A Probe for Determining the Concentration and Distribution of Particle Size of Solid Matter Suspended in Flowing Gases

摘要

1,170,047. Gas analysis; measuring fluid-flow. BAHCO A.B. March 15, 1968 [March 17, 1967], No. 12808/68. Heading G1B. Apparatus for determining the concentration and distribution of particle size of particulate solid matter suspended in gases flowing in a duct 1 comprises a sampling member 7 having a central through passage wherein are arranged in series two cyclone-type separators with annular collection chambers 16, 24 and a filter 26. The gases enter through a passage 13 in a nozzle 12 and a rotary motion is imparted to the gases by guide vanes 18SP1/SP or an insert 17. Coarse particles in the gas stream enter an annular gap 20 and are collected in the chamber 16. Intermediate size particles enter a further gap 23 and are collected in the chamber 24, and the remaining five particles are retained by the filter 26. Gas flow through the apparatus in spite of the pressure reductions caused by the cyclonetype separators and the filter 26 is maintained by supply of compressed air to a conduit 29 leading to suitable ducting in the body 6. Also contained in the body 6 is a differential pressure flow-meter connected to conduits 47, 48 to measure the flow through the apparatus and this measured valve may be used to control the flow by regulating the compressed air supply to the conduit 29. In use after the apparatus has been in use for a known time so that a known quantity of gas has passed through the apparatus, it is dismantled and the particles collected in the chambers 16, 24 and the filter 26 are weighed. The differential pressure-flow meter, Fig. 2, comprises a plate 35 having an annular gap 37 between its edges and the housing of the apparatus, the gap leading to an annular chamber 38 connected to the conduit 47. A central opening 36 in the plate 35, forming part of the through passage of the apparatus leads to a passage 33. A gap 42 between the opening 36 and passage 33 communicates with an annular chamber 41 and thus with the conduit 48, the differential pressure between the chambers 38, 41 being dependent on the rate of flow of gases through the apparatus.