SAGD low-physical property interlayer acidification transformation method

Abstract

The invention provides a SAGD low-physical property interlayer acidification transformation method. The method includes the steps that a layering injection pipe is deployed in a transformation oil stratum, the upper portion of the lower portion of the interlayer injection pipe are blocked, and the middle of the layering injection pipe is connected with a separated injection valve; transformation liquid is injected into the layering injection pipe, the transformation liquid comprises, by weight, 4-6 wt% of hydrochloric acid, 20-30 wt% of hydrofluoric acid, and the balance water, and the hydrochloric acid, the hydrofluoric acid and the water are used for finishing acidification transformation on an SAGD low-physical property interlayer; according to m rock stratum=rhoV=rho pi R2h/5, the quality of the transformation oil stratum is obtained, the rho is the rock stratum density, and the unit is g/cm<3>; the R is the processing radius, and the unit is m; the h is the thickness of the transformation oil stratum, and the unit is m; the amount of substance of the transformation oil stratum is solved; the consumption amount of HF is solved; finally, the consumption amount of HC1 and water is determined in combination with the HF consumption amount. The SAGD low-physical property interlayer acidification transformation method is reasonable and efficient, low in construction risk and high in success rate.

Description

technical field [0001] The invention provides a transformation method of an interlayer, in particular relates to an acidification transformation method of an SAGD low-physical-property interlayer, and belongs to the technical field of petroleum exploitation. Background technique [0002] The Du 84 Guantao super-heavy oil reservoir in Liaohe Oilfield has now fully entered the stage of SAGD industrialization development. Compared with the initial stage of transfer, the increase in production of the current reservoir has slowed down significantly. [0003] The reasons for the obvious slowdown of the increase in reservoir production were studied, and the results showed that the main factor affecting the development effect of SAGD was the existence of interlayers with low physical properties. Through further in-depth research on the reservoir, it was found that there were multiple sets of interlayers with low physical properties in the upper and lower parts of the steam injection...

AI Technical Summary

Problems solved by technology

Through further in-depth research on the reservoir, it was found that there were multiple sets of interlayers with low physical properties in the upper and lower parts of the steam injection well section. It was the existence of the interlayers that affected the further expansion of the steam chamber or the formation of oil drainage channels, which led to the development of SAGD. It is difficult to further improve the effect, so that the development of SAGD cannot effectively transition from the displacement stage to the stable oil drainage stage. Therefore, it is necessary to strengthen the research on the treatment technology of low physical property interval interlayers

[0004] However, judging from the implementation of the previous fracturing tests, because the interlayer is a low-physical reservoir, the fracturing pressure is relatively high, resulting in a high risk of casing damage, and there is no sign of successful reconstruction. Drilling cannot be carried out due to factors such as SAGD high temperature and inner casing