| 摘要 |
1. A process for the reduction of the content of water and ash formers in crude coal tars by means of a three-phase decanting centrifuge with the usual barriers and discharge devices at elevated temperature, characterized in that the crude tar - where appropriate pre-treated - is continously separated into an aqueous phase, a tar phase and a solid phase in the three-phase decanting centrifuge at a centrifuging number of between 1000 and 3000 g, provided with an open one- or two-threaded, preferably armoured worm, at e temperature of between 60 and 105 degrees C, an average dwell period of the tar of between 30 and 80 sec and a differential rotational speed between the worm and the rotor of from 10 to 50 min**-1 , the feed being periodically briefly interrupted during the continous operation. |
