US2626627A

US2626627A - Apparatus for automatically proportioning pulp stocks

Info

Publication number: US2626627A
Application number: US204202A
Authority: US
Inventors: Werner D Jung; Carleton E Saecker
Original assignee: Allied Chemical and Dye Corp
Current assignee: Allied Corp
Priority date: 1951-01-03
Filing date: 1951-01-03
Publication date: 1953-01-27
Anticipated expiration: 1970-01-27

Description

Jan. 27, 1953 W. D. JUNG EI'AL APPARATUS FOR AUTOMATICALLY PROPORTIONING PULP STOCKS Filed Jan. 3, 1951 4 Sheets-Sheet l l ll ATTORNEY.

7 fink 2 2 t m K m 6 e c l E 8 OGE N 2 s N S 6 U o a s E T 2 t V T w W D N A m Rm A 4 9 E L W C Y B Jan. 27, 1953 w D JUNG ETAL APPARATUS FOR AUTOMATICALLY PROPORTIONING PULP STOCKS Flled Jan 3, 1951 Jan. 27, 1953 w. D. JUNG ETAL APPARATUS FOR RUTZJMATICALLY PROPORTIONING PULP STOCKS 4 Sheets Sheet 5 Filed Jan. 3, 1951 ATTORNEY."-

Jan. 27, 1953 w. D. JUNG EI'AL 2,626.627

APPARATUS FOR AUTOMATICALLY PROPORTIONING PULP STOCKS Filed Jan. 3, 1951 4 Sheets-Sheet 4 FIG.9.

REFINING [2a ENGINE INVENTORS. WERNER D. JUNG CARLETON E.SAECKER ATTORNEY.

Patented Jan. 27, 1 953 APPARATUS. FOR. AUTOMATICALLY PRO- PORTIONING PULP STOCKS Werner D. Jung, Tafton, Pa., and Carleton E. S'aecker, Teaneck Township, Bergen County; N. J assignors to Allied Chemicalz' DyeCorporation, New York, N. Y., a corporation olNew York Application January 3, 1951, Serial No. 204,202

8 Claims. 11

This invention relates. to a paper pulp stock control and proportioning system, and more particularly to such a system adapted for automatically controlling the volume of flow of a plurality of such stocks in predetermined ratiosto a paper forming machine.

Paper making furnishes are. often, composed of a plurality of pulp stocks. of different types of fibres, used in predetermined specified proportions depending on the final characteristics desired in the finished paper.

In order to achieve uniformity in the desired characteristics of the finished paper in such cases the proportions of the. several stocks must be maintained constant in their predetermined ratios.

Stock proportioning systems used in the past have been either entirely manually operated or have employed mechanical devices such as rotary vane or bucket type displacement meters, or, more recently, have employed various arrangements of rotameter type metering devices for example having a float within a vertical portion of the pipe line, with a relatively small annular space or orifice around the float through which the flowing stock material must pass. The flow through such devices was indicated or recorded on standard controllers which in turn actuated valves such as butterfly or damper typevalves in advance of the flow measuring devices in accordance with the indicated or recorded flowratesthrough the metering devices, thevalve control being effected by well known electrical or pneumatic means.

While certain of these prior art regulating mechanisms may operatesatisfactorily in proportioningchemical solutions and finepaper pulp stocks, all are subject to serious disadvantages when used withcoarse paper pulp stocks or fast draining stocks such as are often used in the furnishes employed in manufacturing paper board, roofing felt and .the like, employing, for example, coarse rag stock, steam defibered .wood, coarse waste paper, coarse broke, etc., which tend to pile up and plug the metering devices.

In such operations manual control of valves makes for fluctuations introduced by the human element particularly in themanipulation of such valves to relieve plugging. Any device involving a rotary element is subject to entanglement. by rag fragments or other debris which not only may impair its operation but may render it completely inoperative. Mechanical devices such as r0.- tameters result in periodic plugging caused either by the failure of the. devices to pass portions of the flow of stock" through the plugged device thus upsetting stockproportions to the paper machines and demanding the continual attention of an attendant to remove stoppages and restore the system to its intended mode of operation.

