Experimental study of solar water distillation system with thermosyphon heat pipe exchanger for arid areas of balochistan

Project Title

Experimental study of solar water distillation system with thermosyphon heat pipe exchanger for arid areas of balochistan

Project Area of Specialization Mechanical EngineeringProject Summary

More than 97 % of water available on earth’s surface is either salty or polluted with contaminants harmful for human beings. The availability of fresh potable water is an important issue for developing countries like Pakistan, especially in the remote and arid regions like Khuzdar city of Balochistan province. Several different methods are used for the purification of water such as, reverse osmosis (RO), UV and UF filtration, desalination, clay vessel filtration, and water distillation etc. However, these methods are costly and consume large amount of electricity, which is another major issue for the remote areas. The solar water distillation is an environment friendly method for the purification of water. This method utilizes solar thermal energy to evaporate the water from solar still, which is then collected through condensate channel in the liquid form, leaving behind the dissolved salts and dirt sediments. This environment friendly method is highly suitable for the regions like Khuzdar, which has one of the highest annual mean solar irradiance (5.9-6.2 kWh/m²/day with an average sunshine duration of 8-8.5 hours a day).

The conventional solar water distillation system has the low distillation rate per unit area (3–4 L/day m²). To increase the distilled water production rate, it is required to raise the temperature difference between the solar still and condensate plate. In this project, we will design and investigate the output of a low cost solar water still combined with thermosyphon solar water heater to raise the temperature of contaminated water and provide the preheated water to the solar still. The water will then absorb more heat from the solar still. This will increase the evaporation rate due to high absorbent area. Additionally, the absorption and insulation of solar still will be improved by surface modification of absorber and porous insulation foam to improve solar radiation absorption and reduce heat loss to the surroundings. The main objective of this project is to build a cost effective portable solar water still with high distillation rate suitable for the remote and arid areas of Khuzdar.

Project Objectives

The most important issue faced by developing countries is extended shortage of pure drinkable water.  The prolonged use of contaminated water sources for drinking and cooking purposes can cause serious health problems and chronic diseases. A portable solar water still can produce pure drinkable water for a household through distillation process. It is the cheapest process in terms of cost and power among the processes used for water purification. It is especially recommended for arid and semiarid areas where drinking water shortage is a major problem and solar radiation is high.

1. This study aims to optimize the distilled water production rate of a conventional solar still by combining thermoshyphon solar water heater to increase the evaporation rate.
2. The main objective of this experimental work is to build a cost effective and portable solar water still with high distillation rate.

Project Implementation Method

Methodology

1. Literature review

• Preliminary research on existing studies on the topic from journals and books.
• Understand the concept of solar stills water production, absorption, condensation, evaporation and water treatment.

2. Experiment

• Prepare the equipment and materials needed prior to experiment.

3. Data collection

• Conduct the experiment and collect the data
• Analyze the data and prepare the discussion.

4. Conclusion

• Conclude the experiment
• Prepare the final report.

Benefits of the Project

The conventional solar water distillation system has the low distillation rate per unit area (3–4 L/day m²). To increase the distilled water production rate, it is required to raise the temperature difference between the solar still and condensate plate. A thermosyphon solar water heater combined with the solar still can be used to raise the temperature of contaminated water and provide the preheated water to the solar still. The water will then absorb more heat from the solar still. This will increase the evaporation rate due to high absorbent area. Additionally, the absorption and insulation of solar still will be improved by surface modification of absorber and porous insulation foam to improve solar radiation absorption and reduce heat loss to the surroundings. The main objective of this project is to build a low cost portable solar water still with high distillation rate suitable for the remote and arid areas of Khuzdar.

Technical Details of Final Deliverable Technical details of cost effective solar water distillation system combined with solar thermosyphon heat exchanger

Materials for experimental setup:

Solar still tank:

1. 100 by 120 cm2 wooden frame for solar still
2. Aluminum sheet and carbon black coated paper for solar absorber
3. Transparent acrylic sheet for top and side walls
4. PVC condensate channel
5. Polystyrene foam for bottom and walls insulation

Figure: Schematic of solar still  (All measurements in cm)

Solar thermal heat exchanger:

1. Copper tubing
2. Carbon black coated paper for absorber
3. Flat top glass/ transparent acrylic sheet

Figure: Schematic of thermosyphon combined with solar still

Data Collection:

1. Measurement of total dissolved salts (TDS) of water samples from a laboratory before distillation
2. Solar radiation data of Khuzdar from metrological department or from the literature
3. Temperature sensors data at inlet, outlet and ambient temperatures of thermosyphon heat exchanger
4. Calculation of solar thermal efficiency and distilled water production rate in liters per day per square meter
5. Measurement of TDS of water after distillation

Results and conclusion:

1. Analyze the results and prepare the discussiom
2. Report writing

Final Deliverable of the Project Hardware SystemCore Industry Energy Other Industries Education , Food , Health Core Technology Clean TechOther TechnologiesSustainable Development Goals Clean Water and SanitationRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	61383
Wooden frame	Equipment	2	2000	4000
Aluminum sheet	Equipment	4	400	1600
Carbon black paper	Equipment	4	500	2000
Acrylic sheets	Equipment	4	1500	6000
PVC pipes	Equipment	6	200	1200
Polystyrene foam	Equipment	2	1500	3000
Copper tubes	Equipment	2	3700	7400
Temperature sensors	Equipment	6	275	1650
Digital smart sensor device for temperature and humidity	Equipment	1	13000	13000
A4 papers	Miscellaneous	1	895	895
Printing	Miscellaneous	500	10	5000
Traveling between Khuzdar and Karachi	Miscellaneous	2	2000	4000
TDS Meter 6032EZDO	Equipment	1	6400	6400
Water storage can	Equipment	2	899	1798
Silicone sealant 310 ml	Equipment	4	360	1440
Steel frame for support	Equipment	1	2000	2000