Optimizing Design For Steam Assisted Gravity Drainage Technology

With the increasing demand of oil and decreasing oil reserves, the exploitation of heavy crude oil reservoir becomes much more important. Seeing that conventional thermal production methods can't get a good result, it's very significant to study the steam assisted gravity drainage (SAGD) technology which is a very effective method in developing heavy crude oil reservoirs, especially extra heavy oil reservoirs.This article studied the SAGD technology in two ways. One was theoretical research and the other was numerical simulation. Theoretical research began with the inquiry of temperature field, pressure field and dryness fraction along the injector well. Then the screening of SAGD, vapor extraction (VAPEX), steam and gas push (SAGP) was done. After the creation of theoretical model of SAGD, the viscosity-temperature characteristic of oil, velocity of steam-oil interface, oil and water production rate were studied. Looking on oil rate as an evaluation criterion, orthogonal method was used to investigate how much that several factors influenced the development of SAGD. In the other way, numerical models were created to describe the production progress of dual horizontal wells SAGD and vertical-horizontal wells SAGD and optimize the location of wells and injection-production parameters. In the last, numerical prediction results were contrasted to theoretical calculation results and got a good match, which verified the credibility of numerical prediction results and the feasibility of SAGD applying to exploit extra heavy oil reservoirs.