Performance of a solar energy powered falling film evaporator with film promoter

• Published in: Energy conversion and management 2008-12, Vol.49 (12), p.3550-3559
• Main Authors: Souza, T.R., Salvagnini, W.M., Camacho, J.L.P., Taqueda, M.E.S.
• Format: Article
• Language: English
• Subjects: Air pollution control; Applied sciences; Crude oil, natural gas and petroleum products; Devices using thermal energy; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Falling film evaporation; Film promoter; Fuels; Furnaces; Natural energy; Petroleum products, gas and fuels. Motor fuels, lubricants and asphalts; Solar collectors; Solar concentration; Solar energy; Solar evaporation; Solar thermal conversion; Structured surface
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2008.08.001

A solar energy powered falling film evaporator with film promoter was developed for concentrating diluted solutions (industrial effluents). The procedure proposed here does not emit CO 2, making it a viable alternative to the method of concentrating solutions that uses vapor as a heat source and releases CO 2 from burning fuel oil in a furnace, in direct opposition to the carbon reduction agreement established by the Kyoto protocol. This novel device consists of the following components: a flat plate solar collector with adjustable inclination, a film promoter (adhering to the collector), a liquid distributor, a concentrate collector, and accessories. The evaporation rate of the device was found to be affected both by the inclination of the collector and by the feed flow. The meteorological variables cannot be controlled, but were monitored constantly to ascertain the behavior of the equipment in response to the variations occurring throughout the day. Higher efficiencies were attained when the inclination of the collector was adjusted monthly, showing up to 36.4% higher values than when the collector remained in a fixed position.