Gas and liquid contact apparatus – Fluid distribution – Valved
Patent
1984-09-19
1986-03-25
Miles, Tim
Gas and liquid contact apparatus
Fluid distribution
Valved
261112, 261DIG54, 261118, B01F 304
Patent
active
045782261
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a venturi scrubber for dust-laden flowing gases, comprising an intake portion whose duct through which the gas flows is of a cross-section that progressively decreases in the flow direction, and an annular duct for a fluid, which annular duct is arranged adjacent the largest-diameter end of the intake portion and is connected over its entire periphery to the inlet portion duct through which the gas flows, wherein at least one feed conduit for the fluid opens into the annular duct in such a way that the fluid flows into the annular duct with a tangential component.
Venturi scrubbers of that kind generally comprise three portions, namely an intake portion, a central portion and a diffuser. By virtue of the cross-section of the intake portion decreasing in the direction of flow, the speed of the gas flowing therein is increased. The wall of the intake portion is formed on the lines of a venturi pipe or, for the sake of simplicity, is internally of a conical configuration. The central portion which adjoins the intake portion is of the narrowest cross-section so that the gas speed there is at its greatest. At that point, a fluid, normally water, is sprayed into the free cross-section of the central portion; the fluid is broken up into very fine droplets by the high-speed gas flow and is entrained therein. In particular by virtue of the difference in speed between the droplets of fluid and the solid particles to be removed in the gas flow, the solid particles are deposited on the droplets of water. In the diffuser-shaped enlarged portion downstream of the central portion, the speed of the gas flow falls again. The pressure drop which occurs when the gas flows through the narrowest part is partially recovered when that happens. The gas-water-solid mix is then passed through a suitable piece of apparatus, for example a cyclone, within which the dust-laden droplets of water are separated out of the gas flow, thus producing a gas of the desired degree of cleanliness. The water used for causing the dust to be deposited on the water droplets can be recycled a number of times. The step of separating the dust from the water is advantageously carried out in a sedimentation tank.
The operation of injecting the water required for separation of the solid particles is generally effected, as considered in the direction of flow, at the beginning of the narrowest cross-section in the central portion. The gas speed is at its highest at that point so that the water introduced is accordingly broken up into particularly fine droplets.
Difficulties are frequently encountered by virtue of the fact that solid particles are deposited on the inside wall surface of the venturi scrubber, in particular in the intake portion thereof, upstream of the point, in the direction of flow, at which the water is injected into the unit. The resulting deposits of solid matter grow in opposition to the direction of flow of the gas, and such deposits may attain a magnitude and an extent that the flow conditions in the entire system are altered. In extreme cases, it may even happen that the venturi scrubber is completely blocked. To avoid such deposits and the difficulties which result therefrom, it is already known from U.S. Pat. No. 2,684,836 to provide an annular duct on a vertically disposed venturi scrubber, in the region of the largest diameter of the intake portion; from the annular duct go a plurality of peripherally extending pipe portions out of which a fluid, usually water, passes into the intake portion under a certain pressure, in such a way that the inside wall surface of the intake portion is acted upon by a layer of fluid which is intended to prevent solid particles from being deposited thereon. However, that arrangement does not guarantee that the fluid is uniformly distributed over the inside surface of the intake portion. In particular, adjacent the end of the largest diameter of the intake portion, there are areas which are not wetted by the fluid. A film of fluid that covers the entire wall surface is only fo
REFERENCES:
patent: 1307665 (1919-06-01), Guider
patent: 1741519 (1929-12-01), Huff
patent: 2684836 (1954-07-01), Arborgh et al.
patent: 3182977 (1965-05-01), Erni
patent: 3524630 (1970-08-01), Marion
patent: 3567194 (1971-03-01), Shah et al.
patent: 3601374 (1971-08-01), Wheeler
patent: 3758081 (1973-09-01), Prudhon
patent: 3804386 (1974-04-01), Arnold et al.
patent: 3959420 (1976-05-01), Geddes et al.
Adlhoch Wolfgang H.
Lambertz Johannes
Miles Tim
Rheinische Braunkohlenwerke AG
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