Particle Conveyance in a Particle-driven CSP Loop: Design, Operation, Attrition and Erosion

A novel concentrated solar power (CSP) system employing particle-driven technology is currently being scaled to multi-megawatt capacity under the EU Horizon Europe’s “powder-to-powder” (P2P) initiative. The system integrates a fluidized bed-in-tube solar receiver, down-comer assembly, particle-based PV super-heater, thermal storage/power generation unit, and pneumatic particle re-circulation system. Engineering analysis confirms the feasibility of conveying 16 tph particles through a 0.20 m diameter insulated vertical pipe, achieving 250 mbar pressure drop over 100 m elevation with specific energy consumption of 0.35 kW/ton - 53% lower than conventional bucket elevators. Material selection studies identify AISI 410 for riser/screw conveyors and AISI 310 for down-comer construction, with erosion analysis projecting a 16-24 year component lifespan. Experimental data demonstrate a controlled particle attrition (<0.1% per cycle) through optimized dense-phase riser and stick-slip down-comer operation. Thermal modeling reveals heat losses below 3% when implementing riser outlet air heat recovery, with additional efficiency gains achievable through solid/air mass flow ratios exceeding 15:1. While confirming large-scale applicability of all unit operations, the study notes potential geometric modifications that may enhance thermodynamic performance in full-scale implementation. The integrated design demonstrates significant advancements in CSP efficiency through particle-based heat capture, storage and recovery optimization and robust material engineering solutions.