WO2009131458A1

WO2009131458A1 - A method of pumping, a construction for a pump and applications thereof

Info

Publication number: WO2009131458A1
Application number: PCT/NO2008/000149
Authority: WO
Inventors: Svein Andersen; Carsten Andersen
Original assignee: Andca As
Priority date: 2008-04-25
Filing date: 2008-04-25
Publication date: 2009-10-29

Abstract

The invention concerns a method for pumping a mixture of relatively large particles and liquid, such as water, through an inlet (4) and through a pipe (11) in a careful manner with regard to the particles. The method uses a pumping device including an ejector pump, where a drive fluid is pumped into the pipe in the pump direction. The procedure is characterized by the fact that the drive fluid is led to an inlet nozzle (6) by relatively high pressure that is transformed to speed / negative pressure or suction in a deceleration chamber (8) arranged adjacent to the inlet (4), whereby there will be a negative pressure in relation to the pressure in the liquid / particle mix that flows into the inlet (4). When liquid from the liquid / particle mixture flows into the deceleration chamber (8) through drainage holes / slots (5) in the inlet (4), the drainage holes / slots (5) having smaller dimensions than the particles in the liquid, the liquid from the deceleration chamber is then brought together with the liquid / particle mix and transported in the pipe for further treatment. The invention also concerns a pump construction, and the applications of it.

Description

A METHOD OF PUMPING, A CONSTRUCTION FOR A PUMP AND APPLICATIONS THEREOF.

The present invention relates to a method for pumping a mixture of relatively large particles and a fluid, such as water, through an inlet funnel up to and in through a pipeline in a way that is gentle to the particles, where a pump is applied that functions according to the ejector principle where a drive fluid is pumped into the pipe approximately in the direction of the pumping as described in the ingress in the subsequent claim 1.

The invention also relates to a pump construction for bringing forward fluids mixed with relatively large particles which shall be carefully brought forward through a pipeline, where the pump comprises an ejector pump to pump fluid in to the pipe in the forward feeding direction for the particle/fluid mixture.

The invention also relates to applications of the pump construction.

The invention is associated with an ejector pump that can provide a gentle pumping of relatively large and fragile particles which are mixed with a fluid and which shall be pumped with the fluid. In more detail, the particles which are to be pumped can be marine organisms such as fish, smolt, salmon, shellfish and krill; or food materials in the form of fruit (apples, plums, berries such as cherries, morello cherries, blackcurrants, red currants, etc.), vegetables, eggs, poultry, etc.

The pumps that have hitherto dominated the market have either been based on centrifugal pumps with withdrawn impellors, channel pumps, positive displacement pumps or pumps that, in one way or another, use a vacuum.

But it is also known to use pumps that work according to the ejector principle to drive a mixture of water (generally a fluid) and particles forward through a main pipeline (a tube or a hose) up to the delivery location. These pumps function such that a drive fluid, normally water/seawater, is coupled or led at large pressure and high velocity into the ejector pump in the driving direction of the fluid/particle mixture.

The pump construction is, as a rule, integrated with the inlet of the main pipeline, but it is also used as a booster pump to increase the pressure to amplify the transportation of the fluid/particle mixture through the main pipeline by being connected a distance forward along the pipeline.

Such pumps can be used, for example, when fish in a net cage shall be transferred to the cargo hold of a vessel (or in a well boat) for further delivery. The inlet of the pump is immersed down in the net cage in a controlled manner, and when the pump for the drive water is started, the mixture of water and fish is conducted into the hose and further up into the cargo hold.

However, there is a considerable pressure difference between the inflowing drive water and the water/particle mixture it shall pump. At the coming together of these two fluid phases, the fish (or the particles) are subjected to considerable blows and knocks, something which leads to surface damages on the fish/particles which are being pumped. Such damages appear as bruises or cuts in the skin. Thus, the particles (fish or the like) are not handled gently when such pumps are being used.

For the supplier of the catch and the further steps in the distribution chain, such surface damages can have a considerable negative economic effect as the sale value of the fish is reduced.

Therefore, it is an aim of the invention to provide a construction of an ejector pump which will eliminate the above mentioned disadvantages of the previously known ejector pumps.

