Thermoeconomic Optimization of Sensible Heat Thermal Storage for Cogenerated Waste-to-Energy Recovery

Abstract

This paper investigates the feasibility of employing thermal storage for cogenerated waste-to-energy recovery such as using mass-burning water-wall incinerators and topping steam turbines. Sensible thermal storage is considered in rectangular cross-sectioned channels through which is passed unused process steam at 1307 kPa/250°C (175 psig/482°F) during the storage period and feedwater at 1307 kPa/102°C (175 psig/216°F) during the recovery period. In determining the optimum storage configuration, it is found that the economic feasibility is a function of mass and specific heat of the material and surface area of the channel as well as cost of material and fabrication. Economic considerations included typical cash flows of capital charges, energy revenues, operation and maintenance, and income taxes. Cast concrete is determined to be a potentially attractive storage medium.