5. Industrial production in a tube furnace

Figure 10 shows a highly simplified diagram of the entire plant, which comprises a number of furnaces, quenching boilers and a highly complex fractionation train. The hydrocarbon feedstock enters the hot section of the unit through the convection zone A of the furnace, where it is preheated, then mixed with steam also preheated in the same zone; the hydrocarbons and water then pass through the radiation zone proper of furnace B, where the rapid temperature rise and pyrolysis reactions take place. On leaving the furnace, in order to avoid any further reactions, the effluents are frozen in their kinetic evolution...