PUMPS AND LOCATION OF PUMPING STATIONS
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A pump is a machine that draws a fluid into itself through an entrance port and forces the fluid out through a machine that draws a fluid into itself through an entrance port and forces the fluid out through an exhaust port. A pump may serve to move liquid, as in a cross-country pipeline; to lift liquid, as from a well or to the top of a tall building; or to put fluid under pressure, as in a hydraulic brake. These applications depend predominantly upon the discharge characteristic of the pump. A pump may also serve to empty a container, as in a vacuum pump or a sump pump, in which case the application depends primarily on its intake characteristic.haust port . A pump may also serve to empty a container, as in a vacuum pump or asump pump, in which case the application depends primarily on its intake characteristic.
Pumps are machines that uses energy to raise, transport, or compress fluids. Pumps are classified by how they transfer energy to the fluid. The basic methods are volume displacement, addition of kinetic energy, and use of electromagnetic force. Pumps in which displacement is accomplished mechanically are called positive displacement pumps. Kinetic pumps pass kinetic energy to the fluid by means of a rapidly rotating impeller . To use electromagnetic force, the fluid being pumped must be a good electrical conductor. Pumps used to transport or pressurize gases are called compressors, blowers, or fans.to raise, transport, or compress fluids.
Pumps are mainly divided into two
1. DISPLACEMENT PUMPS OR RECIPROCATING PUMPS
Displacement pumps are batch delivery, periodic energy addition devices whose fluid displacement volume (or volumes) is set in motion and positively delivers that batch of fluid from a lower to higher pressure irrespective of the value of that higher pressure.In positive displacement pump delivery is fixed.
Fig 1.Displacement pump
1.1 POSITIVE DISPLACEMENT PUMPS
Fig 2.Positive displacement rotary pump
Positive displacement rotary pumps are pumps that move fluid using the principles of rotation. The vacuum created by the rotation of the pump captures and draws in the liquid. Rotary pumps are very efficient because they naturally remove air from the lines, eliminating the need to bleed the air from the lines manually. Positive displacement rotary pumps also have their weaknesses. Because of the nature of the pump, the clearance between the rotating pump and the outer edge must be very close, requiring that the pumps rotate at a slow, steady speed. If rotary pumps are operated at high speeds, the fluids will cause erosion, much as ocean waves polish stones or erode rock into sand. Rotary pumps that experience such erosion eventually show signs of enlarged clearances, which allow liquid to slip through and detract from the efficiency of the pump. Positive displacement rotary pumps can be grouped into three main types.
Fig 3.Gear pump Fig 3a.External gear pump Fig 3b.Internal gear pump
Gear pumps are the simplest type of rotary pumps, consisting of two gears laid out side-by-side with their teeth enmeshed. The gears turn away from each other, creating a current that traps fluid between the teeth on the gears and the outer casing, eventually releasing the fluid on the discharge side of the pump as the teeth mesh and go around again. Many small teeth maintain a constant flow of fluid, while fewer, larger teeth create a tendency for the pump to discharge fluids in short, pulsing gushes.The two types of gear pumps are external gear pumps and internal gear pumps.
Screw pumps are a more complicated type of rotary pumps, featuring two screws with opposing thread that is, one screw turns clockwise, and the other counterclockwise. The screws are each mounted on shafts that run parallel to each other; the shafts also have gears on them that mesh with each other in order to turn the shafts together and keep everything in place.
Fig 4.Screw pumps
The turning of the screws, and consequently the shafts to which they are mounted, draws the fluid through the pump. As with other forms of rotary pumps, the clearance between moving parts and the pump's casing is minimal.
c.MOVING VANE PUMPS
Fig 5.Moving vane pumps
Moving vane pumps are the third type of rotary pumps, consisting of a cylindrical rotor encased in a similarly shaped housing. As the rotor turns, the vanes trap fluid between the rotor and the casing, drawing the fluid through the pump.
Positive Displacement Pumps has an expanding cavity on the suction side and a decreasing cavity on the discharge side. Liquid flows into the pumps as the cavity on the suction side expands and the liquid flows out of the discharge as the cavity collapses. The volume is constant given each cycle of operation.
