| 摘要 |
<p>GEL AND PROCESS FOR PREVENTING CARBON DIOXIDE BREAK THROUGH A gel-forming composition is provided comprising a first substance selected from the group consisting of a polyvinyl alcohol, a polyvinyl alcohol copolymer, and mixtures thereof, an aldehyde, and water, and which requires contacting with a brine which has absorbed substantial amounts of carbon eioxide 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.</p> |
