Abstract
Water desalination presents a need to address the growing water-energy nexus. In this work, a literature survey is carried out, along an application of a mathematical model is presented to enhance the freshwater productivity rate of a solar-assisted humidification-dehumidification (HDH) type of desalination system. The prime novelty of this work is to recover the waste heat by reusing the feedwater at the exit of the condenser in the brackish water storage tank and to carry out the analysis of its effectiveness in terms of the system’s yearly thermoeconomics. The developed mathematical model for each of the components of the plant is solved through an iterative procedure. In a parametric study, the influence of mass flow rates (MFRs) of inlet air, saline water, feedwater, and air temperature on the freshwater productivity is shown with and without the waste heat recovery from the condensing coil. It is reported that the production rate of water is increased to a maximum of 15% by recovering the waste heat. Furthermore, yearly analysis has shown that the production rate of water is increased to a maximum of 16% for June in the location of Taxila, Pakistan. An analysis is also carried out on the economics of the proposed modification, which shows that the cost per litre of the desalinated water is reduced by ~13%. It is concluded that the water productivity of an HDH solar desalination plant can be significantly increased by recovering the waste heat from the condensing coil.
Highlights
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.Water covers almost 71% of the total Earth’s surface [1]
The authors concluded that the waste heat from any industrial source as to be used to run the desalination unit and the total cost per litre of fresh water can be around $0.01 considering hot water as an input source driven from the gas turbine
A simulation is carried out for the humidification-dehumidification (HDH) type of desalination system in which the emphasis is given to the performance of the plant by recovering the heat from the condensing coil by reusing the feed water in the brackish water storage tank
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Narayan et al [16] evaluated the potential of a solar-driven humidification- dehumidification desalination plant for small-scale decentralized water production, presented [17] the thermodynamic analysis of desalination cycles, introduced [18] an experimental investigation on the thermal design of humidification dehumidification desalination system, and presented [19] a thermodynamic balancing of HDH desalination by mass extraction and injection The authors, in their reference work [17], concluded that the air-heated cycles reported in the literature are insufficient, a dehumidifier is more vital than the humidifier to the performance of a conventional water-heated cycle, and the varied pressure systems can have a better performance than a single pressure system. The prime novelty of this work is to present a yearly thermoeconomic analysis of the solar-assisted humidification dehumidification desalination plant by recovering the energy from the wasted feed water enthalpy while considering the local conditions. An economic analysis is presented to reflect the advantages of waste heat recovery in terms of the cost of the desalinated water
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
