US2327197A - Cinder collector - Google Patents

Description

Aug, 194% R. L. LINCOLN 2,327,197

CINDER COLLECTOR Filed May 13, 1941 INVENTOR Eel/1N0 L. L NC 01.

ATTORNEY Patented Aug. 17, 1943' Roland L. Lincoln, Dedham, Mass, assigemr B. F. Sturtevant Companmfio'ston, Mass.

epu ation May 13, 1941, serial No.. 393,174

(01. 1ss so) 2 Claims.

This invention relates to, cinder and dust concentrators and collectors and relates more particularly to cinder concentrators for combination with induced draft fans. Y a

In industrial plants such for example, as steam power plants utilizing induced draft, fans, it is desired to separate cinders or other foreign particles from the gas before it enters the fans so as to avoid abrasion oi the blades of the fan wheels. I 1

This invention provides a compact, eflicient cinder concentrator and collector which may be mounted in the inlet casing of an induced draft fan. Deflectors for causingabrupt changes in direction inthe gas, maybe mounted in the casing, around the axial inlet into the fan Wheel. The gas entering through a tangential inlet, passes through the deflectors and the solid particles are thrown out by centrifugal vforce and are collected by a tangentially placed skimmer.

A feature of theinvention resides in the provision of a partition which extends a substantial distance around and adjacent the deflectors for preventing the gas from flowing through the deflectors before it has acquired the desired spin which is imparted by the tangential inlet and the curved casing Walls, and before it has acquired the desired velocity in its travel-in the converging channel provided between the dey fiectors and the walls of the casing.

Another feature of the invention resides inrthe provision of spaced parallel partitions extending perpendicular to the axis of the collector and which serve to prevent the formation of the double eddy currents which tend to form in planes perpendicular to the direction of gas flow.

Another feature of the invention resides in providing a second skimmer at the end of said partition and extending across the gas stream between the deflectors and the partition,

Objects of the invention are to improve the efliciency and to reduce the size of and the cost of collectors for removing solid particles from gases.

The invention will now be described with reference to the drawing, of which:

Fig. 1 is a side sectional view'of this invention embodied in the inlet of an induced draft fan, and

Fig. 2 is a side elevationwith a portion of the casing removed, of a portion of the fan and collector of Fig. 1. v

The fan illustrated has the volute inlet casing 5 with the tangential gas inlet 6. The casing 5 extends spirally around the axial inlet 1 into the fan wheel'8. The gas moved by the'ian wheel is discharged from the outlet 9. The construction described so far is old in the art and its details may be found in the U. S. Patent No.'1,8e6,- 853which issued Feb. 23, 1932 on an application of H. F. Hagen. g

The spaced deflectors [0 are arranged in a circular path in the inlet casing 5 and around the entrance to the inlet 1 into the fan wheel and serve to cause the gas flowing past them, to make abrupt changes in direction so as to throw out the entrained solid particles, by centrifugal force against thewallsof the casing.

The tangential skimming channel it is formed in the walls of the inlet casing 5'at a point about 270 from the inlet 6. The deflectors IB are so arranged'in the casing 5 that the gas passage between the walls of the casing and the deflectors decreases progressively iii-diameter up to the skimming channel ll. 7 r

The partition l2 forms within the'casing 5 an extension of the wall! of the casing, the two being formed in a circular segment which terminates in the pocket M formed between-the lower end of the partition l2 and the wall l5 spaced inwardly therefrom.v The partition I2 extends a substantial distance Which as illustrated may be more than one-third of the way,

from the inlet 6 into the casing 5; forms with the curved walls of the casing 5, a converging gas path, and serves to prevent the gas from passing directly between the upper deflectors In, those adjacent the inlet 6, into the fan wheel. The gas cannot pass between the deflectors until it has passed the lower end of the partition 12, at which time it has developed sufiicient spin and its velocity has increased so that the separation due to centrifugal force is considerably of the invention in so far as the above described functioning of the partition I2 is concerned and may be omitted without detracting from the value of the partition 12. With the pocket [4 omitted, the gas passing the lower end of the partition [2 will be recirculated, collection taking place in each circuit at the skimming channel H.

The skimming channel Il may be connected to the inlet of a cyclone type secondary collector which will remove the solid particles which are concentrated in the gas stream passing into the skimming channel I l.

Due to the motion of the gas around the inside of the spiral walls of the inlet casing 5, it tends to form the double eddy currents asillustrated by the arrows in the lower portion of Fig. 2. These eddy currents tend to take the solid par ticles concentrated by centrifugal force in the outer portions of the curved gas path, and to feed them back into the innerrportions of the gas path thus decreasing the effectiveness ofthe desired concentration and separation. By providing the partitions l8 which extend in parallel planes perpendicular to the axi of the fan, from the point IS in the inlet portion of the casing 5, torthe skimming channel; H, the double'eddy currents are prevented from forming. As illustrated by'Figs. 1 and 2,. the partitions l8 contact the outer wall. of the inlet casing andextend inwardlzya substantial distance towards the deflectors i-hisinvention may be used not only to collect cinders and fly ash from theflue: gases of steam power plants, but may be used for collecting solid particles of any substance from any form 0t gas.

plurality of spaced deflectors arranged in a substantially circular path in said casing around said outlet for causing abrupt changes in the direction of the gas entering said outlet, means forming a tangential skimming channel in said wall for collecting dust thrown thereagainst by centrifugal force, a partition extending at one end from said channel in a substantially circular arc in the direction of gas flow around not sub stantially less than half of said deflectors and extending into said passage toward said wall and substantially converging said passage, said partition forming between its outer side and said Wall a converging passage for the gas in said casing and forming between its inner side and said deflectors, another gas passage for the gas passing said channel, and means at the other end of said partition forming another skimming channel for the dust thrown out by centrifugal force against said inner side of said partition.

2. A dust collector comprising a casing having an outer curved wall, a tangential inlet passage for dust laden gas, an axial clean gas outlet, a plurality of spaced deflectors arranged in asubstantially circular path in said casing around said outlet for causing abrupt changes in the direc tion of the gas entering said outlet, means forming a tangential skimming channel in said wall for collecting dust thrown thereagainstby centrifugal force, a partition extending at one end from said channel in a substantially circular arc in the direction of gas flow around a plurality of said' d'eflectors, said partition forming between its outer side andsaid' wall a converging passage for the gas in said casing and forming between its inner side and said last mentioned plurality of said deflectors, another gas passage for the gas passing said channel, and means at the other end of said partition forming another skimming channel for the dust thrown out by centrifugal force against said inner side of said partition.

' ROLAND L. LINCOLN.-

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