Heat recover, in a VC plant, is based on increasing the steam pressure from a steam through a compressor as indicated in the figure below. Thus, the temperature of condensation is raised and the steam can be utilized for providing energy to the very same stage it emerged from. Similar to a conventional system of MEB, the vapor developed in the first effect is utilized as the input of heat to the second effect which is generally at a lower pressure. In the last effect, the volume produced is passed to the compressor of vapor, where it is pressurized and its temperature of saturation is increased before its goes back to the effect. A major part of energy input is represented by the compressor and the latent heat is recycled effectively, the potential of providing high PRs is possessed by the process.
Figure: Principle of operation of a vapour-compression (VC) system
Electro dialysis (ED) of Wind energy (Kinetics energy) to electrical energy and thermal energy to be used in a desalination plant
The network represented in the Fig. 13 operates through the reduction of salinity by the transfer of ions from the water compartment under the influence of a potential difference created by electricity. A DC electric field is utilized by the process for removing salt ions in the water. Dissolved salts are included in the saline feedwater which is separated into chlorine ions which are negatively charged and sodium ions which are positively charged. In addition, these ions will shift towards an electrode that is charged opposite. If electrodes are separated by the special membranes, the centre gap existing between them will not have salt as it will be depleted.
Figure: Principle of operation of electrodialysis (ED)
3). Selection of the application (Data, sizes, place) of Wind energy (Kinetics energy) to electrical energy and thermal energy to be used in a desalination plant
According to the requirement and mention as in the above process the selection of application is “Solar distillation”. The natural cycle of water is mimicked by solar distillation in which the sea water is heated by the sun to cause evaporation. The water vapor, after evaporation, is condensed on a significantly cool surface. In general, there are two kinds of wind energy desalination. Photovoltaic cells are used by the former which are capable of converting solar energy to electrical one for powering the process of desalination while solar energy is utilized by the latter one in the form of heat is referred to as desalination powered by solar thermal energy. It can be said that solar thermal energy is renewable energy’s promising application. A system of solar distillation might include two individual devices including the conventional distiller and the solar collector. Usually, systems of indirect wind energy desalination include a commercial plant of desalination which is interlinked to a special or commercial collectors of solar thermal energy.
It can be said that during the phase of desalination system powered by renewable energy, it will be important for the designer to choose a process which is adequate for a specific application. Actually, following factors must be considered for this type of a selection [150]:
The process suitability for the application of renewable energy.
Process effectiveness in terms of consumption of energy.
The necessary fresh water amount needed in a specific application or process in combination with the applicability range of several processes of desalination.
The requirements of seawater treatment.
Equipment’s capital cost.
The necessary land area for equipment installation.
The cost desalination for the fresh water is the great process of the desalination which is based on the renewable energy it is shown in the below table;
Table 2: Table 4 – Cost of renewable desalination processes
Capacity (m^3/d) Energy demand (kWh/m^3) Cost (USD/m^3 ) Develop stage
Solar Still <0.1 Solar passive 1.3-6.5 Application
Solar multiple effect distillation 1-100 Thermal:100
Electric:1.5 2.6-6.5 R&D application
Solar membrane distillation 0.15-10 Thermal : 150-200 10.4-19.5 R&D application
Solar CSP >5,000 Thermal: 60-70
Electric:1.5-2 2.3-2.9 R&D
Photovoltaic reverse |Osmosis < 100 electric: BW: 0.5-1.5 SW: 4-5 BW: 6.5 – 9.1 SW: 12 -15.6 R&D application
Photovoltaic electro dialysis > 100 electric: only BW:3-4 10.4 – 11.7 R&D R&D
wind reverse |Osmosis 50-2,000 electric: BW: 0.5-1.5 SW: 4-5 < 100m^2/d R&D/ Application
Wind mechanical vapor compression < 100 electric: only SW:11-14 5.2 – 7.8 Basic Research
4). Theoretical analyses (Design and calculation) of the required equipment- Cost analysis
Desalination device Design
Figure: Desalination device schematic diagram.
As shown in the above figure the desalination of seawater devices, this device is equipped by the wind turbine that is also supply the electrical converted and it is converted into the wind energy for the electrical storage into the battery, because this battery is provide the power for the control system. Strong brine discharge pumps, suction pump along with water collecting pump that is also shown by the above figure and it is also driven by it. By sea water the suction pump is connected, and to filter the impurities the Y-type filter is used. By the water collection tank the water collected pump is connected to collect the fresh water. To discharge the strong brine, the strong brine discharge pump is used where vertical axis of wind turbine is passes by the link and still with mixing of heater which is creating the liquid of the mixing heating [12].
References of Vapor Compression of Wind energy (Kinetics energy) to electrical energy and thermal energy to be used in a desalination plant
[1] H. Chen and et al, "Chen, H., Ye, Z., & Gao, W. (2013). A desalination plant with solar and wind energy. IOP Conference Series: 072003. doi:10.1088/1757-899x/52/7/072003," Materials Science and Engineering, vol. 52, no. 27, 2013.
[2] Openei.org, "Wind energy," 20 November 2018. [Online]. Available: https://openei.org/wiki/Wind_energy.
[3] Q. Ma, "Wind energy technologies integrated with desalination systems: Review and state-of-the-art," Desalination,, vol. 277, no. 1-3, p. 274–280, 2011.
[4] D. Mentis and e. al, "Desalination using renewable energy sources on the arid islands of the South Aegean Sea," Energy , vol. 94, p. 262–272, 2016.
[5] E. Tzen, " Wind-Powered Desalination—Principles, Configurations, Design, and Implementation.," in Renewable Energy Powered Desalination Handbook, 2018, p. 91–139.
[6] U. Caldera and e. al, "Local cost of seawater RO desalination based on solar PV and wind energy: A global estimate," Desalination, vol. 385, p. 207–216, 2016.
[7] F. Latorre and e. al, "F.J.G. Latorre, S.O.P. Báez, A.G. Gotor, Energy performance of a reverse osmosis desalination plant operating with variable pressure and flow,," Desalination, vol. 366, p. 146–153., 2015.
[8] V. Belessiotis and e. al, "Solar Distillation—Solar Stills," in Thermal Solar Desalination, 2016, p. 103–190..
[9] S. Kalogirou, "2005, Seawater desalination using renewable energy sources,," Energy & Combustion Science , vol. 31, pp. 242-262, 2005.
[10] EA-ETSAP and IRENA, "Water Desalination Using Renewable Energy," ENERGY TECHNOLOGY SYSTEM ANALYSIS PROGRAMME, 2013.
[11] A. Subraman, "Energy minimization strategies and renewable energy utilization for desalination: A review," Water Research, vol. 45, no. 5, p. 1907–1920, 2011.
[12] U. Caldera, "Caldera, U., Bogdanov, D., & Breyer, C. (2016). Local cost of seawater RO desalination based on solar PV and wind energy: A global estimate.," Desalination, vol. 385, p. 207–216., 2016.
