Simulation of heat-transfer conditions and development of a method for heating a sinter charge with water preheated using the heat of exhaust gases.

To preheat water for moistening a sinter charge, it is proposed to use a recuperative water heater installed in the gas collector of a sinter machine in the zone of the last wind boxes where the temperature of the exhaust gas reaches the maximum, which allows the maximum effect of water heating. The established dependence of the difference between the final and initial temperature of the charge on its initial temperature indicates that the water heating system in sinter production will be the most efficient at sinter charge temperatures close to 0 °C. Finite-element models for analysis of gas dynamics, heat transfer, and water heating in recuperative water heaters by the exhaust gas in the collector of a sinter machine have been developed. Diagrams of the distribution of the temperature of the fluids and the flow-average temperature of water at the collector outlet in planes located along and across the flow of the exhaust gases are plotted. It is established that the heating of the heat-transfer fluid in the water heater with the tubing parallel to the gas flow from the wind box is more intensive, the outlet water temperature being higher by 12.6 °C compared with the case where the tubing is perpendicular to the gas flow in the collector. The developed method of simulating water heating by the heat of the exhaust gas is intended to determine the rational parameters and design features of the recuperative water heater installed in the collector of a sinter machine. [ABSTRACT FROM AUTHOR]