TETRAKISHYDROXYMETHYLPHOSPHONIUM SULFATE (THPS) FOR DISSOLVING IRON SULFIDES DOWNHOLE AND TOPSIDE - A STUDY OF THE CHEMISTRY INFLUENCING DISSOLUTION

摘要

Recently, it has become apparent that THPS, often used as a biocide in oilfield operations, also dissolves iron sulfide scales. The chemistry of this process is reviewed and a study of iron sulfide dissolution, over a range of conditions, is reported. In particular, combinations of THPS with ammonium salts or organic phosphonates are particularly effective and are useful for oilfield situations where iron sulfide scales or suspended iron sulfide particulates are a problem.