Furthermore, it is an aim of the invention to provide a construction of an ejector pump that may reduce the damages on the particles which are floated in a fluid which in turn is driven forward by a fluid which is delivered from a drive pump (drive water pump).

Consequently, with the invention one aims to improve the construction of an ejector pump. The method according to the invention is characterised in that the drive fluid is conducted up to an inlet nozzle with a relatively high pressure which is transformed to a speed/under-pressure or a suction in a deceleration chamber set up adjoining the inlet funnel, whereby an under-pressure is created in relation to the pressure in the fluid/particle mixture that flows into the funnel, in that fluid from the fluid/particle mixture being made to flow into the deceleration chamber through drainage holes/slits which are formed in the inlet funnel, said drainage holes/slits have smaller dimensions than the particles in the fluid, and thereafter the fluid from the deceleration chamber is blended with the fluid/particle mixture to be transported forward through the pipeline for further handling.

According to a preferred embodiment a conformed inlet funnel with drainage holes or slits is used which is dimensioned in area and number so that only a calculated amount of fluid is let through the holes or slits and no particles above a certain size can pass through.

According to another preferred embodiment a conical inlet funnel is used which is formed with a steadily decreasing flow cross section in the downstream direction, so that the fluid mixture which is pumped gets an accelerating (increasing) velocity down to the outlet as a consequence of the reduction being larger than the amount of fluid which is sucked out.

According to yet another preferred embodiment a deceleration chamber is used which has an increasing cross section so that the drive fluid gets a decelerating velocity towards an outlet nozzle through which the drive fluid and a part of the fluid that comes into the funnel is led up to the pipe.

According to yet another preferred embodiment, the energy transfer from the drive fluid, when specially sensitive products are being pumped, can take place over several steps (cf. the enclosed figure 4) where one, in addition to the nozzles, has built in an additional nozzle which sits in the outlet of a diffuser (the mixing step) and gives the pumped fluid mixture an extra supply of energy to overcome the loss in the delivery pipeline.

According to yet another preferred embodiment, the nozzle areas on one or more nozzles can be adjusted (regulated) in that by altering/replacing the nozzle mouthpiece and the spacer between the flange pair 15 and 16 so that the flow conditions between driving fluid and particle/fluid mixtures in the pumping device can be adjusted to several products with varying sensitivity.

The construction according to the invention is characterised in that the particle/fluid inlet comprises a conical inlet body with a converging cross-section in the downstream direction, and a deceleration chamber-forming coat surrounding the conical inlet nozzle, said deceleration chamber comprises: an inlet to which the drive fluid can be added in the direction of flow for the particle/fluid mixture, and also an outlet for bringing together the drive fluid with the particle/fluid mixture through the funnel, and the conical inlet body comprises drainage holes/openings which can let a part of the fluid from the particle/fluid mixture into the deceleration chamber during the pumping.

According to a preferred embodiment of the pump construction, the drainage holes/openings are dimensioned in area and number so that only a given amount of fluid is let through and no particles above a certain size can pass through.

According to another preferred embodiment the inlet funnel has a conical form with an evenly decreasing area so that the pumped fluid mixture gets an accelerating (increasing) velocity towards the outlet due to the area decrease being larger than the amount of fluid which is sucked out.

According to an additional preferred embodiment the deceleration chamber has an increasing cross-section so that the drive fluid gets a decelerating velocity towards the outlet nozzle.

According to yet another preferred embodiment the pump comprises an inlet for the drive fluid distributed over several steps (cf. the enclosed figure 4) where it, in addition to the nozzles, comprises a third nozzle which is set up at the outlet from the diffuser and gives the pumped fluid mixture an extra energy supply to overcome the pipe loss in the supply pipe.

According to yet another preferred embodiment the nozzle areas on one or more of the nozzles can be reset (regulated) by changing/replacing the nozzle mouthpiece and the spacer between the pair of flanges (15,16) so that the pump device can be adapted to several products. According to the invention the pump construction is preferably used integrated in a trawl for pumping a mixture of catch and water forward to a processing location and especially pumping of catch up to a trawler with the drive water for operation of the pump being delivered from a drive water pump which is placed onboard the trawler.