Positivemetering devices. such as those of paddle or bucket type, require an extravagantly large andcomplex, assembly and entail high installation and maintenance costs.

It is an object of the present invention to provide a completely automaticv multiple stock metering and proportioning systemwhich avoids the.

difficulties of prior art systems.

It isa further object of the invention to provide such a system which is free from plugging difiiculties even when used toproportion coarse pulp stocks of the character used in'the manufacture of roofing felts.

It is a. still further object of the invention to provide. such a system in which free and unrestricted flow of the several stocksis assured even when stocks of highly irregular composition and occasionally containing relatively large pieces of debris orundefibered fibrous'raw material are involved. I

It is a. still further object of the invention to provide such asystemin which the ratio of each stock to the. total is--separately metered and controlled.

A still further object of the invention is to provide such a; system in which the predetermined quantity of each of a plurality of stocks may be regulated proportionately only to the total stock flow, or in which one'master stock may be regulated by a level transmitter and the remaining stocks proportionately controlled through the flow of the master stock.

These and other objects are accomplished according to our invention by the automatic stock metering, and proportioning system or arrangement illustrated. in the. drawings, wherein like characters designate like parts throughout.

In the drawings, Fig. 1 illustrates schematicallyone modificationof theautomatic pulp control and proportioning system of our invention in which the proportion of each of a plurality of stocks is controlled independently of every other stock and dependently only on the total stock flow. Fig. 2 illustrates another modification of the system in which theflowof one of the stocks regulated 'byi thex'total. stockx'fi'ow acts to control the flow'of all the other stocks; Fig. 3 is a-planview' ofoneamodification of "an open channel flurne which. may be used in the system.- Fig. 4isa vertical section taken along;line 4.4 of Fig. 3. Fig. 5' illustratesaplan view and Fig. 6 a vertical section along; line fi.'-.=6 of Fig; 5, respectively, of another modification of Y open channel fiume whichmaybe used'in the system. Fig. 7 illustratesfa'plan-viewand Fig. 8 a vertical section along line 8--8 of Fig. 7, respectively, of still another modification of flume suitable for use in the system. Figure 9 illustrates a modification of the system in which total stock flow is measured at a common flume in which all the stocks are commingled.

Referring to the drawings, numeral til (Fig. 1) represents a mixed stock chest in. which all the stocks are commingled, the stock level of which is a measure of the total flow of the several stocks. Numeral ll represents a conventional recording level transmitter measuring the level of pulp in the mixed stock chest as by means of conventional compressed air bubbler pipe l2 supplied with compressed air from conventional compressed air measuring device [3 connected to an air source, not shown. Thus when compressed air is passed at a standard rate through air metering device 13 into tube [2 dipping below the surface of the commingled stock, the back pressure communicated through pneumatic tube 4 to recording level transmitter H is determined by the height of the stock above the bubble tube tip, so that this pressure furnishes a measure of the level of commingled pulp in the stock chest. Such measurement is transmitted through line M to the primary pens 15a of the several conventional ratio controllers 15, which measure and control the flow of each of the several stocks in a predetermined ratio to the whole in proportion matically actuated through air lines 2| controlled by the secondary pens I 5b of controllers l5, to regulate flow of stocks through

lines

22 and 22 into common line 23, thence through refining engine 24 if desired, to stock chest I and eventually to the paper machines, not shown.

Lines

22, 22 and 23 are not drawn to scale, but for simplicity of illustration, are shown much reduced in size. In practice, they must be large enough to avoid any standing head of liquid in the downstream sections 38 of the fiumes.

In the modification shown in Fig. 2, recording level controller H controls the flow of only a single pulp through line Ma, for example that flowing through open channel fiume Ida. The rate of flow of thi pulp is recorded on master flow transmitter 25, which positions the primary pens la of recording ratio flow controllers 155 which in turn control and proportion the flow of the remaining stocks to the fiumes in a manner similar to that shown in Fig. 1.

