نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانش آموخته دانشگاه شهید چمران اهواز

2 استادیار گروه مهندسی بیوسیسیتم دانشگاه شهید چمران اهواز

چکیده

تهیه و تامین آب آشامیدنی سالم و پایدار در هر جامعه‌ای یکی از مهمترین و با اهمیت‌ترین کارها در جهت ارتقاء سلامت جامعه است. بر همین اساس پژوهشگران همواره به دنبال روش‌های نوین جهت تولید آب شیرین و گوارا هستند. یکی از روش‌های نوین تولید آب شیرین در حجم پایین استفاده از سامانه‌هایی است که به روش چگالشی از رطوبت هوا تولید آب می کنند. در این پژوهش نیز از رطوبت هوا به عنوان یک منبع جبران شدنی، برای تولید آب استفاده شد و اثر عوامل دما (در چهار سطوح 20، 30، 40 و50 درجه سانتی گراد)، رطوبت هوا (در چهار سطوح 30، 50، 70 و 90 درصد)، دبی هوای ورودی (در سه سطح 5/2، 5 و 5/7 متر مکعب بر ساعت) و طول موثر لوله (در دو سطح 2 و 4 متر با قطر 30 میلی متر و ضخامت 1 میلی متر) بر میزان تولید آب مورد بررسی و تحلیل قرار گرفت. طرح آماری مورد استفاده، طرح کرت‌های خرد شده در قالب بلوک های کاملا تصادفی بود و تجزیه و تحلیل داده‌ها و مقایسه میانگین‌ها با استفاده از نرم افزار SPSS انجام پذیرفت. نتایج نشان داد که هر یک از عوامل رابطه مستقیم با میزان تولید آب دارد و بیشترین میزان تولید آب در شرایط دمای 50 درجه سانتی‌گراد، سرعت 3 متر بر ثانیه، رطوبت 90 درصد و طول لوله مسی 4 متر در بازه زمانی معین بدست آمد.

کلیدواژه‌ها

عنوان مقاله [English]

Investigation of effective factors on water production system using land cooling

نویسندگان [English]

  • shayan hajinajaf 1
  • shaban ghavami jolandan 2
  • Hassan Masoudi 2

1 Master of Science, Department of Biosystems Engineering, Faculty of Agriculture, Shahid Chamran University of Ahvaz

2 Assistant professor, Department of Biosystems Engineering, Faculty of Agriculture, Shahid Chamran University of Ahvaz,

چکیده [English]

Investigation of effective factors on water production system using land cooling

Abstract

Introduction Water scarcity has been a worrying issue and one of the obstacles to economic growth of countries, despite various water supply sources such as groundwater, seas, rivers and rainfall. Today, in many parts of the world, due to the scarcity of water resources, disputes over access to water resources have crossed national borders and access to these resources has become a strategic goal in the interaction between countries. According to statistics released by the World Resources Institute in recent years, about 35 countries will face water stress in 2040, of which Iran ranks 13th. Considering the average rainfall in Iran and also considering the amount of water resources and per capita consumption in the country, Iran is considered among the countries that are at risk of lack of physical water resources. The purpose of this study was to provide safe water for domestic use and drinking water without using fresh water sources and only with the benefit of the air humidity. In fact, the goal is to provide fresh water from the humidity, especially for remote areas and villages with small populations that do not have access to water. In this method, there is no need to use fossil and electrical energy and only wind energy, air humidity and depth of the earth are the factors of its production, and so it is also economically viable. The system considered in this research reduces the air temperature and cools it until the saturation phase by blowing the outside hot air into a buried pipe underground. In this way, some part of the air moisture is separated and appeared in the form of water droplets on the pipe wall; then the obtained water is stored in a tank and used.
Materials and Methods In this research, a system was used that was partly underground and partly out of the soil. Buried sections include the copper pipes, the circuit breakers and connections, and a water tank and the sections on the ground include a cubic chamber with dimensions of 2×2 m, temperature and humidity sensors, fans, inlet air supply section, valves control levers, air conditioners, heaters and humidifiers. During the tests, the temperature and humidity inside the chamber were controlled by a microcontroller board and the effect of changes in air humidity (30, 50, 70 and 90%), air temperature (20, 30, 40 and 50 °C), inlet air flow (2.5, 5 and 7.5 m3/h , equal to the speeds of 1, 2 and 3 m/s , respectively) and the pipe effective length (2 and 4 m with a fixed diameter of 30 mm and a thickness of 1 mm) on the amount of extracted water was evaluated. The burial depth of the pipe was about 1 m and the soil temperature was measured by a sensor next to the buried pipes. The used statistical design was the split plots design in the form of completely randomized blocks and the results were analyzed and compared using SPSS software. In order to create and control different atmospheric conditions inside the chamber, it was necessary to consume electrical energy, while in the open space water can be produced from this system without the need for electrical energy.
Results and Discussion the studied factors, including the pipe length, air humidity, air temperature and air flow rate (inside the pipe), affected on the amount of produced water significantly. By increasing of the air humidity, the air flow rate, the chamber air temperature and the pipe length, the amount of produced water was increased. The air temperature of 50 °C, the air velocity in 3 m/s, the humidity of 90% and 4 m length of the copper pipe had the maximum water production in a certain period of time.
Conclusion The results of the present study show that water production from air humidity can be used as a method to produce fresh water, especially in remote and low populated areas with high air humidity that do not have access to the fresh water. Although the volume of water production by this method is not comparable with methods such as the multi-stage distillation, but it is economical and does not require any energy.

