Empirical investigation of two designs of incline solar water desalination system

This study presents an energy-exergy analysis of a Humidification-Dehumidification (HD) solar water desalination system. The extensive application of the HD system lies in its low energy consumption and ability to exploit solar energy to supply all the heat energy demands. The unsteady governing equations were solved until the system reached a steady state. The simulations were done with the Euler approach to solving the system of energy balance equations numerically. This study's main goal was to investigate the effect of different configurations of the hybrid system and various operating conditions on the performance of the solar HD water desalination system. The optimum configuration was selected based on thermodynamic and exergy analyses. The effects of important parameters such as inlet water and air mass flow rate in the humidifier and dehumidifier water temperature and mass flow rate on the system's operation were studied. This paper also explored the feasibility of the extra heat as a domestic water heater under various conditions. Based on exergy analysis, it is shown that the solar desalination system with air-water preheater with the power of 1057.9 W had the most exergy destruction in comparison with the two other systems (i.e., water preheater system and air preheater system with the respective exergy destructions of 901.3 W and 75.3 W). Comparing the values of freshwater production, exergy destruction, and exergy efficiency, the solar system with a water preheater was selected as the optimum one.

An empirical evaluation of an integrated inclined solar water desalination system with spray jets variation

Recent decades have seen a shortage of water, which has led scientists to concentrate on solar desalination technologies. The present study examines the solar water desalination system with inclined steps, while considering various phase change materials (PCMs). The findings suggest that the incorporation of PCM generally enhances the productivity of the solar desalination system. Additionally, the combination of nanoparticles has been used to PCM, which is a popular technique utilized nowadays to improve the efficiency of these systems. The current investigation involves the transient modeling of a solar water desalination system, utilizing energy conservation equations. The equations were solved using the Runge-Kutta technique of the ODE23s order. The temperatures of the salt water, the absorbent plate of the glass cover, and the PCM were calculated at each time. Without a phase changer, the rate at which fresh water is produced is around 5.15 kg/m2·h. The corresponding mass flow rates of paraffin, n-PCM I, n-PCM III, n-PCM II, and stearic acid are 22.9, 28.9, 5.9, 11.9, and 73 kg/m2·h. PCMs, with the exception of stearic acid, exhibit similar energy efficiency up to an ambient temperature of around 29°. However, at temperatures over 29°, n-PCM II outperforms other PCM.

This study empirically investigated the performance of four configurations of inclined solar water desalination (ISWD) system for parameters such as daily production, efficiency, system cost, and distilled water production cost. The empirical findings show that in terms of daily productivity improved inclined solar water desalination (IISWD) performed best with 6.41 kg/m2/day while improved inclined solar water desalination with wire mesh (IISWDWM) produced the least with 3.0 kg/m2/day. In terms of cost price of the systems, the control system inclined solar water desalination (ISWD) is the cheapest while IISWDWM is the most expensive system. Distilled water cost price ranges from 0.059 TL/kg, for IISWDW, to 0.134 TL/kg, for IISWDWM system. All the systems are economically and technically feasible as a solar desalination system for potable water in northern Cyprus. Potable water from vendors/hawkers ranges from 0.2 to 0.3 TL/kg.

Water and energy are two inseparable issues that play an important role in human life. The oceans are massive resources of water, but the main problem is their high salinity. Solar desalination systems have been considered as a suitable solution to solve the problem of water deficit and to overcome the environmental problems caused by the conventional water desalination plants. One of the important points in raising the efficiency of solar water desalination systems is increasing the evaporation rate in a system with specified dimensions. The direction of the spraying of seawater in the chamber is one of the effective parameters in elevating the discharged rate of vapor in solar desalination systems. In this study, the effects of other parameters including injection pressure, nozzle outlet diameter, nozzle type, and relative humidity inside the chamber were investigated in both upward and downward injection directions by a mathematical model. The results of the model indicated variations in the rate of vapor generation in upward and downward directions. Also, the effects of other important parameters were studied including injection pressure (in the range of 1 to 5 bar), outlet diameter of the nozzle (in the range of 0.9 to 1.1 mm), type of nozzle (long cone orifice, drilled steel orifice, and sapphire orifice) and relative humidity (within the range of 20% to 60%). Overall, the results indicated increased vapor production at an injection pressure of 5 bar, nozzle outlet diameter of 0.9 mm, long cone orifice nozzle, a relative humidity of 20%, and upward direction.

Experimental investigation of performance of cascade solar water desalination system equipped with internal reflector and concave steps

Chapter 9 - Solar water desalination system

Investigation on solar humidification dehumidification water desalination system using a closed-air cycle

This study investigates the thermo-economic performance of different configurations of inclined solar water desalination for parameters such as daily production, efficiency, system cost and distilled water production cost. The four different configurations considered for this study are as follows; 1. Inclined solar water distillation with bare absorber plate (IISWD) with daily production of 5.46 kg/m2 day and daily efficiency of 48.3%. 2. Inclined solar water distillation with wick on absorber plate (IISWDW) with daily production of 6.41kg/m2 day and daily efficiency 50.3%. 3. Inclined solar water distillation with wire mesh on absorber plate (IISWDWM) with daily production n of 3.03 kg/m2 day and daily efficiency 32.6%. 4. Inclined solar water distillation with bare absorber plate (ISWD). (Control System) with daily production of 3.25 kg/m2 day and daily efficiency of 40.1%. The systems potable water cost price ranges from 0.03 $/L for IISWDW to 0.06$/L for IISWDWM System. All the systems are economically and technically feasible as a solar distillation system for potable water in Northern Cyprus. The price of potable water from water vendors/hawkers ranges from 0.11-0.16 $/L. It is more economically viable to have the rooftop inclined solar water desalination system than procuring potable water from vendors.`

Chapter 8 - Nanoparticles-enhanced energy storage materials in solar thermal desalination

In this study, the evaporation of inlet water as one of the most important parts of the solar desalination system was investigated. Elevating the evaporation rate is one of the important points in increasing the efficiency of solar water desalination systems .The evaporation rate and reduction of the droplets diameter sprayed in the chamber was investigated using the mathematical model. It should be noted that, the effects of different factors namely environmental conditions inside the chamber, including relative humidity and pressure, as well as the initial conditions of the droplet, including temperature, injection pressure and initial diameter were also considered. In this study, the information on a droplet sprayed from the nozzle inside the glass chamber in a downward and upward direction at injection pressures of 1, 3, 5 bar, at temperatures of 60, 65, 70 °C and outlet diameters of 1.1, 1, 0, 9.0 mm of nozzle was used by considering three nozzle types of long cone orifice, drilled steel orifice and sapphire orifice at different relative humidity and pressure values in a glass chamber to determine the favorable conditions for evaporation and fresh water production. The most important goal in solar water desalination systems is increasing the availability of fresh water by producing high-flow rate of vapor. Finally, the best condition for producing fresh water was obtained at the injection pressureof5 bar, the inlet temperature of 70 °C, and the outlet diameter of 0.9 mm of nozzle with a discharge coefficient of 0.9 in upward direction.

A review on evaporation improvement of solar still desalination using porous material

Energetic, exergetic, exergoeconomic, and enviroeconomic analysis of solar dish-integrated water desalination system with various nanofluids

Experimental study on the performance of floating solar desalination system with porous absorbent plate

Investigation of numerical phase transition of nano-enhanced SiC/paraffin wax PCM in solar-assisted water desalination system