Abstract: A burner having an air intake at atmospheric pressure, a gas (fuel) supply line and a combustion chamber in which gas from the latter line burns in the presence of atmospheric air drawn in from the intake, is provided with a swingable or rotatable flap-type valve member which controls the volume rate of flow of the air to the combustion site. According to the invention, the position of the valve member is controlled by a parameter generated by the air stream and in response to the pressure in the gas supply line to maintain the air factor (ratio of air to gas) substantially constant. To this end a membrane type pressure detector responds to the pressure in the gas supply line and is connected by a mechanical force transmission mechanism to the flap or other valve element.

Abstract: A burner having an air intake at atmospheric pressure, a gas (fuel) supply line and a combustion chamber in which gas from the latter line burns in the presence of atmospheric air drawn in from the intake, is provided with a swingable or rotatable flap-type valve member which controls the volume rate of flow of the air to the combustion site. According to the invention, the position of the valve member is controlled by a parameter generated by the air stream and in response to the pressure in the gas supply line to maintain the air factor (ratio of air to gas) substantially constant. To this end a membrane type pressure detector responds to the pressure in the gas supply line and is connected by a mechanical force transmission mechanism to the flap or other valve element.

Abstract: Fine-grained fuels such as coal are continuously degasified by a process wherein a fine-grained degasified residue is recirculated as a heat-carrying medium and is heated in a pneumatic conveyor line and then fed to a collecting vessel. A first partial stream of the heat-carrying medium is fed through a mixing zone together with the fuel to be subjected to dry distillation. A second partial stream of the heat-carrying medium is fed to a secondary degasification zone together with the mixture comprising the dry distillation residue. Volatile constituents are distilled from the mixture in the mixing zone and the secondary degasification zone and are fed to dust-collecting and condensing means. Degasified residue is recirculated to the pneumatic conveyor line.