Moving-bed heat exchanger

A moving-bed heat exchanger (MBHE) is a heat exchanger that transfers heat between a fluid and a solid granular material using continuous downward flow (often gravity-driven) past a surface (tube, plate, funnel, et cetera). They are widely used in industry, on applications involving heat recovery (providing a high volumetric transfer area) and filtering (avoiding common operational problems in fixed bed or ceramic filters like the pressure drop increase during operation).

Source: Wikipedia — Moving-bed heat exchanger (CC BY-SA 4.0)