According to another preferred embodiment the pump construction and method are used according to the preceding claims for transport of food articles under preparation of such where water is applied as a transportation medium, as the articles of food can comprise of fruit (apples, plums, types of berries such as cherries, morello cherries, blackcurrants, red currants), vegetables, eggs, poultry or other products which need gentle treatment during storage and transport from producer to consumer.

The pump device which the fluid with particles goes through, has no moving parts, and by means of the new construction it is possible to control the fluid velocities and the dynamic forces the particles are subjected to such that one obtains a completely damage-free pumping of the particles without impact damages from guiding wanes and pumping wheels which is common in rotating pumps, or dynamic damage because of the high fluid velocities which are common in standard ejectors.

As a consequence of the possibility of obtaining pumping completely free of damage, the invention is very well suited to transfer by pumping of different types of fish and shellfish, such as from a net cage/trawl bag and up to a vessel for further transport and handling, or in other situations where pumping is necessary. Furthermore, different articles of food, such as vegetables, fruits and berries can be transported in a gentle way by being pumped in water. As is known, types of berries, such as morello cherries, cherries, plums and, to some extent, apples and pears, are very susceptible to being bruised during handling and transportation, something which can be completely eliminated by the use of the present invention.

The invention shall now be described in more detail with reference to the figures, where:

Figure 1 shows a vertical section of the pump construction according to the invention. Figure 2 shows a first alternative embodiment of the pump.

Figure 3 shows a second alternative embodiment of the pump.

Figure 4 shows a third alternative embodiment of the pump.

With reference to figure 1 , the outer sides and radially inwards to the centreline S of the pump which is shown, are constructed by an outer circular annular space- forming coat-part 2 which (seen in the figure) runs vertically downwards and is bent in an arch form in towards the centre S and upwards to form a conical inlet funnel 4. The funnel 4 which extends inwards inside the coat 2 has a conical shape so that it is gradually tapered in the downstream direction (i.e. in the pump direction, seen upwards in the figure). This means that at the inlet 40 of the funnel 4 there is a larger flow cross-section than at the outlet 42 from the funnel.

The conical funnel 4 is shaped with through-going openings 5 in the wall of the funnel so that a fluid connection can be set up between the inner flow volume of the funnel and the volume/space 8 which forms a deceleration chamber on the outside of the funnel. The openings 5 can comprise through-going bored holes, slits and the like arranged in a regular or irregular pattern through the conically shaped funnel wall. The lower section 29 which comprises the funnel body 4 can constitute a separate section which is connected to the rest of the coat construction 2 via the mutually adapted ring-formed flanges 31 a, 31b and which are sealed with the necessary ring gaskets. They can be fastened to each other with a screw connection. Thus, the section 29 with the funnel 4 is replaced according to need, so that the pump can be adjusted to the actual conditions.

The pipeline with which the pump is integrated, is shown by 11 and comprises a downwardly extending pipe 11 which is led over the inlet funnel 4, i.e. co-axially on the outside of this. The lower ring-forming edge 7A of the pipe 7 ends approximately where the conical body of the funnel 4 starts.

The pipe/pipeline 11 is shaped so that the lower edge 7A is positioned near the outer wall 44 of the funnel 4, thus to form a narrow ring-formed slit 6 between the pipe end 11 and the funnel. This slit makes up the first inlet nozzle 6 according to the invention so that the speed of the drive fluid increases to about 25-30 m/s. The bent pipe 11 is, viewed upwards, shaped straight up or gently curving outwards before it is angled radially inwards in such a way that the inner wall 11 B of the pipe is positioned relatively near the ring-formed top edge 4A of the inlet funnel 4, thus to form a second outlet nozzle 9 from a deceleration chamber 8, see the next paragraph.

The outside 41 and the inner wall 43 of the funnel define between themselves in the whole height extension of the funnel 4 a ring-formed chamber 8 (also called a deceleration chamber) to which the drive fluid flows in through the ring slit 6. This represents a volume expansion in the flow direction, which gives a decelerating fluid velocity of the drive water in the chamber 8. From the deceleration chamber the fluid flows further upwards and through the ring-formed outlet nozzle 9 and further into the pipeline 11.

