emulsify the solvent to form an emulsion and render some of the solvent and acid useless in pickling process another flaw is the large density difference between solvent 7 ppg of density and 15 weight percent hcl 9 ppg of density which tends to enlarge the emulsified interface due to gravitational mixing between the solvent slug and the acid slug this will further incapacitate the pickling slug 39 s effectiveness due to formation of more emulsion at the interface by creating a single slug system which is a dispersion slug of an organic solvent blend and an aqueous pickling acid a dispersant slug which provides efficient cleaning action for removal of both the organic pipe dope contaminants and the iron oxidation and cement scale products by the simultaneous presence of solvent droplets and acid medium in the dispersion slug is provided it also allows substantially full length treatment of a work string for removal of both pipe dope and iron oxidation and cement scale products it is also a simpler treatment utilizing only one slug instead of 2 slugs and also benefits from a larger u201c apparent u201d slug volume by combining the two individual slugs the dispersion system typically contains about 40 to about 70 volume percent of aqueous inorganic hcl h 2 so 4 or organic acid formic acetic acid and about 30 to about 60 volume percent of an organic solvent blend when mixed together under stirring action in a tank and pumped into a work string in turbulent flow the organic solvent blend disperses into droplets in an.