US Patent 6866048 Method to decrease iron sulfide deposits in pipe lines

This invention provides a method of treating a dry or processed fluid pipe line susceptible to the build-up of iron sulfide deposits by complexing the iron sulfide in the pipe lines. The method of the present invention introduces the composition on a continuous or a batch basis to a gas pipe line. The composition is made of a solution of 1) water, 2) [tetrakis(hydroxymethyl)phosphonium]sulfate or chloride, and 3) a soluble ammonium salt, such as ammonium chloride or the like.