Hiller Separation and Process

Decanter Centrifuges for Sludge Dewatering Applications - Water and Wastewater - Sludge Management

Diverse industrial applications for liquid/solid separation and sludge dewatering demand efficient and cost-effective solutions. Since its invention over 100 years ago the solid bowl centrifuge, also called a decanter, has established itself as conventional solution for this task across many sectors. The majority of these applications target the separation from the liquid and solid phase whereby, generally, the least possible residual moisture is required in the solid phase and the lowest possible solid particle residues are required in the separated liquid phase ("the centrate").

The advantages of the decanter are its wide range of potential use coupled with its continuous operation and ability to accept a wide range of feed concentrations within an equally wide range of feed capacities. The decanter centrifuge is very versatile and can be used for most types of liquid/solid separation dewatering slurries to a high level of sludge cake dryness. It can be used for the classification of solids in liquid suspension or for the clarification of liquids and recovery of valuable solids.

Municipal and Industrial Sludge Dewatering:

  • Reduces total disposal volume by as much as 70%+
  • Produces stackable cake like sludges with no free liquid
  • Reduces handling costs
  • Increases options for sludge disposal
  • Totally enclosed for odor minimization
  • Fully automated equipment operation with minimal operator attention required
  • Low maintenance
  • Continuous operation
  • Space saving: Small equipment footprint
  • No filter cloths or belts to maintain/replace

A typical example of this type of two-phase separation is the dewatering of sludge from municipal sewage plant or industrial waste water treatment. In this case, the residual moisture in the dewatered solids determines the disposal costs and the centrate quality determines the pollution load returned back to the treatment facility. Minimizing both must be achieved at the lowest possible cost, with the lowest possible polymer and energy consumption, with low maintenance costs and with the lowest possible number of required operating staff. In practice, the operator quickly realizes that there is no clearly defined operating point given daily and seasonal fluctuations; changes in system input or process configurations, as well as malfunctions of every sort always present new challenges that must be met.

This is where the Hiller DecaPress distinguishes itself particularly well, as it is very easy to set up while being extremely robust, stable, and reliable in everyday use, without the ease of use detracting from the quality of the operating results.

Advantages of DecaPress dewatering decanters compared to belt filter presses:

  • Fully enclosed machine = minimized aerosol emissions with less odor and corrosion
  • No filter cloth which is susceptible to clogging (fines, excess polymer, fats), and damage by debris contained in the sludge (e.g. pieces of wood or glass)
  • Minimized water consumption for washing / flushing only during start-up and shut down required, for only 10-20 minutes each
  • Very well suitable for soft biological sludges with good dewatering results
  • Continuous, fully automated 24/7 operation possible
  • Requires minimal operator attention
  • Smaller footprint

Advantages of DecaPress dewatering decanters compared to filter presses:

  • Fully enclosed machine = minimized aerosol emissions with less odor and corrosion
  • On filter presses often inorganic materials are added to aid filtration (e.g. ferric, or lime). This is often the reason for the high cake dryness of filter presses, but all this material adds to the cake quantity that needs to be disposed of. Decanters need polymer only.
  • No filter cloth which is susceptible to clogging (fines, excess polymer, fats), and sticking of cake
  • Minimized water consumption for washing / flushing only during start-up and shut down required, for only 10-20 minutes each
  • Continuous, fully automated 24/7 operation possible
  • Requires minimal operator attention
  • Much smaller footprint, not only in area, but also in required building height

The Hiller DecaPress DP decanter centrifuge series is an effective, low-maintenance solution to continuous liquid clarifying and / or solids dewatering with advanced process and mechanical performance features. The DP Decanter Centrifuges are very versatile and capable of adapting to a wide variety of sludge dewatering applications and capacities. And, the machines are easy to adjust over a wide range of process conditions and require little operator attention with automated controls. Learn More

Beyond manufacturing decanter centrifuges Hiller-US Separation & Process will also assist our clients regarding the optimal liquid-solid separation, sludge dewatering, or biological sludge thickening plant design and recommended choice of ancillary equipment plus implementation and commissioning of the entire dewatering and / or thickening plant.