General introduction
The company uses nanomaterials as the main components for the preparation of the plugging agent, which offers good rheological performance. The material hardens and achieves shutoff after injection into the target zone. This plugging agent is high temperature, high pressure and high salinity resistant and is characterized by little bleeding water, high strength, a wide scope of application, a long period of effectiveness and good dissolution.
This technology can be employed to achieve water shutoff for common oil and water wells, the sealing of channeling and casing leaks, as well as the water shutoff of oil wells that need to be reopened for use after the plugging up of high aquifer layers; the shutoff of water injection wells that need to reopened for use after the plugging of strong water accepting layers; stage shutoff for multistage separate injection and the production of wells to be reset by simple string manipulation; the shutoff of heavy oil thermal recovery depleted wells and low temperature wells; the shutoff of high temperature wells, high salinity wells, super deep wells, horizontal wells and other difficult wells.
Its application has been extended to 60 wells in the oilfield, with an average effective period of more than 2 years.
Technical features:
1. High temperature, high pressure and high salinity resistance, long pumpability time, low operational risks;
2. Good rheological performance, low water bleeding, non-shrinking, tight microstructure and high plugging rate;
3. High strength, high dissolution rate, realization of the integration of high strength and a high dissolution rate;
4. Good flushing resistance performance, long period of effectiveness.
高温高压稠化图 high temperature high pressure thickening curve
Technical indexes:
(1)Plugging rate: ≥99.9%
(2) Deplugging/plug removal rate: ≥96.5%
(3) Period of effectiveness: greater than one year
Application results:
Measures and type classification | Site applications | Remarks |
Type of plugging/shutoff | Water shutoff, sealing of external channeling and casing leakage, simplification of well string | Oil wells and water wells |
Type of reservoir | Thin oil and heavy oil reservoirs, natural gas reservoirs | |
Plugged layer well depth | Shallow wells, moderate depth wells, super deep wells | 120-6900m |
Plugged layer well temperature | Low temperature, moderate temperature, high temperature | 18-150℃ |
Well deviation | Vertical wells, deviated wells, horizontal wells | |
Reservoir permeability | Low permeability——seriously depleted open hole wells with high leakage | |
Maximum mineral content of reservoir water | 25.8*10 mg/| | |
Maximum pressure of reservoir fluid | 72.11MPa | |
Maximum downhole temperature | 330℃ | Thermal recovery wells |
The application of the agent has been extended to 22 wells, with an average period of effectiveness of 28 months and a maximum period of effectiveness of 37 months. The effects, in terms of increasing oil recovery, reducing water cut and noneffective water injection, are significant.