The positive displacement pumps can be divided into two main classes
The positive displacement principle applies whether the pump is a
• rotary lobe pump
• progressing cavity pump
• rotary gear pump
• piston pump
• diaphragm pump
• screw pump
• gear pump
• hydraulic pump
• vane pump
• regenerative (peripheral) pump
Positive Displacement Pumps, unlike Centrifugal or Roto-dynamic Pumps, will produce the same flow at a given speed (RPM) no matter the discharge pressure.Positive Displacement Pumps are "constant flow machines".
A Positive Displacement Pump must not be operated against a closed valve on the discharge side of the pump because it has no shut-off head like Centrifugal Pumps. A Positive Displacement Pump operating against a closed discharge valve, will continue to produce flow until the pressure in the discharge line are increased until the line bursts or the pump is severely damaged or both.
A relief or safety valve on the discharge side of the Positive Displacement Pump is therefore absolutely necessary. The relief valve can be internal or external. The pump manufacturer normally has the option to supply internal relief or safety valves. The internal valve should in general only be used as a safety precaution, an external relief valve installed in the discharge line with a return line back to the suction line or supply tank is recommended.
1.2 RECIPROCATING PUMPS
Typical reciprocating pumps are
Fig 6. Plunger pump
A plunger pump consists of a cylinder with a reciprocating plunger in it. The suction and discharge valves are mounted in the head of the cylinder. In the suction stroke the plunger retracts and the suction valves open causing suction of fluid into the cylinder. In the forward stroke the plunger pushes the liquid out of the discharge valve.With only one cylinder the fluid flow varies between maximum flow when the plunger moves through the middle positions, and zero flow when the plunger is at the end positions. A lot of energy is wasted when the fluid is accelerated in the piping system. Vibration and "water hammer" may be a serious problem. In general the problems are compensated for by using two or more cylinders not working in phase with each other.
In diaphragm pumps, the plunger pressurizes hydraulic oil which is used to flex a diaphragm in the pumping cylinder. Diaphragm valves are used to pump hazardous and toxic fluids
Fig 7. Diaphragm pump
This uses two meshed gears rotating in a closely fitted casing. Fluid is pumped around the outer periphery by being trapped in the tooth spaces. It does not travel back on the meshed part, since the teeth mesh closely in the centre. It is widely used on car engine oil pumps. It is also used in various hydraulic power packs
d.PROGRESSING CAVITY PUMPS
Widely used for pumping difficult materials such as sewage sludge contaminated with large particles, this pump consists of a helical shaped rotor, about 10 times as long as its width. This can be visualized as a central core of diameter x, with typically a curved spiral wound around of thickness half x, although of course in reality it is made from one casting. This shaft fits inside a heavy duty rubber sleeve, of wall thickness typically x also. As the shaft rotates, fluid is gradually forced up the rubber sleeve. Such pumps can develop very high pressure at quite low volumes.
Fig 8.Progressing cavity pump
Fig 9.Roots- type pump
The low pulsation rate and gentle performance of this Roots-type positive displacement pump is achieved due to a combination of its two 90° helical twisted rotors, and a triangular shaped sealing line configuration, both at the point of suction and at the point of discharge. This design produces a continuous and non-vorticuless flow with equal volume. High capacity industrial "air compressors" have been designed to employ this principle, as well as most "superchargers" used on internal combustion engines, and even a brand of civil defense siren.
Fig 10.Peristaltic pump
A peristaltic pump is a type of positive displacement pump used for pumping a variety of fluids. The fluid is contained within a flexible tube fitted inside a circular pump casing . A rotor with a number of "rollers", "shoes" or "wipers" attached to the external circumference compresses the flexible tube. As the rotor turns, the part of the tube under compression closes thus forcing the fluid to be pumped to move through the tube. Additionally, as the tube opens to its natural state after the passing of the cam fluid flow is induced to the pump. This process is called peristalsis and is used in many biological systems such as the gastrointestinal tract.
