Patent Application
20150345516
The present invention relates to pumps for pumping slurry, sludge, solid laden fluids that are generally difficult to displace. More specifically, the present invention is related to a vacuum assisted pump with an integrated instrumentation and control system for pumping such fluids.
Known in the art, there are vacuum assisted pumps used for pumping slurries having a pump body with a lower portion having inlet and outlet check valves. An air nozzle is positioned in an upper portion of the pump body to selectively establish any desired vacuum level and flow rate by means of a control circuit using opto-electronic liquid level sensors. An example of such a pump is disclosed in U.S. Pat. No. 5,007,803 by DiVito et al.
However, such know vacuum assisted pumps for slurries have the disadvantage that their sensors become clogged or dirty during use, which forces operators to clean regularly the inside of the pump, using substantial amounts of water and causing downtime. Furthermore, those known pumps also do not allow adjusting the thickness of the slurry inside the pump body.
There is a need in the market for a vacuum assisted pump that is less prone to clogging, is easier to clean, uses less water and could adjust the thickness of the slurry.
More specifically, in accordance with the present invention, there is provided a pump system for pumping a fluid product including slurry, sludge or solid laden fluids, comprising : a pump body for receiving the fluid product, the pump body having a product inlet and a product outlet with respective one-way check valves; a liquid inlet for communicating a liquid source with the pump body; a vacuum inlet for communicating a vacuum source with the pump body; a product detector for detecting at least one parameter of the fluid product inside the pump body; and a control system for controlling operation of the liquid source, the vacuum source and the product detector; wherein the product detector comprises a radio frequency level detector for detecting a level of the fluid product inside the pump body by emitting radio frequency signals that are received by the control system.
In accordance with another aspect of the present invention, there is provided a pump system for pumping a fluid product including slurry, sludge or solid laden fluids, comprising: a pump body for receiving the fluid product, the pump body having a product inlet and a product outlet with respective one-way check valves; a liquid inlet for communicating a liquid source with the pump body; a vacuum inlet for communicating a vacuum source with the pump body; a product detector for detecting at least one parameter of the fluid product inside the pump body; and a control system for controlling operation of the liquid source, the vacuum source and the product detector; wherein the liquid inlet is in communication with a liquid spray device inside the pump body.
Preferably, the liquid spray device comprises a water spray ball for cleaning the inside of the pump body or adjusting a thickness of the fluid product.
In embodiments, the pump system operates as follow: compressed air is used to generate vacuum, which draws product into the pump body until an internal sensor detects when the pump body is full. When full, the vacuum is stopped and compress air is used to push the product out of the pump system for a user set time by a timer control. When the discharge timer is complete, the compressed air is stopped and vacuum/compressed air cycle repeats.
Preferably, the pump system uses only two mechanical wear/service parts i.e. the inlet and outlet check valves. Preferably, the check valves are metal check valves which feature a knife edge cutting seat that is designed to cut soft solids to ensure sealing during closing operation. The check valves do not require mechanical closing assistance. The check valves include a self-adjusting flap alignment to assist with flap closure.
Advantageously, the pump system of the present invention has a sealless, minimum maintenance design. The pump system does not require rotating shafts or sliding parts to seal. It requires no motors, shafts, seals, bearings, gearboxes or other rotating, sliding or close fitting wear parts.
Advantageously, the pump system of the present invention allows water conservation. Indeed, the pump system transports any flowable or semi-flowable material with little or no water addition.
In embodiments, the pump system features automatic cleaning, wherein sensors detect when cleaning is required and automatically clean the system with water.
In embodiments, the pump system features automatic slurry thickness adjustment. Slurry thickness (viscosity) is automatically monitored and adjusted to maintain pump ability. Water is automatically added only when necessary.
In embodiments, the pump system features automatic energy conservation. Automatic shut off if no product available to pump; automatic restart when product is available.
In embodiments, the pump system features automatic or manual purge function to evacuate and flush discharge piping or for product recovery.
Advantageously, the pump system of the present invention features large size solids passing capability. It is adapted to receive pump pipeline-size solids through the system. For example a 100 mm (4″) unit passes a 100 mm (4″) solid.
