Anaerobic Digesters


  • Cambi THP
  • Vaughan Rotamix
  • Cambi Solid Stream


Cambi Thermal Hydrolysis Sludge Pre-treatment

Cambi Thermal Hydrolysis Sludge Pre-treatment

Technology for Enhanced Anaerobic Digestion of Municipal and Industrial Sludge. Cambi’s Thermal Hydrolysis Process (THP) is a proven and reliable technology that has been used around the world since 1995. THP has been implemented in existing and “green field” projects designed to reduce disposal quantities and the cost of building and operating digesters.

Cambi THP is a high-pressure steam pre-treatment for anaerobic digestion of municipal and industrial sludge and bio-waste. Applying THP technology results in:

  • Doubled digester loading
  • Increased biogas production
  • Pathogen-free and stabilized biosolids product with increased cake dewaterability

The production and quality of the resultant biosolids save transport and energy costs as well - the end product can be applied directly to agricultural processes or composted or dried for use as fertilizer or bio-fuel. In addition to optimizing energy-efficiency and lowering operating costs, THP also eliminates odour problems associated with the treatment of organic materials.

Cambi THP plants can be combined with cogeneration plants, which produce green electricity and provide hot steam for the Thermal Hydrolysis Process. Resultant biogas can also be cleaned for use as vehicle fuel or as a replacement for natural gas.

Cambi offers a variety of products and services from our core THP technology to complete turnkey digestion plants. We also possess the skills and expertise to oversee plant operations and maintenance. Our THP plants normally treat sludge from wastewater treatment plants for populations over 100,000 people, or over 3,000 metric tons/year of sludge. Cambi’s THP enhanced sludge treatment maximises both flexibility and profitability.

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Cambi - BioSolids Cambi - BioSolids (793 KB)



The Rotamix® System


Principles of Theory

The Rotamix system incorporates several basic principles of physics and hydraulics, including uniform and vortical fields of flow, induced flow and surface contact. Combined together, this unique mixing system optimizes solids contact due to the homogeneous state.

Dual-Zone Mixing

The Rotamix dual-zone mixing pattern is a combination of both uniform and vortical fields of flow. In a uniform field of flow, the entire contents rotates as a solid unit with the highest velocity at the outside. In a vortical field of flow, fluid velocities are the greatest at the center, thus creating a vertical-axis vortex. The Rotamix system combines both uniform rotation (ZONE 2), and a vertical-axis vortex (ZONE 1), creating unique dual-rotational zones.

High Velocities

With dual-zone mixing, average velocities are higher and more steady. Solids are also prevented from settling in the center.

Induced Flow

High velocity nozzles also increase the effective mixing volume by inducing entrained fluid, thus significantly increasing the overall mixing effect (see Figure 2). High velocity nozzles induce flow over a long distance, thus generating an overall effect over a large volume.

Surface Contact

The Vaughan chopper pump not only eliminates nozzle clogging, but also optimizes surface contact by constantly reducing solids size, thus increasing total surface area.



Wastewater Applications:

  • Anaerobic Digesters
  • Egg-Shaped Digesters
  • Sludge Storage Tanks
  • Sludge Blending Tanks
  • Influent Channels
  • Equalization Tanks
  • Secondary Digesters
  • Aerobic Digesters w/ Aeration
  • Alum Sludge
  • Lime Slurry Storage
  • Lime Stabilization
  • Anoxic Zone Mixing
  • Septage Waste Haulers
  • CSO Tunnels
  • CSO Retention Basins
  • Ground Storage Tanks





Cost Savings

When compared to conventional mixing systems, the Rotamix system can save up to 60% in combined capital, operation and maintenance costs.

Complete Mixing

Multiple nozzles allow effective mixing energy distribution, eliminating the need for rotating nozzles. By using the Vaughan chopper pump, surface area and subsequent organic breakdown is maximized.


  • Ability to intermittently mix tanks after long periods of storage, offering power savings
  • Allows intermittent operation of conventional process systems, reducing energy costs


  • Fixed dual rotational pattern makes rotating nozzle designs obsolete
  • Vaughan Chopper pumps virtually eliminate problems with fibrous material and other debris, while ensuring pumps remain clog-free
  • Efficient mixing optimizes chemical consumption in sludge dewatering applications
  • Operates without liquid level dependency
  • Meets or exceeds high rate digester designs

Minimal Maintenance

  • No scheduled nozzle assembly maintenance required
  • No rotating equipment within the process
  • Reduces confined space entry into tanks for maintenance


  • Ability to mix multiple tanks, using only one pump
  • Ability to fill, mix and transfer using only one pump
  • No access walkways, platforms or hoists required
  • Complete installed Rotamix system typically costs less than equipment alone for other types of mixing systems
  • Potentially reduces cost of aeration equipment
  • Easily retrofits into existing tanks
  • Ability to work with flat floor design reduces construction costs

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Vaughan: Rotamix Vaughan: Rotamix (7777 KB)




Cambi SolidStream

Cambi SolidStream™ is a patented Cambi process for existing and green field plants. After conventional digestion, biosolids (treated sludge) typically dewater to 20-25% dry solids, which means 75-80% of the further costs for transporting and handling are associated with the water.

By increasing dewaterability of digested solids to 40-60% dry solids, the water volume and associate costs can be reduced by 75%. In addition, Cambi SolidStream™ results in a Class A, pathogen-free product.


  • Dewatered, digested sludge is fed to SolidStream™ process at 17% DS

  • Sludge is treated at high temperature and pressure in pumpless pressure cooking process

  • Hydrolized sludge is dewatered at elevated temperature (100 ºC) without polymer

  • Dry Sludge Cake (> 60% DS) is cooled with air

  • Cooling air is scrubbed to remove odour components

  • Dewatering centrate and process gas are highly concentrated sources of biodegradable material and are returned to the conventional digester for additional biogas production


  • Volume Reduction

  • Long term stable sludge treatment and disposal cost

  • Savings in polymer consumption (dewatering only to 17% DS)

  • Increased electricity production footprint of wastewater operation

  • Reduction of carbon footprint of wastewater operation

  • Ideal, multi-functional end product:

    • A "class-A" biosolids product

    • An autothermic bio-fuel

    • Good in structure and low on water, beneficial for soil production

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Cambi - Solid Stream Brochure Cambi - Solid Stream Brochure (2345 KB)