733,373. Furnaces. BIGELOW-LIPTAK CORPORATION. Dec. 23, 1952 [Jan. 15, 1952], No. 32561/52. Class 51 (1). A furnace for burning refuse, in particular bagasse, comprises a U-shaped hearth or cell built up of a number of superimposed courses of refractory tiles some of which are formed with tuyeres therein, each course being retained in position by at least one U-shaped retaining member extending around the outside of the course. In the furnace shown (Figs. 1 and 2) two U-shaped cells are disposed within an outer casing 101 of walls 105, 122 and pillars 73, 75 against which the ends of the cells abut at 71. The casing is roofed at 109 and partitioned by a wall 121 and by a wall 119 provided with dampers 131 actuated by levers 133 at the front of the furnace. The walls 119 and 122 form a plenum chamber 123 into which air is blown by a blower 125 for passage via the dampers to the spaces 115, 117, defined in part by the wall 121, surrounding the cells from whence it enters the cells through the various openings provided. The bottom course (Fig. 4) of each cell comprises hollow metal blocks 49 (Fig. 5), 51 (Fig. 6), for the supply of primary air, which are bolted to the floor 23 the blocks 49 being interlocked with solid filler tiles 69. When the blocks 49, 51 are placed in position next to each other the openings 61, 61<SP>1</SP> are in alignment so that the interiors of the blocks are in communication throughout the entire length of the course. The blocks and tiles 69 are provided with notches such as 65 in 49, and 65<SP>1</SP>, 67<SP>1</SP> in 51, so that two U-shaped retaining members 63 may be engaged therein thus holding the course in position against the abutments 71. The members 63 pass through the furnace front wall and are clamped thereagainst. The curved section of the course may be formed by tapering the blocks or by filling in with tapered tiles such as 81, 95<SP>1</SP>, shown in Figs. 8 and 11. The pillars 73, 75 are provided with blocks 49, 51, air being passed thereto through passages 153 formed in the pillars and communicating with the spaces 115, 117. On top of the bottom course may be placed a course of solid interlocking tiles 91 suitable wedge-shaped tiles being used for the curved sections. The third course of tiles in the cell wall may be formed of blocks 91, 95 (Fig. 10), the latter being of left- and right-hand sections to form therebetween tuyeres 97 for the passage of secondary air. The curved section comprises wedge-shaped tuyere tiles alternating with suitable solid ones. The fourth course of tiles may be similar to the second and the fifth similar to the third a top course being formed of tiles 91 with suitable masonry filling connecting their tops to the suspended side walls of the furnace. All the courses subsequent to the first have only one retaining member 63 to hold them in position. In operation bagasse is fed through shoots 25 on to the floor 23 of each cell the products of combustion from each cell intermingling and passing upwards through throat 3 and over the arch 5 and boiler tubes (not shown), any solid unburnt fuel descending to be collected in a pipe 37 for steam blown delivery through tubes 43 back to the cells. The cells may be operated separately if so desired. In another embodiment of the invention the bagasse is fed through the top of a furnace having upwardly tiltable cell floors of the type disclosed in Specification 733,374.