Abstract: In a method of accelerating and pressurizing a fluidized stream of particulate material, e.g. for blast cleaning by ice particles, the stream flows through a constriction in a flow passage. A flow of blast medium is discharged from a blast nozzle at supersonic speed into the fluidized stream so as to form within the fluidized stream a flow front which is impenetrable by the fluidized stream and which co-operates with the constriction to form an effective nozzle for accelerating the fluidized stream. Grounding is provided controlling electrostatic charges for either better work effect or neutralization in unwanted or hazardous conditions, and safety pressure relief, blast intensity control, articulation and changement of final nozzles for effective operation are also provided.

Abstract: A fluidized particle production system includes a solidifying unit having a forming surface for supporting a solidified layer of a medium, e.g. ice and a treatment apparatus for removing the solidified medium from the solidifying surface and sizing the removed solidified medium into particles of desired dimensions. The treatment apparatus comprising a sizing device co-operating and moving with the solidifying surface for effecting therebetween the sizing of the particles. A housing encloses the solidifying unit and the treatment apparatus and a sweep fluid outlet is positioned to discharge sweep fluid towards the sizing device for fluidizing the particles and transporting the fluidized particles through an outlet duct from the housing.

Abstract: In a method of and apparatus for accelerating and pressurizing a fluidized stream of particulate material, e.g. for blast cleaning by ice particles, the stream flows through a constriction in a flow passage. A flow of blast medium is discharged from a blast nozzle at supersonic speed into the fluidized stream so as to form within the fluidized stream a flow front which is impenetrable by the fluidized stream and which co-operates with the constriction to form an effective nozzle for accelerating the fluidized stream. Grounding is provided controlling electrostatic charges for either better work effect or neutralization in unwanted or hazardous conditions, and safety pressure relief, blast intensity control, articulation and changement of final nozzles for effective operation are also provided.