Patent GB-190304821-A (GB)
Title: Improvements in Apparatus for the Manufacture of Cement
Inventor: CARPENTER ROLLA CLINTON
Filed: 1903-03-02
Granted: 1903-07-16
Abstract: 4821. Carpenter, R. C. March 2. Cement kilns.-Relates to rotary kilns for making cement, and to steam generators, drying, and heating apparatus for utilizing the waste heat from the kilns. In the apparatus shown in Fig. 1, two cylindrical kilns A, inclined to the delivery end B, are rotated by the usual gearing A<1>, and are heated by oil, gas, or powdered fuel, supplied by burner tubes B<1>. The hot waste gases from the kiln are drawn by a fan F through a steam generator G and a superheater or an economizer E, and escape through the stack F<1>. The boiler G is fitted with widely-spaced vertical water tubes G<3>, doors G<2>, and a central partition G<4>, and can be heated by an independent auxiliary furnace H. When desired, the gases can be drawn directly from the kiln into the smoke-stack through flues E<4> and a passage E<2> fitted with dampers E<5>, E<6>, which can be half closed to direct a portion of the gases through the economizer, or the gases may pass through the boiler only, or the economizer. The cement clinker from the kilns passes down inclined shoots B<2>, lined with refractory material, and is elevated by an endless chain of buckets B<5> to a cooling-tower C fitted with inclined plates or slides C<2> to form a staggered passage. Air for combustion in the kilns is heated by forcing it through a pipe C<5>, the tower C, elevator and shoots B<2>, in a direction opposite to the motion of the cement. The cement accumulates at the bottom of the cooling- chamber, and is removed through apertures closed normally by a horizontal slide operated by a rack and pinion. Doors C<3>, C<4>, C<6>, H' are provided for the admission of air &c. In a modification shown in Figs. 9 and 10, air for combustion is forced by a fan D<4> through the cooling-chamber D and elevator casing C' into a pair of rotary kilns A, and powdered coal or other fuel is supplied by blasts of air through double burners B, which are fitted with flexible joints and can be directed to any part of the kiln. The hot gases from the kilns are conducted through side passages E<1> to a water-tube boiler F<7> fitted with fireproof partitions F<4> for directing the gases in a zig-zag manner between the tubes. An auxiliary furnace F<1> is provided under a combustion-arch F<2>, and the waste gases from the boiler casing are conducted to rotary dryers H, for drying liquid cement, and are drawn off by a fan L<1> and stack L. The liquid cement is heated by passing it in a zig-zag manner through parallel tubes of a condenser 0 heated by exhaust steam from engines, which operate the plant and may be supplied by the boiler F<7>. The hot liquid cement is conducted by pipes to the upper ends of the dryers which are provided with longitudinal stirring-ribs H<1>, and may be heated by auxiliary furnaces K<1>. The gases from these furnaces pass round the drying- drums and through passages to the lower ends of the drums, through which they are drawn by the fan. The dried cement falls from the lower ends of the drums, and is removed by screw conveyers H'.