How to reduce the wax content in asphalt
Thread Content
Our factory produces straight-run asphalt, and the wax content in the crude oil we use is currently extremely high. The asphalt wax content is at the limit. At the atmospheric and vacuum distillation unit, there are two side streams from the vacuum tower; the temperature at the furnace outlet is around 350 degrees, the vacuum level is approximately 98, and no steam is supplied to the bottom of the tower. Under the current processing conditions, how can we reduce the wax content in asphalt? I would appreciate guidance from experienced colleagues.
It’s quite difficult to rely solely on atmospheric and vacuum distillation; originally, a propane deasphalting unit was designed – do you have the capability for such adjustments there?
I really don’t know what effective methods exist for reducing the wax content in asphalt through atmospheric and vacuum distillation. Viscosity reduction of residue and the addition of aromatic oil to asphalt may help improve asphalt-related performance indicators.
A vacuum distillation unit alone cannot change the distribution of asphaltene wax content; it is best to blend crude oils!
It is a long-standing problem in oil refining; direct vacuum distillation alone cannot solve it. Previously, methods such as viscosity reduction and oxidation were used, but only ordinary asphalt could be produced as a result. If there are heavy aromatic oils, such as sludge or rerefined oil, trying to blend in deeply refined products could work; additionally, solvent dewaxing is a good method for removing wax.
Having been involved in the production of vacuum and atmospheric distillation asphalt for over a decade, there is really no method to reduce the content of residue wax through such distillation processes
Increase the furnace outlet temperature, appropriately increase the steam injection into the furnace tubes, and steam can be blown in at the bottom of the tower as appropriate.
Increase the furnace outlet temperature, raise the vacuum level, and reduce three-line or four-line heat reflux