Apparatus for obtaining combustion gases of high calorific value

Apparatus for producing combustion gases of high calorific value, comprising:

• (a) means defining a vertical heating zone (6) having upper and lower ends;
• (b) means defining in said heating zone a descending fluidized bed (1) of non-carbonaceous solid particles;
• (c) heating means (8) for indirectly heating said non-carbonaceous, solid particles, said heating means including an external combustion chamber (32) for generating a heat exchanging medium, and tubular members (13) arranged in said solid particle bed and through which said heat exchanging medium is supplied;
• (d) means defining a vertical reaction zone (3) having upper and lower ends;
• (e) means (34) for supplying carbonaceous material to at least one of said heating and reaction zones;
• (f) first transfer passage means (7) for transferring the heated solid particles from the bottom of said heating zone to the bottom of said reaction zone;
• (g) first fluidizing means (4) for producing in said reaction zone an upwardly ascending fluidized bed of said heated solid particles, whereby carbonaceous fuel is allothermically gasified in a fluidized layer;
• (h) second transfer passage means (16) for transferring the gasified solid particles from the upper end of said reaction zone to a separating and discharging zone (5) arranged above said heating zone;
• and
• (i) separating and discharging means (5, 5′) arranged in said separating and discharging zone for separating the combustion gases from the gasified solid particles, said separating and discharging means being operable to discharge the combustion gases upwardly from said separating and discharging zone, and to return said non-carbonaceous solid particles to the upper end of said heating zone.