Field Application of Lignosulfonate Gels To Reduce Channeling, South Swan Hills Miscible Unit, Alberta, Canada

TLDR: In this paper, a comparison of the total cost of the 9 injector gel treatments with the gross revenues generated by the total calculated incremental oil from the 13 responding producers indicates that the treatments were an economic success.

Abstract: Following initiation by Amoco in 1973 of a secondary miscible (WAG) flood in the South Swan Hills Unit, tracer performance indicated severe channeling of solvent and water, particularly in the northwest quarter of the Unit. In 1975 and 1977, problem zones at 9 injectors were isolated and selectively treated with chrome-lignosulfonate time-set gels in an attempt to reduce solvent and water cycling. The treatment volumes varied between 8500 and 14,000 bbls (1350 and 2225 m/sup 3/) per well. As part of an evaluation of the gel treatments, incremental oil production responses observed at a number of the 56 producers offset to the 9 treated injectors were examined. The responses which could not be explained by other contributory factors, such as the drilling of infill seam injection wells, well workovers (e.g. acid jobs and asphaltene treatments), casing repairs, and pump changeouts, were considered to be the result of improved sweep due to the gel treatments. Thirteen of the 56 offset producers (23%) were found to have responded to the gel treatments, and these were rated as to the duration of response. Response durations of up to 18 months were rated as ''good'', and those lasting longer were rated as ''excellent''. Althoughmore » a detailed economic analysis was not performed, a comparison of the total cost of the 9 injector gel treatments with the gross revenues generated by the total calculated incremental oil from the 13 responding producers indicates that the treatments were an economic success.« less