GB767111A - Improvements in or relating to pottery kilns - Google Patents

Abstract

767,111. Continuous kilns. WEST MIDLANDS GAS BOARD. Dec. 10, 1954 [Dec. 14, 1953], No. 34710/53. Class 51 (2). In a pottery kiln wherein ware is passed through preheating, firing and cooling zones and which comprises work passages arranged in vertically-spaced layer formation, each layer consisting of horizontally-spaced passages, and heated by longitudinally disposed combustion chambers in the floor and roof of each layer of passages, burners introduce gaseous fuel into each combustion chamber with a deficiency of primary and/or secondary air, tertiary air being supplied to each chamber to complete combustion. The kiln shown comprises work passages 3 in the floor and roof of which are combustion chambers 4 subdivided by partitions 5. Ware is loaded on bats at kiln end 6 and pushed by hydraulic ram or the like to kiln end 10 passing in succession through preheat, firing and cooling zones 7, 8, 9. Burners 11 introduce gas and primary air into chambers 4, the burning gas being caused to flow along the chambers in the direction 15. The chambers 4 extend the full length of the kiln and secondary air is allowed to enter them under controlled conditions at kiln end 10, whilst tertiary air is supplied through pipes 12. The secondary air is preheated in the kiln cooling zone 9 and, if desired, a greater amount than is necessary may be so heated some being bled off before reaching the burners and used as preheated tertiary air. By varying the number of points of introduction of the tertiary air the temperature gradient in the work passages of the kiln may be changed. Cooling of the ware in zone 9 is effected by the introduction of air into the passages 3 at kiln end 10, this air being caused to flow in the direction 17 by draught applied to air flow controlled venting flues 13.