In the drawings a stock chest is shown as a convenient location at which to measure the total flow of all the stocks through fluctuations in the stock level in the chest. If desired, however, the total flow measurement may be taken in any other convenient device or receptacle positioned at a point beyond which the several stocks have been commingled, and which provides a stock head or level responsive to total flow of the stocks. A particularly suitable device for this purpose is shown in Figure 9 and comprises a common fiume 40, similar in all essentials to the fiumes indicated in Figures 1-8 in the drawings, interposed at a convenient location ahead of the stock chest [0 and beyond the point where the several stocks are commingled in common line 23. In such case, compressed air bubbler pipe lZa is introduced below the commingled stock level in the device,

' for example in the upstream section of the common fiume 48 at the desired convenient location l'lc.

In Figs. 3 and 4, numeral represents a stilling chamber in advance of the fiume proper; 31 is a first portion of the upstream converging section having an upwardly inclined floor 32; 33 is a second portion of the upstream converging section having a level floor 34; 35 is the throat section of the home having a downwardly inclined floor 36 and parallel sides 31; and 38 is the downstream diverging section of the fiume, which drops away vertically in cross section through a pipe or chute, not shown, or, to a catch basin, not shown.

In Figs. 5 and 6, the characters illustrate the same features as shown in Figs. 3 and 4 with certain structural modifications, particularly rounded corners in the stilling chambers which are particularly effective in avoiding the accumulation of pockets of stagnant stock.

In Figs. 7 and 8, the same description applies except that the upstream section 33 converges to a throat 35 of minimum width, and then diverges at 38.

In operation, the several pulp stocks, which, in the preparation of roofing felt, for example, may be four stocks, such as rag stock, stream defibered wood pulp, waste paper and broke from the felt machine operations, are defibered in conventional manner, and are preferably adjusted to the desired predetermined consistency by conventional means before feeding them to the proportioning system. The several individual stock suspensions are then separately passed through valves 20 whose openings have been regulated according to the indicated. requirement for that stock. The stocks then flow through lines 22 and the respective open channel fiumes 56a, I61), |6c and Mid, where the head or level of each Stockis measured by air pressure type metering devices, for example, by bubbler tubes l8 located at any convenient position in the upstream portion of the flume, for example in the converging section as shown, and the air pressure measurement is transmitted in terms of rate of flow to the secondary indicators or pens [5b of meters l5, which record and correct for any deviations from the desired predetermined flow rate for that stock. From the open channel fiumes, the stocks may drop through a pipe or chute into a receiver such as a catch basin or pipe, and from thence flow through lines 22' to a common stock line comprising a receptacle such as a pipe23 for further mixing, and refining, if desired, as in Jordan engines, and a stock chest I0, and thence to the paper machine. The level of the commingled stock in the head producingdevice, such as stock chest I 0 or the common fiume 40 as described, is measured in terms of air pressure by bubbler tube l2 and this pressure value is transmitted through pneumatic tube 4| to, and recorded on level transmitter II and this level serves as an indicator of total stock requirements. These requirements are then transmitted to the primary indicators or pens [5a of the individual controllers l5, which are coordinated with secondary pens l5b through a. ratio mechanism fixed at a predetermined desired sete Sec ndar pens liocont olwthe actuation of va ves. 210. i accordan ethe. posit o the pens. as e ulated b he f1 ...r dins hrou h. the. fiumes. b we l k own mea s. or xamn a lectrical-moi pn uma ical y, and; cheese the sizeof he openings; thro gh the. va s. crease or decrease he flowo he lames as e-- quired;

Flow C ntrol of th several stock m y. preferably be. ef ected.v independ ntly of: ea h. o her as, i -u tratedin Fig. 1, in. which case each stock. s. controlled. throu indi... dual. subo dina e ontroll rs whose p mary indi ators are: each d vidual y. ac uated. by the. p. d ne evel. r sm ttera tin as the. master con roller. r it: may be. ef c ed y f r t re ulatin any one s n le. to k throu h; the. e ording level trans-- m tten an us n the. rate of tom of this. stock;- as c mmunicated to a mast r. controllerito. r eulatethe; low o he, rema nin sto ks. through. th r subordi a e. c trollers. in accordance. w th th flow o f e. si le. pulp, asillu -trated in. Fig. 2.

