Controllable cross linked gel water blockage plugging material

Abstract

The invention relates to a controllable cross linking gel water shutoff and lost circulation material used for oil-gas fields, which can block off a fractured, vuggy or malignant leaking formation and increase the strength and stability of gel. The technical proposal is as follows: acrylamide of certain amount is added into a breaker containing deionized water, after the acrylamide dissolved, N, N-methylene-bisacrylamide and initiating agent are added, the mixture stands still for 1h at room temperature after 0.5h of gelation, therefore, lump gel product is obtained and finally becomes gel particles after granulation, parching and sieving; the gel particles are then soaked in the solution of chromium trichloride, cross linker is fully absorbed in the gel particles, and the obtained material is dried for spare; the product is then added into the solution of polyvinyl alcohol and the packaged gel particles are obtained after packaging 1-3 times and drying; finally the packaged gel particles containing the cross linker are added into the solution of the water soluble polymer HPAM for slow cross linking reaction, thus obtaining quiescent strong gel. The material is characterized by simple manufacturing process, low cost, little filtration loss and good leak tightness and stability.

Description

Technical field: [0001] The invention relates to a controllable cross-linked gel water plugging and leakage plugging material used in oil and gas fields, in particular to a water plugging and leakage plugging material that adopts encapsulation technology to slowly release high-valent metal ions to cross-link polymer HPAM. Background technique: [0002] Treatment of lost circulation is an important factor that increases drilling costs, and the time spent on it accounts for about 10% of the total drilling time, while the treatment time for fractured and karst caves accounts for more than 70% of the treatment time for lost circulation. Due to serious serious leakage, the traditional plugging materials and methods (such as bridge plugging, cement slurry plugging) have their own weaknesses in dealing with fractured and porous malignant leakage, and it is difficult to prevent the leaking layer around the wellbore. It is easy to mix with the formation fluid and flow away after bein...

AI Technical Summary

Problems solved by technology

[0002] Treatment of lost circulation is an important factor that increases drilling costs, and the time spent on it accounts for about 10% of the total drilling time, while the treatment time for fractured and karst caves accounts for more than 70% of the treatment time for lost circulation. Due to serious serious leakage, the traditional plugging materials and methods (such as bridge plugging, cement slurry plugging) have their own weaknesses in dealing with fractured and porous malignant leakage, and it is difficult to prevent the leaking layer around the wellbore. It is easy to mix with formation fluid and flow away after being diluted, so it is difficult for the plugging slurry to form a tight seal with sufficient strength around the wellbore

Drilling workers at home and abroad have developed some polymer plugging materials and supporting plugging technology from the chemical point of view, but there is still no breakthrough in dealing with fractured and karst vugs.

Images