1.3 RECIPROCATING TYPE PUMPS
Reciprocating-type pumps require a system of suction and discharge valves to ensure that the fluid moves in a positive direction. Pumps in this category range from having "simplex" one cylinder, to in some cases "quad" four cylinders or more. Most reciprocating-type pumps are "duplex" (two) or "triplex" (three) cylinder. Furthermore, they can be either "single acting" independent suction and discharge strokes or "double acting" suction and discharge in both directions. The pumps can be powered by air, steam or through a belt drive from an engine or motor. This type of pump was used extensively in the early days of steam propulsion (19th century) as boiler feed water pumps. Though still used today, reciprocating pumps are typically used for pumping highly viscous fluids including concrete and heavy oils and special applications demanding low flow rates against high resistance..
a.COMPRESSED-AIR-POWERED DOUBLE-DIAPHRAGM PUMPS
Fig 11.Double-diaphragm pump
One modern application of positive displacement diaphragm pumps is compressed-air-powered double-diaphragm pumps. Run on compressed air these pumps are intrinsically safe by design.They are relatively inexpensive and can be used for almost any duty from pumping water out of bunds, to pumping hydrochloric acid from secure storage (dependent on how the pump is manufactured - elastomers / body construction).
b.HYDRAULIC RAM PUMPS
Fig 12.Hydraulic ram pump
A hydraulic ram is a water pump powered by hydropower.It functions as a hydraulic transformer that takes in water at one "hydraulic head" (pressure) and flow-rate, and outputs water at a higher hydraulic-head and lower flow-rate. The device utilizes the water hammer effect to develop pressure that allows a portion of the input water that powers the pump to be lifted to a point higher than where the water originally started.The hydraulic ram is sometimes used in remote areas, where there is both a source of low-head hydropower, and a need for pumping water to a destination higher in elevation than the source. In this situation, the ram is often useful, since it requires no outside source of power other than the kinetic energy of flowing water.
The other types of pumps are Buoyancy pumps and Impulse pumps.
2. ROTO-DYNAMIC PUMPS OR CENTRIFUGAL PUMPS
Kinetic pumps are continuous delivery, continuous energy addition devices that build up kinetic energy in the rotating element or impeller and convert most of that energy into static energy to a point where the fluid delivery to the higher pressure level commences. The delivery is affected by the value of the discharge pressure that must be overcome.The kinetic pump will deliver an increasing amount of liquid as the discharge pressure is lowered.
Fig 13.Centrifugal pump
2.1 ROTODYNAMIC PUMPS
Rotodynamic pumps (or dynamic pumps) are a type of velocity pump in which kinetic energy is added to the fluid by increasing the flow velocity. This increase in energy is converted to a gain in potential energy (pressure) when the velocity is reduced prior to or as the flow exits the pump into the discharge pipe. This conversion of kinetic energy to pressure can be explained by the First law of thermodynamics or more specifically by Bernoulli's principle. Dynamic pumps can be further subdivided according to the means in which the velocity gain is achieved.
These types of pumps have a number of characteristics:
1. Continuous energy
2. Conversion of added energy to increase in kinetic energy(increase in velocity)
3. Conversion of increased velocity (kinetic energy) to an increase in pressure head
One practical difference between dynamic and positive displacement pumps is their ability to operate under closed valve conditions. Positive displacement pumps physically displace the fluid; hence closing a valve downstream of a positive displacement pump will result in a continual build up in pressure resulting in mechanical failure of either pipeline or pump. Dynamic pumps differ in that they can be safely operated under closed valve conditions (for short periods of time).
2.2 CENTRIFUGAL PUMPS
A centrifugal pump is a rotodynamic pump that uses a rotating impeller to increase the pressure and flow rate of a fluid. Centrifugal pumps are the most common type of pump used to move liquids through a piping system. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward or axially into a diffuser or volute chamber, from where it exits into the downstream piping system. Centrifugal pumps are typically used for large discharge through smaller heads.
a.SCREW CENTRIFUGAL PUMPS
The screw centrifugal pump is a popular choice for handling delicate products such as food and crystals. Its low shear characteristic reduces emulsification when pumping mixtures making it ideal for pumping oily water and Return Activated Sludge [RAS] as it does not damage the floc.
Fig 14.Screw centrifugal pump
The pump's ability to pass long fibrous materials such as rope without clogging makes it a frequent choice for municipal waste water applications. A screw centrifugal pump typically has an operating efficiency of 70% to 85%. It has a relatively steeply rising head/capacity curve shape giving it good flow control capability over its allowable operating range
The impeller has a single blade, axially extended at the inlet and developed around its axis much like a corkscrew. Linking this to a centrifugal outlet allows pumping with the minimum of agitation and shear, essential factors when product bruising, liquid emulsification or clogging is to be avoided.
