US1831319A

US1831319A - Gas supply apparatus

Info

Publication number: US1831319A
Application number: US260117A
Authority: US
Inventors: Gerald D Peet
Original assignee: Wallace & Tiernan Co Inc
Current assignee: Wallace & Tiernan Co Inc; Wallace & Tiernan Company Inc
Priority date: 1928-03-08
Filing date: 1928-03-08
Publication date: 1931-11-10
Anticipated expiration: 1948-11-10
Also published as: GB307473A

Description

Nov. 10, 1931.

G. D. PEET GAS SUPPLY APPARATUS Filed March 8, 1928 4 Sheets-Sheet l T INVE-NTOR 3 114 #1".

1 ATTORNEY Nov. 10, 1931 G. D. PEET 1,331,319

GAS SUPPLY APPARATUS Filed March 8. 1928 4 Sheets-Sheet 5 fill.

' INVENTOR WdM I} A; ATTORNEY i NOV. 10, 1931., G FEET 1,831,319

GAS SUPPLY APPARATUVS Filed March 8. 1928 4 Sheets-Sheet 4 I- I u INVENTOR Z0 2 M .w w

A; ATTORNEY Patented Nov. 10, 1931 UNITED STATES J PATENT? OFFICE ennui) n. PEET, or MONTCLAIR, new JERSEY, ASSIGNOR, TO WALLACE a Harman conrnnv, me, or BELLEVILLE, new JERSEY, A conroim'rron' or new Yoax ens SUPPLY nrrana'rps Application filed March a, 1928. Serial No. 260,117.

This invention relates to gas supply apparatus for supplying gas at a controlled rate. The invention has been made especially with the idea of providing an improved apparatus for withdrawing chlorine gas from a container holding a supply of chlorine under pressure, and for supplying the chlorine for the treatment of water, such as the water of city or town supplies or sewage or other watery liquids, at a controlled and measured rate which may readily be controlled. as desired, and which is not affected by the pressure of the source of supplyof the gas. The invention aims generally to provide such an apparatus which, while being accurate and reliable in operation, shall be compact and of comparatively simple and inexpensive construction. Among the objects of the invention are to prevent access of water or moisture to corrodible parts of the gas supply mechanism when the apparatus is shut down, to prevent back flow of water from the mixing aspirator into. the gas supply apparatus in case of stoppage in the discharge line or low operating water pressure, to provide for escape of unused chlorine through a suitable outlet in case of leak in the gas supply when shut down or in case of failure of the aspirator to draw while the gas is turned on, and to avoid difficulty I from the formation of hydratein the apparatus. Other objects and advantages of the invention will appear from thefollowing de-' scription.

Apparatus embodying the invention in the form now considered most desirable comprises means for supplying at a reduced pressure gaseous chlorine or other treating gas drawn from a source of supply under pressure to an adjustable control valvewhich provides a flow controlling orifice and from 'which the gas passes at a desired flow rate; a flow meter; a water aspirator or other suction device for drawing the gas from the flow meter and mixing it with water; means for maintaining a constant, preferably slightly negative, pressure on the suction side of the aspirator decharging "to the faspirator throat; an improved form of pulsating flow meter designed a the apparatus is shutdown; and means for relieving abnormal pressure or vacuum in the passage or space between the aspirator and the flow meterf Other features of the inyention will appear from the following descrip tion.-'

A full understanding of the invention can best be given by a description thereof in connection with a diagrammatic showing of an illustrative embodiment of the invention, and a modification thereof, and a detailed description of an approved form of ap aratus em bodying the various features of t e invention 1 in connection with drawin illustrating such an apparatus especially designed for supplying a solution of chlorine in water.

In the accompanying drawings:

Fig. 1 is a view of one side of the apparatus with parts shown in section; 1 .F'g. 2 is a sectional view taken on the line '75 2-2 of Fig. 3, looking from the left of Fig. 3 and from the right of Fig. 1;

Fig. 3 is a sectional view taken on the llne 33 .of Fig. 4;

Fig. 4 is a secvional line4-4ofFig.3; 1 Fig. 5 is an enlarged fragmentary sectional view through the center 0 the water aspirator and adjacent parts;

Fig. 6 is a smallerscale view in elevation, but with the lower part of the pedestal sectioned. of the complete apparatus viewed from the same directionas Fig. 1; Fig. 7 isa diagrammatic view of an apparams according to the invention as embodied in plan view takenon the to Figs. 11:06;

-. Fig. 8 is a view in elevation, looking from the left of Fig. 1- and showing the device as I provided with an auxiliary aspiraton provided for discharging unused chlorine in'so-'- '95 lution; termined by the negatlve head of a column mof water raised'by the aspirator and dis- Fig. 9 is aview with parts broken away. and parts in section, looking from the right of igu 8i i v i i i A i Fig.10 is a view of the apparatus as shown to p in Figs. 8 and 9 viewed from the right of Fig. 9, but with the casing partly broken away and partly sectioned and certain other parts in section;