Ijhe proportionine; system of: our invention provides unobstructed flow; for all. the. stocks; being free from devices such as orifices, weirs; buckets, floats or other restrictions which might. end o ause. dewaterina. plu ng. Q- rr uar iesinthe. flow.- o O The use of open channel flumes, especially w en used in, conjunctionwith com essed air, bnbbler tube, type metering devices and open flow: type control. valves, obviates. the. necessity for restrictive devices, andthe. combination of these features with the. conventional: automatic controller devices described, in the, arrangement specified, isthe, cr-uxofour invention.

The open channel: flumes. used in the. novel combination of our. invention are of the. type comprising a, laterally. convergingsection leadin .0. a. constricted: throat-1 section which may have parallel side as.- shown in Figs. 3; and 5, or the throat section mayconverge to, and diverge from, a. line of'minimum. width as indicated in Fig; 7... A stilling chamber orstock accumulator positioned. in.v advanceof the converging portion serves to. accumulateapool-of tock, and: thus smooth outtheflow-tothe flume and to .providea levelor head of stock respon Site; to variations. in rate of how through the throat-ofthe fiume, The floorofthe fiume maybe; upwardly inclined; in. the initial portion ofthe. converging sectionto assure readyflowofstock from the stilling chamber, then" maybe horizontal for the remaining-portion of theconverging section, is. downwardly inclined at the throat portion, i. e. the-section-ofg maximum; restriction and then. drops awayvertic ally. The

downward, inclination of the throat portion may begradual. for an appreciable-distance asshown in Figs. 3' and. 5, or maybean immediate vertical drop. as. shown in Fig. '7. The'co nstruction of the. fiume. beyond the throat portion" difiers in our system from that of conventional 'Venturiimposed. on the-pulp. afterit enters the throat the-precise. dimensions ofi the flumes are-not crit throaitoitha fiume;. i'. er hea zeri en mariroWorrestriction-l win he. d1esigned in accordancewith. engineering principles to. have dimensions appropriate for passing the. desired. quantity of stockper; unit of time, and? these. dimensions will be. coordinated with the, dimensions; of the. stilling chamber. to produce. an appropriate. variation. in. stock. level therein in. relation. tovariationsin rate. of flow. through. the. flume, toiproducerthe desired: sensitivity oi regulation thrQug-hthe controllers.

Variations; in. level of" the stock aremeasuredin the upstream portion of the; fiume, that: is, at. any convenient; location in advanceoffthethroat portion of the fiumesuchasin the stilling chamber or in the, converging section. of the flume tance. below the; level: or stockinv the. upstream portion of the fiumec The; pressureegenerated throug-hthehead of'stocks on the, air: or other gas remaining, in the. bubble. pipe. is transmitted to the. secondary. indicatorsof thencontrollers in a. mannerwell' known, to record changes in level or head in terms; of stock flowzthrough the-fiume,

and, if 'suchlevelsindioatea variation from the desired predetermined rateoihow; to bring about" changes in the: valve; settings toincrease or-dea crease the flow. of stock-in accordance .with such indicated pressure. Thedirect. measurement: of.

stock level; by means; of the: air: pressure type:

installation, is an important feature of our newcombination, asametering of zstockzby devices such as. depend on atakeeoft ofrstock from-the flurne through small orifices, or: the. like-,. is unsuitable due. to. they danger of clogging of the take-01f:

portion, and this head in turn depends notonly on the width of": throat: but: to: some extent also on the type of stock. andton its specificgravity; its consistency andritsfreeness. A- wider throat will, of course, pass alargervolume of'stock: than a narrow throat, and such dimensionssimay: be readily varied by one,-'skilled1ina thenartv to-adapt them to the requirements: of'gtheparticularsstock:

proportioning: system-.

