The Experiment Study On The Technology Of Removing Plug Of Heavy Oil Reservoir By Steam Huff And Puff

The heavy oil and super heavy oil is very rich in domestic, but due to heavy resin and high asphaltene content witch causing high viscosity, high freezing point and high flow resistance, it is difficult for mining, steam huff and puff is adopted as the main method for mining at present. During thermal recovery process, the structure of reservoir rock is damaged due to the washing of steam and oil leading to amount of sand production in oil well,thereby affected the normal production. In order to meet the development requirements of heavy oil by steam huff and puff, taking the technology of instrument detection, chemical analysis and physical simulation, making Liaohe Shuguang oil field reservoir with its fluid as experimental subjects, organizing experiment by orthogonal experiment design,we carry out the formula optimization of organic deep retarded acid system and the evaluation on plugging effect based on organic chemistry, polymer chemistry and reservoir engineering theory.Range analysis of orthogonal experimental results show that, the best formula system is: A2C3B2D3, namely 45% fluoboric acid, 1.35% anti swelling agent, corrosion inhibitor 3% and iron ion inhibitor 2%; the point of slice hanging experiment is that system of fluoborate acid 3h corrosion rate of the steel sheet was reduced by 45.4%, 6h corrosion rate reduced by 40.2% respectively compared with conventional mud acid, and the 3H dissolution amount of rock soil acid is only the 60% of mud acid; rock core experiment shows the compressive strength of the rock core steeped by fluoboric acid system 10 days is almost constant, but permeability is improved from 20.2μm2 to 35.1μm2, witch indicate the system fluoborate’s performance of improving the permeability of the core, meanwhile having no effect on the firm degree of the formation.