Laboratory Simulation Research On Steam Drive In Qi-40 Block

Qi-40 Block in Liaohe Oilfield was developed by steam-soaking from 1987.The characteristic of crude oil has changed and the old well production has declined as the oil layer pressure decreasing and the long time alternated high temperature effect, while the steam-soaking effect and the economic also been worse. It is necessary to seek the new development method for more oil recovery ratio and the recovery reserve increase. The oil layers in Qi-40 Block are at the depth about 1000m, the middle-deep heavy oil reservoir, while no mature experience about this kind of reservoir can be learned. In this paper, the simulation steam drive experiment about Qi-40 Block has been done for the research of the steam and crude oil movement laws and finding out the major factor for the driving effect. The result can give us the basis for changing the development style in the later stage of the heavy oil steam-soaking method.The heavy oil layer characteristic has been researched of Qi-40 Block experiment district, while it can give the basis for manufacturing the artificial core in the steam driving simulation experiment in the lab. Based on the existing apparatus about steam driving simulation experiment in the lab in Liaohe Oilfield, one new experiment set has been designed and made with the reservoir pressure and temperature and the operation parameter in the stage of changing the driving style taking into account ,which have the oil, gas, water three phases auto-metering systems. The experiment set have the function with auto collecting the data and controlling. This paper focus on the research about the Qi-40 Block physical simulation steam driving experiment in the new set. We have done the experiment on the new apparatus and got some achievements .The displace efficiency of the steam zone is better than the steam- hot water zone ,while the displace efficiency of the steam-hot water zone is better than hot water zone according to the experiment about the displace efficiency on different temperature zone. We can get the conclusion that expanding sweep efficiency of the steam cavity is the important way for better steam-drive efficiency. The fluid mechanic in the layer porous medium showed that us that the saturation of the immobile water increase and the saturation of residual oil by the water drive and the steam drive drop as the increase of the temperature. We can also find that the surface characteristic of the core turn to be water wetly. The oil and water relatively permeability curve about the hot water drive will turn right with the increase of temperature. The oil and water relatively permeability curve about steam drive will be better about the curve shape and the point of inter section will increase. The research result about the Qi-40 Block steam distillation ratio shows that the work mechanic about the steam distillation increase the displace efficiency in the reservoir porous medium is more complex, which is affected by the porous structure and the oil saturation , steam temperature ,steam pressure and the steam injection velocity ,while the steam pressure affect the distillation ratio most. The affect factor experiment about Qi-40 Block steam driving effect shows that that the sand composition and content in the core, steam injection rate and steam quality are the important factors.