Method for arranging a chemical barrier in a gasifying reactor for black liquor, a chemical gasifying reactor, a barrier layer of a reactor and a method for manufacturing a building block for such a barrier layer

A chemical reactor for the conversion of high energy organic waste of black liquor type with a large amount of organic or inorganic alkali metal compounds, by partial 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, hydrogen gas and carbon monoxide and the inorganic compounds form an alkali-containing salt melt at a temperature of about 750-1150° C., which reactor comprises:

• an outer shell having associated inlet and outlet devices for reactants and products as well as a ceramic lining arranged on the inner side of the shell and comprising one or more ceramic barrier layers, the total thickness and the thermal conductivity of the lining being chosen such that an inner surface of the lining facing the reaction chamber achieves a high enough temperature for the formed salt melt in contact with this surface during operation 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, remaining 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, solidifies to form solid salts at a location within said one or more ceramic barrier layers during operation;
• and
• a controller for controlling the temperature of the reactor shell to prevent detrimental over-temperatures on the reactor shell, wherein the ceramic lining is thermodynamically stable in the salt melt, 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, the innermost ceramic barrier of the reactor consists of compounds of aluminium oxide (Al2O3) and at least one of alkali metal oxides (Me2(I)O) and alkaline earth metal oxides (Me(II)O), forming compounds of the type Me2(I)OAl2O3 and Me(II)OAl2O3 and the outer ceramic barrier consisting of a material having a lower thermal conductivity than the inner ceramic barrier layer.

A chemical reactor for the conversion of high energy organic waste of black liquor type with a large amount of organic or inorganic alkali metal compounds, by partial 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, hydrogen gas and carbon monoxide and the inorganic compounds form an alkali-containing salt melt at a temperature of about 750-1150° C., which reactor comprises:

• an outer shell having associated inlet and outlet devices for reactants and products as well as a ceramic lining arranged on the inner side of the shell and comprising one or more ceramic barrier layers, the total thickness and the thermal conductivity of the lining being chosen such that an inner surface of the lining facing the reaction chamber achieves a high enough temperature for the formed salt melt in contact with this surface during operation 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, remaining 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, solidifies to form solid salts at a location within said one or more ceramic barrier layers during operation;
• and
• a controller for controlling the temperature of the reactor shell to prevent detrimental over-temperatures on the reactor shell, wherein the ceramic lining is thermodynamically stable in the salt melt, 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, the innermost ceramic barrier of the reactor comprises primarily compounds of aluminium oxide (Al2O3) and at least one of alkali metal oxides (Me2(I)O) and alkaline earth metal oxides (Me(II)O), forming compounds of the type Me2(I)OAl2O3 and Me(II)OAl2O3, wherein the innermost ceramic barrier is free of silica based materials, and the outer ceramic barrier having a lower thermal conductivity than the inner ceramic barrier layer.