International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 2, Issue 5, May 2013
ISSN 2319 - 4847
Effect of different absorbing materials on solar
distillation under the climatic condition of
Manipal
Dr. S. Shanmuga Priya 1*, Umair Iqbal Mahadi2
1
Associate Professor
Department of Chemical Engineering,
Manipal Institute of Technology, Karnataka, India
2
Master of Technology
Department of Chemical Engineering
Manipal Institute of technology, Karnataka, India
ABSTRACT
Solar distillation can be used effectively to produce portable water using sea water, but its low efficiency has restricted its
utilization. It could be still employed at hot climatic geographical locations such as Manipal effectively to produce portable
drinking water. The purpose of this paper is to study the effect of different absorbing materials on distillate production under
the climatic condition of Manipal so as achieve maximum distillate. Single-basin double slope solar still with an effective
insolation area of 0.6m 2 was used to carry out the investigation. Experimental results as expected showed that the distillate
production increased with different absorbing materials as compared to distillate production without any absorbing materials.
Ink and dye were used as absorbing materials and results were compared against distillation with any absorbing materials.
Keywords: Solar distillation, single-basin solar still, direct solar distillation, absorbing materials
*Corresponding author
1. Introduction
Solar distillation can be used effectively to produce fresh drinking water and could play a vital role in preserving nonrenewable energy in coming years. The demand for fresh water is exponentially increasing all around the world due to
population explosion and the rapid industrialization. On the other hand, tremendous increase in population and
industrialization has given problems such as water pollution, energy crisis and global warming which directly affects
the fresh water production. Conventional method of producing fresh water is by burning fossil fuels. But this
contributes to current energy crisis and environmental problems. Hence the need for non-conventional method in future
seems necessary. The basic principles of solar distillation are simple, solar energy heats the water, as the temperature of
water increases, vaporization occurs at the surface of water and water starts evaporating. The evaporated vapors are
condensed at the condensing surface (glass surface). This distillate obtained is free from impurities such as salts and
heavy metals. The evaporation process also kills the micro-organisms, thus giving a portable drinking water. Thus,
solar energy can be important way of meeting fresh water requirement in future in regions with high solar insolation.
Though the knowledge of solar distillation is known for quite a long time, its utilization still remains restricted due to
its very low efficiency. Over the years solar distillation is being used in various ways, among them solar distillation
using solar stills have been commonly used. Several solar still designs have been developed. Studies conducted on solar
distillation using solar still showed that significant improvement in still’s efficiency can be achieved by manipulating
the operating and design parameters suitable to particular climatic condition.
Various designs have been developed over the years [1, 4]. Single slope and double slope single basin solar still have been
intensively used to carry out various studies. The aim of every research on solar stills is to increase the efficiency of
still. Recent attempts and studies shows that the production rate of distillate varies with different designs and with
different geographical location [2]. Studies conducted by J. Joseph [5] evaluate the basic design and operating parameters
affecting the distillate production. Experimental investigation carried out by showed the significant improvement in
distillate production with various absorbing materials [3]. In this research, the effect of different absorbing materials on
Volume 2, Issue 5, May 2013
Page 301
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 2, Issue 5, May 2013
ISSN 2319 - 4847
solar distillation was investigated experimentally under the climatic condition of Manipal during the summer season of
January – April 2013 using a double-slope single basin solar still.
2. Experimental Setup
Solar still with an effective insolation surface area of 0.6m2 was fabricated with dimension as shown in Fig. 1. Nontoughened glass was used as glazing surface with tilted angle of 25°C. Tank was sealed o make it air tight using
silicone gel. The experiments were conducted using raw tap water. The aim of this research was to study the effect of
absorbing materials on the Rate of evaporation in solar distillation conducted under the climatic condition of Manipal.
Each experiment was conducted from 8 am to 8 pm using 30 liters of water in each run. The basin liner of the tank was
coated with black paint. Ink and Black dye were used in water solutions as absorbing materials and results were
compared against the distillation carried out without any absorbing material in the tank water.
Figure 1 Schematic Diagram of Solar still
3. Results And Discussion
Experiments were conducted on 12 hours of daily sun exposure in the month of April under the climatic condition of
Manipal where the average daily temperature remained between 25°C -35°C. During the experiments, Temperature of
water, volumetric production rate of distillate, and level of the water in tank were measured at every hour’s interval.
