Karl-Heinz Funken

Application of concentrated solar radiation to high temperature detoxification and recycling processes of hazardous wastes

Abstract In many cases, hazardous wastes are subject to thermal treatment at elevated temperatures. Some types of wastes do not have a sufficient calorific value to cover the heat demand of the high temperature process. For thermal treatment of e.g. filter residues, dusts, sulfuric acid, aluminium dross, foundry sand, or waste water, supplementary energy supply is needed. The specific energy demand ranges from 0.5 to 2.5 kWh/kg (2–10 MJ/kg). An important aim of process optimisation is the reduction of (fossil) energy consumption and exhaust gas flow. Concentrated solar energy promises advantages when applied to high energy consuming waste treatment processes with regard to substitute fossil or electric energy consumption, to reduce CO2 emissions, and exhaust gas flow. In parallel to conceptional studies, a solar-heated rotary kiln mini-plant has been designed and constructed for tests in the DLR solar furnace. The tests will give indications of boundary conditions for solar thermal treatment or conversion of selected hazardous materials.

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

The energy demand of photochemical synthesis of e-caprolactam was compared for two plant concepts. The conventional lamp-driven concept followed the process as realized on an industrial scale by Toray Ltd, Japan and a solar concept was designed at identical yearly output. The aim of the comparison was to determine the savings of fossil fuels that could be achieved if photochemistry could make use of solar radiation instead of artificial light. The use of solar radiation for the photochemical production of e-caprolactam has a 4-fold lower demand for electric current and an 8-fold lower demand for cooling energy as compared to an equivalent conventionally operated route. Furthermore, due to avoided conversion of fossil fuel to electric current, a solar process would allow specific emissions of 1.5–2.5tons of CO2 per ton e-caprolactam to be avoided, depending on the primary energy carrier used.

Technologies for the solar photochemical and photocatalytic manufacture of specialities and commodities: A review.

Solar radiation and solar technology substitute for electricity, cooling energy and expensive equipment that are required for the conventional lamp-operated photochemical techniques. The maturity of the techniques would allow commercial-scale applications. In the meantime numerous reaction classes have been proved to be feasible for synthetic solar photochemical technology, including photooximations, sensitized photoisomerizations, photooxygenations and photocycloadditions, photorearrangements, photoinduced alkylations, and catalyzed heterocyclizations and photooxidations. A wide variety of valuable products could be manufactured that way.

Solar chemical engineering and solar materials research into the 21st century

“Solar Chemistry and Solar Materials Research” is one important task of the “Solar Energy Association North Rhine–Westphalia, Germany”. Numerous individual projects have been carried out which address the construction and operation of a high-flux solar furnace, solar chemical engineering, and solar materials research. Almost 10 years of research and development have led to significant progress. This paper reviews the scope of work in solar chemistry and summarizes the results. The authors present perspectives for commercialization and address open questions and needs for further research and development.

SynLight – the world’s largest artificial sun

High-flux solar simulators, providing predictable and reproducible solar radiation, have emerged to indispensable tools for efficient development of CSP components or solar chemical processes. In the last decade, a number of such facilities have been erected, however significantly below the typical scale of pilot plants.DLR started the construction of a large solar simulator in Julich near its solar power tower. The facilities’ modular design is novel and characterized by 149 individually controllable 7kW Xenon short-arc lamps. Solar radiant powers of up to 280kW and 2 x 220kW are expected to be available in three separately useable radiation chambers. In 2017, the large artificial sun shall be available for the global CSP and solar chemical community within cooperative research projects.

Engineering and erection of a 300kW high-flux solar simulator

German Aerospace Center (DLR) is currently constructing a new high-flux solar simulator synlight which shall be commissioned in late 2016. The new facility will provide three separately operated experimental spaces with expected radiant powers of about 300kW / 240kW / 240kW respectively.synlight was presented to the public for the first time at SolarPACES 2015 [1]. Its engineering and erection is running according to plan. The current presentation reports about the engineering and the ongoing erection of the novel facility, and gives an outlook on its new level of possibilities for solar testing and qualification.