Refinery
Propane Deasphalter Deposits
The primary purpose of the propane deasphalter is to remove asphalt residues from lube oil feedstock. Propane deasphalter deposits of waxes and asphalt decrease the efficiency and must be periodically removed.
Chemicals Utilized
Propane Deasphalter Process
This process uses propane to solubilize oils and precipitate asphalt. Because this process requires a high boiling point, efficient heat exchange is necessary.Â
1
Firstly, the vacuum resid is fed into the deasphalter extractor tower.
2
Next, the extractor tower contacts the vacuum resid with warm propane, resulting in insoluble asphalt precipitating out of the oil and collecting on the tower bottom.
3
Asphalt is heated and sent to a flash drum to flash off propane and deasphalted oil (DAO). The DAO proceeds to the stream stripper towers.
4
The mixture of propane and DAO at the top of the extractor tower goes to the propane evaporator columns to recover the propane. Lastly, the bottom DAO stream is fed to the DAO steam stripper towers.
What Problems do the Propane Deasphalter Cause?
Significant amounts of propane deasphalter deposits form during this stage. Process heat exchangers often foul with heavy asphalt deposits, which prevents efficient heat exchange which is essential for the deasphalter. Also, vacuum resid contains heavy asphalt content. Water scale deposits can also form on the cooling equipment in the deasphalter.
Our Chemical Cleaning Solution
The traditional dissolution of asphalt deposits from the heat exchanger bundles requires substantial downtime. The process included removing the bundles and using high pressure washing to decontaminate them. Alternatively, chemical cleaning does not require pulling the bundles. Therefore, increasing the time efficiency of this method. As a result, there is a reduction of lost production time.
1
Dissolve Wax and Asphalt
FQE® Solvent-H+ is used to both chemically decontaminate the heat exchangers, extractor tower and flash drums, as well as dissolve and remove fouling.
2
Remove Scales
Within the propane deasphalter, the cooling equipment can be chemically cleaned of water-born scales using FQE Scale-Solv.
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Degas the Propane Deasphalter
After the removal of waxes, asphalt and scales, the equipment undergoes decontamination and degassing with FQE LEL-Vapor.
