Production Evaluation Method Research Of Dual-well Sagd In Oil Sand

Steam-Assisted Gravity Drainage(SAGD)is one of the most effective way to recover bitumen or viscous oil,and nowadays,there are still two siginificant problems needed to be solved: according to the field data,the drive mechanism for SAGD recovery is not only gravity mechanism,but also injector-producer pressure difference.Therefore,today few papers investigate the effects of injector-producer pressure difference;In the previous prediction model,Butler assumed the steam chamber along the horizontal well was uniformed,however,most of field data reveals that the steam chamber along the horizontal well is not what Bulter thought,and the reality is more complicated and the steam non-conformance is rather common in field.In this paper,the effects of injector-producer pressure difference and the steam non-conformance in SAGD recovery are deeply studied.First of all,based on the geological parameters from Mackay River and Dover reservoir in Canada,a geological numerical model is established.Meanwhile,the effects of pressure difference on oil production rate,stable production time,rising steam chamber and steam chamber expansion are deeply studied.Then a new predictive model considering the injector-producer pressure difference is deduced,since this new model doesn’t have analytical solution,we use the software MATLAB to get numerical solution.This method can achieve fast prediction.Meanwhile,a software is programmed based on the new model.Finally,a series of experiments are conducted to investigate the steam conformance along the horizontal well by ultilizing the self-designed device.A new physical process is proposed based on the experiments’ s results.Based on the results of experiments,combining Darcy’s law and heat conduction along with a mass balance in the reservoir,a new mathematical model considering non-uniform steam distribution is established.What’s more,this new prediction model is verified by numerical simulation and experiment data.According to the steam conformance research,it indicates that the steam quality is also an important factor to influence the steam conformance.This study has great impact on analyizing the effect of pressure difference between injector and producer during SAGD process,and researching on production model with regarding of the steam non-conformance along the horizontal well.