Study on Numerical Simulation of Steam Huff and Puff Based on Deformable Medium Model

Author(s)
Tingting Wu, Research Institute of Bohai Oilfield, CNOOC Ltd.-Tianjin, Tianjin 300452
Yawei Hou, Research Institute of Bohai Oilfield, CNOOC Ltd.-Tianjin, Tianjin 300452
Fengyi Zhang, Research Institute of Bohai Oilfield, CNOOC Ltd.-Tianjin, Tianjin 300452
Wankun Xu, Research Institute of Bohai Oilfield, CNOOC Ltd.-Tianjin, Tianjin 300452
Dawei Wang, Research Institute of Bohai Oilfield, CNOOC Ltd.-Tianjin, Tianjin 300452

Abstract
Deformable medium model mentioned in this paper is that because of cycling rising and declining of formation pressure during steam huff and puff, the rock which experiencing cycling uploading and unloading appear distorted, which made its compressibility greatly changed. Therefore, the main content of deformable medium model is describing the compressibility change regularity. In traditional study about numerical simulation of steam huff and puff, the rock compressibility is considered constant, which doesn’t really reflect the changing of formation energy in the process, and results the predicting of well production and recovery rate are influenced greatly.
In this paper, by using method of theoretical research, experimental analysis and numerical simulation, deformable medium model to simulate the process of steam huff and puff is established on the basis of systematically researching rock deformation mechanism and heavy oil seepage characteristic in deformation medium. History matching, sensitivity analysis and parameter optimization of steam huff and puff on NB oil field are carried out by using the model. Practice indicates that this model can make higher history fitting precision, more reasonable thermal injection parameters and more accurate predict recovery. Comparing with traditional model, the optimized steam injection rate increased 40%, cyclic steam injection volume increased 30%, predict recovery increased 2.3 percentage. Actual development situation proves the model’s reliability.
There are abundant heavy oil reserves in Bohai oilfield, which needs steam huff and puff. The results from traditional model may lead decision-making mistakes, such as determining incorrect productivity, predicting low recovery, so that put off development of such oilfields because of no economic benefit. By using the model, it is more effective to fit history data, optimize injection and production parameters, and more precise to make development plan and predict indicators.

Keywords
steam huff and puff, deformable medium model, rock compressibility, laboratory experiment, numerical simulation

Cite this paper
Tingting Wu, Yawei Hou, Fengyi Zhang, Wankun Xu, Dawei Wang, Study on Numerical Simulation of Steam Huff and Puff Based on Deformable Medium Model, SCIREA Journal of Mine Engineering. Vol. 1 , No. 1 , 2016 , pp. 1 - 9 .

References