Fig. 11 is a diagrammatic view of a part of the apparatus shown in Fig. 7, but with the addition of the auxiliary aspirator shown in Figs. 8, 9 and 10;

Referring first to Fig. 7, in the apparatus illustrated diagrammatically in this figure, whichrepresents an apparatus according to the invention intended especially for supplying a solution of chlorine gas in water to flowing water at a controlled rate, the chlorine gas, supplied from a tank of compressed liquefied chlorine or other source of supply under pressure, passes through a supply pipe 10 to an automatically acting pressure reducing and regulating valve 11 from which the gas is supplied at a constant. or substantially constant, pressure, most desirably substantially above atmosphere, to a control valve 12which serves as a flow-controlling orifice which is adjustable for regulating as desired the rate of flow of the gas. From the valve 12, the gas passesthrough pipe 13 to a flow meter 14 mounted within a chamber 15 into which the gas passes from the flow meter and from which the gas passes by pipe 16 to a suction chamber 17 from which it is drawn through a suction passage 18 by means of a water aspirator 20. The ga drawn into the aspirator throat is mixed witli in, the water flowing through the aspirator, and the solution thus formed is discharged through the solution discharge pipe 21. Usuallv the waterflowing through the aspirator and out through the discharge pipe 21 is a minor flow of water which is delivered to a main flow of water to be treated by the chlorine.

Water is'supplied to the

chambers

17 and 15 from a constant level tray or tank 25 through connecting

pipes

26 and 27 respectively. Water is supplied to the tank 25 through an inlet pipe 28 from the water supply pipe leading to the aspirator 20, and the supply of water to the tank is controlled by a valve 29 controlled by a float 30. In order to prevent any .water containing chlorine from having access to thevalve 29,the space within the tank is divided by a partition 31 which extends somewhat above the normal water level in the main part of the tank and provides a space within the tank into which the inlet pipe 28 discharges and from which Water flows over the partition into the main part of the tank. The tank is provided with.

an overflow outlet 32.

NVhenthe apparatus is not in operation, water supplied to the

chambers

17 and 15 from the constant level tank will stand at the same level as the water in the tank. Both chambers extend somewhat above this level to provide gas spaces in the upper portions of and goes'into solution the chambers. The intake end of the suction pipe 18 opens into the chamber 17 at a point which is most desirably a short distance, say for example, above this normal Water level. When the aspirator is in operation, the suction through the pipe 18. creates a partial vacuum in the suction chamber 17 and also in the meter chamber 15 which causes the water to rise in these chambers until the water in the chamber 17 comes to the level of the intake opening of the suction pipe 18 so that water may be drawn through the pipe 18 to satisfy the excess capacity of the aspirator. The aspirator should have a capacity somewhat in excess of that required to draw gas from the suction chamber at the rate determined by the control valve 12. Excess capacity of the aspirator is satisfied by water drawn from the chamber 17, and a negative pressure is maintained in the suction chamber which is determined by the negative head of the body or column of water in the chamber. This negative pressure is transmitted through the passage 16 to the meter chamber.

When. as in the construction illustrated, the gas is drawn by an aspirator or other suitable suction device from a suction chamberin which a constant pressure is maintained. the pressure reducing and regulating valve 11 may be of any suitable form for reducing the supply pressure of the gas and supplying it to the control valve at a suitable maintained pressure. I have illustrated, however, in Fig. 7, and when, as shown, a pulsating meter is connected in the passage between the control valve and the constant pressure suction chamber, it is desirable to use, a form of pressure reducing and regulating valve which is adapted to maintain a constant drop in pressure across the orifice of the control valve 12. and, therefore, a practically constant flow of gas for any setting of the control valve, ir: respective of such slight variations of the pressure on the discharge side of the valve as are caused by the meter, as well as variations in the'supply pressure of the gas. This compensating device is of a,form heretofore used and is described. for example. in patents of Charles F. Wallace,,Nos. 1.2853191 and 1.2855192. It comprises a diaphragm 40 forming a partition between two pressure chambers 41-and 42 and from which operatingconnection is madeto a valve 43 by which the'flow of gas from the'supplv pipe 10 into the chamber 41 is controlled. The diaphragm the difierential gas pressure acting on the 1 the machine is pulsation of water in diaphragm 40 to close the valve and the dif-.-

f erent1al spring pressure tending toopen the liable and accurate pressure reducing means for supplying the gas at the desired pressure to the flow-controlling orifice of the control valve, and may be usedto advantage'even when an ordinary automatically acting pressure reducing valve could be used.

