A Fast Network Flow Model is used in conjunction with Measurements of Filter Permeability to calculate the Performance of Hot Gas Filters
Two different technologies that are being considered for generating electric power on a large scale by burning coal are Pressurized Fluid Bed Combustion (PFBC) systems and Integrated Gasification and Combined Cycle (IGCC) systems. Particulate emission regulations that have been proposed for future systems may require that these systems be fitted with large scale Hot Gas Clean-Up (HGCU) filtration systems that would remove the fine particulate matter from the hot gas streams that are generated by PFBC and IGCC systems. These hot gas filtration systems are geometrically and aerodynamically complex. They typically are constructed with large arrays of ceramic candle filter elements (CFE). The successful design of these systems require an accurate assessment of the rate at which mechanical energy of the gas flow is dissipated as it passes through the filter containment vessel and the individual candle filter elements that make up the system. Because the filtration medium is typically made of a porous ceramic material having open pore sizes that are much smaller than the dimensions of the containment vessel, the filtration medium is usually considered to be a permeable medium that follows Darcy's law. The permeability constant that is measured in the lab is considered to be a function of the filtration medium only and is usually assumed to apply equally to all the filters in the vessel as if the flow were divided evenly among all the filter elements. In general, the flow of gas through each individual CFE will depend not only on the geometrical characteristics of the filtration medium, but also on the local mean flows in the filter containment vessel that a particular filter element sees. The flow inside the CFE core, through the system manifolds, and inside the containment vessel itself will be coupled to the flow in the filter medium by various Reynolds number effects. For any given filter containment vessel, since the mean flows are different in different locations inside the vessel, the flow of gas through an individual CFE will adjust itself to accommodate the local mean flows that prevail in its general location. In some locations this adjustment will take place at High Reynolds numbers and in other locations this will occur at low Reynolds numbers. The analysis done here investigates the nature of this coupling.
- Research Organization:
- National Energy Technology Lab., Morgantown, WV (US)
- Sponsoring Organization:
- USDOE Office of Fossil Energy (FE) (US)
- OSTI ID:
- 835929
- Resource Relation:
- Conference: 5th International Symposium on Gas Cleaning at High Temperatures, Morgantown, WV (US), 09/17/2002--09/20/2002; Other Information: PBD: 19 Sep 2002
- Country of Publication:
- United States
- Language:
- English
Similar Records
Advanced hot-gas filter development
Determination of filter-cake thicknesses from on-line flow measurements and gas/particle transport modeling
Related Subjects
20 FOSSIL-FUELED POWER PLANTS
CERAMICS
CLEANING
COAL
COMBINED CYCLES
COMBUSTION
CONTAINMENT
DIMENSIONS
ELECTRIC POWER
FILTRATION
FLOW MODELS
GAS FLOW
GASIFICATION
PARTICULATES
PERMEABILITY
REGULATIONS
REYNOLDS NUMBER
CERAMIC BARRIER FILTERS
GAS CLEANING
POROUS MEDIUM
CLEAN COAL