With the help of the mutually adapted flanges 46 and 48, respectively, the downwardly extending pipe 11 and coat-part 2, respectively, are joined together so that an outer ring-formed drive fluid chamber 22 is formed. On diametrically opposite sides of the coat 2, hoses are connected, for example, two pieces at the inlets 25 and 27, respectively, for supply of drive fluid to the chamber 22. The fluid is delivered through the hose with the help of the drive water pump 50 as outlined in figure 2. The fluid fills the chamber and is driven further through the ring slit 6 between the foot of the funnel 4 and the lower edge of the pipeline 11.

Further upwards (downstream) the pipe 11 continues over in the main pipe or pipeline that leads further to the further handling of the fluid/particle mixture.

To adapt the pump device the nozzle areas, on one or more of said nozzles 6,9,10 can be reset (regulated) by changing/replacing the nozzle mouthpiece 7 and the spacer between the flange pair 15, 16, according to the figures 1 ,3 and 4, so that the pump device can be adapted to several products.

The function of the ejector pump according to the invention. The present invention will be comprised of the main pump (the ejector pump) as shown in figure 1 , alternatively in figure 4, and which the patent application concerns. An embodiment which also shows a standard drive water source/ drive water pump 50 which delivers drive fluid to the main pump of the invention appears in figure 2. The invention is consequently based on the main pump working according to the ejector principle. The ejector principle is a well known and much used pumping principle. However, gentle treatment of relatively large particles in the fluid with ejector pumping is a question of fluid velocity and also direction conditions between the sucking-in fluid mixture with particles and the drive fluid which is pumped into the inlet funnel 4 in the ejector with a relatively high pressure from the drive fluid source 50.

With the described pump device one takes into account the above mentioned problems and solves these in a new and original way. The pump in figure 1 and alternatively figure 4, is, as mentioned, comprised of one, preferably two, supply pipes (hoses) 22,24 for drive water 1 into the pump. The drive water is led down through the circular bucket-formed housing 2 up to the first inlet nozzle 6.

The particle/fluid mixture flows in through the circular inlet funnel 3 and goes over into the conformed inlet funnel 4.

The drive water 1 that enters into the first nozzle 6, between the inlet funnel 4 and the nozzle mouthpiece 7 is throttled and gets a relatively large fluid velocity through the first nozzle as a consequence of the pressure on the drive water and the small nozzle area that makes up the narrow ring-formed passage 6. In this way, an under-pressure (suction) arises in the deceleration chamber 8, parts of the water (fluid) in the inlet funnel 4 are sucked out through the small adapted holes/slits 5 in the wall of the inlet funnel 4.

At the same time, the fluid velocity decreases further in the deceleration chamber 8 because of the volume increase in the chamber, so that when the drive fluid (mixed with water that came in through the funnel) passes the second outlet nozzle 9, one can achieve a desired fluid velocity adjusted to the fluid velocity of the particle/fluid mixture at the outlet 42 from the inlet funnel 4. Thus, one achieves a damage-free energy transfer from the drive fluid.

The particle/fluid mixture, which has been sucked in through the conical funnel 4 has had a somewhat accelerating velocity since the area reduction gives a larger effect than the amount of liquid which is sucked out through the holes 5 in the funnel 4. Consequently, the particle/fluid stream through the outlet funnel 4 will be mixed with the drive fluid stream at the inlet of the diffuser 10 (mixing chamber) downstream of the funnel 4 in a gentle way as the velocity difference between the two streams is relatively low and the direction is in unison.

If one pumps a fluid mixture with very fragile particles the velocity of the streams should be in tune by a careful dimensioning of the pump and also the pressure of the drive water which is supplied to the deceleration chamber 8. The adaptation of the energy transfer from the drive fluid to the pumped medium can also be achieved by using three nozzles as shown in the solution example in figure 4, where one, in addition to the first and second nozzles, respectively, 6 and 9 respectively, which are positioned below the inlet of the drive water in the coat, has built in a third nozzle 14 which is positioned above the inlet of the drive water in the coat above the inlet. Thereby, some of the drive water (about 1/4) can be led forwards, via a throttling chip 13, up to the third nozzle 14 which sits in the outlet from the diffuser (where the fluid/particle mixture and the drive water are mixed into the pipeline 11) and gives the pumped fluid mixture an extra energy supply so that the pipe loss in the delivery pipe 11 can be overcome.