When the machine is shut down and the gas supply shut off, absorption of gas remaining in the connection between the con trol valve and the meter tends to produce a negative pressure in the connecting passage by which water would be sucked back and reach and damage the control valve. In order to prevent this and permit the use'of a control valve of material which is corrodible by chlorine in the presence of water-there is provided a vacuum relief device adapted to admit air to the connecting passage 13 when the pressure in the passage is reduced below the normal operating pressure and before it reaches a point at which there would be danger of water being drawn back through the passage to the valve. This device, as shown, comprises a closed tubular chamber 45 from which connection is made through a pipe or passage 46 to the gas supplypas'sage 13- and which is provided with awater column tube 47 extending downward therein and open-at the bottom and open to the atmosphere at the top. A small body of water or other suitable liquid is contained in the chamber 45 suflicient to seal the end of the tube 47 against inflow of air under the suction of the slight negative pressure which may exist in the.

connecting passage 13 during normal operation of the apparatus. If, however, when shut down a greater degree of vacuum is produced in the passage 13 by absorption of chlorine gas by water inthe meter, then before this pressure reduction as become sufficient to suck up water from through the passage 13, thewater seal will be broken and air will be drawn in through the tube 47 chamber 45 and tube 46- to restore-the pressure in the passage 13.-

VVhen the apparatus is in operation, there is a' slight pulsation of pressure in the passage 13 due to the action-of the-pulsating meter 14, and this causes a corresponding a bell or enlarged chamber 48 is provided at sage 13 is the tube 47; but the tube 47 is of such height that, under ordinary as will be disoperating conditions, 'no

charged out through the tu e 47. To avoid loss of water from the tube 47 in event of a.

momentary extra pressure being developed in the passage 13, as, sudden adjustment of the control valve 12,

the upper end of thetube 47:

- In order to avoiddamage to the valve 12 by reason of moisture passing backward from the meter through the passage .13, the pasmade verysmall, -desirably only of suflicient cross-section to permit the flow of chlorine gas at the desired rate. A fine.

bore silver tube has been found suitable. This small bore passage, by preventing circulatory movement therein ofthe gas ,and of vapor from the meter, serves efiectually to protect the control valve from access of moisture without the use of a check valve in between the-meter and the control valve.

A pressure relief tube 50 leads from a point below the water level in the chamber 17 and extends upward to a gas and water separating chamber 51 from which a discharge pipe or line. 52 extends. the tube50 extends down to a point below the level at which the water stands when the aspirator is not operating, that is, below the water level of the constant level tank 25 ,a distance sufficient so that the end of the tube will be water sealed against the entrance of The loweropen end of for' example, by a gas from the suctionchamber at any presi sure which should occur in normal operation of the machine. If, however, there is a leak in the gas supply when the apparatus is shut down, or if, while the gas is still flowing, the aspirator fails to operate due to failure of water supply,or to too low operating pressure, or to stoppage of the aspiratoror of the discharge line, a gas pressure is built up in the suction chamber sufli'cient to force the water level down to the lower end of the tube 50, then the pressure will be relieved by the fiow of gas out through the relief tube; As the gas flows out through this tube, it will carry some water with it. This water, however, will be separated out from the gas in the chamber 51, the gas flowing on out through the pipe 52, and the water returning to the suction chamber through a water return pipe 53 whicheXtends downward from the sepa-.

rating chamber 51 to a point within the chamber 17' below the end of the relief tube. 50. y possible escape of unused chlorine into the building is thus avoided, and the gas escaping through the pipe 52 may be discharged to t ,e outside atmosphere at'any point desired. The rovision of the gas and water separating c amber avoids any possibility of water becoming trapped and freezing in theis supplied nected thereto, the tube 50 means for relieving any excess pressure which may be developed within the suction chamber or in parts of the apparatus conand its connected discharge pipe also serve as a vacuum relief device to admit air to relieve excess vacuum in the suction chamber which may result from the gas supply being shut off and the aspirator left operating if the water connection from the constant level tank to the suction chamber should be stopped.

The supply pipe 26, through which water from the constant level tank to maintain the desired level of water in the suction chamber, should be sufficiently large so that the frictional resistance to flow of water therethrough will be negligible and that there can be no such resistance to flow due to friction or air looking as would substantially increase the negative water head which determines the negative pressure maintained in the suction chamber, or result in the drawing-in of air through the relief tube 50,

The suction tube 18 should be small enough so that the velocity of the gas and air flowing through it under the action of the aspirator will be high, but large enough to have a capacity somewhat greater than that required for the passage of the total amount of gas delivered to the suction chamber when the apparatus is operating at its highest capacity. p

In order to avoid a rush of water from the aspirator back through the. suction passage 18 to the suction chamber in case the solution discharge line becomes clogged or in case the water supply for operating the aspirator fails, a check valve is provided on the suction side of the aspirator in the passage 18. This check valve is conveniently formed by a ball 55 within a small chamber 56 connected in the passage 18, the ball being adapted to close against a seat at the intake side of the chamber in the event of back fiow, and being held by a stop rod 57 in position to leave a clear flow-way through the chamber when the flow is in the right direction.