In embodiments, the pump system is able to operate “dry” (no fluid or slurry present) continuously without damage.
In embodiments, the pump system requires approximately ¼ the floor space of traditional pump equipment.
In embodiments, the pump system can be used in place of, or to replace traditional equipment including:—Positive displacement pumps such as: progressive cavity pumps, lobe/rotary piston pumps, peristaltic hose pumps, reciprocating piston pumps, gear pumps, Sine pumps, etc.;—Centrifugal pumps where water is added to fluidize product for pumping (the present pump system requires little or no water);—Screw augers and conveyors; and Manual transport systems such as forklift totes and bins.
Other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of specific embodiments thereof, given by way of example only with reference to the accompanying drawings.
In the appended drawings:
The present invention is illustrated in further details by the following non-limiting examples.
The table below refers to the elements illustrated in
Referring to FIGS. 1A and 1B, there is shown a schematic diagram of a vacuum pump system with an integrated control system, according to a preferred embodiment of the present invention.
Referring to
According to a preferred embodiment, the pump system for pumping a fluid product including slurry, sludge or solid laden fluids, includes: a pump body 14 for receiving the fluid product, the pump body having a product inlet 12 and a product outlet 13 with respective one-way check valves; a liquid inlet 8″ for communicating a liquid source with the pump body 14; a vacuum inlet 10′ for communicating a vacuum source with the pump body 14; a product detector 9 for detecting at least one parameter of the fluid product inside the pump body; and a control system 1 for controlling operation of the liquid source, the vacuum source and the product detector 9; wherein the product detector comprises a radio frequency level detector for detecting a level of the fluid product inside the pump body by emitting radio frequency signals that are received by the control system 1.
The radio frequency level detector 9 may include a radio frequency point-level switch made by Babbit International from Houston, Tex. Babbit International point level switches models include LS2000 Low-Cost Sensor, LS600 Basic Feature Sensor, LS7000 dual-point sensor, LS8000 multi-point Sensor with Remote Electronics and MLS-4EX Multi-Point Float Level Switch.
As best illustrated in
As best illustrated in
According to another preferred embodiment, the pump system for pumping a fluid product including slurry, sludge or solid laden fluids, includes: a pump body 14 for receiving the fluid product, the pump body having a product inlet 12 and a product outlet 13 with respective one-way check valves; a liquid inlet 8″ for communicating a liquid source with the pump body 14; a vacuum inlet 10′ for communicating a vacuum source with the pump body 14; a product detector 9 for detecting at least one parameter of the fluid product inside the pump body; and a control system 1 for controlling operation of the liquid source, the vacuum source and the product detector 9; wherein the liquid inlet 8 is in communication with a liquid spray device 11 inside the pump body 14.
Referring to
All operations are controlled via #1 PLC with three operation modes: OFF/ON/PURGE.
OFF: #5 valve unpowered (closed) to isolate #14 pump body from air/vacuum distribution system. All operational functions are disabled
ON: Pump system operates automatically. #5 valve powered (open).
With many difficult to pump products, water is frequently added to the product to increase its ability to be pumped. Most often the product is close to un-flowable. Such products would require specialized pumping or conveyor systems to transport them. Adding water to the product “thins” the product to provide a more flowable consistency.
In all pumping systems, water would be added externally to the pumping system, most often continuously whether it is needed or not.
The vacuum assisted pump technology of the present invention utilizes two methods to reduce water demand for slurry thinning:
Certain type of products with a viscous to “sticky” consistency will eventually coat the interior of the pumping system. To prevent this product build-up is monitored by the #9 radio frequency product detector.
The radio frequency product detector detects if product build-up (sticks) to a metal rod. The radio frequency is adjustable for sensitivity. Higher sensitivity allows less build-up before activating the cleaning cycle.
The cleaning sequence is activated when at the end of the discharge sequence the suction sequence resumes and immediately returns to the discharge sequence. This indicates product coating on the #9 radio frequency product detection rod.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2013/050210 | 3/15/2013 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 61733082 | Dec 2012 | US |
