Dr. Volker Hoenig

Volker Hoenig studied mechanical engineering at the Technical University of Aachen 1980-1984 from which he proceeded to study process engineering at the Technical University of Stuttgart 1986-1992. Dr. Hoenig obtained his PhD at the University of Stuttgart in energy process technology and conservation in 1992.

Previously he has been the head of the subdivision of Thermal Process Technology of the Plant Technology Department, and the head of the Plant Technology Department. Since 1997 he has held the position of the Head of the Environment and Plant Technology Department and since 2012 Managing Director VDZ GmbH research & technology.

Presentation

Energy and Resources Efficiency in the Cement Industry

Cement production belongs to the energy and resource intensive production processes. Cement production in Europe counts to 200 - 250 kt/a in the long-term average. For each ton of cement 1.3 tons of raw materials (limestone, marl, clay, sand) and 0.2 tons of other main constituants beneath clinker (blast furnace slag, gypsum, puzzolana etc.) are used. Fuel energy consumption is about 3,000 MJ /t cement.

Already for several decades the cement industry is trying to reduce the use of natural raw materials and fuels by replacing these by alternative materials coming from other industrial processes. Best example is blast furnace slag from steel production which can replace the burned intermediate product cement clinker in cement. On the other hand the substitution of natural fossil fuels like coal and oil by alternative fuels based on wastes has been pushed in the European cement industry, so that some EU countries are top users worldwide today. In Germany and Austria for example the replacement of fossil fuels has been increased up to more than 60% related to the total thermal energy demand of the industry. This has been achieved without negative impacts on product quality and emissions to the environment. By this the cement industry contributes already today significantly to limit the use of natural materials, but there are still potentials which shall be used in the future. Therefore more research, know-how-transfer and demonstration is needed, also across the borders of industrial sectors.