Patent ID: 7461799

Claim:
A method for industrial production of high dispersed powders, comprising the steps of: mixing material to be pulverized with high pressure working gas into a gas-solids suspension, conveying of the gas-solids suspension through acceleration nozzles to a pulverizing chamber of a counterjet pulverizer for autogenic pulverizing, conveying the pulverized gas-solids suspension to an intermediate tank, said steps of mixing, conveying to a pulverizing chamber and conveying to an intermediate tank comprising a pulverizing cycle, removing the gas from the gas-solids suspension and collecting the solids in the intermediate tank, returning solids from the intermediate tank to be pulverized together with new raw material till there is a desired circulation load, and continuing the process so that as much end product material is removed from the process as raw material is added to the process, and wherein said mixing step includes the step of feeding the material alternately into side by side double-valve feeders and balancing tanks, where a feed pressure in each double-valve feeder is higher than a regular feed pressure in an associated balancing tank, and synchronizing the double-valve feeders so that an after-pressure left in one double valve feeder after release of the material into the associated balancing tank is utilized as initial pressure in the other double-valve feeder after receipt of material therein.