US3400983A

US3400983A - Slurry feed pump

Info

Publication number: US3400983A
Application number: US578083A
Authority: US
Inventors: Wessel De Wayne
Original assignee: ELGIN SOFTENER Inc
Current assignee: ELGIN SOFTENER Inc
Priority date: 1966-09-08
Filing date: 1966-09-08
Publication date: 1968-09-10
Anticipated expiration: 1985-09-10

Description

p 1968 DE WAYNE WESSEL 3,400,983

SLURRY FEED PUMP 3 Sheets-Sheet 1 Filed Sept.

SUCTION STROKE FIG! INVENTOR.

DE WAYNE WESSEL p 1968 DE WAYNE WESSEL.

SLURRY FEED PUMP Filed Sept.

3 Sheefcs-5heet 2 DISCHARGE STROKE INVENTOR. DE WAYNE WESSEL Sept- 1968 DE WAYNE WESSEL 3,400,983

SLURRY FEED PUMP Filed Sept. 8, 1966 3 Sheets-Sheet 5 INVENTOR- DE WAYNE WESSEL Atty.

United States Patent Oflice PatenteclSept. 10, 1968 3,400,983 SLURRY FEED PUMP De Wayne Wessel, Elgin, Ill., assignorto Elgin Softener, Inc, Elgin, Ill., a corporation of Illinois Filed Sept. 8, 1966, Ser. No. 578,083 13 Claims. (Cl. 302-44) ABSTRACT OF THE DISCLOSURE The present pump is used for pumping a liquid slurry of solid material like that of diatomaceous earth suspended in water passed through diatomite filters used in connection with swimming pools and other process application having similar requirements. Two conduits are connected to the slurry feed line at longitudinally spaced points with a rearwardly seating check valve therebetween and these conduits are conected to the discharge chamber of the pump at spaced points with a flow regulator in the first conduit that is responsive to pressure change therein to maintain a substantially constant flow despite changes in pressure in the conduit. The pump is equipped with specially designed snifter valves on the inlet and discharge side thereof designed to handle the very abrasive particles of diatomaceous earth without leakage in the event of any particles becoming lodged in the valves. A further conduit interconnects the first conduit with the inlet side of the pump so that a flushing valve in this further conduit, when opened during intervals while the pump is not operating, serves to flush out the suction pipe and pump and also the second conduit with fluid from the first conduit.

This invention relates to a new and improved slurry feed pump especially designed for pumping a liquid slurry of solid material, like diatomaceous earth, suspended in water, to diatomite filters used in connection with swimming pools and many other process applications, having similar requirements, the pump being adapted, however, for pumping various liquids.

As far as I am aware, there has not heretofore been any successful slurry feed pump available on the market, all being objectionable by reason of excessive wear on parts as well as the extreme likelihood of the diatomaceous earth settling out and consequently plugging the system. The pump of my invention overcomes these disadvantages and affords other important advantages inherent in its construction enabling successful use of diatomaceous earth.

The pumping of diatomaceous earth solution has presented a difficult problem with pump manufacturers for a long time, the reasons being:

(1) The material is very abrasive in solution and therefore causes considerable wear on ball and poppet valves and seats;

(2) Diatomaceous earth settles out of solution very quickly unless it is moved continuously at high velocity or with sufficient agitation;

(3) The structural form of a diatom cell is very porous and pumps of the ball check or poppet design will leak when diatoms lodge between the valve and seat, and

(4) The diatoms having been mined and sent through high temperature kilns are hardened and when trapped between a valve and its seat will inevitably cause wear on one or the other or both and cause the pump to fail.

