Design, Development and Experimental Results of a Solar Distillation System for the Processing of Medicinal and Aromatic Plants
Abstract
With the increasing population and industrialization, there is need to cut down the load of fossil fuels and to reduce environmental pollution. Solar energy investments in developing countries are imperative to avoid an energy crisis arising from over-dependence on fossil fuels. The situation is critical because fossil fuels are finite and fast depleting (Okoro, 2004). From a number of studies on industrial heat demand, several industrial sectors have been identified with favorable conditions for the application of solar energy. The most important applications of solar energy using heat are: sterilizing, extraction, pasteurizing, drying, solar cooling and air conditioning, hydrolyzing, distillation and evaporation, washing and cleaning, and polymerization. The ranges of all these processes lie between 60-280 oC (Kalogirou, 2003). Most of the agro-based industries can be operated in this medium temperature range. The use of solar energy in agriculture sector can be used to process many perishable agricultural products at farm level. At present, various kinds of solar collectors are in use in the sector of agriculture and post harvest technology, yet their applications are restricted only to drying and warming water etc. Beyond this low temperature applications there are several potential fields of application of solar thermal energy at a medium and medium-high temperature level. In particular, an important research effort has been directed towards power generation applications, chemical systems, and process heat (Estrada, 2007). Tremendous efforts have been made in areas of application of solar energy in the agricultural sector. This can be seen in areas of solar water heating for dairy and micro irrigation (Oparaku 1991; Jenkins 1995; Essandu-Yeddu 1993). The promotion of small scale agro-based industries by using innovative solar collectors can open new landmarks in rural development especially in tropical countries.