Expanding Test And Application Of Heavy Oil Thermal Recovery In Sudan

At present development of Sudan oilfield, strong bottom water reservoir is abundant, distributed widely, this kind of reservoir's characteristic is high permeability, and the water body is larger. In development process, because of the formation heterogeneity serious, high permeability, formation pressure drop too fast, induce the oil and water interface is coning, bottom water is intrusion, production pressure drop is high, the coning is serious, if don't solve the coning, will seriously affect the development effect.Sudan oilfield began thermal production in 2010, in Sudan, the reservoir almost belong to the bottom water reservoir. FULA oilfield oil area is 5.2 x 104 km2, storage is 70 million tons, belong to the ordinary heavy oil.The reservoir using natural energy exploitation, namely bottom water prodution, single well production capacity is 30?50 t/d.The existing problems, the first, the water cut is rising fast, from less than 10% in the early part of well water cut rises to more than 80%.the second, oil production decline is large, the part of the oil wells are below 10 t/d.Analysis the reason, the bottom water body is in the bottom of reservoir, bottom water propulsion is speed;High viscosity of crude oil, the oil flow rate, flow rate of crude oil flow is far less than water.Reservoir formation permeability good, plus swabbing speed is high, the water coning caused by speed, oil well see water earlier.As a result, the block production demands facing is how to effectively prevent the bottom water coning into or ridge, extend the anhydrous production period, or appear after the bottom water coning phenomenon, how to inhibit bottom water coning speed, avoid well water cut, so as to realize oil field production stable and high yield.Based on Sudan in bottom water reservoir exploitation of heavy oil production problems and technical difficulties, study the reservoir oil-water distribution, and success in thermal recovery pilot test on the basis of research on inhibition of bottom water technology, and transferred to steam drive development, formed a series of effective inhibition of bottom water coning speed, bottom water reservoir exploitation of heavy oil to enhance oil production technology, finally realizes the oilfield production stable and high yield.