According to an example, such a pump according to the invention can be driven such that the drive fluid flows into the diffuser downstream of the funnel 4 with a speed of 7-8 m/s, while the fluid/particle mixture which flows up through the funnel 4 has a speed of 2-4 meters/second. The pump can be dimensioned and be driven such that, for example, a third part of the fluid that comes into the funnel 4 flows radially out to the chamber 8 and is mixed with the drive fluid.

In some cases, the particles in the fluid can have a tendency to get stuck in the drainage holes 5 through the wall of the conical inlet funnel 4, such that these get blocked. To avoid this, a conformed grid 12 through which fluid can flow is fitted coaxially inside the funnel at a distance from the inner wall 45 of the funnel 4, as shown in figure 3.

In this way, one can increase the distance between the inlet funnel 4 and the particles in the fluid that flows in through the funnel and the risk of blocking is eliminated. In general, the dimensioning of the parts of the pump construction must be adapted empirically to the fragile product (marine organism/fruit and other food materials) which the pump shall be used to pump.

A brief operating description of the pump according to the invention.

The ejector pump (main pump) is driven by one or two hydraulically driven drive water pumps with a variable number of revolutions. They can be placed either on land/in a boat or submerged arranged in the vicinity of the ejector pump itself. In a given situation, for example, two drive water pumps (standard centrifugal pumps) are used which each deliver 150 m³/h of drive water (seawater). The drive water comes in the ejector pump itself through the hoses 1. The speed of the drive water increases in the nozzles 6 to about 25-30 m/s, and as a consequence, an under-pressure/suction arises in the deceleration chamber 8. The suction in the deceleration chamber 8 leads to the fluid/particle mixture being sucked into the inlet of the ejector pumps. 2 x 150 m³/h of drive water fed to the ejector pump will approximately result in about 300 m³/h of the fluid/particle mixture being sucked into the ejector pump and being pumped together with the drive water through the delivery hose 11.

The fluid/particle mixture (about 300 m³/h) which is sucked into the inlet of the ejector pump will have an accelerating (increasing) speed due to the area decrease in the funnel 4 being larger than the amount of fluid which is sucked out of the drainage holes/slits 5. About 100 m³/h fluid (no particles) from the fluid/particle mixture will be sucked into the deceleration chamber 8. In the deceleration chamber 8 the mixture of 300 m³/h of drive water and 100 m³/h fluid give a total of 400 m³/h of fluid being led up to the nozzle 9 where the speed of the mixture out will be about 7-10 m/s. The 200 m³/h of fluid/particle mixture (all particles) that have streamed all the way through the cone 4 will, as known, get an accelerating (increasing) speed due to the area decrease in the funnel 4 being greater than the amount of fluid which is sucked out through the drainage holes/slits 5. The speed out of the funnel 4 will be about 2-3 m/s, where the fluid/particle mixture will mix with the drive water that has a speed of about 7-10 m/s. Here, the drive water will also form an under-pressure/suction in the outlet of the funnel/cone 4 and in the mixing chamber.

The direction of movement of the drive water and the fluid/particle mixture in the mixing chamber is in unison, and the speed difference is considerably reduced. After the mixing chamber and diffuser, the total amount (600 m Ih) will be transported through the delivery hose 11 at a velocity of about 2-3 m/s.

Claims

P A T E N T C L A I M S

1. Method for pumping a mixture of relatively large particles and a fluid, such as water, through an inlet funnel (4) up to and in through a pipeline (11) in a way that is gentle to the particles, where a pump is used which functions according to the ejector principle, where a drive fluid is pumped into the pipeline approximately in the direction of the pumping, characterised in that the drive fluid is led up to an inlet nozzle (6) at a relatively high pressure which is converted into speed/under- pressure or a suction in a deceleration chamber (8) set up adjoining the inlet funnel (4), whereupon an under-pressure is set up in relation to the pressure in the fluid/particle mixture that flows into the funnel (4), with fluid from the fluid/particle mixture being made to flow into the deceleration chamber (8) through drainage holes/slits (5) which are formed in the inlet funnel (4), said drainage holes/slits (5) having smaller dimensions than the particles in the fluid, and thereafter the fluid from the deceleration chamber is brought together with the fluid/particle mixture to be transported through the pipeline (11) for further treatment.

