| 摘要 |
<p>Protection is sought for a process for producing calcium carbide from a charge consisting of lime and carbon-containing material by means of electrothermal action on the charge via electrodes. A novelty of the process is the fact that the charge is fed as an unbroken layer onto a moving closed conveyor comprising hinged connected trough-shaped sections. The layer is compacted until the most homogeneous possible structure is obtained, heated in at least three stages using groups of horizontally rotating cylindrical electrodes (5, 6, 7) in non-slip contact with the surface of the charge layer as the voltage on the electrodes is reduced during successive stages. In the first stage, heating is applied until a temperature of 800-1000 °C is reached to remove moisture and volatile components. In the second stage, heating is continued until a temperature is reached as close as possible to the temperature of the onset of carbide formation. In the third stage, heating is continued until the carbide-formation temperature is attained and that temperature is then maintained. The carbide thus obtained is then cooled naturally as it is moved along the conveyor (1) to the crusher feed zone.</p> |
