Multiphase flow importance in future nuclear process heat applications: energy alcohol by biomass gasification with HTR

For future nuclear process heat applications multiphase phenomena are very important in a three-fold sense: For the ability to produce high temperature heat, for the realization of a catastrophe-free nuclear energy technology and for the newly proposed carbondioxide-neutral energy system 'energy alcohol from biomass plus HTR'. The technology of the 'Coated Particle' with the multi-coating of ceramic coatings on microparticles on nuclear fuel for the HTR is the technological reason for the ability to produce high temperature heat from nuclear energy. It is produced by chemical vapour deposition in a fluidized bed, this is a two-phase-fluidized-bed/gaseous-to-solid-states-change by pyrolysis/multi-component/phenomenon. The new requirement of a catastrophe-free nuclear energy technology has led to the identification that the ingress of water droplets into the nuclear core of the HTR should be avoided by self-acting separation of droplets coming from the steam generator tube break before they can get into the core. The behaviour of the water/steam jet in the helium stream is a two-phase-flow/far-from-equilibrium-phase-change/two-component/phenomenon. The biggest challenge to the energy industry is the carbondioxide-climate-change-problem. The solution requires the reduction of the application of fossil primary energy carriers by the factor of about 5 for the world, and e.g. by the factors of about 13 for FRG and about 10 for Japan. As a contribution to the solution a new proposal has been made recently: the production of energy alcohol, e.g. methanol, on the basis 'biomass plus HTR'. The main part of the energy conversion process is the helium-heated fluidized bed steam gasification of biomass. This a two-phase-flow/solid-to-gaseous states-change/pyrolysis and chemical reaction/multi-component/phenomenon. (J.P.N.)