Optimization Of Deep Extraction And Dumping System Of Heavy Oil In Tahe Oilfield

The heavy oil in Tahe oilfield reservoir has good fluidity, in the process of lifting up its viscosity increases to be unable to move with the hard heat losing and the temperature decreasing. So most of the heavy oil wells in Tahe oilfield use blending light dropping viscosity technology for producing. The particularity of no implementing large scale water injection leads to the deeper producing fluid level, depth-pumping is one of the key technologies to realize stable production and enhanced oil recovery. The problem in Tahe oilfield is the low oil production, the high mixed thin oil quantity and the high polished rod load with the deeper pump setting depth after implementing blending light oil in annulus. The purpose of this article is improving the system of blending light oil in annulus, studying hollow sucker rod and dual tubing of blending light oil to the adaptation of the heavy oil depth-pumping in Tahe oilfield for solving the production problem.The maximum allowable wellhead viscosity is proposed innovatively to improve the production problem of the annular blending light in Tahe oilfield. The best blending ratio is calculated in different pump setting depth and different rod string assemblage by ensuring the rod string down stroke smoothly and strength requirement to increase the oil production, decrease the thin oil quantity.Due to calculation model of the three technologies’polished rod load the software is programmed and the deep pumping wells’problem of the Tahe oilfield’s production is researched by the three blending light oil technologies, the result shows the dual tubing’s blending ratio is25%less than the annulus’s by the same well parameters and the same rod string assemblage, the dual tubing can save thin oil quantity effectively; hollow sucker blending thin oil technology is not for the deep well; because of the power tubing separating from the producing tubing, the less friction load between rod string and the liquid column result in the less polished rod load, so the dual tubing blending thin oil can solve the blending problems of deep well more efficiently in Tahe oilfield.