Integration, control, and testing of a high-temperature particle-to-sCO2 heat exchanger

Abstract

The development of a particle-to-sCO2 heat exchanger is a critical step toward the realization of a particle-based CSP system. In this paper, the work on the integration and future testing of a 100 kWt moving packed-bed heat exchanger prototype is reported. The device will be integrated with the falling particle receiver test loop at Sandia National Laboratories and integrated with a high-pressure sCO2 flow loop for heat rejection. A testing campaign is described including low-temperature (< 700 °C) ground-based testing where the particles will be heated using electrical energy prior to lifting the heat exchanger to the top of the tower for on-sun testing targeting sCO2 temperature > 700 °C. Furthermore, the development of an sCO2 mixing Tee is described, which allows for the sCO2 flow loop to be operated at temperatures over 700 °C without requiring high-temperature heat rejection or significant amounts of high-nickel piping.