METHOD AND DEVICE FOR SAMPLING GAS Russian patent published in 2001 - IPC

FIELD: gas analysis; monitoring systems; heat-power engineering, power engineering, metallurgy and chemical industry. SUBSTANCE: method consists in transfer of gas from medium under test to gas-supply line under action of rarefaction followed by discharge of gas to medium under test. Rarefaction is created by jet of air directed through ejector and formed under action of difference of pressures in surrounding medium and in flow of medium under test. Discharge of gas is effected by introducing it into directed jet of air. Gas sampling unit includes gas drawing member, gas-supply line and ejector which consists of diffuser connected with gas volume, confuser and cylindrical passage located between them. Outlet of gas-supply line is brought into cylindrical passage. Confuser is connected with surrounding medium. Relationship of confuser and diffuser sizes are dictated by required rarefaction in cylindrical passage which shall be sufficient for setting the gas in motion through gas discharge line. According to another version, said device is provided with dehumidifier made in the form of porous ring fitted in body coaxially relative to ejector. External diameter of ejector is lesser than inner diameter of body. Butt ends of diffuser and confuser are matched with butt ends of device and are provided with units for sealing-up the cavity formed between body and ejector. Its cylindrical passage is connected with outlet of gas-supply line whose inlet is connected to cavity located between body and ejector and is connected with gaseous medium. EFFECT: enhanced reliability of sample at the lowest power requirements and labor consumption. 13 cl, 4 dwg