The salient features of the present invention are:

(1) There is a continuous controlled flow of water from the discharge chamber of the pump to the feed line, so that there is no opportunity for settling out of diatomaceous material that could cause plugging of the line;

(2) There is one manual flush valve for complete flushing of the suction and discharge snifters, discharge chamber, suction chamber, and suction line all at one time;

(3) The snifters, two of which are used per pump, are a manufactured item available at low cost and easily replaceable without the use of any tools and requiring no adjustment and, being identical, there is no problem of keeping in stock separate discharge: and suction parts, and it goes without saying that these soft gum rubber parts eliminate the need for gaskets required with pumps using ball check valves or poppet check valves and all of the other problems that went with the use of metallic ball check or poppet type valves, the only minor thing incidental to their use being their positive action in closing which creates a slight water hammer or surge in the suction line while keeping the solution in motion to prevent the settling out of diatomaceous earth, but that slight Water hammer is not considered at all objectionable, and

(4) With this type valve means, meaning the snifters, heavier concentrations may be moved by virtue of the fact that these check valves can expand to allow solids in the liquid to pass through with the liquid instead of straining out, which is done with ball check or poppet type valves which create a restriction by reason of the limited space between the ball or poppet valve and seat.

The following advantages are obtained:

(1) The snifters for both suction or inlet and discharge or outlet being of soft gum rubber, what little abrasive action is attributable to the diatomaceous earth is practically negligable whereas with the other types of pumps which it was attempted to use heretofore (without success) when the capacity of these other pumps was increased the ball or poppet check valves usually remained the same and, therefore, the velocity across the seats was increased and that resulted in a corresponding increase in the cutting action of the abrasive solution, which ultimately resulted in pump failure, whereas, with the present construction, the snifters expand easily to handle the increased pump volume and permit more solution to pass and no additional wear is involved;

(2) When two materials, as in the metallic valve and seat, Work against an abrasive material, one or both will eventually show wear, whereas the soft gum rubber used in the snifters allows the diatoms to impress or mold themselves temporarily in the soft rubber when a snifter closes and be released again when the snifter is opened, without any harm being done to the snifter;

(3) Ball and poppet check valves are more or less limited to operation in a vertical position, whereas I have found that the snifter type check valves can be used in any position equally well;

(4) A ball check valve or poppet check valve will seat at a point of direct contact with the seat whereas with the snifters, there is the full length of the flattened discharge end of the snifter to serve as a seal and if any diatoms are trapped at any given point or points, these cannot prevent the sealing at other nearby points, and even if diatoms are trapped in the passage the full length, they will temporarily impress or mold themselves into the soft rubber sufficiently to enable the snifter to close and seal properly;

(5) The snifters being inherently under internal stress resiliently at the discharge end tending to close, the suction created by the pump diaphragm in the suction stroke pulls the solution through the inlet snifter, and thereafter on the discharge stroke of the pump diaphragm the solution is pushed through the discharge snifter;

(6) The snifters being self closing, there is no lost motion, as in a ball or poppet type check valve where some outside force is required to start the ball or poppet valve to move toward or away from its seat, thereby allowing a certain amount of back flow or leakage, that is not possible with the snifters, and

(7) Although the pump of my invention was designed primarily for operation with diatomaceous earth solution, it is obviously adapted for various other liquids, the present application being for nonplugging self-adjusting and self'adapting suction and discharge check valves, plus the method of complete and easy flushing of all parts that come in contact with the solution being pumped and where it is, therefore, most important to be certain of keeping all passages clear and clean, and thus avoid any possibility of eventual clogging.

The invention is illustrated in the accompanying drawings, in which:

FIGS. 1, 2, and 3 show my improved slurry feed pump connected between a solution tank and a fee-d line going to the filters, FIG. 1 illustrating by arrows the fiow in the suction stroke, FIG. 2 the discharge stroke, and FIG. 3 the flushing operation;

FIGS. 1A, 2A, and 3A are all end views of the slurry feed pump related to FIGS. 1, 2, and 3, respectively, the hand operable valve being closed in FIGS. 1A and 2A, but open in FIG. 3A;

FIG. 4 is a perspective view of one of the snifter or check valves before application to the pump head, and

FIG. 5 is a perspective view of the same snifter valve as it appears when applied to the pump head.

The same reference numerals are applied to corresponding parts throughout the views.

