Reducing fouling in heat exchangers
AssigneeNOVA Chemicals (International) S.A.
InventorsPhilippa Hocking, Fazle Sibtain, Eric Cheluget
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Abstract
In the solution polymerization of ethylene co and homopolymers the solution leaving the reactor is heated to separate polymer from solvent and residual monomers. Fouling in the heat exchanger may be reduced by adding to the solution from 0.01 to 100 ppm by weight of a polyoxyalkylene compound of the formula HO—(CH2CH2O)M[CH2CH(CH3)O]N(CH2CH2O)PH wherein M, N and P each represent the average number of repeating units and M is from 0 to 20, N is from 2 to 50 and P is from 0 to 20 and passing the solution through a heat exchanger to increase its temperature by at least 20° C.
Claims13
A process to reduce black specks in a polymer prepared by passing a solution comprising from 5 to 40 wt % of a polymer comprising one or more olefins and from 95 to 60 wt % of solvent comprising one or more C4-8 saturated hydrocarbons at an initial temperature from 150° C. to 225° C. through a heat exchanger to increase its temperature by at least 20° C. by adding to the solution from 0.01 to 100 ppm by weight of a polyoxyalkylene compound of the formula
- HO—(CH2CH2O)M[CH2CH(CH3)O]N(CH2CH2O)PH
- wherein M, N and P each represent the average number of repeating units and M is from 0 to 20, N is from 2 to 50 and P is from 0 to 20.
Dependencies are inferred from the claim text.