GB755397A - A shaft furnace - Google Patents

Abstract

755,397. Shaft furnaces. STAMICARBON N.V. Oct. 25, 1954 [Oct. 29, 1953], No. 30684/54. Class 51(2). A shaft furnace used in high temperature reactions such as the production of calcium carbide, comprises a charging hopper 2 with bell valves 3 and 4, a central section in the form of concentric shafts 8 and 9, a hearth section 12 provided with spaced tuyeres 13, and an offtake 10 removing gases from an annular space 15 above the bottom of the inner shaft 9. The said inner shaft 9 comprises a cylindrical shoot 7 tapering off at 17 to a discharge shoot and formed with a downwardly and outwardly flaring skirt 16, surmounted by a part-conical reversible shoot 6, pivoted on a horizontal axis 5 to present either a narrow or a wide opening below the bell valve 4. The annular space 15 is defined by the lower inner shoot wall 17, the flared skirt 16, and the charge material in the outer annular shaft 8. In the manufacture of calcium carbide, coke is fed into the annular shaft 8 over the bell valve 4 and over the rotatable shoot 5, lime or a lime/coke mixture is fed into the inner shaft 9 over the bell valve 4 and through the reversed shoot 5, and oxygen or an oxygen/air or an oxygen/ steam mixture is blown through the tuyeres 13, molten carbide being tapped off through holes (not shown) in the bottom or side walls.