Is there any way to slow coke formation in ethylene furnaces?

Is there any way to slow coke formation in ethylene furnaces?
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Answer :

Westaim Corporation has a commercial process for applying a special coating to the tubes used in  ethylene furnaces. Westaim claims that coke buildup is reduced to one-forth to one-tenth of the normal  rate. The coating consists of a combination of metal, ceramic powder, and a polymer. Once the coating  is applied, the tubes are then heat-treated and reacted with an unspecified gas. Welds cannot be coated  with this process.
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