Decanter centrifuges: A guide
A decanter centrifuge is an excellent tool for separating liquid and solid mixtures. Industrial work and water processing plants are often tasked with purifying substances with variable amounts of solid material, and a decanter centrifuge is engineered to remove any and all contaminates from sewage and effluent sludge. Centrifuges are also capable of separating disparate fluids such as weighted or non-weighted oil and water based liquids. For example, those in the beverage industry commonly employ decanter centrifuges to extract juices. Utilizing basic gravitational force, the centrifuge divides the denser, weightier solids from the lighter, effluviant liquid. Consequently, decanter centrifuges are utilized by a variety of industries with applications extending from water processing to the manufacturing of stainless steel.
Each decanter is equipped with a hydraulic scroll drive system that allows the user to automatically control the rate of solid material discharge. The design of the device separates solids while still maintaining their weight and consistency. For example, research has shown decanter centrifuges when used to separate mud are able to sustain the material’s viscosity and original composition. The machine provides flexibility as well, with programmable frequencies and an adjustable belt that allows for altered rotation speeds. In addition, the system offers long term reliability, with well maintained equipment lasting for up to 25 years.
The two primary types of decanter centrifuges are:
1. Solid Bowl Decanter Centrifuge
This centrifuge is encased in a shell comprised of two layers. The outer layer has a tapered aperture which allows solids to discharge as the bowl rotates. The inner layer is a hollow case molded to match the outline of the bowl. The resulting centrifuge mitigates the amount of moisture in the cake and produces material with a higher quality centrate. Solid bowl decanters are manufactured with two or three phases, and are generally inexpensive to purchase and maintain. Their environmental impact is minimal and in full compliance with CE regulations.
2. Screen Bowl Decanter Centrifuge
Ranging in 160mm to 1400mm in diameter, screen bowl decanter centrifuges are engineered to separate materials with better overall washing efficiency. Primarily used in separating polyolefins and minerals, these decanters work in multiple phases, starting with sedimentation and clarification before moving on to the water removal process.
Applications of Decanter Centrifuges
The primary application for decanter centrifuges is extracting solid materials from collected sludge. However, despite its singular purpose, the equipment can be utilized by a variety of industries. For example, oil companies employ decanters to separate debris and dirt from crude oil. Refineries also make use of the technology in conjunction with shale shakers and mud cleaners. Companies that sell processed foods and fish depend heavily on decanter centrifuges to ensure the quality of their products. Most importantly, decanter centrifuges are critical to water processing facilities and ensuring our environment is free of unnecessary toxins.