Performance analysis of non-contact nanostructure solar desalination system by varying water depth at a constant air gap

ABSTRACT The consumption of clean water has increased directly to population growth. Therefore, several studies are being conducted to enhance clean water production. Solar distillation is one of the ways to enhance the productivity of pure water. The primary objective of this study is to increase the productivity of pure water using nanofluids and to determine the optimal nanofluid concentration. In the present study, cerium oxide (CeO2) is employed as a nanoparticle in the preparation of nanofluids with concentrations of 0.02%, 0.04%, and 0.06%, respectively. In comparison to conventional solar still (CSS), the improved solar still increased its yield by 27.40% on day 1 (D1), 11.91% on day 2 (D2), and 9.70% on day 3 (D3). On three consecutive days, the maximum daily distillate yield was 860 ml, 761 ml, and 735 ml at concentrations of 0.02%, 0.04%, and 0.06%, respectively. Compared to a concentration of 0.06%, the improved solar still with 0.02% nanoparticles generates 17% more distillate. The cost per liter of CSS and MSS was 0.0756 and 0.0634 USD, respectively. The cost per liter of MSS was 19.21% less in contrast to its counterpart CSS. Water quality analysis was also reported due to the nanofluids harmful nature to humanity, and the results were within acceptable limits set by WHO. Further, we compared the results of the current study with the previously reported literature for the benefit of the researchers.

Amplification of productivity of distillate using cerium oxide nanofluid in solar powered desalination

The production of drinking water is a critical issue due to the lack of access to clean water and the increasing demands of the environment. One of the main technologies for water purification is solar still. Solar distillation is an economical and ecological alternative for the production of quality distilled water. Many recent researches on the use of nanofluids in solar still have focused on its performance, which subsequently implies an increase in the productivity of the solar still, whereas thermophysical and evaporation properties of the base fluid are changed by suspended metallic or non-metallic nanoparticles. According to some reports, the use of nanofluids can raise the distillate productivity up to 100%, other works revealed an improvement up to 20% in terms of thermal efficiency compared to the Conventional solar still. The current review summarizes previous works that studied the improvement of solar still productivity using nanofluids, a significant portion of analysis and discussion is devoted to how different factors affecting the global performance of these devices including nanofluids proprieties, radiation absorption, evaporation and condensation. Finally, propositions for future numerical and experimental research and application guidance are also presented. 

Solar still productivity improvement using nanofluids: A comprehensive review

The increasing need for clean water can be attributed to a number of reasons, such as population growth, industrial development, and climate change. As a result of modern industrial and agricultural methods, the amount of trash generated daily is also on the rise. Waste management and increasing demand for freshwater are two of the most pressing problems facing the human race today and in the future. This study makes an attempt to strike a balance between these two concerns by repurposing a common biowaste, the banana stem, to collect solar energy for a desalination application. Banana stems work well for interfacial solar desalination because of their capillarity and the fact that they float. Camphor-soothed banana stems were placed in a solar still to collect solar thermal energy and to transfer it to the water surrounding them, speeding up the evaporation process and resulting in more freshwater. Over the course of three days, measurements were taken with the water level held constant and the stem thickness of the bananas varied between 0.5 and 1.5 cm. Enviro-economic studies and water quality analysis were used to calculate greenhouse gas emissions, carbon dioxide mitigation, and the carbon credits obtained. Compared to a standard still, a maximum yield of 934 mL was achieved at an efficiency of 36.35 percent. The CPLs (costs per liter) for the MSS (modified solar still) and the CSS (conventional solar still) were USD 0.0503 and USD 0.0665. In comparison to its CSS counterpart, the MSS had a CPL that was 32.21 percent lower. The treated water retained a 95.77% reduction in TDS compared to salt water. The MSS is predicted to release 219.62 kg of carbon dioxide, 1.67 kg of sulfur dioxide, and 0.69 kg of nitrous oxide over its lifetime. In addition, the MSS saved USD 20.94 in carbon credits after avoiding the emission of 2.09 tonnes of CO2.

https://www.mdpi.com/2076-3417/13/3/1652/pdf?version=1674887102

Camphor-Soothed Banana Stem Biowaste in the Productivity and Sustainability of Solar-Powered Desalination

Demand for fresh water increases day by day. Solar desalination is one of the promising technologies to meet this demand in an economical fashion which uses solar still. For the current study, single-basin single-slope conventional solar still and a modified single-basin single-slope solar still with inbuilt condenser and agitator were designed and fabricated. Both the stills were tested under the same ambient conditions to compare the performance. Through experimental results, it was found that modified still with inbuilt condenser and agitator had 98.69% more productivity than conventional solar still. Modified still productivity was recorded as 4.856 L/m2/day and that of conventional still was 2.44 L/m2/day. The agitation effect caused by the agitator in the modified still led to an increase in the rate of evaporation. The increase in condensing area for the same evaporation area of the modified still improved the condensation rate. These two synergized effects resulted in an overall performance improvement of the modified still over the conventional still. An energy analysis revealed that modified still is 24.42% more efficient than its counterpart. The energy efficiency of modified and conventional stills was calculated as 4.82% and 2.04% respectively. 

/pdf/performance-comparison-of-solar-still-with-inbuilt-condenser-30ed2g9n.pdf

Ajay Kumar Kaviti

Papers

Advanced design techniques in passive and active tubular solar stills: a review

Performance analysis of non-contact nanostructure solar desalination system by varying water depth at a constant air gap

Development of nano structures for solar driven desalination