Experimental investigation of a pyramid type solar still with porous material: productivity assessment

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Naresh Yarramsetty ◽  
Naveen Sharma ◽  
Modumudi Lakshmi Narayana

Purpose This study aims to investigate the effect of porous material (clay pots) and it is facing on the productivity performance of a pyramid type solar still. The clay pots are placed in the basin facing up and facing down. The numbers of clay pots considered were 9 and 25, and its performance was compared with normal (0 clay pots) solar still. Design/methodology/approach The pyramid solar water distillation system has been designed, fabricated and tested under the actual environmental conditions of Kanchikacherla (16.6834 0N, 80.3904 0E), Andhra Pradesh, India. The solar still is used to produce the fresh water and hot water simultaneously from the brackish (i.e. containing dissolved salts) feed water for domestic applications. From open literature, it was established that the rate of evaporation is higher when the flowing water is held for a longer duration on the black color absorber plate, thereby leading to an increase in productivity of freshwater. Therefore, the pyramid solar still has been tested for smooth absorber plate and the absorber plate with porous heat storage material. Findings The porous material increases the production rate of freshwater compared to a base plate. However, the pyramid still with clay pots has higher productivity at a lower temperature because of the porosity effect. Originality/value The total dissolved solids, electrical conductivity and pH of the distilled water and the saline water have also been measured and compared.

2019 ◽  
Vol 30 (6) ◽  
pp. 3183-3198 ◽  
Author(s):  
Hamid Reza Goshayeshi ◽  
Mohammad Reza Safaei

Purpose Solar-driven water desalination technologies are rapidly developing with various links to other renewable sources. However, the efficiency of such systems severely depends on the design parameters. This paper presents results from an investigation on the effect of the glass cover inclination angle on the performance of two stepped solar still geometries (flat and convex) and the amount of produced distilled water. Design Methodology Approach Studied inclination angles of 25°, 27.5°, 30°, 32.5° and 35° were chosen, while other design parameters were fixed. Findings The investigation showed that the unit with the convex absorber plate had higher average water daily production rate, compared to the output of the flat absorber plate unit. The results also depicted that the inclination angle of the still has a noticeable effect on the performance of solar stills. The value of the critical angle is 32.5°, and the higher inclination angle results in less heat transfer coefficient. This value can be used for design purposes and erases the typical assumption to use lower angles to optimize the productivity of the still. Practical Implications Finally, obtained data were used to correlate the Nusselt number for the flat and convex surfaces with different inclination angles of the glass cover. Originality Value The outcome of this investigation may find applications to develop highly efficient solar stills to secure more drinkable water in warm, dry lands.


2019 ◽  
Vol 8 (2) ◽  
pp. 6238-6243

Today global warming is a big issue. Ambient temperature have drastically increased, leading to severe droughts especially in those areas which receive less than average rainfall. Inadequate supply of quality drinking water especially in the rural areas have led to develop a distillation system with affordable cost and less maintenance in rural areas. Countries like India and South Africa are getting ample amount of solar energy almost throughout the year. Solar based water distillation unit- Solar still can be great solution to those kind of areas. Efficiency of the solar distillation can be improved by increasing evaporation rate which is a function of incident radiation. Further by increasing concentration of total dissolved salts in the water, base plate absorptivity and efficient energy absorbing material, by providing additional heat with solar water pre-heaters efficiency of solar still can be improved. Here experiments were carried out in order to find out optimum water bath depth and salt concentration in water in solar still for maximizing the yield. Experiments are also carried out by adding heat storage material and effect of salt concentration on yield.


Author(s):  
Md. Raquibul Hasan

The availability of drinking water is reducing day by day, whereas the freshwater necessity is tremendously increasing. There is a need for some sustainable water distillation (purification) to overcome this problem. Solar desalination is a technique used to convert brackish or saline water into potable water, and solar still is a useful device to distil brackish water for drinking purposes. Numerous designs of the solar still system have been developed worldwide. Many researchers outlined mathematical terms, performed experiments and validated the outcome from the various types of solar stills by varying the design and operating parameters. In this article, a review of the active and passive solar stills' performance has been carried out.


2019 ◽  
Vol 286 ◽  
pp. 08007
Author(s):  
M. Bouzaid ◽  
N. Mouhsin ◽  
M. Taha-Janan ◽  
M. Oubrek ◽  
O. Ansari

Morocco is considered as a water-stressed country and is among the countries that face fresh water scarcity. However Morocco has an important solar energy and a significant amount of seawater and ocean. Therefore converting saline water to fresh water using solar energy is the perfect and the cleanest solution. Solar still is the simplest, cleanest and cheapest technology of solar desalination. In this paper a novel solar still with stepped-slope absorber plate and baffles was proposed and developed in order to enhance the thermal performance of the conventional solar stills. In order to validate the performance of the developed technology a comparative study were elaborated. A mathematical model was developed. The energy balance equations for the various elements of the solar still are formulated and numerically solved using the dynamic simulation program Matlab/SimulinkTM and the Euler explicit method programmed by C++. Also, the experimental process of the new construction was evaluated and validates the new pattern performance. The thermal performance was investigated and shows considerable improvement through the new construction.