By; way of: example; in the-preparation ofr'as roofing felt which; required the: furnishing of" four pulps ofthecharacter and'in-the amounts specified in the table below; itzwas: found that throat. dimensions. indicated in: thetable were suitable in flumes-of smooth surface. stainless steel construction.v having a stilling chamber ap-- proximately 1' l0"*wide by 3"- 5'" longby-Z' high" and a. converging section approximately 2' long;

TABLE -lume.= t r a men on su tablez. forvarious;

This: flow produced at head: in; the

stream. section. of: tha -flowr-and was coordinatedwith a controller instrument designed to record a head as 100% or maximum flow.

As used in the novel system of our invention, such fiumes may be of any suitable construction material such as wood, metal, concrete or the like, and should preferably be smooth so as to ofler as little frictional resistance to flow of pulp as possible. They may conveniently be positioned in one or more of the several pulp lines or ducts to measure and control its flow without restriction thereof.

The successful operation of the system containing the fiumes depends also on the provision of valves of the open flow type, that is, valves which in their fully open position provide a straight line, substantially unobstructed passage, and which in their various settings as regulated by the controllersin' accordance with indicated flow rates through the flumes, offer substantially no opportunity for clogging by heavy stocks. Such valves may be, for example, those of the pinch-clamp type or the well known alligator type valve equipped with a flat floor and a horizontal pivoted gate having its free end pointed downstream and adapted to be moved on its pivot upward to the top of the chamber to allow unrestricted fiow beneath it, or to be moved downwardly toward the floor of the chamber to restrict or cut oii the flow, or gate valves may be used if desired.

The recording level transmitter and the automatic ratio flow controllers are of standard conventional design of the' type commonly used in recording and controlling flow of fluids, as are the various connections, the air lines, piping, etc.

The automatic proportioning system of our invention not only provides a substantially foolproof system free from surges, plugging or stoppages but also furnishes a continuous record of the pulp composition of the finished paper at all times.

While the above describes the preferred embodiments of our invention, it will be understood that departures may be made therefrom within the scope of the specification and claims.

We claim:

1. An apparatus for automatically controlling the proportions of a plurality of paper pulp stocks fed from separate stock supplies through a common stock line to a paper-forming machine, which comprises aplurality of stock ducts leading from said supplies to said paper machine, a fiume having graduallyconverging side walls forming a restricted throat therein on each stock duct, an open fiow type valve on each du'ct ahead of said fiume, a valve control system, responsive to liquid level variation in a stock head producing device positioned in said common stock line, controlling the valve on at least one of said stock ducts to enlarge said valve opening upon fall of liquid level and reduce said valve opening upon rise of liquid level in said head producing device, and valve control systems responsive through air pressure type metering devices to liquid level variations at points ahead of the throats of a plurality of said fiumes controlling the valves ahead of the corresponding fiumes, the aforesaid valve control systems including a master controller and a plurality of subordinate controllers responsive to said master controller to vary the valve settings controlled by each subordinate controller in response to changes in liquid levels afiecting said master controller.

2., An apparatus for'automatically controlling the proportions of a plurality of paper pulp stocks.

fed from separate stock supplies to a single stock chest, which comprises a plurality of stock ducts leading from said supplies to said stock chest, a flume having gradually converging side walls forming a restricted throat therein on each stock duct, an open fiow type valve on each duct ahead of said fiume, a valve control system, responsive to liquid level variation in said stock chest, controlling the valve on at least one of said stock ducts to enlarge said valve opening upon fall of liquid level and reduce said valve opening upon rise of liquid level in said stock chest, and valve control systems responsive through air pressure type meterin devices to liquid level variations at points ahead of the throats of a plurality of said fiumes controlling the valves ahead of the corresponding fiumes, the aforesaid valve control systems including a master controller and a plurality of subordinate controller-s responsive to said master controller to vary the valve settings controlled by each subordinate controller in response to changes in liquid levels affecting said master controller.

