Augmentation of solar-assisted humidification-dehumidification water desalination system using heat recovery and thermal energy storage system

In previous investigations, humidification-dehumidification (HDH) solar-assisted desalination systems were designed produce the daily fresh water during sun hours which lead to big sizes and unsteady systems. In the present study, integration of solar-assisted HDH desalination system with heat recovery and thermal energy storage unit is developed to enhance system productivity, reduces auxiliary power consumptions and system size and assure system continuous operation. The mathematical modelling based on energy and mass conservation equations is presented and solved using iterative techniques by C++ and engineering equation solver software. Detailed parametric study of the developed system is conducted for wide ranges of operating conditions and design parameters to study the effects of integrating the HDH system with solar collectors, heat recovery and thermal energy storage units on the system performance. The results revealed that (i) this integration improves system productivity and reduces operating cost, (ii) increasing air to water mass ratio and sea water temperature and decreasing ambient humidity decrease water productivity and gained output ratio (GOR) and increase operating cost parameter (OCP) and (iii) increasing air inlet temperature and sea water flow rates increase GOR and decrease OCP. Comparison with previous systems showed that the proposed system reduces the electric heating power of the system at solar noon by 37% at MR = 0.5 and gives daily fresh water productivity (123.7 kg/h) two times more than previous systems with comparable OCP (0.099 $/kg).