Solar collectors versus lamps - a comparison of the energy demand of industrial photochemical processes as exemplified by the production of epsilon-caprolactam

The energy demand of photochemical synthesis of E-caprolactam was compared for two plant concepts. The conventional lamp-driven concept followed the p rocess as realized on an industrial scale by Toray Ltd, Japan and a solar c oncept was designed at identical yearly output. The aim of the comparison w as to determine the savings of fossil fuels that could be achieved if photo chemistry could make use of solar-radiation instead of artificial light. Th e use of solar radiation for the photochemical production of is an element of-caprolacram has a 4-fold lower demand for electric current and an 8-fold lower demand for cooling energy as compared to an equivalent conventionall y operated route. Furthermore, due to avoided conversion of fossil fuel to electric current, a solar process would allow specific emissions of 1.5-2.5 tons of CO2 per ton is an element of-caprolactam to be avoided, depending on the primary energy carrier used. (C) 1999 Elsevier Science Ltd. All righ ts reserved.