Threedimensional simplified schematization of new solar distillation system by solar energy. These results indicate that the implementation of solar stills is a feasible measure for budunbuto, even though there are some uncertainties. Figure 2 shows a schematic of a passive solar still with regenerative system. The desalination of brackish water by solar radiation systems is a sensible. Solar stills have been considered as one of the viable options of converting brackish or dirty water into distil water. Equations 19 and 21 are evaluated at initial water and glass. This, in combination with the distillate water, would suffice for the drinking water demand of budunbuto when constructing between 3 and 11 berkads with solar stills.
Mathematical modeling of a solar still university of khartoum. Using a solar energy in water desalination system is regarded as one of the most effective ways to resolve the problem of freshwater shortages in this world. Introduction water scarcity is a growing problem for large regions of the world. Therefore, three identical simple basin single slope solar stills a, b, and c. Analytical simulation of energy behavior of solar stills. The external collectors25 are a solar water heater swh, solar air heater, photovoltaic pv. A solar still distills water using energy from the sun. Optimization the performance of single basin solar still. After conducting a research concerning this topic, i found that there are different types of swh, and a type was chosen. Solar desalination for domestic applicationsmehdi n.
Solar stills are usually classified into two categories. Desalination, distillation, solar energy, solar still, sea water, efficiency, electrical conductivity, ph. Mathematical modeling of conventional solar still coupled. Statistical analysis, solar still, double slope, active mode, passive mode. The calculations are based on a solar hot water system with 3m. An empirical equation was derived relating productivity to the intensity of.
The maximum efficiency of this type of solar stills is about 34%, and. Economic feasibility evaluation of solar distillation systems. Solar hot water heaters swh represent one such solar technology capable of cutting significant greenhouse gas emissions. I manual on solar distillation of saline water irc wash. Sep 15, 2009 table 3c linear characteristic equations for a single slope passive solar still at 30 angle of inclination of condensing cover at different brine water depths for the month of june, 2004 sr. The experimental work is based on five diffusive solar stills in operation for several months, where an electrical heater supplies energy to the solar still instead of solar radiation. Design of small photovoltaic pv solarpowered water pump. Performance improvement of a passive solar still in a water. The solar radiant heat after tr ansmitting through a tr ansparent tubular cover is mostly absorbed by water in the trough. Pdf in developing countries, lack of safe and unreliable drinking water constitutes a. The experiments were conducted on different days in the 3.
An experimental study was conducted in a single slope basin solar still after introducing a floating perforated and folded aluminium sheet over the water surface, which concentrates heat energy at. Solar desalination as an adaptation tool for climate. Modeling an active solar still for sea water desalination. As a welldeveloped, renewable technology and relatively lowtech system, solar water heating swh systems provide an efficient method for using the suns energy to heat water u. Evaluation of the implementation of the solar still principle. Theoretical analysis of water distillation using solar still academic. The correspondence between experimental and calculated distillate. Performance analysis of single slope solar stills at. An experimental and statistical analysis of double slope single. Photograph of the new design of solar still with an internal condenser and coupled with solar water and air heater and humidifier.
It acts as a mechanism to separate pure water from the impurities. Typical efficiencies for single basin solar stills. Comparative cost of compact nature of solar stills like single slope, double slope and wick type solar. Design, fabrication and performance evaluation of solar water. L shape solar still produce average distilled water was 925 mlday which was very low among the all type of solar still. The dimensionless water basin number zh which represents the ratio between the thickness of the water film hb in the basin of the solar still and a reference water depth. It has been found that the single slope solar still produced 3. Dec 01, 2014 the solar still is a basin enclosing saline water.
