Improvement in Heat Transfer at Coke Battery Chamber Walls

Abstract

The radiant capacity of triatomic gases such as H₂O and CO₂ is investigated as a function of the density and thickness of the gas layer (the radiant path length). It is established that, when the path length is short, the radiant capacity of carbon dioxide predominates; when it is long, the radiant capacity of water vapor predominates. Assessment of the radiant heat-transfer coefficients in heating ducts, for the example of coke battery chambers at Moskoks, indicates that the heat-transfer of water vapor makes the greatest contribution. It increases with increase in content of water vapor in the combustion products of coke oven gas. Computer experiments confirm that supplying superheated steam (around 5 vol % of the air flux) to the combustion zone increases the radiant heat-transfer coefficients from 91.2 to 106.0 W/m² K. That intensifies coking, with simultaneous decrease in the generation of nitrogen oxides. (This technique is sometimes known as green steam injection.)