摘要 |
In a method of controlling a process heater (10), a required heat demand is computed, based on the enthalpy of the feed stock and the desired enthalpy of the final product, and then is used as a feedforward portion of the fuel control. An alternative method is based on the assumption that the feed stock enthalpy changes slowly or infrequently. In the alternative method, fuel heating value changes are used as a feedforward portion of the fuel control. |