GB2010706A - Centrifuges - Google Patents

Abstract

A centrifuging system is described in which the centrifuge is located in a container which can be sealed by means of a lid. Means is provided for supplying to the container an inert gas for purging the container and centrifuge of all oxygen and other combustible gases/vapours etc. before a centrifuging action to reduce the risk of explosion during a centrifuging action. Control means determines when a predetermined volume of gas has been purged through the equipment and an interlock provides that the purging process must be gone through completely before the centrifuging action can be begun. To this end the supply of material to be centrifuged is prevented until the complete purging process has been completed. The purging cycle is reset upon opening of the lid. An alarm is provided to indicate if the flow of gas to the container/centrifuge falls below a predetermined flow rate. A small positive pressure is maintained in the container during centrifuging and an alarm is provided to indicate if this small positive pressure drops. A second purging flow of inert gas is induced after the centrifuging action. In an alternative system the venting gases are analysed on an in-line basis and the centrifuging action including the supply of material to be centrifuged is inhibited until the analysis indicates the level of oxygen to be below a given concentration. A warning signal is generated in the event that the oxygen level increases above a given level during the centrifuging. An interlock may be provided to cut-off the supply of material to the centrifuge if the small positive pressure drops during centrifuging. <IMAGE>