US2215807A - Electrostatic gas cleaner - Google Patents

Description

Sekt 24,1940- G. c. DERRY A 2,215,807

ELECTROSTATIC GAS CLEANER H Filed Jue 2f 1939 2 Sheets-Sheet l GARD/VER c. DER/ey y @/Mz 7 @www uuwzey swt- 24, l940- G. c. DERHY l ELECTROSTATIC GAS CLEANER Filed lJune: 2, 1939 2 Sheets-Sheet 2 Iweaaoaf: NER c. DER/z v y @ma C? uwzey rotootool soot. I24, '1940 l 2,215,807 I' UNITED STATES PATENT orifice smo'rnos'rario des oceanen Gardner Derry, Sharon, Mass. Aopliootioo .tomo 2, leso, sorioi No. einen pianos. Y (on. isa-v) This invention relates to electrostatic gas To the right (lacing the drawing) ot the wall t,

cleaners and indirect heaters, and relates more similar chambers t are relativelyclosely spaced,

l particularly to combined air heaters and electrofor example, l" apart.

static gas cleaners. The hue gases enter through the gas inlet t,

Combined air heaters and electrostatic gas pass upwardly between the air chambers t to the cleaners utilizing vertical tubes with centrally left of the wall t, are then deflected by the upper suspended wires as electrodes, the heated gas to wall l, to pass between the air chambers t to be cleaned passing through the tubes and the the right of the wall t, and then pass out the gas air to be heated passing over the tubes have been outlet il.

w proposed heretofore. An improved form of such The high voltage insulators it are mounted lm a device is disclosed in my ico-pending applicain the walls it and support the metal electrode tion, serial No. 240,996,l med November iv, loro. supporting rods it which extend horizontally The present invention provides an electroabove the air chambers il.v The negative electrode static gas cleaner and air heater'dispensing-with wires iti are attached to 'the rods it and are Y Mt tubes and utilizing spaced pairs of plates, the suspended from same centrally down between w heated ses to be cleaned moving vertically bethose air chambers il arranged to the left of the tween the pairs oi plates and the air to be heated Wall t. The hOliZOntal beams it are attached moving between the plates o i each pair. ltlecto the lower ends of the wires it below the air trode wires suspended vertically between the Chambers t, and the Weights W are Suspended im pairs ofplates cooperate with the `plates acting from the beams it for maintaining the wires ,m

also as electrodes to precipitate solidparticles under teIlSGh from the gas stream into on undcnying conector. The rods Ml of which there are one for oooh A feature of this invention resides im providing of the rows of Wires Shown bv Fis. i, are cone two pass gas flow, the gas passing rst between nected in parallel and to the negative terminal om, pairs of plates spaced relatively far apart ar- 0f a Suitable high voltage direct Current Supply m ranged as an effective electrostatic precipitator Which mail be rectied alternating Current The and then between relatively closely spaced pairs metal walls it are connected to ground and t0 of plates for efficient air heating, the positive terminal oi. the current supply source. lAn object of the invention is to combine in one The air Chambers t are connected to the current fm relatively simple unit, an electrostatic precipita- Supply Source through the walls it and plates, it m tor and anindirect heat exchanger. (Fie. 4) and form positive electrodesotner objects of the invention will be apparent The lower Walls 39 converse to form a onoler from the following descripi-.ion and from the hopper below the unit 'l for collecting the einden:` drawings. o r other solid particles precipitated from the gas. The invention will now be described with refer- As the nue gas passes upwardly between the w ence to the drawings, of which: air chambers t arranged to the left of the Fig. 1 is a front view of an assembled unit em- .wall t, it is ,ionized by the potential impressed bodying this invention; between the wires i5 and the walls of the cham- Fig. 2 is a side view with a portion in section, bers il. Ions are formed near the negative wires l im .of the unit of Fig. l; I5 and .these ions travel towards the positively m Fig. 3 is a sectional view along the lines 3--3 Vcharged walls ofthe chambers t, colliding with, of Fig. 2; negatively charging and carrying with them, Fig, 4 is a sectional view along the lines d-l cinders and other solid particles which are in of Fig. l, and their paths.v The negatively charged cinders then Fig. 5 is a projected view of one of the air strike and adhere to the chamber walls. r ,m heating chambers of Figs. 1 4. ln steam power plants for which the unit illus- Referring rst to Fig. 3 of the drawings, the trated was designed, the particles adhering to the central vertical wall 6 divides the unit .'l `into Walls are expected to agglomerate and form large two passages for gas flow. To the left (facing particles which will usually fall from the walls no the drawing) of the wall 6, the air chambers t, into the lower hopper. lfbecause of water vapor .m the details of which are illustrated by Fig. 5, are. orother reasons, the particles adhere to the walls supported vertically and are spaced relatively far they may be easily dislodged by hand or apart. In a commercial embodiment for use with mechanically operated rappers .which vibrate the a steam powerplant, for example, they may be walls, and the wires I5.

spaced 6" apart: Due to the relatively great spacing between a the walls of those air chambers 8 arranged to the left of thewall 6, which spacing is necessary for electrical reasons, all of the heat it is desired to extract from the ue gases cannot be extracted without providing more widely spaced air chambers 6 than lare necessary for precipitating purposes. Accordingly, the right hand side of the unit contains relatively closely spaced air chambers 8, which receive the clean but still hot flue gas leaving the left hand side of th-e unit, and extract the desired quantity of heat from it.

The air chambers 8 as shown by Fig. 5, have walls which form a closed space except for the passages I9 and 20 which serve as inlets oroutlets as will be described. With reference to Fig. 5, the lower passage I9 serves as an air inlet and the upper passage 20 serves as an air outlet. The air in its passage through the chamber 8 is heated through the heat imparted to the walls of the chamber by the heat ue gases passing in contact with their exterior as has previously been described.