Author(s):  
Vikrant P Katekar ◽  
Sandip S Deshmukh

Solar still is a cost-effective and environment-friendly device to convert saline water into potable by employing solar energy in developing countries; however, it has an inferior thermal performance. This paper presents an attempt to improve energy efficiency and productivity of solar still by improving the design of the absorber plate. Modified solar still has been tested with a stepped-corrugated absorber plate. During the experimentation, it is found that the thermal performance of modified solar still is superior to conventional solar still. The average basin saline water temperature and the temperature difference between saline water and condenser glass cover are higher for stepped-corrugated solar still by 19.67 and 105.75%, respectively, as compared with conventional solar still. The average energy efficiency, exergy efficiency and productivity are found to be 259.61, 418.61 and 147.93% higher for stepped-corrugated solar still. Economic analysis indicates that the cost of distil water production is approximately Rs. 1.73 (0.023 $) per litre, and the payback period is 12 months, with carbon credits earned are approximately Rs. 11,998 (157.76 $).


2014 ◽  
Vol 592-594 ◽  
pp. 2409-2415 ◽  
Author(s):  
S. Naga Sarada ◽  
Banoth Hima Bindu ◽  
Sri Rama R. Devi ◽  
Ravi Gugulothu

In recent years with the exacerbation of energy shortage, water crisis increases around the world. With the continuous increase in the level of greenhouse gas emissions, the use of various sources of renewable energy is increasingly becoming important for sustainable development. Due to the rising oil price and environmental regulations, the demand of utilizing alternative power sources increased dramatically. Alternative energy and its applications have been heavily studied for the last decade. Energy and water are essential for mankind that influences the socioeconomic development of any nation. Pure water resources become more and more scarce every day as rivers, lakes wells and even seawater pollution rapidly increases. Solar energy is one promising solution to secure power and potable water to future generation. The process of distillation can be used to obtain fresh water from salty, brackish or contaminated water. Water is available in different forms such as sea water, underground water, surface water and atmospheric water. Clean water is essential for good health. The search for sustainable energy resources has emerged as one of the most significant and universal concerns in the 21st century. Solar energy conversion offers a cost effective alternative to our traditional usages. Solar energy is a promising candidate in many applications. Among the alternative energy sources used for electricity production, wind and solar energy systems have become more attractive in recent years. For areas where electricity was not available, stand alone wind and solar systems have been increasingly used. The shortage of drinking water in many countries throughout the world is a serious problem. Humankind has depended for ages on river, sea water and underground water reservoirs for its fresh water needs. But these sources do not always prove to be useful due to the presence of excessive salinity in the water. To resolve this crisis, different methods of solar desalination have been used in many countries. Distillation is a well known thermal process for water purification, most importantly, water desalination. Most of the conventional water distillation processes are highly energy consuming and require fossil fuels as well as electric power for their operation. Single basin solar still is a popular solar device used for converting available brackish or waste water into potable water. Because of its lower productivity, it is not popularly used. Numbers of works are under taken to improve the productivity and efficiency of the solar still. There are large numbers of PCMs that melt and solidify at wide range of temperatures, making them attractive in a number of applications. PCMs have been widely used in latent heat thermal storage systems for heat pumps, solar engineering and spacecraft thermal control applications. The use of PCMs for heating and cooling applications for buildings has been investigated within the past decade. The experimental results computed in the field of water distillation process using solar energy in the presence of energy storage materials sodium sulphate and sodium acetate are discussed in this paper. Keywords: solar energy, saline water, distillation, phase change material.


Author(s):  
Rajendra Prasad Arani ◽  
Ravishankar Sathyamurthy ◽  
Ali Chamkha ◽  
Abd Elnaby Kabeel ◽  
Mageshbabu Deverajan ◽  
...  

Author(s):  
Hamdy Hassan

Abstract In this paper, a theoretical study is presented on enhancement of the solar still performance by using the exhaust gases passing inside a chimney under the still basin. The impact of the exhaust gases temperature on the solar still temperature, productivity, and efficiency are considered. The performance of solar still with chimney is compared with that of conventional solar still. The study is carried out under the hot and climate conditions of Upper Egypt. A complete transient mathematical model of the physical model including the solar still regions temperatures, productivity, and heat transfer between the solar still and the exhaust gases are constructed. The mathematical model is solved numerically by using fourth-order Runge-Kutta method and is programmed by using MATLAB. The mathematical model is validated using an experimental work. The results show that the solar still saline water temperature increases and productivity with using and rising the exhaust gases. Furthermore, the impact of using exhaust gases on the still performance in winter is greater than in summer. using chimney exhaust gases at 75 °C and 125 °C enhances the daily freshwater yield of the conventional still by more than three times and about six times in winter, respectively, and about two and half times and more than three times in summer, respectively.


Sign in / Sign up

Export Citation Format

Share Document