Production Optimization Research Of Super Heavy Oil In Dual Horizontal Wells SAGD

The development and utilization of super heavy oil have got more and more attention,owing to the increasing demand of oil resource coupled with the reduction of conventional oil and gas reserve.Steam-Assisted Gravity Drainage is an advanced technology of producing super heavy oils.Owing to its high oil recovery,SAGD is more and more widely used in heavy oil recovery.It's very important to study the steam assisted gravity drainage(SAGD)technology which is a very effective method in developing heavy crude oil reservoirs,especially in super heavy oil reservoirs.This article studies the SAGD technology in two ways.One is the theoretical research and the other is numerical simulation.With the development of SAGD.The SAGD yield prediction model needs a higher demand.In this paper,the research status of SAGD production forecasting model is investigated.The existing models were studied and improved in this paper.On the basis of the existing model,a new model of surface yield prediction is established.?Butler drainage model was studied.Oil production rate was calculated in its rising and horizontal expansion phase.Then the Butler model is modified.Draw the yield curve.?Surface drainage model was studied.On the basis of linear model,considering the actual shape of the steam chamber is an irregular surface.The output of the steam chamber in the lateral expansion phase is derived.The effects of porosity and reservoir thickness on oil production rate were discussed.A method is deduced to calculate the length of the steam chamber at the boundary interface.Draw the yield curve of different stages.Using numerical simulation software CMG to establish the numerical model of SAGD reservoir in dual horizontal wells,the expansion of different stages of steam chamber is analyzed,numerical simulation results are obtained.The effects of reservoir thickness,reservoir porosity,reservoir permeability and reservoir interlayer these different geological parameters on SAGD were analyzed by simulation.When the reservoir thickness is greater,the porosity is higher,the permeability is higher.There is a better SAGD effect,The effect of small scale interlayer on SAGD is small.Optimization of steam quality,steam rate,steam temperature and production-injection ratio these production parameters are implemented.The result is as follows.The optimized steam quality is 0.8,the optimized steam rate should be controlled between 150m~3/d and 200m~3/d,the optimized production-injection ratio is 1.3,steam temperature has little effect on SAGD when compared to steam quality,the steam temperature is above on 240 ?.