Thermal Desalination Systems: From Traditionality to Modernity and Development

As well known, the basic birthrights of human are the clean air, clean water, healthy food, and green energy. So, clean water is the second important requested need of all living organisms on Earth. To know the importance of water to our human bodies, a deficiency of just 2% in our body’s water supply indicates dehydration. Nowadays, all countries suffer from the problem of freshwater shortage. Despite the importance of clean water for our lives, only 0.01% is available as surface water such as the rivers, lakes, and swamps. These frightening facts have made it a national and humanitarian duty for scientists to research how to overcome the water problem and how to provide alternative sources of safe drinking water using renewable energies. Desalination is the most famous and operative technique used to overcome this problem. In this chapter, the different desalination techniques are reviewed and reported. Also, the solar distillation processes are mentioned with an extended review on the solar distillers. Besides, the application of artificial intelligence in improving the performance of desalination systems is reported. The main conclusions are stated at the end of this chapter

Insights into improved ferroelectric and electrocaloric performance of Ba0.85Ca0.15Ti0.9Zr0.1O3 thick films grown by the electrophoretic deposition

Lead-free Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZT) bulk ceramics have recently gained attention as one of the attractive candidates for electrocaloric cooling due to their large heat absorption capacity induced by electro-structural phase transition near room temperature. However, adiabatic temperature change (ΔT) at room temperature in ceramics has been limited by their relatively low dielectric breakdown strength. Thick films, in this respect, possess the advantages of ceramics (volume) and thin films (thickness). In this work, a systematic ferroelectric and electrocaloric investigation of BCZT thick films, fabricated by electrophoretic deposition combined with laser annealing, has been carried out. Laser annealing at an optimized energy density of 398 W/cm2 has resulted in densely packed grain morphology with no compositional heterogeneities. Analysis of the scaling behavior of dynamic hysteresis revealed that ferroelectric domain reversal in BCZT/Pt has good stability and low energy consumption in the saturation region. The present thick films exhibited larger breakdown strength of 294 kV/cm and recoverable energy storage density of ~7.3 J/cm3 , at least five-fold enhancement compared to the bulk which is stable up to a 4 mm bending radius. The indirect electrocaloric measurements displayed parameters such as a ΔT and entropy change (ΔS) of 2.94 K and 3.1 J kg− 1 K− 1 respectively, for 205 kV/cm which are more than two orders increased compared to the bulk. Higher values of ΔT (1.9 K) at 25 ◦C, refrigerant capacity of 249 J/kg, and responsivity of 0.143 K mm/kV for BCZT/Pt film compared to relevant lead-free ferroelectric thick films elucidate the potential use of these films for solid-state refrigeration applications. The work also presents electrophoretic deposition with laser annealing as an alternative technique to widely studied tape-casting of thick films for electrocaloric studies.publishe

Thermal Performance Evaluation for Two Designs of Flat-Plate Solar Air Heater : An Experimental and CFD Investigations

The main objective of this research was to create two different configurations of a flat-plate solar air heater, namely, Conventional-Case A and Modified-Case B, and develop a three-dimensional computational fluid dynamics (CFD) model using ANSYS R15.0. The purpose of the CFD model was to simulate the heat transfer behavior of the proposed solar air heaters under unsteady conditions. The RNG k-ε turbulence model was employed for this CFD study. The experiments were conducted on sunny days, under the same conditions as the Egyptian climate. The results of the experiments show that the simulated CFD model and the measured outlet airflow temperatures, relative humidity, and velocities of the two tested solar air heaters were compared. The developed model made very satisfactory predictions. Moreover, the deviations between the average CFD outlet air temperatures and the experimental results were 7% and 7.8% for Case B and Case A, respectively. The CFD-simulated average relative humidity was reduced by 31.6% when using Case B compared with Case A, and it was reduced by 28.8% when comparing the experimental data to Case B. Additionally, the average CFD thermal efficiencies obtained for Case B and Case A were 28.7% and 21.6%, respectively, while the average experimental thermal efficiencies for the cases were 26.4% and 18.2%, respectively. The proposed model can be used to design and simulate other solar air heater designs.Peer reviewe