" The ball need not act to completely prevent back flow of water, but it issufiicient if it serves substantially to prevent back flow. The provision of this ball check valve, which is of simple construction. and inexpensive, makes it unnecessary to provide a check valve in the solution discharge line beyond the aspirator.

While any suitable form of flowmeter might be used for measuring the gas supplied by the apparatus, a hydraulic pulsating meter of the kind shown is well adapted for use in the apparatus, especially when mounted in a chamber containing a body of non-circulating water as shown. The meter shown, is of well known form and is described, for example, in

55 Patent No. 1,285,492, hereinbefore referred mailers to. It comprises a bell or casing 60, open at the bottom and having an inlet at the top connected to receive gas from the passage 13, and which has within it an inverted siphon formed by a down-flow tube 61 and an upflow tube 62 connected by a bend at their lower ends, the upper end of the tube 61 being opened to the interior of the bell, and the upper end of the tube 62 connecting to an opening through the upper wall of the bell. The bell is mounted within the chamber 15 in position to be submerged in the water in thechamber with its upper end below the water level.

' As the gas flows from the passage 13 into the meter bell, the water within the bell is depressed until the water level reaches the bend of the siphon, whereupon the gas blows the water out of the tube 62, and then flows out through the siphon, relieving the pressure on the water and permitting the water to rise againwithin the bell. The water then rises within the bell until it reaches the upper end of the tube 61 or until the gas pressure within the bell balances the water pressure, whereupon the gas again depresses the water and the operation is repeated.

The provision of means for supplying water from the constant level tank to the meter chamber is for the purpose of making for loss of water absorbed by the gas passing through the meter chamber so as to maintain the desired body of water in the chamber.

There is no circulation-of water through the chamber, however, and this results in the elimination of troublev from the formation of chlorine hydrate whereby the operation of the meter might be aifected. Since there is no circulation of water through the meter chamber, the water in the chamber assumes practically the room temperature.

If the water supply line from the constant level tank to the meter chamber were an open line providing for free flow of water, water would flow back and forth through the conwith the successive pulsations of the meter. This would result in fluctuations in the supply of gas, and a pumping of chlorine back into the'constant level tank. To avoid this, the connection between the constant level tank and the meter chamber is formed to limit the rate of flow of water to substantially prevent pressure pulsations in the meter chamber, while permitting a slow flow of water to the chamber sufficient to make up "for the loss of water to the gas passing through the chamber and maintain the supply of water within the chamber. Rather than to use a very fine bore connecting tube between the constant level tank and the meter chamber, I find it more desirable to use a pipe of sufiicient size so that it will not be apt to become clogged, and to restrict the flow-through the pipe by means of a disc 63 of porous and permeable necting pipe backflow under the material which is removably positioned at the inlet end" of the connecting pipe 27 within the tank 25. This flow restricting, or friction,

device, while permitting the passage of sufficientwater for maintaining the supply in the meter chamber, efiectuall prevents circulation between the meter c amber and the constant level tank, avoiding back flow of chlorine into the tank and insuring a steady flow of chlorine to the suction chamber.

. Provision for the discharge of unused chlorine to the outside atmosphere,'as described, is usuall satisfactory for taking care ofeall cases oi accidental building up of pressure within the suction chamber. When, however, the apparatus is'operated as a semiautomatic apparatus, the supply of water tothe aspirator being automatically cut off in well known manner whenever the flow of whereby such unused chlorine is drawn into an auxiliary minor flow of water to form a solution which may be discharged into a sewer or as desired. As here shown, an auxiliary water aspirator 65 is provided-from the throat of which a suction tube 66 leads into the suction chamber 17 and has its open inlet end located most desirably at about the normal, or shut-down, water level and lower than the operating water level withinthe chamber, so that when the main aspirator 20 is operating to supply a chlorine solution through the discharge line 21 no gas will be drawn through the suction tube 6 6. WVhen,

however, the main aspirator is not operating the, gas flowing into the suction chamber will,

by the action ofth'e-aspirator 65, be drawn out through the tube 66 and discharged through thedischarge pipe 67. When such an auxiliary suction device for taking ofi? unused chlorine is provided, it is still desirable to provide the apparatus with the pressure and vacuum relief tube and associated parts to 50 take care. of any possible accidental conditions which may occur in case otfailure of the auxiliary aspirator. v

. R ferring now to Figs. 1 to 6, these figures show an apparatus bu1lt to embody the in vention shown diagrammatically by Fig. 7. In describing the apparatus as illustrated in these views, the same numerals will, so 'far as possible, be used as are applied to corre-' sponding parts in the diagrammatic view.