The screw centrifugal impeller features:
• Large free passages for pumping liquid with solid objects and fibrous materials
• Able to pump liquids and viscosities above values normally possible with conventional centrifugal pumps
• Steep H/Q curves with closed valve twice best efficiency point
• Low NPSH characteristics
• Flat non-overloading power curves
• High hydraulic efficiencies
Typical application areas:
• Sump emptying
• Industrial effluent treatment
• Feeding oily water separators
• Transfer of 'live' fish
• Oil and Chemical spillages
• Mine Drainage
• Parts washer equipment
• Processing of waste oils & sludges
• Transfer of fruit and vegetables
• Municipal waste water treatment plants
b.RADIAL FLOW PUMPS
Fig 15.Radial flow pump
Often simply referred to as centrifugal pumps. The fluid enters along the axial plane, is accelerated by the impeller and exits at right angles to the shaft (radially). Radial flow pumps operate at higher pressures and lower flow rates than axial and mixed flow pumps.
c.AXIAL FLOW PUMPS
Fig 16.Axial flow pump
Axial flow pumps differ from radial flow in that the fluid enters and exits along the same direction parallel to the rotating shaft. The fluid is not accelerated but instead "lifted" by the action of the impeller. They may be likened to a propeller spinning in a length of tube. Axial flow pumps operate at much lower pressures and higher flow rates than radial flow pumps.
d.MIXED FLOW PUMPS
Mixed flow pumps, as the name suggests, function as a compromise between radial and axial flow pumps, the fluid experiences both radial acceleration and lift and exits the impeller somewhere between 0-90 degrees from the axial direction. As a consequence mixed flow pumps operate at higher pressures than axial flow pumps while delivering higher discharges than radial flow pumps. The exit angle of the flow dictates the pressure head-discharge characteristic in relation to radial and mixed flow.
Fig 17.Mixed flow pump
Fig 18.Educator-jet pump
This uses a jet, often of steam, to create a low pressure. This low pressure sucks in fluid and propels it into a higher pressure region.
Gravity pumps include the syphon and Heron's fountain- and there also important qanat or foggara systems which simply use downhill flow to take water from far-underground aquifers in high areas to consumers at lower elevations. The hydraulic ram is also sometimes referred to as a gravity pump.
Fig 19.Gravity pump
g. STEAM PUMPS
Steam pumps are now mainly of historical interest. They include any type of pump powered by a steam engine and also pistonless pumps such as Thomas Savery’s pump and the Pulsometer steam pump.
Fig 20.Steam pump
3.ADVANTAGES AND DISADVANTAGES OF RECIPROCATING PUMPS
• Reciprocating pumps will deliver fluid at high pressure (High Delivery Head).
• They are 'Self-priming' - No need to fill the cylinders before starting.
• Reciprocating pumps give a pulsating flow.
• The suction stroke is difficult when pumping viscous liquids.
• The cost of producing piston pumps is high. This is due to the very accurate sizes of the cylinders and pistons. Also, the gearing needed to convert the rotation of the drive motor into a reciprocating action involves extra equipment and cost.
• The close fitting moving parts cause maintenance problems, especially when the pump is handling fluids containing suspended solids, as the particles can get into the small clearances and cause severe wear
• They give low volume rates of flow compared to other types of pump
EXTERNAL GEAR PUMPS
• High speed
• High pressure
• No overhung bearing loads
• Relatively quiet operation
• Design accommodates wide variety of materials
• Four bushings in liquid area
• No solids allowed
• Fixed End Clearances
INTERNAL GEAR PUMPS
• Only two moving parts
• Only one stuffing box
• Non-pulsating discharge
• Excellent for high-viscosity liquids
• Constant and even discharge regardless of pressure conditions
• Usually requires moderate speeds
• Medium pressure limitations
• One bearing runs in the product pumped
• Overhung load on shaft bearing
• Pass medium solids
• No metal-to-metal contact
• Superior CIP/SIP capabilities
• Long term dry run (with lubrication to seals)
• Non-pulsating discharge
• Requires timing gears
• Requires two seals
• Reduced lift with thin liquids
PROGRESSING CAVITY PUMPS
• High suction lift capabilities
• Gentle pumping action so that very little shear is imparted to the liquid being pumped
• Ability to handle low or high viscosity products with or without solids
• Pressure stability over a wide speed range
• Flows are directly proportional to the speed,for easy pumping control
• Handles thin liquids at relatively higher pressures
• Compensates for wear through vane extension
• Sometimes preferred for solvents, LPG
• Can run dry for short periods
• Can have one seal or stuffing box
• Develops good vacuum
• Can have two stuffing boxes
• Complex housing and many parts
• Not suitable for high pressures
• Not suitable for high viscosity
• Not good with abrasives
AIR OPERATED PUMP
• easily transfers high viscosity fluids.
