Belt filter
Encyclopedia
The belt filter is an industrial machine
, used for solid/liquid separation processes, particularly the dewatering
of sludge
s in the chemical industry
, mining
and water treatment
. The process of filtration
is primarily obtained by passing a pair of filtering cloths and belts through a system of rollers.
is scraped off into a suitable container.
A belt filter is generally used in phosphatic fertiliser plants to separate the solid from slurry. It comprises washing to different zone to minimise the product losses. Belt filters use a vacuum system to minimise offgas and effluent during operations. It has applications in many other areas of industry.
difference across the filter cloth. The filter cloth is directed though a zone where either pressure or vacuum pushes water from the filter cloths and ultimately to drain.
The sludge can be combined with a filter aid or flocculant
the help the filtration process and reduce blinding of the filter cloth.
Filter cloths can be cleaned throughout the operation of the process by means of water sprays positioned on the return section of the belt.
work scheme of belt press from www.beltpres.net page
Belt Pres
High Efficiency in Sludge Dewatering
Machine
A machine manages power to accomplish a task, examples include, a mechanical system, a computing system, an electronic system, and a molecular machine. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work...
, used for solid/liquid separation processes, particularly the dewatering
Dewatering
Dewatering is the removal of water from solid material or soil by wet classification, centrifugation, filtration, or similar solid-liquid separation processes, such as removal of residual liquid from a filter cake by a filter press as part of various industrial processes.Construction dewatering,...
of sludge
Sludge
Sludge refers to the residual, semi-solid material left from industrial wastewater, or sewage treatment processes. It can also refer to the settled suspension obtained from conventional drinking water treatment, and numerous other industrial processes...
s in the chemical industry
Chemical industry
The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials into more than 70,000 different products.-Products:...
, mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
and water treatment
Water treatment
Water treatment describes those processes used to make water more acceptable for a desired end-use. These can include use as drinking water, industrial processes, medical and many other uses. The goal of all water treatment process is to remove existing contaminants in the water, or reduce the...
. The process of filtration
Filtration
Filtration is commonly the mechanical or physical operation which is used for the separation of solids from fluids by interposing a medium through which only the fluid can pass...
is primarily obtained by passing a pair of filtering cloths and belts through a system of rollers.
Operation
The feed sludge to be dewatered is introduced from a hopper between two filter cloths (supported by perforated belts) which pass through a convoluted arrangement of rollers. As the belts are fed through the rollers, water is squeezed out of the sludge. When the belts pass through the final pair of rollers in the process, the filter cloths are separated and the filter cakeFilter cake
A filter cake is formed by the substances that are retained on a filter. The filter cake grows in the course of filtration, becomes "thicker" as particulate matter is being retained. With increasing layer thickness the flow resistance of the filter cake increases. After a certain time of use the...
is scraped off into a suitable container.
A belt filter is generally used in phosphatic fertiliser plants to separate the solid from slurry. It comprises washing to different zone to minimise the product losses. Belt filters use a vacuum system to minimise offgas and effluent during operations. It has applications in many other areas of industry.
Improvements
The effectiveness of the operation can be increased by creating a pressurePressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...
difference across the filter cloth. The filter cloth is directed though a zone where either pressure or vacuum pushes water from the filter cloths and ultimately to drain.
The sludge can be combined with a filter aid or flocculant
Flocculation
Flocculation, in the field of chemistry, is a process wherein colloids come out of suspension in the form of floc or flakes by the addition of a clarifying agent. The action differs from precipitation in that, prior to flocculation, colloids are merely suspended in a liquid and not actually...
the help the filtration process and reduce blinding of the filter cloth.
Filter cloths can be cleaned throughout the operation of the process by means of water sprays positioned on the return section of the belt.
Pictures
Some of the belt filter presses examples from www.dinworks.fi pagework scheme of belt press from www.beltpres.net page
Belt Pres
High Efficiency in Sludge Dewatering
Further reading
- Coal preparation plantCoal preparation plantA coal preparation plant is a facility that washes coal of soil and rock, preparing it for transport to market. A CPP may also be called a "coal handling and preparation plant" , "prep plant," "tipple," or "wash plant"....
- Verso Paper Sartell Mill