Bioforcetech Biodryer

Technology Description

Aerobic Biological reactor for biosolids that creates optimal conditions for bacterial growth. The exponential growth of bacteria within the reactor releases heat, drying the biosolids. Conditions within the reactor are controlled by AI. In addition, BioForce Tech pyrolizes dry biosolids to create syngas for clean energy generation and biochar, a sustainable soil amendment.

Technology Stage

Pre-Commercial (proven technology, not yet widely adopted)

Technology Application(s)

On-site drying of biosolids and resource recovery

Replaces traditional biosolids drying technologies such as gravity belt thickeners and screw presses

Reduces energy input and environmental risk for management of biosolids

Prepares biosolids for energy generation, either in anaerobic digesters or BFT pyrolysis reactors.



Technology Benefits:

  1. Builds drought resilience:
    • Addition of biochar to soils decreases bulk density, increases total pore volume, and increases available water content in a wide variety of sandy soils, which are common in Tulare County.1
    • Biochar increases the drought resistance of fungal and bacterial communities within soil due to faster recovery from disturbances.2
  2. Supports electric reliability:
    • Reduces heat consumption (thousand BTU/ton) by 70% over conventional gas dryers.
    • Reduces electric consumption (kWh/ton) by 50% over conventional gas dryers.
    • Increases renewable energy production Pyrolysis produces syngas, a clean, renewable fuel that can be burned for energy. The energy savings of BFT’s biodryer and energy production of syngas can reduce energy required for biosolids management by up to 100%.
  3. Reduces greenhouse gas emissions:
    • Production of “Integrated Distributed Energy Resources” (IDER: energy efficiency, demand reduction, distributed renewable energy production) all reduce greenhouse gas emissions:
      • Reducing natural gas usage which is primary activity of this system will reduce GHG emissions on a net basis
      • Reducing electric use and electric demand reduce production and/or purchase of marginal electric resources, much of which is produced by natural gas.
      • Increasing production of distributed renewable energy reduces electric transmission losses and enhances ability to reliably integrate increasing quantities of intermittent renewable energy resources
  4. Reduces greenhouse gas emissions:
    • Up to 90% volume reduction, which reduces the number of trucks required to transport biosolids by 90%.
    • Efficient capture and treatment of biosolids at the source reduces escaped methane emissions
    • Biochar has a high carbon content and doesn’t biodegrade, so it permanently sequesters carbon within soil, increasing soil carbon content by 34%
    • Biochar Reduces CO2, CH4, and N2O flux of the soil, reducing agricultural greenhouse gas emissions3
  5. Reduces ratepayer costs:
    • Automation, limited moving parts and high-quality material design reduce operation and maintenance costs by (X).
    • Modularity of systems reduces costs, extends life, and reduces need for expensive, long lead-time retrofits of large centralized wastewater treatment systems, which reduces costs of wastewater collection and treatment for all customer classes
    • Potential creation of new revenue sources from biochar and syngas allow facilities to invest in more upgrades without relying on rate increases.
  6. Reduces regulatory and environmental risks:
    • Pyrolysis eliminates pathogens, pharmaceuticals, and chemicals of emerging concern in biosolids.
    • Volume reduction reduces overflow risk of sludge beds, and prevents surface and groundwater contamination.

2 Liang, C. et al. Biochar alters the resistance and resilience to drought in a tropical soil
3 Liang, C. et al. Biochar alters the resistance and resilience to drought in a tropical soil


Current Status

Technology has been successfully installed and benefits documented at 1 of facility:

  • Silicon Valley Clean Water (2015). In September 2015, BioForce Tech signed a contract with Silicon Valley Clean Water (WWTP) for the energy recovery and biochar production of 7,000 tons of biosolids per year. The biochar production is estimated to be around 700 tons per year.
    • 03/17 – received the first ever permit for a full-scale pyrolysis plant to transform biosolids into energy and biochar
    • Nutrieno Biochar tested – showing increase growth rate of tomato plants by X%

Data provided by Dario Presezzi, BioForce Tech