METHOD OF SYNTHESIS OF POWDER-LIKE MATERIALS, MAINLY REFRACTORY MATERIALS AND A DEVICE FOR ITS REALIZATION Russian patent published in 2004 - IPC

FIELD: production of synthesized fine-dispersion powders.

SUBSTANCE: the invention presents a method and a device for production of synthesized fine-dispersion powders and is dealt with the technologies of their production, mainly production of powders of refractory materials. The offered method of synthesis provides for heating of a dense layer of a fusion mixture up to the temperature, that is lower than the initial temperature of the reaction of the synthesis. Then a stream of noble gas or a reagent heated up to the temperature of the beginning of the reaction of the synthesis is fed into the lower part of the working volume of the reactor. At that the gas stream hits the neighboring layers of the powder and transports the synthesized material into the upper free from the fusion mixture part of the working volume of the reactor, where the large part of the particles separates away from the transporting gas and gets again in the dense layer of the fusion mixture circulating in the working volume of the reactor. The waste gas together with the synthesized smallest particles is cooled and fed into the upper separation part of the reactor, where they are exposed to separation and fed into a stage of fine clearing and the corresponding amount of the initial fusion mixture is fed by a continuous or a discretely - continuous way into the working volume of the reactor. In process of the start and operation of the reactor the temperature in the zone of the stream and in the dense layer of the circulating fusion mixture is registered and adjusted by the change of the gas temperature and its consumption and the temperature of the walls of the reactor keeping them within limits of the given temperatures interval of the synthesis. The device for realization of the method is supplied with the systems of adjustable heating of the walls of the reactor cage and the gas at the inlet of the nozzles supplied with the gas consumption control units. Besides in the central part of the cage between the block of separation and the transport pipes there is a heat exchange device for refrigeration of the passing into the separation block gas together with suspended in it synthesized particles of the fusion mixture, and the collector of the commercial powder is additionally supplied with a weight-measuring unit of the material monitoring. The inlet branch-pipe is connected to the outlet of the twin-chamber feeder additionally supplied with a tap of a pressure release and a by-pass pipeline with a pressure regulator and connected to the pipeline of the compressed gas before a nozzle. Inside the dense layer of the circulating powder and in a zone of a stream flow of the high-enthalpy gas there are temperature detectors, and in the weight-measuring device there is a sensor of a material weight, output signals of which arrive into the input of the microprocessor and its outputs are connected to the thermoregulators used for heating of walls and gas, to the gas consumption regulator, and also to a control unit of the material consumption of the twin-chamber feeder twin-chamber feeder. The technical result is production of submicronic and nano-metric synthesized powders with adjustable phase and granulometric composition, in a continuous operational mode and with low specific power inputs.

EFFECT: the invention ensures production of submicronic and nano-metric synthesized powders with adjustable phase and granulometric composition at low specific power inputs.

5 cl, 3 dwg, 4 ex