Thermodynamic Analysis of Kalina Cycle

Efficient utilization of the low temperature heat is a challenge. Kalina cycle was proposed to exploit the opportunity of extracting this low grade energy as the conventional Rankine is very inefficient for low temperature applications. In this paper the energy analysis of the Kalina cycle is done. The maximum temperature for the cycle is varied between range 100-200C and the sink temperature for the cycle is assumed as 27C at the exit of the condenser. The model selected for this analysis is KCS-11 owing to its suitably for low temperature application. The pressure is varied between 20-50 bar in steps of 5 bar. The mass fraction of ammonia for composition of ammonia-water mixture is taken 70 %. The efficiency of the Kalina cycle is calculated and tabulated for the heat input of 2 MW to the cycle. The results show that the efficiency of the cycle is solely a function of the separator vapour pressure which is a function of the temperature of the HRVG and has no effect of the HRVG pressure.