South african heat pipe association solar water heating theory, 24 oct 2008, stias, stellenbosch thermosyphon solar water heating system how does it work. Experimental and theoretical approaches were carried out to design and test multistage solar still. Performance and comparative study of a passive solar still in a forest. The general equation for the rate of evaporative heat transfer between water to. The basic principles of solar water distillation are simple, yet effective, as distillation replicates the way nature makes rain. A thermal model for predicting the performance of a solar still with. They gather the suns energy, transform its radiation into heat, then transfer that heat to a fluid usually water or air. Thermal modeling of passive solar stills is developed resorting to the equations of energy balance, over its constituents. Thermal modeling and efficiency of solar water distillation. The thermal model is based on energy balance equations for the different components of a double condensing chamber solar still dcs, namely the water mass, the first and second condensing covers. The highest efficiency obtained for the solar still wa s 29. Design of solar thermal systems calculation methods. The water vapor density of the humid air increases associated with the evaporation from the water surface and then the water vapor is condensed on the inner.
Brine water depth m linear characteristic equations value of x for threshold intensity i threshold coefficient of correlation r 2 root mean. Consequently, the water is heated up and evaporates. This chapter presents an overview of the solar still. The article concludes by summarizing the prospects for cost ef. Are based on a mathematical model, but are used when the equations. The solar thermal energy can be used in solar water heating systems, solar pool heaters, and solar spaceheating systems. Like the natural hydrological cycle, the sun drives the process of purification. Comparisons of instantaneous gain and loss efficiencies at 0. Jan 01, 2020 in the field of water purification with the application of nanofluid experimented on passive double slope solar still along with water based nanoparticles i. The different angles of inclination of condensing cover 15, 30, 45 have been chosen for winter and summer conditions both. Abstract sun radiation is the heat energy source for solar still. When implementing a solar still on a berkad, the output is estimated to vary between 100 and 590 litres of clean drinking water per day, depending on the efficiency of the system.
Theoretical analysis of water distillation using solar still. An experimental performance based on stepped solar still coupled with solar air heater was investigated by. Solar still,a water purifying technique project report. The solar still is one of the oldest and by far the simplest water desalination method. With just a few basic building materials, a sheet of glass. Solar water distillation safe drinking water foundation. The force of attraction to the earth of the hot fluid is less than for the cold fluid. The effect of a vertical flat plate reflector on the distillate productivity of a basin type solar still and a tiltedwick solar still has been evaluated by tanaka and nakatake 46.
Rain water harvesting on the top cover of the solar still would produce about 40 m3 of water a year. Analytical simulation of energy behavior of solar stills and. The principle of operation of these devices is evaporation and condensation. Pdf the performance of active single slope solar still using different.
Solar stills distill water using the two main scientific principles of the water cycle evaporation and condensation. The heat losses as well as the experimental and thermal efficiencies of the stills were. The distillate productivity, solar intensity, and the temperatures of the basin water, glass cover and the ambient of the three stills were measured and their relationships were investigated. The updated suns river solar still operated with nighttime recovery of distillate from heated cooling water resulting in regeneration of the next days cooling water is a process which can serve water needs for a family or a group of families. Aug 26, 20 solar still,a water purifying technique project report 1. Pdf theoretical analysis of solar distillation using active solar still. Solar stills are systems of easy operation and low cost that, through the use of energy supplied by the sun, rise the water temperature for a sufficient period of time in equipped containers to achieve the absorption of heat from radiation 1. Simulation of solar still processes of salt water tecnico lisboa. A solar still is a potential direct solar desalination system that exposes a shallow water basin inside a fully closed container to solar radiation in order to evaporate water. Dec 08, 2016 solar stills can be used for low capacity and selfreliant water supplying systems.
The solar still can be effectively used to obtain sufficient quantities of good water from salt water in regions where the insulation of solar energy is high. The principle of operation is the greenhouse effect provided with the glass cover. It was found that 1 cm depth gives the best performance in terms of fresh. Calculated solar fraction 97% inclination azimuth 15 30 45 60 75 90. A solar still distills water with substances dissolved in it by using the heat of the sun to evaporate water so that it may be cooled and collected, thereby purifying it. Basin water depth is one of the design and operating parameters that determines the performance of solar still. Maximum efficiency of the still with the wick surface is found as 42% while the efficiency of the conventional solar still is 33%. Desalination using solar energy is suitable for potable water. Solar collectors solar collectors are the key component of active solar heating systems. A solar still consists of a structural element called a basin covered with a transparent material to allow the incident solar radiation to pass through to the basin saline water for thermal absorption and evaporation.
