On-farm processing of medicinal and aromatic plants by solar distillation system

Essential oils have been used throughout the world in foods, fragrances, perfumery, cosmetics, and medicines and these oils are very expensive. The study was initiated to develop an on-farm solar distillation system for functional, environmental and economic reasons. A Scheffler fixed focus concentrator is used for the solar distillation system. The system comprises a primary reflector (8 m2 area), secondary reflector, distillation still, condenser and Florentine flasks. The primary reflector rotates along an axis parallel to the earth’s axis of rotation with the help of a precise photovoltaic tracking device and keeps the reflected beam aligned with the fixed secondary reflector as the sun moves. The secondary reflector further reflects the beam to target the bottom of the distillation still. The paper presents the development, evaluation and experimental results of the solar distillation system. The temperature at the focus was recorded as between 300 and 400 °C for beam radiation in the range 700–800 W m−2. The average power and efficiency of the solar distillation system were found to be 1.548 kW and 33.21% respectively. Different medicinal and aromatic plants like Melissa, Peppermint, Rosemary, Cumin, and Cloves etc were processed successfully by using the solar distillation system and their process curves were drawn.