Biodegradable foaming agent in drilling and workover operations

摘要

A method for conducting foam drilling and workover oprations in a bore hole penetrating a subterranean reservoir employing an aqueous solution of a biodegradable foaming agent composition containing about 0.1 to 1 part by weight of an N-fatty ethyl sulfate salt having the formula: <IMAGE> wherein R is a straight chain alkyl radical having from 10 to 16 carbon atoms and M is an alkali metal or ammonium cation, per part per weight of a fatty acid salt having the formula: <IMAGE> wherein R1 is a straight chain alkyl radical having from 9 to 15 carbon atoms and M1 is an alkali metal or ammonium cation. A particularly preferred foaming agent composition contains sodium 2-(N-lauryl) ethyl sulfate and sodium laurate.