Referring for the present, to FIGS. 1 and 1A, and related FIGS. 4 and 5, the slurry feed pump of my invention is indicated generally by the reference numeral 6 as having a suction line 7 extending downwardly therefrom to the solution tank 8, and a discharge line 9 extending upwardly to the feed line 10, which, as indicated by the flow direction arrow 11, extends to the filters to which the slurry, for example, diatomaceous earth solution, is to be supplied for filtering the water in a swimming pool, for example. Other process applications require water similarly filtered. A lift-type check valve is indicated at 12 between the point 13 where the discharge line 9 is connected to pipe and the point 14 where a flushing line 15 extending to the discharge fitting 16 of the pump 6 is connected, but it should be understood that the length of pipe between the

points

13 and 14 may be long enough or it may include some fittings or valves that would serve the same purpose of providing a pressure drop between these

points

13 and 14, so that the check valve 12 would not be necessary. Manually

operable shutoff valves

17 and 18 are shown at the

points

13 and 14, respectively, controlling the flow between lines 9 and 15 and the feed line 10, both of these valves being closed temporarily whenever the slurry feed pump 6 is out of operation for any reason. A T fitting 19 attached to the discharge fitting 16 communicates with the discharge chamber 20 in said fitting through a Dole regulator 21 which contains a restricted central port 22 insuring a constant predetermined rate of flow from the flush line 15 into the chamber 20 regardless of changes in pressure. Thus, if pressure in line 15 increases, the port 22 closes a little automatically to compensate for this increase, and vice versa in the event of decrease in pressure. The line 15 is connected to one end of the T fitting 19, as seen in FIG. 1A, and there is an extension 23 from the other end of the T fitting 19 to a manually operable valve 24 connected to the inlet fitting 25 communicating with the through-bore 26 thereof through a cross-bore 27. Valve 24, as will soon appear, is closed during normal operation but is opened at intervals only during flushing of the slurry feed pump and its connecting lines, as illustrated in FIGS. 3 and 3A, to clear out any possible deposits of diatomaceous earth which, if allowed to collect, might eventually cause clogging of one or more of the lines in the system or one or more passag s in the pump 6.

The pump 6 is illustrated as of the diaphragm type, the diaphragm being indicated by the reference numeral 28 and operable by a reciprocating shaft 29 that is reciprocable in any suitable manner by an electric motor 30 to cause suction in the chamber 31 on the out stroke of the shaft 29, when slurry from the tank 8 is delivered through the suction line 7 through an inlet snifter valve 32 into the suction chamber 31, the outlet or discharge snifter valve 33 communicating with the suction chamber 31 through the passage 34 being closed in this operation while the slurry is pulled through the inlet snifter valve 32 into the suction chamber 31.

The

snifter valves

32 and 33 are identical, both being manufactured items readily available on the market at a low cost, each preferably made of soft gum rubber in the form of a tube that is normally flattened its full length, as indicated in FIG. 4, and under inherent internal stresses tending to maintain the flattened form, either end being spreadable, as indicated at 35 in FIG. 5, to fit tightly on a neck 36 like that provided on the intake fitting 25, a similar neck 36 being provided on the body of the pump head 37 for the other snifter valve 33. Whether a snifter extends horizontally, like the one shown at 32, or vertically, like that shown at 33, is immaterial; the operation is substantially the same in either position or in any other position of angularity or when directed up or down. The pump head 37 is fastened to the body 38 of the motor by screws 39, clamping the marginal edge portions of the diaphragm 28 therebetween, as indicated at 40, the diaphragm 28 forming a flexible wall on one side of the suction chamber 31.

A venturi 41 is provided in the discharge fitting 16 at the upper end of the discharge chamber 20 in longitudinal alignment with the outer end of the discharge snifter 33 so as to entrain the diatomacous earth slurry (which is incidentally an approximately 5% solution usually) with the water delivered from the line 15 to flow upwardly in the line 9 to the feed line 10, as indicated by the particulates D (for diatoms) illustrated in FIG. 2.