کلیدواژه‌ها [English]

  • Water production
  • Condensation
  • Air humidity
  • Earth cooling
  • Environmental parameters
  1. Alamdari, F.A., 2009. Examining the types of common desalination plants and designing a sample of solar desalination plants. Bachelor Thesis, Faculty of Mechanical Engineering, Khajeh Nasir al-Din Tusi University of Technology, Tehran.
  2. Bazargun, M., and Ahmadi, A.B.M. 2014. Production of Fresh Water Using Underground Cooling of Humid Air and Solar Energy. Khajeh Nasir al-Din Tusi University of Technology, Tehran.
  3. Baziyar,M.A., and Irajpour, A.A. 2016. Development of thermoelectric elements in the design and construction of fresh water extraction devices from air humidity. 3rd International Conference on New Research Achievements in Civil Engineering, Architecture and Urban Management, International Confederation of World Inventors.
  4. Dastani, Z. 2016. Agriculture is a nation’s water killer. Ebtekar newspaper, NO 3457, 20 June 2016.  (In Persian)
  5. Janzadeh, A.H. 2018. Water extraction from air using depth of earth temperature (Case study: system efficiency study in Bandar Abbas), Journal of Water and Soil Conservation Research. Volume 25, Number 2, Gorgan University of Agricultural Sciences and Natural Resources.
  6. Joshi, V.P., Joshi, H.A., Kothari, M.D., Mahajan, M.B., and Chaudhari, K.D. 2017. Experimental Investigations on a Portable Fresh Water Generator Using a Thermoelectric Cooler. Energy Procedia, 109: p. 161-166.
  7. Lindblom, J., and Nordell, B. 2007. Underground condensation of humid air for drinking water production and subsurface irrigation, Desalination 203, 417–434.
  8. Mahmoudi, P., Khajehamiri, C., and Salari, M. 2016. Feasibility study of water extraction from air humidity in the south of Sistan and Baluchestan province. Journal of Soil and Water Conservation Research, Volume 23, Number 2.
  9. Mohammadi, A. 2012. Production of fresh water from humid air with underground cooling system. Master Thesis, Faculty of Mechanical Engineering, Khajeh Nasir al-Din Tusi University of Technology, Tehran.
  10. Mohamed M.H., William G.E., Fatouh M. Solar energy utilization in water production from humid air. Sol Energy 2017; 148: 98–109.
  11. Nerlekar, S. P. 2017. Atmospheric Water Generator: Air Drops. International Journal of Advanced Research Trends in Engineering and Technology (IJARTET) Vol. 4, Special Issue 2.
  12. Rahimi, M., Rad, B.R., and Mohammadian, N. 2010. Coastal water resources management and theoretical feasibility of water extraction from fog. The first national conference on coastal land water resources management.
  13. Rosegrant, M.W. X. Cai and S.A. Cline. 2002. World Water and Food to 2025: Dealing with Scarcity, International Food Policy Research Institute.
  14. Zaretabar, M., and gorji, M. 2017. Laboratory study of water humidity generating device based on thermoelectric cooler. Fourth National Conference on Recent Achievements in Civil Engineering, Architecture and Urban Planning, Tehran.