Ash handling in biomass power plant

The fly ash contained in the flue gas is normally removed in electrostatic precipitators (ESPs) or baghouse filters. Depending on the level of unburnt carbon and other residues, the collected fly ash is used as a raw material for the cement industry. The fly ash is sorted depending on the unburnt carbon content, and then transported to several different vessels and silos using air or vacuum transport in pipes.

Measurement of bulk fly ash during handling or in the silo is a challenge; uneven surfaces, different moisture levels and high levels of dust need to be overcome. KROHNE pioneered radar level measurement technology for process applications and today offers a broad range of sophisticated FMCW and TDR based radar technologies for use on liquids and almost all kinds of solids applications. The OPTIFLEX 2200 TDR level meter is the first choice for applications in the fly ash transportation system, despite the heat, dust and low dielectric constant of the ash itself. The patented drop antenna of the OPTIWAVE 6500 avoids the dust build-up that can occur in metallic horns, and drastically improves the availability of the instrument for level measurement applications in the fly ash silo. The OPTIBAR DP 7060 C offers low range DP measuring cells for monitoring the differential pressure within the ESP’s or the baghouse filters.