Thermal and entropy behavior of sustainable solar energy in water solar collectors due to non-Newtonian power-law hybrid nanofluids

Introduction: Nanofluids, hybrid nanofluid possesses thermophysical features that boost the fluid performance. This research work is motivated by the utilization of water solar collectors that incorporate non-Newtonian, power-law hybrid nanofluid in a three-dimensional model, considering the two-phase model.Method: The primary objective of this study is to transform the governing equations of the flow model into a set of ordinary differential equations by employing the three-parameters group technique. Based on the innovative discoveries, two models incorporating new associated functions have been successfully developed for two distinct scenarios characterized by the power-law index, n. The impact of physical factors on the velocity profile, temperature distribution, concentration field, and entropy output of the system is clearly illustrated through a variety of graphs.Results: The results indicated that the inclination angle of 20° had the best thermal characteristics compared to other inclinations. The entropy generation reached its maximum value at temperature difference of 13 K due to irreversibility of the system, which indicates that the system is more efficient.Discussion: Furthermore, the increasing percentage in Nusselt number is predicted to be 28.18% when the Prandtl number is taken a range. The Sherwood number enhanced up to 18.61% with a range of Brownian motion. A quantitative comparison is conducted between the present results and the literature in order to validate the superior efficiency of the used method

New Developments in Prevention and Treatment of Pediatric Infectious Diseases

Both adults and children are regularly afflicted by infectious illnesses. We now have a better understanding of their epidemiology, pathophysiology, prevention, and treatment because of new diagnostic techniques. Recently, emerging infections have surfaced, prompting health officials to issue warnings. Furthermore, novel anti-microbial therapies have been identified; however, because of the potential for adverse effects on antimicrobial resistance, it is critical to understand when to utilize these therapies in order to prevent overuse and misuse. In addition, new vaccinations have entered the market, and it is crucial that medical professionals understand how they may affect public health. Also the use of prebiotics and probiotics has emerged now as a preventive measure for pediatric infectious diseases

Performance and control of a reverse osmosis unit integrated with Pelton Wheel to supply emergency electric loads under various operating conditions

Abstract Nowadays, the whole world is moving very quickly into the field of seawater desalination. This is because the world suffers from a lack of potable water. Water and energy are adjoining linked fields. The present work aims at investigating the performance of a reverse osmosis (RO) plant integrated with Pelton Wheel under various operating conditions. The main reason for using Pelton turbine instead of the pressure exchanger (PX) is the low cost of Pelton compared to that of PX. The RO system integrated with the Pelton Wheel was tested under various operating pressures of 650, 700, 750, 800, and 850 kPa. Changing the feed water pressure affects the pressure of the reject entering the Pelton wheel and this, in turn, affects the velocity of the water jet. Also, the impact of varying the feed water salinity (total dissolved solids (TDS) = 400, 500, 600, 700, and 850 ppm) and temperature (20–39 °C) on the permeate and reject of RO was tested. In addition, a theoretical modeling was built to predict the performance of the RO system. The permeate flow rate was increased by raising the RO operating pressures. The permeate flow rate was augmented from 2.5 to 4.3 L min−1 when increasing the operating pressure from 650 to 850 kPa, respectively. Therefore, the permeate flow rate is enhanced by around 72% when increasing the operating pressure by only 30%. Besides, increasing the pressure by 30% (from 650 to 860 kPa) decreased the generated power of the Pelton Wheel by approximately 72% (from 960 to 270 W, respectively). Also, increasing the feed water salinity leads to raise the salinity of RO permeate, and vice versa. The RO permeate salinity is raised from 165 to 285 ppm when increasing the operating pressure from 650 to 850 kPa, respectively. As well, the more the increase in feed water temperature, the more improve in the permeate flux and salinity. The permeate TDS was decreased from 140 ppm at feed-water temperature 20 °C to 56 ppm at feed water temperature 39 °C. In this study, the Arduino program circuit was used to supply the required emergency loads by controlling the pressure values of high-pressure pump due to easy and open code program. Finally, the theoretical modelling results are in good correspondence with the experimental results. The average deviation among the theoretical and experimental results was 3.5%

Experimental study with thermal and economical analysis for some modifications on cylindrical sector and double slope, single basin solar still

