Moving bed granular filtration of fast pyrolysis char: granular flow rate study

Removal of particulate matter from condensable vapors using a moving bed granular filter

“…By manipulating granule flow rate and tracking char movement through the filter in a series of cold flow tests, El Hedok was able to establish a minimum granule rate that maintains filtration efficiencies above 99%. [37] He was also able to propose an optimal operating condition that would prevent excessive char accumulation in the filter bed.…”

“…The system is detailed elsewhere by El Hedok. [37] All temperature measurements are taken using Omega Engineering® brand type K thermocouples which feature chromel-alumel elements, capable of reading temperatures between -200 and +1350°C. A custom Omega Engineering® Profile Probe that takes multiple readings along its length was used to provide temperature readings that correspond to pressure reading locations throughout the bed of the MBGF.…”

“…The media used in this study is 3 mm x 1.5 mm river rock obtained from Red Flint Sand and Gravel® and was chosen due to its filtration ability demonstrated by previous research. [37] Due to the large amount of dust and sand mixed in with the media as received, both a sieving operation and a dust removal process was necessary in order to eliminate dust contamination through elutriation during filtration. A large tray sieve shaker was modified with a series of air nozzles to both remove the sand through a 0.058 mm screen and blow the dust away in one process.…”

“…The midrange feed rate of 16 kg/h was replicated twice while both the high and low range feed rates had a single replication for a total of 7 tests. The overall range of flow rates tested was based on the success of previous cold-flow testing [37] and the ability of the system to heat the granule media to the desired operating temperature of 475°C.…”