3. The apparatus of claim 2 wherein said'stock duets lead from said flumes to a refiner and a stock duct leads from the refiner to the stock chest.

4. The apparatus of claim 3 wherein said plurality of said fiumes comprises at least all but one of the flumes.

5. The apparatus of claim 2 wherein the fiumes comprises a stock receiving stilling chamber, a laterally converging section having a horizontal floor, a constricted throat portion and a vertically disposed exit portion.

6. In an apparatus for automatically regulating the volume of flow of a plurality of paper pulp stocks in predetermined ratios, the combination of a mixed stock chest, a recording level transmitter measuring the level in said mixed stock chest, a series of ratio flow controllers having primary and secondary indicators, said primary indicators bein responsive to the level indicator of said recording level transmitter and being coordinated with said secondary indicators through a ratio mechanism fixed at a predetermined setting, a series of open flow type valves actuated by the said secondary indicators to change the size of the openings therein in accordance with the position of said indicators, a series of open channel fiumes having a con verging upstream section terminating in a restricted throat, connected to said valves, a series of air pressure type metering devices positioned in the upstream sections of said fiumes to measure the head in said, upstream sections, said metering devices bein connected with the respective ratio flow controllers to actuate the secondary indicators thereof in response to said upstream head in said flumes, pulp conveying lines connected with the outlets of said flumes to con- Vey the stocks therefrom, and a common receptacle for said stocks connected to the said mixed stock chest.

'7. In anapparatus for automatically regulatin the volume of flow of a plurality of paper pulp stocks in predetermined ratios, the combination of a mixed stock chest, a common open channel fiume havin a converging upstream section terminating in a restricted throat, a recording level transmitter measuring the level in the upstream section of said common fiume, a series of ratio flow controllers having primary and secondary indicators, said primary indicators being responsive to the level indicator of'said recording level transmitter and being coordinated with said secondary indicators through a ratio mechanism fixed at a predetermined setting, a series of open flow type valves actuated by the said secondary indicators to change the size of the openings therein in accordance with the position of said indicators, a series of individual open channel flumes having a converging upstream section terminating in a restricted throat, connected to said valves, a series of air pressure type metering devices positioned in the upstream sections of said flumes to measure the head in said upstream sections, said meterin devices being connected with the respective ratio flow controllers to actuate the secondary indicator-s thereof in response to said upstream head in said fiumes, pulp conveying lines connected with the outlets of said flumes to convey the stocks therefrom, and a common receptacle for said stocks connected to the said mixed stock chest.

8. In an apparatus for automatically regulating the volume of flow of a plurality of paper pulp 10 indicators being responsive to the indicated flow through said primary fiume, and being coordinated with said secondary indicators through a ratio mechanism fixed at a predetermined setting, a series of secondary open flow type valves actuated by said secondary indicators of said secondary ratio flow controllers to change the size of the openings therein in accordance with the position of said indicators, a series of secondary open channel fiumes connected to said secondary valves, a series of air pressure type metering devices positioned in the upstream sections of said secondary flumes t measure the head in said upstream sections, said metering devices being connected with the respective secondary ratio flow controllers to actuate the secondary indicators thereof in response to said upstream head in said secondary flumes, pulp conveying lines connected with the outlets of said primary and said secondary flumes to convey the stocks therefrom and a common receptacle to said stocks connected to the said mixed stock chest.

WERNER D. JUNG. CARLE'ION E. SAECKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,357,760 Allen et al. Nov. 2, 1920 1,568,619 Phelps Jan. 5, 1926 1,936,538 Borden Nov. 21, 1933