Theoretical and experimental investigations on solar. The aim and main objective of the project is to build a costefficient solar water heater swh for the purpose of using it in the model house that was chosen randomly for renovation, which itself will be as a motivation for the villagers to consider doing such renovation for their houses. For smallscale fresh water production, basin type solar stills are viable options. Typical efficiencies for single basin solar stills approach 60 percent. Solar water pumping principles for any solar pumping system, the capacity to pump water is a function of three main variables pressure, flow, and power to the pump.
Water purification using solar still withwithout nano. Table 3c linear characteristic equations for a single slope passive solar still at 30 angle of inclination of condensing cover at different brine water depths for the month of june, 2004 sr. A mathematical model was developed using the above set of equations, and was used to predict the glass temperature, water temperature. For purposes of designing a solar pumping system, pressure can be thought of as the work that the pump must overcome to move a certain amount of water. Performance improvement of a passive solar still in a. Sep 17, 2012 make your own distilled water from stream or lake water, salt water, or even brackish, dirty water, using these diy solar still plans. The solar still cover traps solar energy within the enclosure, which heats then the saline water. Survival metrics the solar still deluxe water purification kit. Experimental evaluation of a single slope solar still. Modification and operation of a full solar distillation. Solar still efficiency n is the amount of energy utilized in vaporizing water in the still over the amount of incident solar energy on the still q t in jm2 day.
May 22, 2014 solar still technologies bring immediate benefits to users by alleviating health problems associated with water borne diseases. Passive solar still using a regenerative system the regenerative system consists on a flow of water, which runs over the cover of the solar still, aiming for the reduction of the temperature of the same. A thesis submitted to the faculty of the graduate school. Evaluation of the implementation of the solar still. The only disadvantage is the large amount of space needed. The radiation from the sun evaporates water inside the solar still at a. The sun evaporates dirty water which is then cooled and collected in pure form. Solar water distillers or solar stills are usually used in remote areas where there is limited access to freshwater. A number of variables have been considered including the water depth inside the still and the inlet saline water temperature to the solar still heater solar collector system.
The goal of my design is to be efficient and to maintain a good water temperature of between 50 c and 65 c or more throughout the year. Pdf solar powered water pumping system yuvraj siddharth. Water purification using solar still withwithout nanofluid. The radiation from the sun evaporates water inside the solar still at a temperature higher than the ambient. Characterization of water quality before and after distillation in the solar still showed a reduction in chemical. The dirty water is left to sit in the sun, allowing it to absorb solar. The characteristic equation has been used for experimental results of a passive solar still to generate linear and nonlinear characteristic equations for winter and summer conditions. A broad classification of the solar stills is depicted above. Design, fabrication and performance evaluation of solar. Comparative cost of compact nature of solar stills like single slope, double slope and wick type solar still was more than rs. Experimental investigation on pyramid solar still with single and. The experimental tests were conducted for five months in the city of kirkuk, north of iraq, at 43. A solar still is an artificial water purifier that imitates the natural mechanism used by nature to purify water. For solar stills users, there is a also a sense of satisfaction in having their own trusted and easy to use water treatment plant onsite.
A square foot of still area can produce approximately 12 to 34 lb of distilled water per day. Single slope solar stills can be used, for water desalination and distillation. Optimization the performance of single basin solar still with. Current designs for solar coproduction of water and electricity are considered. Aybar 2007 defined a solar still as a simple device to desalinate impure water like brackish or saline water to get potable fresh distilled water, using solar energy as a fuel, for various. Pdf theoretical analysis of water distillation using solar still. A project report on solar still submitted in partial fulfillment for the award of the degree of bachelor of technology in mechanical engineering from rajasthan technical university, kota session 2012 guided by. Characteristic equation of a passive solar still sciencedirect. The tds total dissolved solids in the pure water is 81 ppm.
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