Experimental Study On Mechanism Of Superheated Steam For Different Viscous Heavy Oils

Heavy oils account for a large proportion of the oil resources.We generally use thermal recovery techniques producing heavy oil,steam stimulation and steam drive is a major thermal recovery.Its principle is to use steam as a carrier to transfer the heat to the reservoir,letting the oil heated and then producing heavy oil.As technology advances,the superheated steam has become a new carrier for thermal recovery of heavy oil,which shows a clear advantage in heavy oil recovery.Mechanism of steam and superheated steam is general similar,but there are also many differences.At present,many scholars study the mechanism of action of superheated steam,however,there are rare comparisons and studies on different viscous oils.The viscosity of heavy oils vary from tens to hundreds of thousands,mining methods are different for different viscous heavy oils.on the basis of research,combined with laboratory experiments,I have carried out experimental studies on the mechanism of superheated steam and different viscous heavy oils.Through literature research,we conclude the impact of viscosities' main factors include inner physical properties of the composition and outside physical factors as well as surfactant.And different component content is the most important factor in the viscosity.The superheated steam can change heavy oils' components and elements so that the viscosity of heavy oil reduce permanently.By conducting the aquathermolysis experiments,studied the aquathermolysis of superheated steam and three kinds of different viscous oils,obtained time sensitivity,te mperature sensitivity as well as the change of components and elements before and after aquathermolysis.By designing ordinary steam and superheated steam stimulation experiments,obtained steam stimulation temperature fields diagram and oil production.By contrast,the superheated steam stimulation has a greater range of heat in the reservoir and increase cycle oil production.This thesis have great theoretical significance in producing heavy oil by superheated steam.