Separate and combined integration of Kalina cycle for waste heat recovery from a cement plant

Abstract

This article reports on using Kalina cycle for waste heat recovery from a cement plant. Two design alternatives have been investigated using separate and combined waste heat recovery from the kiln, cooler, and preheater. Measurements and analysis have been performed to determine the waste heat from different stages of the cement manufacturing lines. The annual heat losses from the kiln surface, preheater, and the cooler are estimated as 79.23 GWh, 44.32 GWh, and 43.6 GWh at average temperatures of about 314?, 315?, and 254?, respectively. Analysis and optimization of using Kalina cycle for waste heat recovery from the kiln shell, cooler and preheater to produce electricity have been carried out using ASPEN software. Parametric study has been carried out to determine the design parameters for Kalina cycle including turbine inlet pressure, mass-flow rate, and NH3-H2O concentration. The value of net power output using combined waste heat recovery is about 7.35 MW as compared to 6.86 using separate waste heat recovery design with a total cost saving of about 23%.