Solvent composition and process for removal of asphalt and other contaminant materials

A method for removing contaminant material from industrial equipment, the method comprising:

• (A) providing a solvent composition comprising:
• i. methyl soyate, wherein the methyl soyate comprises about 25 wt. % to about 35 wt. % of the solvent composition;
• ii. N-methylpyrrolidinone, wherein the N-methylpyrrolidinone comprises about 25 wt. % to about 35 wt. % of the solvent composition;
• iii. an additional solvent, wherein the additional solvent is dipropylene glycol and comprises about 25 wt. % to about 35 wt. % of the solvent composition;
• iv. a diluent comprising diesel fuel, wherein the diesel fuel is not biodiesel fuel;
• v. a cationic surfactant, wherein the cationic surfactant is isostearyl ethylimidazolinium ethosulfate, wherein the isostearyl ethylimidazolinium ethosulfate comprises about 6 wt. % to about 10 wt. % of the solvent composition;
• and
• vi. a dispersant, wherein the dispersant is sulfonated-formaldehyde-based;
• and
• wherein a weight ratio of the solvent composition to the contaminant material is between about 100:1 and about 1:1, wherein the contaminant material comprises at least one material selected from the group consisting of asphalt, heavy asphaltenic materials, hydrogen-deficient carbonaceous materials, coke, tar, heavy oil deposits, hydrocarbon sludge, lube oil, and any combination thereof,
• (B) contacting the contaminant material with the solvent composition;
• and
• (C) allowing the solvent composition to react with the contaminant material such that at least a portion of the contaminant material is no longer attached to the industrial equipment.