Potassium seed activities in open-cycle MHD system: predictions using a multiphase multicomponent solution model

Conference · Sun Jan 01 04:00:00 EST 1978

OSTI ID:6320838

Hsu, C C; Johnson, C E

Although the importance of seed recovery in the open cycle coal fired MHD System has been established, complete understanding of the complex chemistry existing at high temperature between potassium seed and coal-ash constituents is still lacking. A multiphase, multicomponent solution model was developed by modifying the widely used NASA computer program for calculation of complex chemical equilibrium compositions to include a subroutine that calculates solution formation from the condensed phase species. This model has been used to predict the potassium activity in the K/sub 2/O + SiO/sub 2/, K/sub 2/O + SiO/sub 2/ Al/sub 2/O/sub 3/, K/sub 2/O + SiO/sub 2/ + MgO, and K/sub 2/O + SiO/sub 2/ + CaO systems over the temperature range of 2300 to 1200 K, in which condensed phase components (i.e., K/sub 2/SiO/sub 3/, K/sub 2/Si/sub 2/O/sub 5/...) were assumed to form an ideal solution. Calculations showed that the addition of Al/sub 2/O/sub 3/, CaO, or MgO to the K/sub 2/O + SiO/sub 2/ binary system resulted in an increase in potassium activity in the gas phase, especially for CaO. Such information improves our predictive capability and may be used in the selection of materials and in establishing optimum conditions for operation of the combustor-generator high-temperature air heater components of an open cycle MHD system. Further, the predictive capability of the program can be used to assess other, more suitable additives and in determining operating conditions for improved potassium seed recovery.

• Research Organization: Argonne National Lab., Evanston, IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6320838
• Report Number(s): CONF-780941-6
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
300104* -- MHD Generators-- Duct Engineering & Fluid Dynamics
ADDITIVES
AIR HEATERS
ALKALI METAL COMPOUNDS
ALKALI METALS
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
ASHES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
COAL-FIRED MHD GENERATORS
COMPUTER CALCULATIONS
DIRECT ENERGY CONVERTERS
ELEMENTS
EQUILIBRIUM
HEATERS
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MATERIALS
MATHEMATICAL MODELS
METALS
MHD GENERATORS
OPEN-CYCLE MHD GENERATORS
OXIDES
OXYGEN COMPOUNDS
POTASSIUM
POTASSIUM COMPOUNDS
POTASSIUM OXIDES
RECOVERY
RESIDUES
SEED RECOVERY
SEED-SLAG INTERACTIONS
SILICON COMPOUNDS
SILICON OXIDES