Sludge dewatering refers to the process of water removal from sludge. After treatment of wastewater, the material remaining usually has a significant amount of water content, necessitating the final step of reclaiming much of the liquid. The process of handling and disposing of sludge translates into a major cost for facilities of wastewater necessitating the need for contract dewatering. Innovative alternatives and improvement to old methods used at treatment plants. Some of the options are listed below.
Popular dewatering options
Belt filter presses
Having been around for quite some time, it is an old type of equipment but is still considered to be among the industry standards. They are very familiar to a majority of the facility staff and are very easy to operate. The only downside to belt filter presses that they are not so effective in containing odor.
Centrifuges have been used in the process of sludge dewatering for quite some time now, all along experiencing some significant improvements. They are usually quite fast, running at about 3000 revolutions per minute. This means that regular maintenance is necessary for them. However, they are built for smooth operation and reliability.
Typically, they produce the driest cake, which means that they remove the highest amount of water. Odor control is also taken care of thanks to the fact that they are self-contained. A centrifuge is flexible and can handle various changing conditions. It works so well in any treatment application.
Rotary disc press
This method is relatively new. It involves two rotating screens where the flocculated material is fed within the disc assemblies. Each equipment can have up to 6 discs per unit. The entire system is also self-contained, and the slow rotation seems to be liked by users.
Inclined screw press
Just like the rotary disc press, flocculated material is fed into an inclined screw. The screw rotates inside a wedge wire screen made of stainless steel. It is self-contained with the operation speed also being very slow. Compared to other methods, it uses the least amount of power.
Horizontal screw press
This system is more or less similar to the inclined screw press, the main difference being that flocculated material is fed into a rotating screen that is placed horizontally. It is a good option for dealing with larger quantities. Traditionally, they were used in paper and pulp industry but recently they find their application more in the wastewater treatment plants.