Thermal Optimization of a Solar Thermal Cooling Cogeneration Plant at Low Temperature Heat Recovery

Abstract

A simple cooling cogeneration has been developed by coupling a Kalina cycle system (KCS) with a vapor absorption refrigeration (VAR) system. The working fluid used in this theoretical thermodynamic evaluation is ammonia water mixture. A low temperature heat recovery (150°C-200°C) from engine exhaust gas, solar collectors, or similar can be used to operate the plant. A controlling facility is provided to set the required amount of power or cooling to meet the variable demand. In this proposed plant, the liquid refrigerant absorbs more amount of heat from evaporator surroundings with a flow control located in betw^een power and cooling cycles. The extra included components are condenser, heat exchanger and throttling device over KCS plant. Due to possibility of more cooling, it offers high energy utilization factor (EUF). The coupled plant characteristics are studied with changes in mass split ratio, separator vapor fraction, separator temperature, and turbine concentration to develop efficient working conditions. The power mass split ratio is varied from 80% to J00% to run the coupled plant at nearly full load conditions. The separator vapor fraction and temperature are optimized at 45% and 150°C, respectively. It is recommended to maintain the turbine concentration above 0.85 for optimum power and cooling. The maximum cycle EUE and plant EUE are 0.J5 and 0.06, respectively, at 80% power mass split ratio. The specific power and specific cooling at these conditions are 62 kWlkg and 72 kWlkg, respectively.

Thermal and Exergetic Analysis of the Goswami Cycle Integrated with Mid-Grade Heat Sources

“…X valve = m 10 ε 10 − m 11 ε 11 (15) where the subscripts c to the condensing fluid which is used to regenerate the cycle working fluid. The heat losses from the heat exchangers and other components to the ambient are neglected.…”

A novel solar assisted Kalina cycle system for waste heat utilization in thermal power plants

“…Lean‐ammonia concentration at separator outlet is described below 19 : …”

Thermodynamic analysis of a new combined cooling and power system using ammonia–water mixture

“…Hua et al [25] added an evaporator and a subcooler to a Kalina cycle to form an ammonia-water cooling and power system for using mid/low-grade waste heat. Srinivas and his co-researchers [26,27] developed a combined power and cooling system by coupling a Kalina cycle system with an ammonia-water absorption refrigeration system, which characterized that a controlling facility was employed to assign the amount of power and cooling to meet variable demands. Then they [28] also proposed another new combined power and cooling system based on Kalina cycle, in which the ammonia-water turbine exhaust was condensed to saturated liquid and depressurized to a lower pressure and then entered an evaporator to produce cooling effect.…”