieved good development results. Through this study, it effectively guides the efficient development of thermal recovery in N oilfield and similar heavy oil fields in Bohai, providing technical support for the sustainable development of the Bohai oilfield.