Downhole sludge removal

A composition for downhole dissolution of a hydrocarbon sludge in a subterranean formation, the composition comprising:

• an organic solvent configured to dissolve at least a first portion of an organic phase of the hydrocarbon sludge;
• a surfactant;
• an organic acid configured to dissolve at least a portion of an inorganic phase of the hydrocarbon sludge, wherein the surfactant and the organic acid are synergistically configured to increase solubility of the hydrocarbon sludge upon exposure to the composition, wherein the organic acid is lactic acid;
• a mutual solvent that is soluble in oil and in water, wherein the mutual solvent is configured to dissolve at least a second portion of the organic phase of the hydrocarbon sludge, wherein the mutual solvent is configured to increase solubility of the organic acid in the composition;
• and
• a carrier fluid comprising diesel.

A system comprising:

• a wellbore formed in a subterranean formation, wherein the wellbore extends at least to a downhole location within the subterranean formation, wherein a hydrocarbon sludge is located at the downhole location;
• a coiled tubing extending from a surface location and into the wellbore;
• a pump configured to flow a treatment fluid through the coiled tubing and to the downhole location;
• and
• the treatment fluid, wherein the treatment fluid is configured to dissolve the hydrocarbon sludge and comprises:
• an organic solvent configured to dissolve at least a first portion of an organic phase of the hydrocarbon sludge;
• a surfactant;
• an organic acid configured to dissolve at least a portion of an inorganic phase of the hydrocarbon sludge, wherein the surfactant and the organic acid are synergistically configured to increase solubility of the hydrocarbon sludge upon exposure to the treatment fluid;
• and
• a mutual solvent that is soluble in oil and in water, wherein the mutual solvent is configured to dissolve at least a second portion of the organic phase of the hydrocarbon sludge, wherein the mutual solvent is configured to increase solubility of the organic acid in the composition.