The various operating" and connecting parts of the apparatus are mounted on or within ahead casing 100,-which.is set on a Y pedestal 101, as shown-by Fig. 6. The automatic pressure reducing and regulating. valve, or device, 11,1s mounted in a recess on water to be treated stops, and when the sup-.

There is illustrated in Fig. .11 a means the outside of one side of the head casing 100. The chlorine gas, supplied, as stated, from a tank of compressed liquefied chlorine or other source of supply under pressure, reaches the reducing valves through a supply pipe 10, and in supplied at reduced pressure to the control valve 12, andthen passes through a coiled pipe 13 to the flow meter. The pipe 13 connects through a stuifing box 102 with a passage in a block 103.

The block 103 is mounted on one side-of the'casing 100 and has depending therefrom a tubular transparent glass casing 104 which forms the meter chamber-' 15, a tubular casing 105 which is also most desirably of transparent glass which forms the suction chamber 17, and a tubular casing 106 also most desirably .of transparent glass which provides the chamber 45 of the vacuum relief device. The casing 104 is closed at its lower end by a block or cap 107 provided with an inlet opening to which is connected the pipe 27 leading from the constant level tank 25 and the casing 105 is closed. at its lower end by a cap or block 108 which has an inlet opening to which is connected the leading from the constant level tank 25. The prsating meter 14 is suspended within the chamber 15 by an upwardly extending tube or neck 110 which extends through a studing box gland 111 screwed into a threaded opening in the block 103 and connects at its upper end with an opening 112 to'which gas is delivered from the tube 13.

From the opening or passage 112, a passage 46 in the block 103 leads to a recess in. the under side of the block 103 in whichis pipe 26 Y secured a fitting 115 which carries the closed tube 106 and has an opening through which connection is made from the passage 112 to the interior of the tube or chamber 45. The

water column tube 47 extends through a ver- I tical opening in the block 103 and thiough the fitting 115 down into the chamber45 with its open lower end near the bottom of the chamber and sealed ,by water or other liquid in the bottom of'the chamber. ,The upper end of .thetube extends through a stufl'- ing box and gland 116, and has its upper end open to the atmosphere through an enlarged chamber 48, which serves to prevent loss of liquid from the tube 47 if theliquid is forced up through the tube by a sudden increase in pressure, as explained. The vacuumrelief device formed by the chamber 45 with its water column tube 47 is thus connected to V the gas passage between the control valve 12 and the flow meter.

From the meter chamber 15, the ga's'passes through a passage'16 in the block 103, indi cated by dotted lines in- Fig. 1, to the suction chamber 17." *(Ilhe suction passage (marked 18 on the diagrammaticview Fig. 7 through which gas and Water are drawn rom the suction chamber 17 to the water aspirator 20 is on a gasket 148.-

formed by a short tube which extends downward into the suction chamber and has its upper end entered in an opening in the block 103, a passage 121 formed in the block, and a connecting tube 122 which extends to the casing of the ball check valve through which connection is made to the aspirator 20.

Water for supplying the aspirator enters the apparatus through a supply pipe which extends up'through the pedestal 101 and leads to a shut off valve 131 from which the water passes into a chamber132, formed by a tubular casing 133 which is mounted on the side of the head casing 100. Mounted within the chamber 132 is a cylindrical strainer 134. The aspirator 20 is mounted on top of the casing 133, and the water reaches the aspirator through a tube 135 which extends downward within the strainer 134. Nater entering the chamber 132 thus passes through the strainer and then, entering the lower end of the tube 135, flows upwardly to the aspirator.

The aspirator comprises a small Venturi tube seated within a fitting 141 and held in place by a tubular fitting 142 which provides the outflow passage from the aspirator and most desirably forms part of the pressure-building discharge passage of the aspirator, and which is seated on a soft gasket 143 seated on the upper end of the Venturi tube and the upper end of the fitting 141. The fitting 142 is held pressed down by a nut 144 which screws into the upper end of a casing 145 which extends upward from the casing 133 and into which also the fitting 141 is screwed. The fitting 141 is provided with central passage into which the upper end of the tube 135 extends, and is seated on a gasket 146 resting on a flange 147. The Venturi tube 140 is seated at its lower end The seat for the'ball valve 55 is provided by a fitting 150, which is seated within a hollow boss 151 extending from the aspirator I casing 145, the fitting being held by means the forward movement of the ball 55 to preof a cap nut 152 which presses against a gasket 153 at the end, or the fitting and through which the end of the gas pipe 122 extends. From the chamber of the ball valve a passage leads through a fitting 155 to a closed space surrounding the throat of the aspirator from which the gas and water enter the asnirator throat through a series of openings located at or cross-section of the throat. the fitting 155 serves as a stop for limiting vent it from closing the passage when the flow is toward the aspirator.