• Can easily suck in from a depth of four metres.
• Does not need pre-filling with fluid.
• Is air operated and therefore explosion-proof.
• not spoil the properties of chemicals
• system is double acting
• pump capacity is limited
4.ADVANTAGES AND DISADVANTAGES OF CENTRIFUGAL PUMPS
The advantages of centrifugal pumps include
• no priming
• weight saving
• adaptability to high-speed prime movers
• Generate a steady flow of liquid
• high flow rates are possible
• low cost of replacement parts
• slurries can be pumped by it
• can be operated against a closed discharge valve
A centrifugal pump is basically a gear inside a bonnet (form-fitting housing). The pumped fluid enters the bonnet near the axis of rotation of the gear. The exit from the bonnet is near the rim of the spinning gear. The centrifugal force, created by the spinning gear, forces the fluid through the bonnet. In the large pumps (meant to pump gases, not liquids), the gear teeth are replaced by paddles and the rotating part is more like a propeller than it is like a gear. Simplicity can be an advantage to a physical system especially one that might run for hours. The fewer parts there are, the fewer parts there are to break down or wear out. Also, the simpler a system is, the easier it is to repair or modify. Simple is good.
Centrifugal pumps can pump a wide variety of substances at variable rates of speed and volume. They are widely used as both water and air pumps in cars, They are used as the pumps in many pneumatic and hydraulic systems like the systems that airplanes use to move ailerons (control surfaces on the wings) and the tail rudder. Centrifugal pumps can pump gases and light liquids. When the liquid gets as thick as oil, it is time to choose another kind of pump.
Centrifugal pumps can be almost any size so small that you need a microscope to work on them and on hangar-size air blowers that fill dirigibles. This is one of the advantages of simplicity, it scales nicely. Centrifugal pumps are often found in vending machines especially those that deliver something liquid, such as coffee or tea. Centrifugal pumps are cheap, low maintaince and seldom jam or clog.
Many kinds of pumps need to be primed to work. For example, there are water pumps that work by displacing one "bite" of water through the pump, which creates a vacuum that the next "bite" flows into. If this pump can't bite, nothing moves. You have to put some water in this pump to start it working even if there is water all the way up to the pump. This can be a serious problem especially when the pump is in a remote or otherwise inaccessible place. Centrifugal pumps don't have this problem. Even a centrifugal pump designed to pump a liquid will simply be pumping air (perhaps inefficiently) until the liquid becomes available. Then it will start pumping the liquid. This means that centrifugal pumps can be put in places where it would be inadvisable to put other kinds of pumps.
The disadvantages of centrifugal pumps are
• relatively poor suction power
• not self-priming
• cannot be used for viscous liquids
• cavitation can cause wear and loss of efficiency
One disadvantage of centrifugal pumps is their relatively poor suction power. When the pump end is dry, the rotation of the impeller, even at high speeds, is simply not sufficient to lift liquid into the pump; therefore, the pump must be primed before pumping can begin. For this reason, the suction lines and inlets of most centrifugal pumps are placed below the source level of the liquid pumped. The pump can then be primed by merely opening the suction stop valve and allowing the force of gravity to fill the pump with liquid. The static pressure of the liquid above the pump also adds to the suction pressure developed by the pump while it is in operation.