2. Method according to claim 1 , characterised in that a conformed inlet funnel (4) with drainage holes/slits (5) is used which is dimensioned in area and number so that only a calculated amount of fluid is let through the holes/slits and no particles above a certain size can get through.

3. Method according to claims 1-2, characterised in that a conically shaped inlet funnel (4) which is formed with an evenly decreasing flow cross-section in the downstream direction is used so that the pumped fluid mixture gets an accelerating (increasing) speed towards the outlet (10) because of the decrease in area being greater than the amount of fluid which is sucked out.

4. Method according to claims 1-3, characterised in that a deceleration chamber (8) which has an increasing cross-section is used so that the drive fluid gets a decelerating speed towards an outlet nozzle (9) through which drive fluid and a part of the fluid that comes into the funnel (4) are led up to the pipeline.

5. Method according to claims 1-4, characterised in that when particularly sensitive products are pumped, the energy transfer from the drive fluid can take place over several steps (fig.4), where one in addition to the nozzles (6) and (9) has built in a further nozzle (14) that sits in the outlet from the diffuser (the mixing step) and gives the pumped fluid mixture an extra energy supply to overcome the loss in the delivery pipeline.

6. Method according to claims 1-5, characterised in that the nozzle areas on one or more of the nozzles (6,9,14) can be adjusted (regulated) by altering/replacing the nozzle mouthpiece (7) and the spacer between the pair of flanges (15) and (16) so that the flow conditions between the drive fluid and particles/fluid mixtures in the pumping device can be adjusted to several products with varying sensitivity.

7. Pump construction for transport of fluids mixed with relatively large particles which shall be transported gently through a pipeline (11), where the pump comprises an ejector pump to pump fluid into the pipeline in the feeding direction for the particle/fluid mixture, characterised in that the inlet for the particle/fluid comprises a conical inlet body with a converging cross-section in the downstream direction, and a deceleration chamber-forming coat surrounds the conical inlet nozzle, said deceleration chamber (8) comprises: an inlet (6) to which the drive fluid can be supplied in the direction of flow for the particle/fluid mixture, and also an outlet (9) for bringing together the drive fluid and the particle/fluid mixture through the funnel (4), and the conical inlet body comprises drainage holes/slits (5) that can let a part of the fluid from the particle/fluid mixture into the deceleration chamber (8) during the pumping.

8. Pump construction according to claim 7, characterised in that the drainage holes/openings (5) are dimensioned in area and number so that only a certain amount of fluid is let through and no particles above a given size can get through.

9. Pump construction according to claims 7-8, characterised in that the inlet funnel (4) is formed as a cone with an evenly decreasing area so that the pumped fluid mixture gets an accelerating (increasing) speed towards the outlet because of the area decrease being greater than the amount of fluid which is sucked out.

10. Pump construction according to one of the claims 7-9, characterised in that the deceleration chamber (8) has an increasing cross-section so that the drive fluid gets a decelerating speed towards the outlet nozzle (9).

11. Pump construction according to one of the claims 7-10, characterised in that the pump comprises an inlet for drive fluid distributed over several steps (fig.4) where in addition to the nozzles (6, 9) it comprises a third nozzle (14) which is arranged in the outlet from the diffuser and gives the pumped fluid mixture an extra energy supply to overcome the pipe loss in the delivery pipeline.

12. Pump construction according to one of the claims 7-11 , characterised in that the nozzle area on one or more of the nozzles (6,9,10) can be reset (regulated) by altering/replacing the nozzle mouthpiece (7) and the spacer between the pair of flanges (15,16) so that the pump device can be adjusted to several products.

13. Application of pump construction according to the preceding claim integrated in a trawler for pumping of a mixture of catch and water to a processing location.

14. Application of pump construction according to claim 13 for pumping a mixture of catch to a trawler, with the drive water for operation of the pump being delivered by a drive water pump which is placed onboard the trawler or submersed as an integrated part of the trawl construction itself.

15. Application of pump construction and method according to the preceding claims for transport of food materials during processing of such where water is used as a transport medium, as the food material can comprise fruits (apples, plums, types of berries such as cherries, black cherries, blackcurrant, red currants, etc.), vegetables, eggs, poultry or other products that need gentle treatment during storage and transport from producer to consumer.