The outflow passage fitting the discharge pipe through the head casing 100 and through thepedestal to theplace of application. A water pressure gauge is connected through 142 connects to just beyond the critical A rod 156 set in 21 which passes down pipe 161 to the water supply chamber 132 to indicate the pressure under which water is supplied to the aspirator. A' gas pressure gauge 162 is also provided connected to the gas supply through pipe 163 to indicate the 167 from which the water flows throughconnections 168 and 169 and is discharged into the tank on the inlet side oi; the tankpartition 31. The supply of water to the tank is controlled by a valve 29 which is controlled by a float 30 according to the level of water in the main compartment of the tank so as to maintain a constant water level in this compartment. The overflow outlet from the tank is shown at 32. v

In order to restrict the flow of water through the pipe 27. leading from the tank to the meter chamber and to prevent back flow from the meter chamber to thetank under the pulsations of the meter, aflow resistor 170 is provided, formed by a piece of porous and permeable material which is set in the outflow opening in the bottom of the tank to which the pipe 27 is connected, and which is removably held in position, as by means of a spring finger 171 as shown in Fig. 3. The flow resistor may thus be readily removed for cleaning.

The pressure relief tube .50 for relieving abnormal pressure which may develop in the suction chamber 17 as hereinbefore explained is mounted with its inlet end sufiiciently below the inlet opening of the suction tube 120 and extends upward through an opening in the gas and water separating chamber 51 which is formed by a casing 175 secured to the top of the block 103. The discharge pipe 52 leads from an outlet opening 176 in the wall of the casing 175. The water return tube 53 leads from the chamber 51 down through the block 103 and into the suction chamber to a point substantially below the lower end of the pressure relief tube 50.

The apparatus shown in Figs. 8, 9 and 10 is the same as that shown in Figs. 1 to 6 except for the provision of an auxiliary aspirat'or for withdrawing unused chlorine from the suction chamber 17 and causing it to be absorbed in an auxiliary minor flow of water to be discharged into a seweror as desired. As here shown, the auxiliary aspirator 65 receives its water through a connecting pipe 180 taking water from the strainer 167. n order that the operation of this aspirator shall not be affected by the cutting off of the water supply to the main aspirator 20, water isnot supplied to the strainer 167 from the suction tube 120, as explained in connection with Fig. 7 The discharge from the aspira-- tor 65 is by way of a connecting pipe 184 which connects to the discharge pipe 185 leading from the overflow\outlet 32 of the constant level tank.

The operation of the apparatus as shown in Figs. 1 to will be understood from the description in connection with Figs. 7 and 11.

Parts of the apparatus with which chlorine comes in contact will, as customary, be made of chlorine resistant material.

It will be seen that the apparatus is practically non-floodable, it being possible while the machine is in operation-to close the discharge line, or to shut off the water while the gas supply is on, or to shut off the gas supply While the aspirator is operating, without having chlorine gas escape into the room and without damage to the apparatus. It may be noted also that the only liquid which need be used in the apparatus is water, that the suction chamber and the meter chamber are automatically supplied. with water, and that the only place in the apparatus where Water is used and not automatically supplied is the vacuum relief device between the meter and the control valve. But the evaporation of water from this device is very slight, so that it is necessary to add water only at very infrequent intervals. The apparatus operates without trouble from the formation of chlorine hydrate. As pointed out, no hydrate forms in the meter chamber, and any hydrate which may form in the upper part of the suction chamber does not affect the operation of g the apparatus for thereason that the flow of fresh water into the suction tube melts the hydrate adjacent the entrance of the tube and keeps the tube open so that gas and water are sucked normally at all times. The high velocity of flow through the relatively short suction passage from thesuction chamber to the aspirator keeps this passage free from danger of hydrate clogging. Other advantages of the apparatus have been before pointed out. I

By the term volumetric flow meter.as

" used in the claims is meant a ineter which measures the amount of gas flowing by showing the passage of successive measured unit volumes of the gas, as distinguished from an orifice flow meter, such as shown in the Wallace Patent No. 1,514,919, for example, in which the rate of flow of the gas is measured by the drop in pressure across an orifice, and

in which an indication of the pressure drop across the orifice, or the pressure on on side of the orifice when the pressure on the other side is constant, shows the rate of flow of the gas, An orifice .flow meter measures and indicates the rate of continuous flow of the gas. A volumetric flow meter measures directly the number of unit volumes of gas passing, and shows the rate of flow by showing. the number of unit volumes passing through the meter per unit of time.