In operation, there is a continuous controlled flow of water from the discharge chamber 20 to the feed line 10, so that there is no opportunity for any settling out of the diatomaceous earth material that could eventually cause plugging of the line. On the suction stroke illustrated in FIG. 1, the diatomaceous earth slurry is pumped as shown by the arrows from the solution tank 8 through the suction line 7 into the suction chamber 31 as the diaphragm 28 moves outwardly or to the left, the slurry being pulled through the snifter 32, snifter 33 meanwhile being closed mainly by reason of its inherent tendency to close and also by reason of the drop in pressure in suction chamber 31. Then, on the discharge stroke, as diaphargm 28 moves inwardly or to the right, as seen in FIG. 2, snifter 32 closes mainly by reason of its inherent construction and also be reason of pressure buildup in chamber 31, so the charge of diatomaceous earth slurry pumped in on the previous stroke is discharged through the discharge snifter 33, being pushed through it, and the diatom particles D in this charge, as seen in FIG. 2, are entrained with the water flowing from line 15 into chamber 20 and out through line 9 to the feed line 10, whereby to carry these particles D to the filters to which the feed line is connected. This operation of alternating suction and discharge stroke goes on continuously in the operation of the motor 30, but, at stated intervals, the motor 30 may be shut off and the manually operable valve 24, that is normally closed, is opened, as shown in FIGS. 3 and 3A, to flush out the entire system, water under pressure being delivered through the inlet fixture 25 to not only flush out the two

snifters

32 and 33 along with the suction chamber 31 and discharge chamber 30, but also the suction line 7 at the same time, water meanwhile continuing to flow from the line 15 into the discharge chamber 20 and out through line 9 to the feed line 10. There is, therefore, a complete clearing out of all lines and chambers, as well as both snifters along with the rest, to make certain that there is no collection of any particles D of diatomaceous earth left anywhere. Hence, when the valve 24 is closed again and motor 30 set into operation again, there is every assurance of 100% efficient operation of the slurry feed pump 6. It is not necessary to repeat the seven advantages previously outlined other than to say that with this invention, I obtain non-plugging, self-adjusting, suction and discharge check valves, plus the novel method of completely flushing out of all parts of the system that come into contact with the solution being pumped, and, while the invention is particularly adapted for the specific purpose mentioned it is not limited to that use.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. In a slurry feed system comprising a slurry feed 'pipe of appreciable length through which liquid is adapted to flow in one direction, a container for slurry solution having a suction pipe extending upwardly therefrom, a first conduit extending downwardly from said slurry feed pipe at one point of its length for supplying liquid therefrom under a predetermined pressure, a second conduit extending upwardly to said slurry feed pipe at a point appreciably downstream relative to said first conduit to deliver to said feed pipe slurry solution pumped from said container mixed with liquid from the first conduit, and a power operable pump having an inlet port connected with said suction pipe, and a discharge port connected with said first and second conduits so as to entrain liquid from said first conduit with the slurry solution being delivered through said second conduit to said slurry feed pipe.

2. A slurry feed system as set forth in claim 1 including a check valve in said slurry feed pipe between said first and second conduits seating toward the connection with the first conduit.

3. A slurry feed system as set forth in claim 1 includ ing a Bow regulator in the first conduit responsive to pressure change therein to maintain a substantially constant flow despite changes in pressure in said conduit.

4. A slurry feed system as set forth in claim 1 including a check valve in said slurry feed pipe between said first and second conduits seating toward the connection with the first conduit, and a flow regulator in the first conduit responsive to pressure change therein to maintain a substantially constant flow despite changes in pressure in said conduit.

5. A slurry feed system as set forth in claim 1 wherein there are an outwardly closing check valve at the inlet port and an inwardly seating check valve at the discharge port, each of said check valves comprising a normally fiat resilient tube, whereby in the closing of said valves any solid particles in the slurry that may remain in the valves are retained harmlessly between the opposing fiat walls of the tube which conform to the particles while adjacent portions of said walls in full contact with each other provide a good sealing action.

