APPARATUS FOR PRODUCING AND BLASTING SUBLIMABLE GRANULES ON DEMAND

摘要

A granulator and delivery system for sublimable CO2 granules (16) has workin g edges (38) rotatably supported for defining a cutting surface (40); a driver (48) for powering the working edges; a feeder (56) for advancing solid CO2 into contact with the working edges, the working edges removing the granules from the solid CO2; a duct (30) having an outlet (31), the granules being directed from the block to flow from the outlet; an eductor (20) having a material inlet (32), a gas inlet (26) and an eductor outlet (24), the materi al inlet being connected to the outlet; a delivery control valve (28) fluid connected between the gas inlet and a source of high pressure gas; a controller (54) responsive to an external signal (82) for: activating the driver, the feeder and the delivery control valve for delivery of granules from the duct in response to activation of the demand signal; deactivating a t least one of the driver and the feeder in response to either deactivation of the demand signal for halting production of the granules or for preventing consumption of all but a predetermined portion of the solid CO2; and reversi ng the feeder for permitting loading of a fresh quantity of solid CO2 into the granulator in response to a predetermined advance of the feeder, and resumin g operation of the granulator once the fresh quantity is loaded. Also disclose d is a method of producing and blasting sublimable dry ice granules.