A Spanish research group from a public university has developed a solar dryer using air or another gas under pressure for drying industrial products and food products of any type.
Among the main highlights of this technology are its higher solar collection output and its autonomy to work without other external energy supply than solar collection.
This new solar dryer uses a gas (preferably air) under pressure, comprising two areas, a high-pressure area and a low-pressure area. The high-pressure area must be leak-tight. Furthermore, if air is used, the possible leaks will not present any environmental issues. This increase in pressure makes evaporation somewhat difficult, but solar collection output is in turn improved, so a smaller solar collection surface area is required.
In addition, when the drying space is located in the high-pressure area, access to the materials requires certain guidelines to conserve said pressure, and if it is located in the low-pressure area, the operator can more readily access such materials.
Finally, the gas circulation system can be set up as an open circuit or as a closed circuit, where a closed circuit is particularly indicated when a gas other than air is used.
Nowadays, solar dryers are used in many industrial sectors, such as, chemical, pharmaceutical and food industry. The developed solar dryer has significant improvements comparing to the current solutions. It’s main features are:
• A higher solar collection output, and therefore a smaller solar collection surface area is required.
• It can work without any external energy supply (except from solar collection), although there should be some as supporting energy in non-optimal situations.
• If the system receives sufficient solar collection and pressure losses are moderate, no other external energy supply is required.
• Able to work as an open circuit or as a closed circuit
The researchers are looking for undertakings that produce chemicals, powder or granular materials, construction materials or handcrafted items for financial and license agreement. They are willing to build and design the prototype for further testing, validation and industrial development.