Investigation of hot-water flooding after steam injection to improve oil recovery in thin heavy-oil reservoir

• Main Authors: Zhengbin Wu, Huiqing Liu
• Format: Article
• Language: English
• Published: SpringerOpen 2018-10-01
• Series: Journal of Petroleum Exploration and Production Technology
• Subjects: Heavy oil; Steam injection; Hot-water flooding; Enhanced oil recovery; Physical experiment; Numerical simulation
• Online Access: http://link.springer.com/article/10.1007/s13202-018-0568-7

Abstract Cyclic steam stimulation (CSS) is one of the popular methods to recovery heavy oil reserves that play an important role in supplying the energy consumption over the world. To solve the problems during the late CSS, we perform the feasibility study of hot-water flooding (HWF) after CSS with laboratory experiments and numerical simulation. The experimental results revealed the optimized water temperature to conduct HWF is 120 °C and the correct moment to convert is when the oil recovery of steam injection reaches 20%. Based on the geological properties of Jinlou oilfield in China, a series of numerical simulations were run to analyze the influence of several sensitive factors. It is necessary to transform development method because there are large quantities of remaining oil assembling at the inter-well region during the late stage of CSS and this after analyzing the oil saturation, reservoir temperature and oil viscosity distribution. The effect of HWF in reverse-rhythm and compound-rhythm reservoir is satisfactory, but is poor in positive-rhythm reservoir. It is suitable to reservoirs with thickness lower than 5 m and permeability variation coefficient less than 0.3. This study can provide a reference for enhanced oil recovery for thin heavy oil reservoirs after steam injection.