Control of a cracking furnace

摘要

The heat provided to a cracking furnace is manipulated so as to maintain the actual conversion of a first component in the feed stream flowing to the cracking furnace substantially equal to the desired conversion for the first component. The actual conversion of the first component is determined based on an analysis for the concentration of the first component in the feed stream flowing to the cracking furnace, an analysis of the concentration of the first component in the product stream flowing from the cracking furnace, an estimate of the conversion of the first component and a calculation of the expansion of the feed stream in the cracking furnace. The thus derived actual conversion is compared to a desired conversion with the results of the comparison being utilized in combination with the feed flow rate to manipulate the heat provided to the cracking furnace.