Whether you’re running an operation with a lagoon, a screen bowl centrifuge, a filter press, or anything else, there are some important things to know about mechanical dewatering. Unfortunately, if you know these things, you’ll make a good mess.
Depending on the application, filter presses for mechanical dewatering can perform various tasks. In addition, these dewatering machines offer superior separation performance and low energy consumption. As a result, they are widely used in multiple industries, including the chemical industry, pharmaceutical industry, and municipal wastewater facilities.
Filter presses are used to separate liquids and solids. They can also be adapted to create a hybrid filter press/dryer process. During the hybrid filter press/dryer process, a hot water system is used to heat filter plates. This allows the sludge to be dewatered and dried in a single stage.
The mechanical dewatering technology of filter presses does not require a minimum amount of sludge. In addition, they have shorter cycle times and higher productivity.
Filter presses are equipped with a series of sensors, including speed sensors, belt position sensors, belt tension sensors, and air pressure loss sensors. They also have a safety indication system.
Filter presses have been contributing to the separation of solid-liquid substances for decades. They are widely used in many industries, including the chemical, pharmaceutical, municipal wastewater facilities, and food and beverage industries.
A vertical filter press has a simple structure and can be used in many applications. They are highly corrosion-resistant because of the special geometry of the placement of rolls. They also operate automatically.
Screen Bowl Centrifuges
Generally, a screen bowl centrifuge is a continuous two-stage solid-liquid separator. It consists of a rotary bowl with an aperture bowl section and a screen section. A lattice of ribs forms the screen section. The screen section typically extends the length of the bowl.
The inner surface of the screen section is curved at the radius of the cross-rib lattice. This feature helps prevent the screen from breaking. The screen’s inner surface is also softer and less resistant to wear.
Special tungsten carbide bars are used to assemble the screen. These bars are placed by hand within the circular screen section. The bars are then secured to the frame. The bars are spaced closely enough to form a narrow screening slot.
The outer surface of the screen is curved to fit the curve of the inner surface of the aperture bowl section. This feature helps prevent hard particle wedging.
The outer surface of the screen is also ground to clearance tolerances. The edges are also individually placed.
A lattice of crossing ribs typically forms the screen section of a screen bowl centrifuge. These bars are spaced in pairs to cover the full inner circumference of the aperture bowl section. This arrangement is termed the “lattice.” The cross-rib lattice is shaped to facilitate the passage of solids through the screen.
Typically, mechanical dewatering is associated with large wastewater treatment plants. The process separates sludge into solids and liquids. This can be accomplished using a combination of a chamber filter press, a belt filter press, or a centrifuge. However, the process does not treat the sludge and is usually used only for solids that are not hazardous.
To maximize the utility of a sludge lagoon, the solids are reclaimed. However, the use of sludge in the landscape is limited to applications that do not have a drying time constraint.
One method for utilizing a sludge lagoon is to agitate the sludge in a manner that reduces the effect of precipitation on drying the sludge. This agitation process is typically accomplished by pumping the sludge from the lower part of the lagoon into the surface. In the process, a crust is formed by excess evaporation over precipitation.
Another method for utilizing a sludge lake is to agitate the sludge using a sludge agitation vehicle. This device is typically mounted on a chassis with a swivel joint. It is equipped with buoyant propelling wheels that penetrate the sludge. The vehicle may weigh as much as 124,000 pounds.
A lateral discharge conduit is mounted on one side of the vehicle. This conduit may be a light conduit or a blower system. The conduit can follow the vehicle for significant distances.