Improvements in or relating to the production of briquettes containing coal

摘要

A method of briquetting coal, coke, ore or mixtures thereof with caking coal comprises heating the non-plasticizable fraction of material to be briquetted to a temperature above that at which the caking coal becomes plastic, PICT:1064446/C4-C5/1 introducing the heated material and the caking coal into a mixer 26 having two elements 23 with lenticular profiles mounted on shafts 21, 22 (arranged side-by-side) which are rotated in the same direction, whereby the mixture attains a temperature in the range of plasticity of the caking coal, e.g. 350 DEG to 480 DEG C., cooling the mixture to at least 20 DEG C. below the temperature at which the caking coal is in its plastic condition with water (introduced at 30), and optionally with steam, and briquetting the mixture at that temperature in a press. Partial degassing and detarring occur in the mixer and volatiles and steam leave at 25. The caking coal, which may be preheated, enters at 24a, and two mixers may be employed in series, the water then being supplied only to the second. The temperature of the non-plasticizable fraction may be thermostatically controlled by a device located on a line connecting the two mixers, see Fig. 1 (not shown). A bin may be situated between the mixer and the press to provide a store of briquetting material and to act as a gas barrier. Four specific examples (giving temperatures, grain sizes, relative proportions) are described, the non-plasticizable fraction being respectively hard coke (in two examples), anthracite, and iron ore.ALSO:A method of briquetting ore, with or without coal or coke, with a caking coal, comprises heating the ore to a temperature above that at which the caking coal becomes plastic and passing the preheated ore and the caking coal through a mixer to plasticize and partially de-gas the coal, and cooling the mixture by the injection of water to at least 20 DEG C. below the temperature at which the coal plasticizes, and then briquetting the mixture in a press. In a specific embodiment, iron ore (grain size up to 3.0 mm.) is heated to 600 DEG C. and mixed with caking coal (grain size up to 2.0 mm.) preheated to 150 DEG C. in the proportion by weight of 70: 30. A mixing temperature of 450 DEG C. is attained, and the mixture is cooled by water to 400 DEG C. for briquetting in an extruder press.