Centrealoil--Decompression and augmented injection for water-injection well 

       The water injection wells after long-term water flooding, as clay migration, liquid resistance effect, water locking damage, reservoir scaling as well as the bacteria multiply make reservoir seriously blocked, and this problem is particularly acute in the near wellbore zone, which leads to the high water injection pressure, water injection rate is seriously enough, because the conventional acidizing plugging removal measures effective period is too short, so water injection pressure after the construction rises too fast.

A series of new techniques, such as: the low viscosity active acid technique, compound plugging-removing technique, augmented injection and increase production technique, have developed by our company, with the low viscosity active acid technology is the most representative. The low viscosity acid active technology is specially used to solve the problem of water-injection well decompression and augmented injection. The low viscosity acid is able to effectively dissolve the scaling substance near and far zone of the water-injection well. The active ingredient except with super strong sterilization ability for bacteria, also can effectively prevent the expansion and migration of clay particles, and is able to peel oily water film on the surface of the sandstone. Therefore, after the low viscosity acid active measures, it can make the water-injection well for a long time to maintain a low water injection pressure and high displacement efficiency. The technology in the application of water-injection wells and water injection stations is more than 10 well groups, and has obvious augmented injection effect.

Characteristics:

①The system has antibacterial rate above 99% against sulfate reducing bacteria, iron-bacteria and saprophytic           bacteria, and has no drug resistance.

②The system on the dissolution rate of calcium carbonate scale blockage is over 98%.

③Under the continue scouring, the adsorption time of active matter in reservoir is greater than or equal to 150             days.

④The recovery rate of core in reservoir is more than 20%(except acid sensitive reservoir)

⑤It is suitable for water-injection wells decompression and augmented injection in the sandstone reservoir of              devote high pressure and long-term high-pressure under injection.

                                Centrealoil