Results of field tests and laboratory evaluation have shown that a plastic pre-coated gravel system is a successful method of sand control for both non-thermal and thermal wells. Significant improvements in this process have been made which provide higher compressive strengths, increased quality of coating, greater chemical and thermal stability and higher permeability of the consolidated gravel. These results have been obtained by using higher quality gravel, an improved coating process and improved placement techniques.
Full scale pumping tests and actual field results indicate that this system provides a consolidated gravel pack capable of controlling sand production without impairing fluid production. The use of this type of material even prior to the improvements has provided good sand control in both injection and production wells in the offshore Gulf Coast region for over a year. Field results in the San Joaquin Valley, California have demonstrated that it is also well suited for sand control in moderate temperature thermal wells. Wells using both steam drive and huff-and-puff methods of stimulation which have employed this improved plastic coated gravel have increased production and virtually eliminated bailing of sand.