Another disadvantage of centrifugal pumps is that they develop cavitation. Cavitation occurs when the velocity of a liquid increases to the point where the consequent pressure drop reaches the pressure of vaporization of the liquid. When this happens, vapor pockets, or bubbles, form in the liquid and then later collapse when subjected to higher pressure at some other point in the flow. The collapse of the vapor bubbles can take place with considerable force. This effect, coupled with the rather corrosive action of the vapor bubbles moving at high speed, can severely pit and corrode impeller surfaces and sometimes even the pump casing. In extreme instances, cavitation has caused structural failure of the impeller blades. Whenever cavitation occurs, it is frequently signaled by a clearly audible noise and vibration (caused by the violent collapse of vapor bubbles in the pump). Several conditions can cause cavitation, not the least of which is improper design of the pump or pumping system. For example, if the suction pressure is abnormally low (caused perhaps by high suction lift or friction losses in the suction piping), the subsequent pressure drop across the impellers may be sufficient to reach the pressure of vaporization. A remedy might be to alter the pump design by installing larger piping to reduce friction loss or by installing a foot valve to reduce suction lift. Cavitation can also be caused by improper operation of the pump. For instance, cavitation can occur when sudden and large demands for liquid are made upon the pump. As the liquid discharged from the pump is rapidly distributed and used downstream, a suction effect is created on the discharge side of the pump. Think of it as a pulling action on the discharge side that serves to increase the velocity of the liquid flowing through the pump. Thus, as the pressure head on the discharge decreases, the velocity of the liquid flowing across the impellers increases to the point where cavitation takes place. Perhaps the easiest way to avoid this condition is to regulate the liquid demand. If this is not possible, then increase the suction pressure by some means to maintain pressure in the pump under these conditions.
5.LOCATION OF PUMPING STATIONS
Pumping stations are facilities including pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure systems, such as the supply of water to canals, the drainage of low-lying land, and the removal of sewage to processing sites.A pumping station is, by definition, an integral part of a Pumped-storage hydroelectricity installation.
CANAL WATER SUPPLY
In countries with canal systems, pumping stations are also frequent. Because of the way the system of canal locks work, water is lost from the upper part of a canal each time a vessel passes through. Also, most lock gates are not watertight, so some water leaks from the higher levels of the canal to those lower down. Obviously, the water has to be replaced or eventually the upper levels of the canal would not hold enough water to be navigable.Canals are usually fed by diverting water from streams and rivers into the upper parts of the canal, but if no suitable source is available, a pumping station can be used to maintain the water level.
New Orleans, United States: Metairie Pumping Station, also known as Pumping Station 6, building, constructed in 1899, near Metairie Road and the head of the 17th StreetCanal. Now housing 15 Wood Screw Pumps, it can move over 6 billion gallons of water a day.When low lying areas of land are drained, the general method is to dig drainage ditches. However, if the area is below sea level then it is necessary to pump the water upwards into water channels that finally drain into the sea.The Victorians understood this concept, and in the United Kingdom they built pumping stations with water pumps, powered by steam engines to accomplish this task. In Lincolnshire, large areas of wetland at sea level, called The Fens, were turned into rich arable farmland by this method. The land is full of nutrients because of the accumulation of sedimentary mud that created the land initially.Elsewhere, pumping stations are used to remove water that has found its way into low-lying areas as a result of leakage or flooding.
PACKAGE PUMPING STATION
In more recent times, a 'package pumping station' provides an efficient and economic way of installing a drainage system. They are suitable for mechanical building services collection and pumping of liquids like surface water, wastewater or sewage from areas where drainage by gravity is not possible.
A package pumping station is an integrated system, built in a housing manufactured from strong, impact-resistant polyethylene or glass-reinforced plastic. The unit is supplied with internal pipework fitted, pre-assembled ready for installation into the ground, after which the submersible pumps and control equipment are fitted. Features may include controls for fully automatic operation; a high-level alarm indication, in the event of pump failure; and possibly a guide-rail/auto-coupling/pedestal system, to permit easy removal of pumps for maintenance.
Pumping stations in sewage collection systems, also called lift stations, are normally designed to handle raw sewage that is fed from underground gravity pipelines (pipes that are laid at an angle so that a liquid can flow in one direction under gravity). Sewage is fed into and stored in an underground pit, commonly known as a wet well. The well is equipped with electrical instrumentation to detect the level of sewage present. When the sewage level rises to a predetermined point, a pump will be started to lift the sewage upward through a pressurized pipe system called a sewer force main or rising main from where the sewage is discharged into a gravity manhole. From here the cycle starts all over again until the sewage reaches its point of destination – usually a treatment plant. By this method, pumping stations are used to move waste to higher elevations.
