Chopper pumps
Encyclopedia
A chopper pump is a centrifugal pump
Centrifugal pump
A centrifugal pump is a rotodynamic pump that uses a rotating impeller to create flow by the addition of energy to a fluid. Centrifugal pumps are commonly used to move liquids through piping...

, which is equipped with a cutting system to facilitate chopping/maceration of solids that are present in the pumped liquid. The main advantage of this type of pump is that it prevents clogging of the pump itself and of the adjacent piping, as all the solids and stringy materials are macerated by the chopping system. Chopper pumps exist in various configurations, including submersible and dry-installed design and they are typically equipped with an electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

 to run the impeller
Impeller
An impeller is a rotor inside a tube or conduit used to increase the pressure and flow of a fluid.- Impellers in pumps :...

 and to provide torque for the chopping system. Due to its high solids handling capabilities, the chopper pump is often used for pumping sewage
Sewage
Sewage is water-carried waste, in solution or suspension, that is intended to be removed from a community. Also known as wastewater, it is more than 99% water and is characterized by volume or rate of flow, physical condition, chemical constituents and the bacteriological organisms that it contains...

, sludge, manure slurries, and other liquids that contain large or tough solids.

History

The chopper pump was invented in 1950 by the Danish company Landia. The innovative pump manufacturer, Christian Øllgaard, developed a pump with a special knife system to meet the need for macerating and pumping manure in agricultural applications. Manure with high solids content, containing straw and sawdust, would clog up other types of pumps, causing unstable operation in an environment which required high reliability.

As the need for the pumping of difficult media expanded to other industries, so did the use of the chopper pump in both dry and submersible applications and in various industries, including meat, paper and food processing, as well as the automobile industry, biogas, chemical plants, municipal wastewater and prison lift stations. The chopper pump became, because of its durability and high quality, a large success and formed the basis of Landia's further development of products and know-how. Today, thousands of chopper pumps are operating Worldwide to provide reliable non-clog pump operation.

Working principle

A chopper pump is operated by a drive unit (e.g. electric motor, hydraulic motor, PTO
Power take-off
A power take-off or power takeoff is a splined driveshaft, usually on a tractor or truck, that can be used to provide power to an attachment or separate machine. It is designed to be easily connected and disconnected...

), which turns the impeller and the cutting system. An open impeller design is used to successfully pass the macerated solids or thick slurry. A set of hardened steel cutters is installed externally to the pump suction in order to macerate all solids prior to entering the hydraulic parts of the pump. A chopper pump should not be confused with a grinder pump, which uses its impeller as part of the cutting mechanism. Grinder pumps are typically used for light weight sewage applications, whereas chopper pumps are used for tough solids handling applications. The chopping system consists of a set of rotating cutters that are keyed to the shaft and work in conjunction with the stationary cutters, which are bolted to the suction plate. A system of mechanical seals are used to prevent the pumped liquid from entering the motor. The pump can either be connected to a pipe, flexible hose or lowered down a guide rail so that the pump sits on a coupling foot (aka base elbow), thereby connecting it to the discharge pipe.

Applications

Examples of applications where chopper pumps are commonly applied include:
  • Scum pumping at wastewater treatment plants
  • Sewage wet wells and lift stations
  • Sludge pumping at biogas
    Biogas
    Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal dung, and kitchen waste can be converted into a gaseous fuel called biogas...

    facilities
  • Pumping agricultural manure (dairy, hog and poultry)
  • Septage receiving stations
  • Waste processing at slaughterhouses, poultry abatoirs, fish processing plants, etc.
  • Paper mills / pumping of pulp
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK