GB642323A - Kiln structure - Google Patents

Abstract

642,323. Kilns; recirculating combustion products. FERRO ENAMEL CORPORATION. July 30, 1947, No. 20640. Convention date, March 10, 1941. [Classes 51(i) and 51(ii)]. A kiln comprises walls defining a ware chamber heated by at least one burner, an air duct in one of the walls, a refractory inspirator in said duct which communicates with the burner and ware chamber, and means for moving air through the duct and inspirator whereby this air is preheated by hot gases withdrawn from the ware chamber and the mixture of preheated air and gases is conducted to the burner. The tunnel kiln shown is suitable for ceramic ware and comprises a firing zone F, heated by oppositely-disposed pairs of burners 2, 4, 5 and 6, and a cooling zone C having side walls formed by thin refractory panels 7, 8 and roof passages 13-16 through which combustion air for the burners is passed for preheating, this air being supplied by a blower 17 through a pipe 18 and admitted to the passages under the control of dampers 13<1>-16<1> operable in pairs 13<1>, 16<1> and 14<1>, 15<1>. The air for the burners 2 passes from the passages 13 and 16 through side passages 20, 21 to longitudinally-extending ducts 22, 23, each containing a refractory nozzle member 24 spaced from a venturi block 25. The space between the block and the nozzle communicates with the interior of the kiln through a passage 27 and opening 28 so that hot gases are withdrawn from the kiln by the action of the airstream and mixed with the preheated air supplied to the burners. The air for the burners 4, 5 and 6 is admitted from the passages 14 and 15 to longitudinally-extending ducts 29 and 30 (riot shown), each containing a similar nozzle 31 and Venturi block 32. The dampers 13<1>, 16<1> and the fuel valves 26 of the burners 2 are interconnected by electrical means of known type for simultaneous operation whereby the supply of air through the passages 13, 16 is increased automatically if the fuel valve is opened. The dampers 14<1>, 15<1> and the valves of the burners 4, 5 and 6 are similarly interconnected..