What is claimed is:

1. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice, pressure-reducing means for supplying the gas to the intake side of said orifice at a substantially constant pressure, a suction device, a gas passage leading from the. flow-controlling orifice to the suction deyice, means for maintaining a constant predetermined pressure on the suction side of the suction device, a flow meter connected in said passage, and means provldmg a normally rclosed air inlet to said passage between the flowscontrolling orifice and the flow meter formed to; admit air to said passage when the pressure therein is slightly below the normal operating pressure in said passage.

2. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice,pressure-reducing means for supplylng gas to the intake side of said orifice,

a suction device, a pasage leading from the flow-controlling orifice to the suction device,

means for maintaining a constant substantlally atmospheric pressure on the suction side of the suction device, aaflow meter connected in said passage, and means providing a normally liquid-sealed relief line connected -to said passage between the flow-controlling orifice and the flow meter formed to admit air to said passage when the pressure therein is slightly below the normal operating pressure.

3. Apparatus for supplying chlorine, comprising means forsupp ymg chlorine gas at approximately constant rate, a gas passage leading therefrom, a flow meter connected in said passage and containing liquidcapable of absorbing chlorine, and means providing a normally closed air inlet to said passage between the chlorine supply means and the flow meter formed to admit air to saidpassage when the pressure therein is slightly below the normal operating pressure, said passage being a closed passage-to which liquid has access only through themeter and from which there is no outlet between the meter and the gas supply means other than said air inlet.

4. Apparatus for supplying a treating gas, comprising means for supplying the gas at a substantially constant rate, a suction device, a passage leading from the supply means to the suctlon device, means for maintaining a predetermined pressure on the suction side of the suction device, a flow meter connected to said passage, and a water-sealed vacuum relief device connected to said passage be tween the supply means and the meter com prising a closed liquid-containing chamber and a fixed liquid column tube extending upward from below the liquid level in said chamber and leading to atmosphere.

5. Apparatus for supplying a treating gas, comprising gas supply means for supplying the gas, a passage leading from said supply means, a meter chamber, a pulsating volumetric flow meter submerged in liquid in said chamber and connected to receive gas from said passage and discharging into the chamber, a gas passage leading from said chamber, and means for maintaining in said chamber a non-circulating body of a liquid which is capable of being absorbed by the gas by feeding into the chamber just sufiicient liquid to make up for the liquid carried away by the gas passing through the meter, said chamber being closed except for the gas inlet and outlet and the liquid inlet.

. 6. Apparatus for supplying atreating gas,-

comprising gas supply means for supplying the gas, a passage leading from said supply means, a meter chamber, a pulsating volumetric fiow meter submerged in water in said chamber and connected to receive gas from said passage and discharging into the chamber, a gas passage leading from said chamher, a source of supply of water under a constant head, and a supply connection from the source of suppl to the chamber, said chamber being close except for the gas inlet and outlet and the liquid inlet.

,7. The combination of a closed chamber having a gas outlet, a pulsating volumetric flow meter submerged in water in the chamber and which discharges into the chamber, a source of supply of water under a constant head, and a supply connection from the source of supply to the chamber to maintain water in the chamber to a level below the outlet corresponding to said constant head,

gas, comprising means providing a flow-consaidconnection being formed to substantially prevent back flow of water therethrou h.

8. The combination of a closed chamber having a gas outlet,'a pulsatin volumetric flow meter submerged in water in the chamber and which discharges into the chamber, a constant level water sup ly tank, a connecting passage leading from t e tank to the chamber to maintain water in the chamber to a le el below the gas outletcorrespon'ding to said constant level, and a flow resistor for preventing back flow through said passage formed by a removable piece of porous and permeable material. 7

9. The combination of, a closedchamber a pulsating volumetric flow meter submerged in liquid 1n said chamber,

and means for .maintaining a non-circulating body of liqcarried away by the gas passing through the meter. v

in water in the chamber and which discharges into the chamber, means for supplying gas at a controlled rate to said meter, means for drawing gas from said chamber and main- 10. The combination of a closed chamber, a pulsating volumetric flow-meter submerged taining a slightly negative pressure therein,

a constant-level Water-supply tank, a supply connection from the tank to said chamber for maintaining water in the chamber to a level below the outlet determined by the tank level and the negative gas pressure in the chamber, and means to substantially prevent back-fiow of water through said supply connection.

11. Apparatus for supplying a treating gas, comprising means providing a flowcontrolling orifice, a pressure-reducing valve for supplying the gas to the intake side of said orifice at a pressure substantially above atmosphere and for maintaining a constant drop in pressure across the orifice under variation in pressure on the discharge side of the orifice, a suction device, a passage leading from the flow-controlling orifice to the suction device, a volumetric fiow meter connected in said passages, and means beyond said meter for maintaining a constant substantially atmospheric pressure on the suction side of the suction device.

