Coal gasifier wall protection system

Technical Report · Tue Apr 01 04:00:00 EST 1980

OSTI ID:6835845

Excessive slag accumulation on the walls of small, high mass flux coal gasifiers can seriously reduce their operating efficiency. Thickly deposited layers of slag interfere with proper mixing and reaction, particularly in recirculation regions around injectors. As a consequence, the full potential of these coal conversion systems are only partially realized. One such system, currently under development, is the Bell HMF Gasifier. Part of its overall development deals with liner systems not only from the standpoint of erosion and corrosion, but also with respect to slag accumulation. Current approaches to gasifier inner wall design utilize refractories to which slag readily adheres. An approach to preventing this would be to select materials that are non-wetting to slag. Furthermore, there is evidence that chilled surfaces prevent slag adherence. The approach used in this study was to test wall systems which combined both slag repellant materials and active cooling to determine their effectiveness in reducing slag accumulation. The results of these tests show that the adherence of slag deposits sprayed onto actively cooled materials depends on wetting tendency, surface temperature, and surface roughness. For example, liquid slag accumulates on ceramic oxides partly because they have a strong wetting tendency. Moreover, because of comparatively low thermal conductivity and tensile strength, cooling to sufficiently low temperature to inhibit slag adherence risks thermal shock failure. On the other hand, smooth alloys and carbon/graphites chilled to sufficiently low surface temperatures provide a basis for designing effective slag free wall protection systems for high mass flux slagging gasifiers.

• Research Organization: Bell Aerospace Textron, Buffalo, NY (USA)
• OSTI ID: 6835845
• Report Number(s): NYSERDA-80-5
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
36 MATERIALS SCIENCE
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
360205 -- Ceramics
Cermets
& Refractories-- Corrosion & Erosion
ADHESION
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BORON COMPOUNDS
BORON NITRIDES
CARBIDES
CARBON
CARBON COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
COAL GASIFICATION
COAL GASIFICATION PLANTS
COMPARATIVE EVALUATIONS
CORROSION
CORROSION RESISTANT ALLOYS
DATA
ELEMENTS
EROSION
EXPERIMENTAL DATA
GASIFICATION
GRAPHITE
HAYNES 188 ALLOY
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INDUSTRIAL PLANTS
INFORMATION
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
IRON ALLOYS
IRON BASE ALLOYS
LINERS
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MATERIALS
METALS
MINERALS
MULLITE
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ADDITIONS
NIOBIUM ALLOYS
NITRIDES
NITROGEN COMPOUNDS
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
REFRACTORIES
SILICON CARBIDES
SILICON COMPOUNDS
SLAGS
SPINELS
STAINLESS STEEL-304
STAINLESS STEEL-347
STAINLESS STEELS
STEELS
TEMPERATURE DEPENDENCE
THERMOCHEMICAL PROCESSES
WETTABILITY