Asphaltene dispersants

For precipitation in the wellbore, mechanical methods, such as rod and wireline scrapers, can be used to remove Asphaltene deposits. Although these methods provide good cleaning and minimal formation damage, their application is limited to the wellbore and does not resolve the problem associated with near-wellbore formation plugging.

Asphaltene deposits are generally removed manually, if present in readily accessible equipment, such as separators and other surface equipment. For tubular and flowline deposits, physical methods can be used depending on the hardness of the deposit, such as pigging, jetting, milling and drilling, however removal techniques also involve chemical methods, for which testing must be carried out to prescribe correct chemicals and concentrations.

In general, testing for asphaltene is carried out according to ASTM standards, which outline procedure for estimating the flocculation of Asphaltenes, and also criteria for determining appropriate dosages for dispering Asphaltene. Once testing has been carried out, treatment can be prescribed, including solvent soaks, with or without tested dispersants, and often the combination of solvents and heating can be effective.