Experimental study on a self-heat generation and foam system for conformance control

Key words:  self-heat generation foams  resistance factor  conformance control  diversion flow rate

Abstract:

Self-heat generation and foam system (SHGF) can have dual effects of in-situ heating and nitrogen foam, which can be effectively applied for conformance control in oil and gas reservoirs. In this study, A experimental apparatus was designed for studying the mechanism of conformance control of the SHGF system. The experimental results show that resistance factor of SHGF increases with the increase of the permeability of sand packs, and its blocking capability is about twice greater than that of regular foams. The foams generated with the SGHF system in the sandpack can trap more than 90％ of the gas, and the higher of the permeability, the more gas can be trapped, even up to 99％. The SGHF system is effective for conformance control, in which the reversal of diversion flow can be achieved when the permeability ratio ranges from 4 to 16. The time duration for achieving flow reversal increases with the decrease of permeability ratio and lasts longer. Analysis of temperature distribution indicates that the temperature increase from high permeability zone turns to low permeability zone during the displacement, and the phenomena can last longer with the decrease of the permeability ratio, which is in accordance with the diversion flow rate.