Survey on 20 years of research development on nuclear process heat applications in Germany

摘要

Germany looks back to more than two decades of comprehensive R&D activities onrnnon-electricity applications of nuclear power. Efforts were basically centered around the High-rnTemperature Gas-Cooled Reactor (HTGR) which is deemed to represent a suitable concept for safe,rnefficient, and economic generation of both electricity and heat for high temperature industrialrnprocesses including the production of hydrogen and/or liquid hydrocarbons for the transportationrnsector. Due to the large coal resources available, German activities starting in the 1970s were focusingrnon the utilization of nuclear energy in the heat-intensive process of coal gasification. The “PrototypernPlant Nuclear Process Heat” (PNP) project was launched in cooperation with partners from the coalrnand the nuclear industries with the main objectives to upgrade the pebble-bed HTGR for high coolantrnoutlet temperatures of 950℃ and to develop and test respective heat exchanging components.rnDifferent methods of gasification for the two types of coal, hard coal and brown coal (lignite), havernbeen developed for a power level representative for large and medium-sized plants (~125 MW) andrnsuccessfully tested in the 10 MW range demonstrating their industrial feasibility at a high reliability.rnFurther studies included the production of hydrogen by nuclear steam reforming of methane for energyrnstorage, transportation, and recovery of the stored energy. This closed-cycle process wasrnexperimentally verified under nuclear conditions at a 10 MW scale in the test facilities EVA andrnADAM. The particular safety aspects of a nuclear process heat complex have been studied in detailrntargeting, e.g., the tritium contamination of the product and the consequences of potential explosionsrnof flammable gas mixtures. Future activities should concentrate on a re-evaluation of the abovernmentioned studies from the past by comparing against current technologies and market conditions withrnthe goal to select highly promising projects, and should also include respective safety considerations.