| 摘要 |
A gel-forming composition is provided comprising a first substance selected from the group consisting of a polyvinyl alcohols, polyvinyl alcohol copolymers, and mixtures thereof, a second substance selected from the group consisting of aldehydes, aldehyde generating substances, acetals, acetal generating substances, and mixtures thereof capable of crosslinking with the first substance through the formation of acetal crosslinkages, and water, and which requires contacting with a sorbed substance or brine which has sorbed substantial amounts of carbon dioxide before the gel-forming composition will form a gel. The gel-forming composition is useful for retarding the flow of carbon dioxide and other fluids in subterranean formations. For example, a method is provided for preventing the loss of carbon dioxide to nonproductive parts of an oil reservoir. Such method is particularly useful in carbon dioxide flood operations to increase the sweep efficiency of the oil recovery process and in cyclic carbon dioxide injection operations for increasing the fluidity of the reservoir oil.
|
