Drying is one of the most popular but energy-intensive technological operations. High costs of energy resources inevitably affect the cost price of commercial production, competitiveness and the impact of its production technology on the environment. An inexhaustible, cheap and environmentally friendly source of energy is the Sun. Currently, devices using solar radiation are increasingly being installed in practice.
A unique dryer using the energy of solar radiation has been installed in the Medicinal Plant Farm of the Full House Community in the village of Panara. It consists of a dryer preparation-supply system, drying capacity, and process management equipment which is used to record and control environmental conditions and dryer parameters, to control ventilation intensity and dryer flows, and to perform accounting of dried raw materials. There are two types of drying containers for drying vegetable raw materials: ventilated ovens and shelf drying cabinets. Therefore, conditions have been created for drying both large-stemmed plants and smaller fractions or chopped plant material (flowers, petals, buds, mushrooms, fruits, etc. of medicinal/spice plants). The principle of active ventilation is used for ventilation of the raw material to be dried. The dryer preparation-supply system consists of fans, a damper system to control the dryer flows, an aerial solar collector and additional heating equipment to control the temperature of the dryer. The aerial solar collector is integrated into the roof structure of the building, the southern slope of the roof. Its total area is 131 m2. The energy of solar radiation absorbed in the collector is used to heat the ambient air sucked in for drying. The air flow that has passed through the solar collector and has warmed up flows into the ventilator inside the building and is further directed to the drying tanks. The collector uses direct sunlight and does not accumulate heat, so its heating power varies depending on the year and time of day, cloudiness and passing air flow. Therefore, to control the temperature of the dryer, the dryer preparation-supply system is additionally equipped with heaters, which allows heating the dryer using other heat sources, such as a heat pump, solid fuel or photovoltaic energy. The damper system installed in the dryer is also designed to control the temperature of the dryer and save heat. Dryer and drying technology are intended for drying and processing of plants accumulating biologically active substances: medicinal/spice plants, vegetables and fruits, that are characterized by high initial humidity and sensitivity to unfavorable drying conditions. In most cases, long-term ventilation with an intense flow of heated air is inevitable, and at the same time it requires high energy costs. The developed and implemented solar radiation energy-using drying technology allows to reduce the energy requirements for the drying process and prepare high-quality vegetable raw material.
Effect: Agro-environmental protection, Economical, Sustainable Farming
Argumentation: The developed and installed drying technology using the energy of solar radiation allows to reduce energy requirements for one of the most expensive and popular technological processes - drying. In addition, the drying technology and dryer temperature and flow control system are adapted to plants accumulating biologically active substances: medicinal/spice plants, vegetables and fruits, dried and prepared for high-quality and high-added-value plant raw materials.
Project description: First stage: "Herb farm in Panara as an example of environmentally friendly farming in Dzūkija National Park" (2005-2007) Second stage: "Dissemination of promising medicinal plant cultivation and innovative technologies for preparation of medicinal plant raw materials using solar energy" (2011-2014)
Technology of drying plant-based products.pdf