Effective water depth for distillation was found by carrying out several experiments using black paint on the basin with
different water depths in the tank. It was found that, the depth of 5cm fetched the best results. Hence to evaluate effects
of absorbing materials on distillation, experiments were carried out with water depth of 5cm (30L) using Ink and Dye
in water solution. The effective concentration of absorbing materials to be used in feed water was found out by carrying
out experiments with different concentrations of Dye in water solution. Tests were carried out at 20ppm, 30ppm, 50
ppm and 70ppm concentration of black dye in feed water. The results observed are shown below in fig.2.
Figure 2 Effect of concentration of dye on volumetric flow rate
It was observed that the distillation improved with increasing concentration. Improvement was observed with
increasing concentration of dye from 20 ppm to 50 ppm. Rate of evaporation remained same when the concentration
was increased from 50 ppm to 70 ppm. Hence 50mg of black dye was dissolved in every liter of feed water. Ink was also
used in the same concentration per liter of feed water. Volumetric Rates obtained with Ink and dye was compared
against the results obtained with black paint shown in Fig. 3.
Figure 3 Water collected as a function of the hour of day
Volume 2, Issue 5, May 2013
Page 302
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 2, Issue 5, May 2013
ISSN 2319 - 4847
Figure 4 Cumulative water collected hourly
Figure 5 Temperature profile with different absorbing materials
It was observed that the distillation with ink and black dye improved over distillation with just black pain on the still’s
basin. This refers to absorbing capacity of water increases with addition of extra absorbing materials there by
improving the efficiency of the system.
Among the material used, Black Dye showed the best results by improving the water productivity by almost 65%
whereas Ink in water solution obtained improvement of over 35%. In future study, there could be other materials which
could be used to improve the efficiency of solar still and reduce the effective solar insolation area required which
remain the major problem in solar distillation. Using photo catalyst such Titanium oxide could be used as absorbing
material. Using photo catalyst would also improve the quality of distillate obtained.
4. Conclusion
Results showed that effective solar insolation area plays a vital role in distillate production rate. Adding ink and dye in
water solutions increased the solar insolation area and thereby improving distillate production rate. Dye in water
solutions showed the best result with maximum distillate yield. These absorbing materials reduce the requirement of
effective solar insolation area of a still significantly thereby by reducing the overall cost of fabrication.
5. References
[1.] Imad Al-HayeK, Omar O. Badran, “The Effect of using different designs of solar stills on water distillation,”
Desalination, 169 (2004.) pp. 121-127,
[2.] Kamal, W.A., “A theoretical and experimental study of the basing-type solar still under the Arabian gulf climate
conditions,” Solar and Wind technologies, 5 (1998) pp. 147-157,
[3.] Bilal A. Akash, Mousa S. Mohasen, Omar Osta, and Yaser Elayan, “Experimental evaluation of a single –basin
solar still using different absorbing materials,” Renewable Energy, 14 (1998) pp. 307-310,
Volume 2, Issue 5, May 2013
Page 303
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 2, Issue 5, May 2013
ISSN 2319 - 4847
[4.] Tiwari,G.N., K. Mukharjee, K.R. ashok, and Y.P. Yadav, ”comaparisons of various designs of solar stills,”
Desalination, 60 (1986) pp. 191-202
[5.] J. Joesph, R. Saravanan, S. Renganarayanan, “Studies on a single stage solar desalination system for domestic
application,” Desalination, 173 (2005), pp. 77-82
AUTHORS
Dr.S.Shanmuga Priya is working as an Associate Professor in Department of Chemical Engineering,
Manipal Institute of Technology, Manipal University, Karnataka, India. She has five years of research
experience and four years of teaching experience. She has more than 10 journals, 30 Conferences, 3 book
chapters to her credit in International and National publications. She is also a life member in the Solar
Energy Society of India, Institution of Engineers (I) and Renewable Energy Network (RENET).
Umair Mahadi, received the B.E. Nagarjuna college of engineering and technology in Biotechnology and
currently pursuing M tech degree in Chemical Engineering from Manipal Institute of Technology.
Volume 2, Issue 5, May 2013
Page 304