Pump Apparatus

Abstract

A Pump consisting of a pressure vessel (50), an inlet nozzle (51), an ejector nozzle (52) by which vacuum and pressur are applied, and an outlet nozzle (53). The inlet and outlet nozzles (51, 52) are selectively closed by interconnected knife gate valves, operated in tandem by a pneumatic cylinder whereby when one valve is closed, the other is open an vice-versa. An ejector valve located in the ejector nozzle (52) alternately creates vacuum and generate air flow through the vessel (50). The air from the ejector is introduced into the discharge line after closure of the outlet valve.

Description

In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention and wherein:

FIGS. 1 to 4 are orthogonal views of a vacuum/pressure tank suitable for use in a first embodiment of the present invention;

FIGS. 5 to 7 are orthogonal views of a vacuum/pressure tank suitable for use in a second embodiment of the present invention;

FIG. 8 is a front view of the apparatus of FIGS. 5 to 7;

FIG. 9 is a discharge end perspective view of the apparatus of FIGS. 5 to 7; and

FIG. 10 is an opposite end perspective view of the apparatus of FIG. 9; and

FIGS. 11 to 13 are views of an alternative, vertical vacuum/pressure tank second embodiment of the present invention.

In the FIGS. 1 to 4, there is provided a pump with no moving parts if it is considered that during its operation nothing moves. Only when the cycle is change from suction to discharge are valves operated. The pump consists of a pressure vessel 50 with three openings or nozzles. Nozzle 51 is the inlet, where the product gets into the vessel during vacuum generation and is connected via a vacuum hose or pipe to a suction nozzle with an inlet knifegate valve in between.

Nozzle 52 is where the vacuum is generated and is connected directly to an ejector. Nozzle 53 is where the product, once the pressure vessel has been filled, is evacuated by the use of compressed air, via an outlet knifegate valve.

The inlet and outlet knifegate valves are mechanically operated in tandem by one pneumatic cylinder, whereby when one valve is closed, the other is open and vice-versa, meaning that when the cycle is suction the inlet valve is open and the discharge valve is closed. An ejector valve is located after the ejector is open allowing the ejector to create vacuum and generate air flow through the vessel. The air from the ejector is introduced into the discharge line after closure of the outlet valve, this air finishing the conveying of any product being left over inside during the previous discharge cycle and leaves a clean discharge line ready for the next blow.

When the cycle is in discharge the inlet knifegate valve is closed, the outlet knifegate valve is open and the ejector valve is closed. By closing the ejector valve the ejector does not function as such and diverts the compressed air into the vessel impelling the product out of it through the outlet valve.

Timers control the length of each cycle. These timers are pneumatically operated and need to be adjusted according to the properties and behaviour of the product to be transported.

The length of the suction cycle is determined by the product properties and distance from the suction nozzle to the pressure vessel. The greater the distance, the longer the cycle.

Once the pressure vessel is full the discharge cycle commences and again the length of this is determined by the product properties and the distance from the vessel to the discharge point, the greater the distance, the longer the cycle.

Pumps in accordance with the second embodiment are particularly adapted for use in the transporting of products where the centrifugal, positive displacement or diaphragm fails for one reason or another. They are utilised in the mining sector to clean drain pits. One good example is in the coal mining where diaphragm pumps don't last due to the seals leaking because particles stayed on the seats.

Drilling rigs in the ocean may use these pumps to move the separated tailings from the screens onto containers so they can be disposed in an environmentally friendly way.

They may be used in the cleaning of sediments of tanks, cleaning of digesters in water treatment plants, cleaning of settling ponds where the sediment becomes heavy and thick slurry.

In the FIGS. 5 to 10, there is provided a housing 10 in the form of a pressure vessel with two inlet openings 11 and 12. The inlet opening 11 is a gravity feed entry (blanked off and inoperable in this illustration), although the feed may be induced into the vessel under a slight vacuum. Inlet 12 is connected via a vacuum hose or pipe to a suction nozzle 13 which has a 25″ Hg vacuum applied together with the full force of the induced airflow. The inlet 12 is controlled with knifegate valve 14 to control the flow.

A vacuum ejector 16 is fitted and is controlled by both a valve 17 on the air supply side and a knifegate valve 20 which seals the vessel when in the pressure or discharge cycle.

An outlet 21 is provided where the product exits the pressure vessel controlled by a knifegate valve 22 Valves 14, 17, 20 and 22 are mechanically operated with one pneumatic cylinder each. When the cycle is suction, the inlet and ejector valves are open and the discharge valve is closed, valve 22 located after at the bottom of the tank is opened allowing the product to exit through an enclosed pipeline up to 1000 metres from the vessel. The system allows for the recovered product to be delivered down the pipeline in both dense and lean phase depending on the distance and the physical properties of the product.

Timers control the length of each cycle. These timers are pneumatically operated and need to be adjusted according to the properties and behaviour of the product to be transported.

The length of the suction cycle is determined by the product properties and distance from the suction nozzle to the pressure vessel. The greater the distance and the less viscous the product the longer the cycle needs to be.

Once the pressure vessel is full the discharge cycle commences and again the length of this is determined by the product properties and the distance from the vessel to the discharge point, the greater the distance, the longer the cycle.