Solar stills are considered one of the most thermally eco-friendly and promising solutions for producing potable water in sunny and arid regions. However, they suffer from a disadvantage in terms of their low productivity. Therefore, this study aims to investigate the performance of cylindrical sector solar stills and compare them with double-slope solar stills. The study also presents the enhanced performance of a thermo-economic system by integrating cost-effective and readily available materials. The experiments were conducted in Egyptian climate conditions, with a water depth of 2 cm in the stills basin, using different materials. Under the same operating conditions, the results showed that the accumulated productivities of the cylindrical sector solar stills (CSSS) and double slope solar stills (DSSS), using black fiber and black dye, were 3514 ml/m2 and 3029 ml/m2, respectively, representing an increase of 16.01%. Furthermore, the daily thermal efficiency of the CSSS and DSSS, using black fiber and black dye, were 30.42% and 26.32%, respectively, showing an increase of 15.58%. The cost per liter (CPL) of potable water produced by CSSS, using black dye with black natural-fiber, was approximately 0.0119 US$/L, while it was 0.0137 US$/L for DSSS. Additionally, the payback periods for CSSS and DSSS were 92 days and 106 days, respectively. In all scenarios studied, the daily accumulated productivities and thermal efficiency of CSSS were greater than those of DSSS

Augmenting hemispherical solar still performance: A multifaceted approach with reflectors, external condenser, advanced wick materials, and nano-PCM integration

This study aims at improving the desalination process of hemispherical solar still (HSS). A modified HSS (MHSS) design was developed, incorporating a 35 cm radius hemispherical absorber to heighten vaporization area and sun exposure. The influence of various factors on the MHSS performance was evaluated: wick material (jute cloth vs. cotton wick), rear reflectors for concentrated solar radiation, fan integration for enhanced heat transfer, and a phase change material (PCM) with silver nanoparticles (Ag) positioned beneath the liner. The MHSS design itself achieved a 96 % gain in productivity over HSS. Jute cloth proved to be a more effective wick material than cotton. The MHSS equipped with external reflectors exhibited a significant 120 % improvement in productivity. Furthermore, fan integration within the MHSS resulted in a 172 % productivity increase (11150 mL/m2⋅day compared to 4100 mL/m2⋅day for the HSS). Besides, the enhancement (152 %) was observed with the MHSS incorporating both a fan and a PCM-Ag composite, yielding a total daily freshwater production of 10500 mL compared to 4150 mL for the HSS. These findings suggest that the MHSS design with optimized features, particularly the use of a fan and PCM-Ag composite, offers a promising approach to significantly improve solar desalination performance

Enhancement of the yield of solar still with the use of solar pond: A review

A solar pond (SP) is a remarkable growth of renewable energy technology that has stored solar energy for storage purposes and is used in many solar thermal applications. It is also utilized for many purposes, such as heating, cooling, space heating, air conditioning, and many more. The present paper shows the use of an SP to improve the yield of solar still (SS) by providing hot water through the heat energy stored in it. It also reveals the use of shallow and mini SPs with SS to improve yield. Various future research works on SS using SPs have also been included in this paper. From the current review paper, it was concluded that the SP increases the yield of the SSScopu

PV Powered High Voltage Pulse Converter with Switching Cells for Food Processing Application

In recent years, industries in the suburb have retrofitted their power supply units with solar power supply systems. Using solar power supply systems for various applications, such as food processing, enables energy expense saving. A promising opportunity in the food industry is solar-powered Pulsed Electric Field (PEF) used in the treatment of fruits and their by-products. For this application, a converter is proposed in this paper with a combination of a passive switched inductor cell and a switched capacitor cell. Furthermore, the derived topology possesses an extendable feature. This topology generates high voltage repetitive pulses with a single semiconductor switch and a reduced component count. Dynamic study of the converter is also performed with the derivation of the transfer function. Cost effective, reliable, and simple circuitry are the critical features of this topology. The circuit topology can generate high voltage pulses by increasing the number of switched inductors and switched capacitor cells. A correlation study on the impact of the switched inductor/capacitor cell is also performed and analyzed, which is not usually performed. A 50 W prototype is designed and tested to validate the performance of the converte