6. A slurry feed system as set forth in claim 1 wherein there are an outwardly closing check valve at the inlet port and an inwardly seating check valve at the discharge port, one of said check valves comprising a normally flat resilient tube, whereby in the closing of said valve any solid particles in the slurry that may remain in the valve are retained harmlessly between the opposing fiat walls of the tube which conform to the particles while adjacent portions of said walls in full contact with each other provide a good sealing action.

7. A slurry feed system as set forth in claim 1 wherein the pump is of a pulsation type comprising a body having suction and discharge chambers in communication with said suction pipe and second conduit, respectively, a normally fiat tube of resilient material in each of said chambers, one controlling flow between the suction chamber and inlet port and closing outwardly, the other controlling flow between the two chambers and closing inwardly.

8. A slurry feed system as set forth in claim 1 wherein the pump is of a pulsation type comprising a body having suction and discharge chambers in communication with said suction pipe and second conduit, respectively, a check valve controlling flow between said chambers and seating inwardly, and a normally flat. tube of resilient material in the suction chamber controlling flow between the inlet port and the suction chamber and closing outwardly.

9. A slurry feed system as set forth in claim 1 wherein the pump'is of a pulsation type comprising a body having suction and discharge chambers in communication with said suction pipe and second conduit, respectively, a check valve controlling flow between the inlet port and the suction chamber and seating outwardly, and a fiat tube of resilient material in the discharge chamber controlling flow between said chambers and seating inwardly.

10. A slurry feed system as set forth in claim 1 including a further conduit interconnecting the first conduit with the suction pipe anl inlet port of said pump, and a flushing valve in said further conduit openable during intervals while the pump is not operating, whereby to flush out the suction pipe and pump and the second conduit with fluid from said first conduit.

11. A slurry feed system as set forth in claim 1 wherein there are an outwardly closing check valve at the inlet port and an inwardly seating check valve at the discharge port, each of said check valves comprising a normally fiat resilient tube, whereby in the closing of said valves any solid particles in the slurry that may remain in the valves are retained harmlessly between the opposing fiat walls of the tube which conform to the particles while adjacent portions of said walls in full contact with each other provide a good sealing action, there being a further conduit interconnecting the first conduit with the. suction pipe and inlet port of said pump, and a flushing valve in said further conduit openable during intervals while the pump is not operating, whereby to flush out both of said tubes together with the suction pipe and pump and the second conduit with fluid from said first conduit.

12. A slurry feed system as set forth in claim 1 wherein there are an outwardly closing check valve at the inlet port and an inwardly seating check valve at the discharge port, one of said check valves comprising a normally flat resilient tube, whereby in the closing of said valve any solid particles in the slurry that may remain in the valve are retained harmlessly between the opposing fiat walls of the tube which conform to the particles while adjacent portions of said walls in full contact with each other provide a good sealing action, there being a further conduit interconnecting the first conduit with the suction pipe and inlet port of said pump, and a flushing valve in said further conduit openable during intervals while the pump is not operating, whereby to flush out both of said check valves together with the suction pipe and pump and the second conduit with fluid from said first conduit.

13. A slurry feed system as set forth in claim 1 wherein the pump is of a pulsation type comprising a body having suction and discharge chambers in communication with said suction pipe and second conduit, respectively, a normally fiat tube of resilient material in each of said chambers, one controlling flow between the suction chamber and inlet port and closing outwardly, the other controlling flow between the two chambers and closing inwardly, there being a further conduit interconnecting the first conduit with the suction pipe and inlet port of said pump, and a flushing valve in said further conduit openable during intervals while the pump is not operating, whereby to flush out both of said tubes together with the suction 7 8 pipe and pump and the second conduit with fluid from 3,039,399 6/1962 Everett 103-228 said first conduit. 3,127,846 4/ 1964 Kerns 103-228 X References Cited FOREIGN PATENTS UNITED STATES PATENTS 5 489,760 10/ 1918 France.

2,986,098 5/1961 Trout et a] 103228 X ANDRES H. NIELSEN, Primary Examiner.

3,001,828 9/1961 Stadtlaender 302--14