Fluid injection

摘要

A method is described of injecting CO2 into an aquifer or a depleted hydrocarbon reservoir (211) via at least one injection well (202) that penetrates said aquifer or reservoir, wherein the injection well is provided with an injection tubing (203) that is in sealing engagement with the injection well. The injection tubing terminates at or immediately above the interval of the aquifer or the reservoir into which the CO2 is to be injected and the injection tubing is provided with a fluid injection control valve (208) at or near the bottom thereof which is closed or closes when the pressure above the valve is less than a pre-set pressure value and opens or reopens when the pressure above the valve is at or greater than said pre-set pressure value, the pre-set pressure value being selected such that the CO2 in the injection tubing is maintained in a liquid or supercritical state.

主权项

1. A method of injecting CO2 into an aquifer or a depleted hydrocarbon reservoir via at least one injection well that penetrates said aquifer or reservoir, wherein the injection well is provided with an injection tubing that is in sealing engagement with the injection well and wherein the pressure of the aquifer or the reservoir pressure of the depleted hydrocarbon reservoir is less than the critical pressure of CO2, which method comprises:
operating an injection facility to inject a CO2 stream down the injection tubing of the injection well at above the critical pressure of CO2 at a given temperature, the stream being in a liquid state or a supercritical state; wherein the injection tubing terminates at or immediately above the interval of the aquifer or the reservoir into which the CO2 is to be injected and the injection tubing is provided with a fluid injection control valve at or near the bottom thereof which is closed or closes when the pressure above the valve is less than a pre-set pressure value and opens or reopens when the pressure above the valve is at or greater than said pre-set pressure value, the pre-set pressure value being selected such that the CO2 in the injection tubing is maintained in a liquid or supercritical state.