Essay on Solar Dryer

Introduction

Solar dryers are specific devices that involve in the usage of solar energy for drying the substances, specifically food. There is availability of two kinds of solar dryers that includes direct and indirect. Solar dryers that are direct are specific dryers that involve in exposing the substance in dehydration to direct sunlight. According to history, clothing and food are considered to be dried under the sun through the usage of lines, and laying the certain items over the rocks, as well as top of tents. In indirect solar dryers, the black surface is considered to be heating the incoming air instead of the direct heating of the substance that need to be dried. One specific modern kind of solar dryer is in possession of a certain black absorbing surface involved in the collection of the light, and converting it to heat. The substance seems to be placed directly over the surface. The specific driers are in possession of enclosures, cover of glass and vents fr the increase of the efficiency (Güler et.al., 2020).

As per the indirect solar dryers, the specific heated air is considered to be passed over the specific substance that needs to be dried, along with the exits upwards usually through a certain chimney, taking the moisture released from that specific substance with it. They can be quite simple, just a tilted cold frame within the black cloth to be under insulation of brick building with the ventilation that is active, along with a heating system for back-up. One of the benefits of the indirect system is that it is considered to be quite easier in terms of the protection of the food and other substances from contamination. The direct sun too seems to be having the ability of chemically altering the foods making them quite less appetizing.

Solar Drying

The solar drying is considered to be a heat with complexities, and is a process of mass transfers. As the specific procedure is involved with drying, and the dehydration of the materials through the means of solar energy, in which the moisture must be removed from the interior of the material to a certain surface, and then for removing the form of the moisture of the surface material as well. Drying products of agriculture through solar energy is considered to be among the traditional methods. The specific procedure is considered to be helping in the removal from the products of agriculture, along with providing help by preserving them (Lingayat et.al., 2017). The traditional solar drying seems to be done over an open ground, and thus, there is no control over the rate of the drying in terms of the products leading to uniform drying as well. Sometimes farmers are also used for leaving it for longer period of drying due to the slow drying leading to deterioration of the products of agriculture by forming the fungus and the bacteria through moisturization.

The solar radiation seems to be used for drying being among the oldest applications in terms of solar energy. It was under usage since the mankind dawn for the preservation of the food; however also in order to dry other important materials such as materials of construction, cloths, etc. The first installation in order to dry stuff through solar energy was found in Southern part of France and is considered to be dated at around 8000 BC. Solar heat was the only availability of the only source of energy to the mankind until the discovery, along with the usage of both woods and biomass. Till date within remote smaller communities, along with the so-called regions of the third world and the western nations, the people seem to be taking benefit of solar radiation for drying and preserving the smaller amounts of food.

Solar drying has not been under broader commercialization. Solar dryers are considered to be equipment, generally in terms of smaller amounts of capacity and based instead of empirical as well as semi-empirical data instead of the theoretical designs. The majority in terms of the several designs of solar dryers that are in availability are used significantly for drying the different crops both for family usage, and both for the small-scale industrial production. A quite short description from history states that there was usage of solar drying through numerous centuries. Some of the drying phenomena, independently in terms of the energy usage, along with the general laws helping in the governance of the drying methodologies through convection of short analysis for the researchers to be following with easily following the details in terms of the procedure solar drying (Sözen et.al., 2020). Specific collectors of the solar dryers have been using drying and methods to couple to the numerous solar dryers as per description as an indirect source of the solar thermal energy.

Over the evolution of the mankind, there have been inventions of numerous technologies in order to dry the products of the agriculture inclusive of drying through superheated steam, drying through spray, heat pump, vacuum, and much more. In all the specified systems, there can be certain control over the process of drying; however, the systems are operated through fuels such as natural gas, coal and oil. The specific fuel used in operating the dryers is certainly not eco-friendly. For balancing the rate of drying, along with the method that is eco-friendly in terms of drying, the solar energy seems to be acting as the most favored alternative since it is the specified source of renewable energy; there is availability of free cost and the eco-friendly seems to be in every single way.

The usage of the solar energy in the current era, has been reaching an incredible edge. The constant research for an alternative source of power is due to the perceived scarcity in terms of the fossil fuels within the force that is driving. It had been under massive popularity with the continuity in the rise of the cost of the fossil fuel (Güler et.al., 2020). Out of all the renewable source of energy that are in availability, the solar energy is considered to be the most abundant and is under availability in both the direct forms, and the indirect forms as well. The applications of solar energy seem to be categorized significantly in two major categories. The first one seems to be in a direct conversion with the electricity through the usage o solar cells, and the second one is the thermal application. The second is considered to be inclusive of the heating through solar energy, cooling through solar energy, solar drying, solar cooking, distillation through solar energy, air heating, water heating, and thermal power generation, all through solar energy.

Conclusion

According to history, clothing and food are considered to be dried under the sun through the usage of lines, and laying the certain items over the rocks, as well as top of tents. In indirect solar dryers, the black surface is considered to be heating the incoming air instead of the direct heating of the substance that need to be dried. The specific procedure is considered to be helping in the removal from the products of agriculture, along with providing help by preserving them. The traditional solar drying seems to be done over an open ground, and thus, there is no control over the rate of the drying in terms of the products leading to uniform drying as well. Sometimes farmers are also used for leaving it for longer period of drying due to the slow drying leading to deterioration of the products of agriculture by forming the fungus and the bacteria through moisturization. The majority in terms of the several designs of solar dryers that are in availability are used significantly for drying the different crops both for family usage, and both for the small-scale industrial production.

A quite short description from history states that there was usage of solar drying through numerous centuries. Some of the drying phenomena, independently in terms of the energy usage, along with the general laws helping in the governance of the drying methodologies through convection of short analysis for the researchers to be following with easily following the details in terms of the procedure solar drying. One specific modern kind of solar dryer is in possession of a certain black absorbing surface involved in the collection of the light, and converting it to heat. The substance seems to be placed directly over the surface. The specific driers are in possession of enclosures, cover of glass and vents for the increase of the efficiency.

Reference

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