12. Apparatus for supplying a treating gas, comprising means providing a fiow-controlling orifice, means for supplying the gas to the intake side of said orifice at a pressure substantially above atmosphere, a suction device, a passage leading from the flow-controlling orifice to the suction device, a volumetric fiow meter connected in said passage, and means beyond said meter for maintaining a constant slightly negative pressure on the suction side of the suction device.

v13. Apparatus for supplying a treating trolling orifice, a pressure-reducing valve for supplying the gas to the intake side of said orifice at a pressure substantially above athead of a'column of water raised by the suc-' tion of the aspirator. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice, a pressure-reducing valve for supplylng gas to the intake side of said orifice at a pressure sustantially above atmosphere, a water aspirator, a gas passage leadng from the flow-controlled orifice to the aspirator, a volumetric flow meter connected in said passage, meansbeyond said meter for maintaining a constant slightly negative pressure on the suction side of the aspirator determined by the negative head of a column of water raised by the suction of the aspirator, and adjusting means for varying the rate at which the gas is supplied by the apparatus by Varying the pressure at which the gas is supplied to the flow-controlling orifice.

15. Apparatus for supplying a treating gas, comprising means providing allow-controlling orifice, means for supplying gas to the intake side of said orifice at a substantially constant pressure, a constant pressure chamber to which the gas is delivered from the flow-controlling orifice, a volumetric flow meter connected between the fiow-controlling orifice and said chamber, a source of supply of liquid under constant pressure, a constantly open passage leading from said source to said chamber for maintaining a body of liquid in said chamber, a suction device for drawing gas from said chamber, and a pressure relief passage leading from a point within the chamber beneath the normal operating liquid level and having a discharge opening outside the chamber above thenormal liquid level whereby gas will be permitted to escape from the chamber when the pressure rises above a predetermined pressure. I

16. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice, means for supplying as to the intake side of said orifice at. a su stantially constant pressure, a suction device, a

passage leading from the flow-controlling .orifice to the suction device, means ,for maintaining a substantially constant pressure on the suction side of the suction device comprising a water column tube connected in said passage, and a pressure relief passage leading from a point within the water column tube beneath the normal operating water level and having an outside discharge opening above the normal water level through which gas will be permitted to escape when the pressure on the suction side of the suction device exceeds a predetermined pressure.

17. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice, means for supplying gas to the intake side of said orifice at a substantially constant pressure, a water aspirator,'a

passage leading from the flow-controlling orifice to the aspirator, means for maintaining a substantially constant negative pressure on the suction side of the aspirator, comsaid chamber back into the water column I tube.

18. Apparatus for supplying a treating gas, comprising means providing a flowcontrolling orifice, means for supplying gas to the intake side of said orifice, a water aspirator, a suction chamber, a passage leading from the flow-controlling orifice to the suction chamber, a suction passage leading from the suction chamber to the aspirator, a

source of supply of water connected to supply water to the suction chamber under a constant head, and a relief tube extending from a point within the suction chamber at a level below the intake end of the suction assage upward through the to of the cham er.

19. Apparatus for supp ying a treating a gas, comprising means provlding a flow-controlling orifice, means for supplying gas to the intake side of said orifice, a water aspirator and a suction chamber, a passage leading from the flow-controlling orifice to v the suction chamber, a suction passage leading from the suction chamber to theaspirator, a source of supply of water connectedto supply water to the suction chamber under a constant head, a relief tube extendmg from a point'within the chamber below the intake end of the suction passage upward through the top of the chamber, a separatlng chamber into which said relief tube discharges, and a water-return tube leading from the separating chamber to a point within the suctron chamber below the intake end of the rehef tube. A

20. Apparatus for supplying a treatmg gas, comprising means providin a flow-con.- trolling orifice, means for supp ymg gas to the intake side of the orifice, a water aspira- .tor, a suction chamber, a passage leadmg from the flow-controlling orifice to the suc- 'tion chamber, a suctionpassageleadmg from the suction chamber to the aspirator, means gas, comprising'means providing a flow-controlling orifice, means for supplying gas to the intake side of the orifice, a water aspirator, from the flow-controlling orifice to the suction chamber, a suction passage leading from the suction chamber to the aspirator, and means for supplying water under a constant head to the suction chamber and for permitting outflow of excess Water.

22. Apparatus for supplying a treating gas, comprising means providing a flow-controlling orifice, means for supplying gas to the intake side of said orifice, a water aspirator, a suction chamber, a passage leading from the flow-controlling orifice to the suction chamber, a suction passage leading from the suction chamber to the aspirator, a source of supply of water to supply Water to the suction chamber under a constant head, an auxiliary Water aspirator, a suction passage leading to the auxiliary aspirator from a point Within the suction chamber at a levelv below the intake end of the first said suction assage, and a discharge passage leading rom the auxiliary aspirator.

In'testimony whereof I have hereunto set my hand.

GERALD D. PEET.

a suction chamber, a passage leading