As shown by Fig. l` the air chambers 8 arranged to the right of the wall 6, receive air through the lower passages I9, this incoming and coldest air contacting the leaving and coldest gas leaving through the outlet II. The air leaving the upper passages 2.0 of the chambers 8 to the right of the wall 6 passes into the duct 2| which confines the air leaving the passages 20 from the right hand group of chambers 8 and guides it into the upper passages 20 of the left hand chambers 8. ber 8 through the lower passages I9. With this arrangement, the coldest air is in heat exchange with the coldest gas and as the air becomes heated, it is progressively in heat exchange with progressively hotter gas. Thus, the heated air leaving the lower passages I9 of the left hand chambers 8 is in heat exchange with the heated gases entering the unit.

The drawings are not intended to be to scale or to illustrate the number or arrangement of air heaters.

While one embodiment of the invention has been `described for the purpose of illustration, it should be understood that other apparatus and arrangements of apparatus may be suggested by thoseskilled in the art without departing from' the essence of the invention.

What is claimed is:

1. A combined gas cleaner and air heater comprising means including a plurality of spaced, parallel, vertical plates forming alternate gas and air passages, means for dividing said plates into two groups, a hopper below said groups, means forming a gas inlet passage into the gas passages of one of said groups between said hopper and the lower ends of said one of said groups, means for deecting the gas leaving the upper ends of said gas passages of said one of said groups into the upper ends of the gas passages of the other of said groups, said plates of said groups being so spaced that the gas passages of said one group are substantially wider than the gas passages of said other group, electric wires extending vertically in said gas passages of said one group, means for connecting high. potential electric .energy to said plates and said wires, means for passing air to be heated into and out of said air passages, andmeans forming a gas outlet passage at the lower ends of said other of said groups and between same and said hopper.

2. A combined gas cleaner land air heater comprising a plurality of spaced, parallel, vertical The air then leaves the left hand champlates forming vertically extending air chambers therebetween, means forming horizontal air passages into said chambers adjacent the upper and lower ends thereof, said chambers having upper and lower walls for forming with said plates air spaces which are closed except for said passages, means for dividing said chambers into two groups, the chambers of one of said groups being spaced apart a distance substantially greater than the distance between the chambers of the other of said groups, electric wires extending vertically between said chambers of said one of said groups, means for connecting high potential electric energy to said plates and to said wires, means for passing heated gas in between said chambers of said one of said groups, means for guiding the gas leaving said one of said groups in between the chambers at said other of said groups, means forming a gas inlet passage for the gas leaving said other of said groups, and means forming a duct connecting one of said air passages of one of said groups with one of said air passages of said other of said groups.

3. A combined gas cleaner and air heater comprising a plurality of spaced, parallel, vertical plates forming vertically extending air chambers therebetween, means forming horizontal air passages into said chambers adjacent the upper and lower ends thereof, said chambers having upper and lower walls for forming with said plates air spaces which are closed except for said passages, means for dividing said chambers into two groups, the chambers of one of said groups being spaced apart a distance substantially greater than the distance between the chambers of the other of said groups, electric wires extending vertically between said chambers of said one of said groups, means for connectingl high potential electric energy to said plates and to said wires, a hopper below said chambers, means for passing heated gas in between said chambers of said one of said groups and between the lower ends thereof and said hopper, means for guiding the gas leaving the upper ends of said one of said groups in between the chambers at the upper ends of said other of said groups, means forming a gas inlet passage for the gas leaving the lower ends of said other of said groups, and means forming a duct connecting one of said air passages of one of said groups with one of said air passages of said other of said groups.

4. A combined gas cleaner and air heater comprising a plurality of spaced, parallel, vertical plates forming vertically extending air chambers therebetween, means forming horizontal air passages into said chambers adjacent the upper and lower ends thereof, said chambers having upper and lower walls for forming with said plates air spaces which are closed except for said passages, means for dividing said chambers into two groups, the chambers of one of said groups being spaced apart a distance substantially greater than the distance between the chambers of the other of said groups, electric wires extending vertically between said chambers of Said one of saidgroups, means for connecting high potential electric energy to said plates and to said wires, a hoppe;` below said chambers, means for passing heated gas in between said chambers of said one of saidvgroups and betweenthe lower ends thereof and said hopper, means for guiding the gas leaving the upper ends of said one of said groups in between the chambers at the upper ends of said other of said groups, means forming a gas inlet passage for the gai leaving the lower ends o! said other of said groups. and means forming a duct connecting one of said air passages of one of said groups with the corresponding air passage of the other of said groups.

5. A combined gas cleaner and air heater cornprising a plurality of spaced, parallel, vertical plates forming vertically extending air chambers therebetween, means forming horizontal air passages into said chambers adjacent the upper and lower ends thereof, said chambers having upper and' lower walls for forming with said plates air spaces which are closed except for said passages, means for dividing said chambers into two groups, the chambers of one of said groups being spaced apart a distance substantially greater than the distance between the chambers of the other of said groups, electric Wires extending vertically between said chambers of said one of said groups,

means for connecting high potential electric energy to said plates and to said wires, a hopper below said chambers, means for passing heated gas in between said chambers of said one of said groups and between the lower ends thereof and said hopper, means for guiding the gas leaving the upper ends of said one of said groups in between the chambers at the upper ends of said other of said groups, means forming a gas inlet passage for the gas leaving the lower ends of said other of said groups, means for passing `air to be heated into the lower of said air passages of said other of said groups, a duct connecting the upper gas passages of said groups, and means for passing the heated air out of the lower passage of said one of said groups.

GARDNER C. DERBY.

Images