... ethane to vacuum gas-oil.This furnace called SCORE,hve straight coils,short residence time about 0.1s nd low working ... furnace is well over 150,000 mta.Pyrolysis heater radiant coil characteristics(single heater range) Number of coils 2-176Coil length ... residence time,s0.1-0.6Coil outlet pressure,KPa150-275Clen coil pressure drop,KPa10-200Ethylene capacity,mta20,000-250,000 Ethylene ...