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Gas recycling

SGI-argon and nitrogen recycling systems for metal powder production

Description of SGI-gas recycling systems

SGI recycling systems are mainly used in the metal powder producing industry where large amounts of inert gases (500 – 5000 m3/h) are necessary for the atomization of metal.

In principle the gas which is used for powder atomization is recirculated in a closed loop. The gas pressure necessary fort he atomization process is generated by a compressor. The selected type of compressor depends on the required flow and final pressure. Anyway the machine used is an oil-free piston or screw compressor. Having passed the atomization tower the hot gas is separated from powder in the cyclon, then it is cooled down. Remaining particles will be separated in a cyclon filter and in a fine filter. The cleaning of the filter bags is done automatically during the atomization cycle acc. to the counterflow principle with atomization gas from the recycling circuit.

After the filter line the gas is sucked off by the compressor and recompressed again to the necessary final atomization pressure.

When the atomization is finished the recirculation system is separated from the atomization tower by valves, so that the gas remains within the recirculation system and is not contaminated.

Gas losses, as well as purge volumes, initial filling and emergency supply of the system are controlled by a liquid gas tank and evaporator.