The apparatus in accordance with the foregoing embodiment is particularly adapted for the collection and transfer of drill cuttings generated by offshore drill rigs in the oil and gas exploration industry. The cuttings produced in the drilling process are carried back to the rig suspended in the “drill mud”; this is then recovered to be reused, with several techniques employed, the most common being passing the returning mud over a series of shaker screens. The remaining cuttings have several characteristics which make them difficult or even impossible to handle with standard pumps, these include a coating of the drill mud, their temperature, around 90 degree centigrade out of hole and the coagulative effect rapid cooling has on them. Current handling methods include the recovery by vacuum, auger, pressure pot (dense phase) or even adding mud to make a pumpable slurry. The vacuum systems in use all generate their vacuum via an electrically driven blower, the cutting are recovered to a hopper with some systems utilising a rotary valve which allows the product to be dropped into a pressure pot and then discharged using dense phase to transfer the cutting to their container. The system allows for the vacuum to be generated on the same vessel that is pressurised to deliver the cuttings to their final destination prior to shipping back to shore. The advantage and therefore the difference between the present system and any other available system, be they single, or a combination of methods, is its size, the present system having the smallest footprint of any system available, and is by far the simplest. The systems unique ability to handle an extremely wide range or products ranging from the cuttings either wet or dry, to the drill mud in either oil or brine based make it a very versatile piece of offshore equipment.

In the embodiment of FIGS. 11 to 13, the pressure vessel 50 is oriented vertically, and to maximize the benefit associated with this, an internal cone 54 has been fitted this aligns with the relocated discharge port 53 which is now in the centre of the dished end. There is also the addition of a small air inlet socket 55 which gives the option of educting the material from the tank on the discharge cycle. Secondly the internal neck of the ejector penetration 52 has been lengthened to ensure minimum carry over of product between the material inlet 51 and the air being evacuated via the ejector module fitted to 52.

Apart from these the functionality is identical to the previous embodiment; it utilizes exactly the same double acting knifegate valve and ejector module so the components are interchangeable. The vertical embodiment is capable of handling the same material and therefore can be utilized in the same applications as the previous embodiment, and with the vessel orientation being vertical allows for a much wider range in the moisture content of any material being recovered and transferred.

It will of course be realised that while the above has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention defined in the claims appended hereto.

Claims

1. Pump apparatus including: a housing having an inlet for admitting to the housing a material to be pumped, and a delivery outlet;a knifegate valve on each of said inlet and said outlet said inlet and outlet valves being mechanically interconnected to effect the cyclic operation of the respective valves by a common actuator;control means adapted to selectively operate said actuator to open and close respective said valves;an ejector assembly associated with said inlet and having a compressed air driven venturi and an ejector valve after the venturi being opened by said control means to reduce the pressure in said housing via said venturi and inlet to admit said material to said housing when said inlet valve is opened, and being closed by said control means to pressurize the housing to effect discharge from the housing when said outlet valve is open, said control means being adapted to close said inlet gate means on admission of a selected charge of said material to said housing.

2. Pump apparatus according to claim 1, wherein said control means is pneumatically operated.

3. Pump apparatus according to claim 1, wherein said common actuator and ejector valve are pneumatic in operation.

4. Pump apparatus according to claim 3, wherein said control means controls the amount of material admitted to the housing for each cycle by any one of an empirically determined time basis, metering by weight, or metering by volume, such as by a paddlewheel in the inlet supply.

5. Pump apparatus according to claim 4, wherein said metering by weight is done via a transducer or the like cooperating with the control means.

6. Pump apparatus according to claim 4, wherein said metering by volume is done by a paddlewheel in the inlet supply cooperating with the control means.

7. Pump apparatus according to claim 1, wherein said inlet is associated with storage means for accumulating product prior to pumping.

8. Pump apparatus according to claim 7, wherein said storage means comprises a hopper configured to deliver said product with some gravity assistance.

9. Pump apparatus according to claim 1, wherein the waste air from said venturi during the vacuum phase is vented into the product line downstream of said outlet valve.

10. A method of conveying product using the pump apparatus according to claim 6, wherein said compressed air generates a vacuum via said ejector incorporating said venturi and which evacuates the air from the housing through said inlet, opening said inlet valve to suck the product into the housing until the housing is charged, closing the inlet valve and ejector valve blocking said venturi causing the compressed air supply to pressurize said housing, and opening said outlet valve to permit pressure emptying of the housing.

11. Pump apparatus including: a housing having an inlet for admitting to the housing a material to be pumped, and a delivery outlet;a knifegate valve on each of said inlet and said outlet, the inlet and outlet valves being cyclically operable by an actuator to open and close respective said inlet and outlet valves under control of control means;an ejector assembly associated with said inlet and having a compressed air driven venturi and an ejector valve after the venturi being opened by said control means to reduce the pressure in said housing via said venturi and inlet to admit said material to said housing when said inlet valve is opened, and being closed by said control means to pressurize the housing to effect discharge from the housing when said outlet valve is open, said control means being adapted to close said inlet gate means on admission of a selected charge of said material to said housing, the waste air from said venturi being vented into the product line downstream of the closed said outlet valve.

12. Pump apparatus according to claim 11, wherein said actuator and ejector valve are pneumatic in operation.

13. Pump apparatus according to claim 11, wherein said control means is pneumatically operated.

14. Pump apparatus according to claim 13, wherein said actuator and ejector valve are pneumatic in operation.

15. Pump apparatus according to claim 14, wherein said control means controls the amount of material admitted to the housing for each cycle by any one of an empirically determined time basis, metering by weight, or metering by volume, such as by a paddlewheel in the inlet supply.

16. Pump apparatus according to claim 15, wherein said metering by weight is done via a transducer or the like cooperating with the control means.

17. Pump apparatus according to claim 4, wherein said metering by volume is done by a paddlewheel in the inlet supply cooperating with the control means.

18. Pump apparatus according to claim 11, wherein said inlet is associated with storage means for accumulating product prior to pumping.

19. Pump apparatus according to claim 18, wherein said storage means comprises a hopper configured to deliver said product with some gravity assistance.