Use of Matrix Balances for Analysis of Exergy Losses in a Combined Heat Recovery System of a Boiler Plant

Abstract

The results of the analysis of exergy losses in separate elements of the installation containing a gas-fired boiler and the combined heat recovery system for heating water and blast air are resulted. It is noted that a complex technique combining the methods of exergy analysis with one of the methods of the theory linear systems is used to determine exergy losses, namely, the method of RP-representation thermodynamic balances in matrix form. When implementing this technique for separate elements of the heat recovery system, the balances of mass, energy and exergy are recorded in matrix form. On the basis of matrix balances the input matrix by means of which total exergy losses in heat recovery system at various operating modes of a boiler are calculated is defined. The results of calculating the relative contribution of exergy losses in each element of the heat recovery system to the total irreversibility of processes in the system at different operating modes of the boiler are analyzed. It is noted that the smallest losses in the main elements of the heat recovery system occur when the boiler capacity is up to 55 % of the installed capacity.