New technology for water plugging with urea-formaldehyde resin

In view of such problems as difficulty in controlling the amount of plugging agents, large waste of the agents and high risks in the process of water plugging in oil/water wells, was research was carried out on composite water plugging system composed of solution-type plugging agents and solid particles; when injecting the water plugging agents, the solid particles in its constantly filtrated out and pluged the water, automatically adjusted its inlet pathways and finally realized even and overall plugging. After systematic study on urea-formaldehyde resin in terms of thickening and solid packing, we developed a new water plugging with urea-formaldehyde resin as the major component. For different plugging requirements, we can adjust the different thickening and packing concentration and realized the seamless plugging integrating deep treatment and perforation plugging. The injection pressure for plugging agent is completely controlled within a safe range and can successfully displace to the desired location, then we can directly shut in the well and wait for setting, which can greatly reduce the operation risks. This technology has many merits and works effectively in the fields.