Process for removing hydrocarbons from polymer slurries
AssigneeQuantum Chemical Corporation
InventorChieh-Yuan F. Sung
Life of this patent
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Abstract
A highly energy efficient process for removing hydrocarbons from polymer slurries is disclosed. The process includes feeding a hydrocarbon-containing polymer slurry to a flash tank to flash a portion of the hydrocarbon from the slurry. Thereafter, the resulting slurry is fed to a fluid bed dryer wherein additional hydrocarbon is stripped from the polymer. Subsequently, the resulting polymer powder is transferred to a powder silo wherein further hydrocarbon is removed from the polymer utilizing a heated purge gas flowing countercurrent to the polymer powder. The polymer output preferably has a low hydrocarbon content, on the order of 100 ppm or less.
Claims15
A process for removing a hydrocarbon from a polymer slurry comprising the steps of:
- feeding a hydrocarbon-containing polymer slurry to a flash tank operated at a pressure sufficiently above atmospheric pressure, in the approximate range of about 70-120 psig, to flash at least about 80% of the hydrocarbon from the slurry;
- feeding the resulting slurry from the flash tank to a fluid bed dryer operated at a pressure in the approximate range of about 1-2 psig;
- stripping additional hydrocarbon from the polymer in the fluid bed dryer utilizing heated hydrocarbon as the stripping gas;
- transferring the resulting polymer from the fluid bed dryer to a powder silo wherein additional hydrocarbon is removed from the polymer utilizing a heated purge gas flowing countercurrent to the polymer;
- venting the hydrocarbon flashed from the slurry in the flash tank and recovering a major portion of said hydrocarbon in a cooling water condenser;
- and
- collecting from the powder silo polymer powder having a hydrocarbon content below about 100 ppm.
A process for removing a hydrocarbon from a polymer slurry comprising the steps of:
- feeding a hydrocarbon-containing polymer slurry to a flash tank operated at a pressure sufficiently above atmospheric pressure, in the range of about 70-120 psig and at a temperature in the range of about 110.degree.-135.degree. F., to flash at least about 80% of the hydrocarbon from the slurry;
- feeding the resulting slurry from a flash tank to a fluid bed dryer operated at a pressure of about 1-2 psig;
- stripping additional hydrocarbon from the polymer in the fluid bed dryer utilizing heated hydrocarbon as the stripping gas;
- transferring the resulting polymer from the fluid bed dryer to a powder silo wherein additional hydrocarbon is removed from the polymer utilizing a heated purge gas flowing countercurrent to the polymer;
- venting the hydrocarbon flashed from the slurry in the flash tank and recovering a major portion of said hydrocarbon in a cooling water condenser;
- and
- collecting from the powder silo polymer powder having a hydrocarbon content below about 100 ppm.
Dependencies are inferred from the claim text.