Patent ID: 9175439
Filing Date: 2015-11-03
Classification: C04B,C10J,D21C,F27D

Abstract:
1. A method for arranging a ceramic barrier in a gasifying reactor, which reactor is arranged to convert high energy organic waste of black liquor type with a large amount of organic or inorganic alkali metal compounds, by high temperature oxidation with air or oxygen, whereby the organic waste is converted to a hot reducing gas containing a considerable amount of water vapor and the inorganic compounds form an alkali-containing salt melt at a temperature of 750-1150° C., and which reactor is arranged to comprise an outer shell with associated inlet and outlet devices for reactants and products, the method comprising arranging a ceramic lining comprising one or more ceramic barrier layers on the inner side of the shell, arranging the total thickness and the thermal conductivity of the lining such that an inner surface of the lining facing the reaction chamber gets a high enough temperature for the formed salt melt getting in contact with this surface to have a high enough volume part of melt in order to flow freely on this surface, and the temperature in the rest of the lining, which is positioned closer to the outer shell, being low enough for the formed salt melt, that by capillary forces or hydrostatic forces strives to penetrate cavities in the form of joints, cracks or porosities in said one or more ceramic barrier layers, to solidify to form solid salts at a location within said one or more ceramic barrier layers, and that the temperature of the reactor shell is controlled in order to prevent detrimental over-temperatures on the reactor shell, the ceramic lining having an innermost ceramic barrier constructed to be in direct contact with the salt melt and an outer ceramic barrier constructed to allow the salt melt to solidify within the outer ceramic barrier, wherein the innermost ceramic barrier of the reactor comprising a lining material that consists essentially of compounds of aluminium oxide (Al 2 O 3 ) and at least one of alkali metal oxides (Me 2 ( I )O) and alkaline earth metal oxides (Me( II )O), forming compounds of the type Me 2 ( I )OAl 2 O 3 and Me( II )OAl 2 O 3 , and the outer ceramic barrier having a lower thermal conductivity than the inner ceramic barrier layer.