The pump manufacturers have always designed and manufactured electronic devices to control and supervise the pumping stations. Today it is also very common to use a plc to do such work, but the experience needed to solve certain particular problems, makes an easy choice to look for a specific pump controller.
PUMPED STORGE SCHEMES
A pumped-storage scheme is a type of power station for storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations.Typically, water is channelled from a high-level reservoir to a low-level reservoir, through turbine generators that generate electricity. This is done when the station is required to generate power. During low-demand periods, such as overnight, the generators are reversed to become pumps that move the water back up to the top reservoir.
6.LIST OF PUMPING STATIONS
There are countless thousands of pumping stations throughout the world.
1. United Kingdom
In the UK, during the Victorian Era, there was a fashion for public buildings to feature highly ornate architecture. Consequently, a considerable number of former pumping stations have been listed and preserved. The majority were originally steam-powered, and where the steam engines are still in situ, many of the sites have since re-opened as museum attractions.
a.Canal water supply
• Claverton Pumping Station, on the Kennet and Avon Canal
• Cobb's Engine House, ruin near southern portal of Netherton Tunnel
• Crofton Pumping Station, on the Kennet and Avon Canal, near Great Bedwyn
• Leawood Pump House, on the Cromford Canal in Derbyshire
• Smethwick Engine, now removed from original site to Birmingham Thinktank
Used to pump water from a well into a reservoir
• Bestwood Pumping Station, Nottinghamshire
• Boughton Pumping Station, Nottinghamshire
• Bratch Pumping Station, Staffordshire
• Mill Meece Pumping Station, in Staffordshire
• Papplewick Pumping Station, Nottinghamshire
• Selly Oak Pumping Station, Birmingham
c.Hydraulic power station
• Wapping Hydraulic Power Station, London
• Pinchbeck Engine, near Spalding (preserved beam engine and scoop wheel)
• Pode Hole pumping station, near Spalding, Lincolnshire (formerly steam beam engines, no longer present)
• Prickwillow Engine House, near Ely, Cambridgeshire (now the Museum of Fenland Drainage)
• Stretham Old Engine, Stretham, Cambridgeshire
• Westonzoyland Pumping Station, Somerset
e.Public water supply
Used to pump drinking water from a reservoir into a water supply system.
• Blagdon Pumping Station, Chew Valley, Somerset
• Edgbaston Waterworks, Birmingham (probably not a 'museum' site)
• Kempton Park Pumping Station, London
• Kew Bridge Pumping Station, Kew Bridge, London
• Langford Pumping Station ("Museum of Power"), Essex
• Ryhope Engines Museum, Sunderland
• Abbey Pumping Station, Leicester
• Abbey Mills Pumping Station, in North London. (steam engines no longer present)
• Claymills Pumping Station, near Burton upon Trent
• Coleham Pumping Station, Coleham, near Shrewsbury
• Crossness Pumping Station, in South London
• Dock Road Edwardian Pumping Station, in Northwich, Cheshire (Gas engines. Built 1913)
• Low Hall Pumping Station, Walthamstow, North London
• Markfield Beam Engine, Tottenham, London
• Brunel Engine House (now Brunel Museum), Rotherhithe, East London (extracted water from Thames Tunnel; engine no longer present)
• Shore Road Pumping Station, Birkenhead, Wirral (originally steam, now electric; extracts water from the rail tunnel under the River Mersey)
Public water supply
• Engineer's Office of the Former Pumping Station, Hong Kong
• Nasiriyah Drainage Pump Station, Dhi Qar Province
• Cruquius pumping station (Operational, but no longer steam-powered.)
From the study it is concluded that pumps are a reliable means to move liquids for various applications.These applications depend predominantly upon the discharge characteristics of the pump. Centrifugal pumps are most often associated with the radial flow type. However, the term "centrifugal pump" can be used to describe all impeller type rotodynamic pumps including the radial, axial and mixed flow variations.Reciprocating pumps are also greatly preferred due to their high delivery head and self-priming nature.The choice of location of pumping stations should be done considering the above mentioned factors for successful installations.
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Joined: Feb 2011
10-02-2011, 09:11 AM
please send seminar and presentation masters level on pumps watersupply and valves