Frequently Asked Questions about the Xact In-Vessel Composting System.

What sizes of BioReactors are available?

The BioReactor is available in 5’ to 10’ diameters and up to 60’ long. Determining the appropriate size of BioReactor is based on the volume of organic waste material and amendments to be composted.

How long does the waste remain in the BioReactor?

The time that the waste remains in the vessel is called retention time and this can vary depending on the type of waste to be composted. Typically, 4 days is sufficient to achieve compost that is about 75% mature (decomposed) and pathogen free.

Is a curing period required?

Upon discharge from the BioReactor, the compost is about 75% mature. In order to obtain maximum maturity, the compost should be cured for an additional 21 days or so (the length of time can vary). During this period, the compost should be sheltered.

How is pathogen-free compost achieved?

XACT Systems follows the EPA Rule Part 503 as a guide to it’s organic conversion protocol. These basic guidelines of composting are applied to any type of organic waste, which may or may not have the potential for human contact. Following these simple but precise guidelines will ensure the reduction of Pathogens, Viruses and Vector attraction.

EPA Rule Part 503

Viruses and pathogens can be reduced to undetectable levels through proper composting. In addition, vector attraction can be Temperature-probereduced to almost zero with proper composting techniques.

  • Within the vessel, the composting temperature must be maintained between 55°C to 65°C (131°F to 149°F) for 3


  • Demonstrate and meet a 38% reduction in volatile solids and/or maintain minimum temperature of 40°C (104°F) for 11 additional days.
  • Finished material test results show a Fecal Coliform count of < 1000 MPN/g.

Are there tests of the compost certified?

Absolutely. All raw material and compost testing is conducted by an independent lab such as A&L Labs, an international laboratory specializing in environmental and agricultural analysis.

Is heat added to the system?

No. The bacteria that are naturally living in the waste material generate the heat as a by-product of the decomposition process. The BioReactor is insulated so that heat is not lost to the ambient air.

Will the BioReactor work in sub-zero temperatures?

Yes. The heat that is generated by the bacteria is maintained because the vessel is insulated with 2” of insulation and if necessary an optional heater can be added to warm the air at the intake opening.

How does the BioReactor make compost so fast?

It does so by tightly controlling the factors that are needed for natural decomposition to occur. The reason being is that the vessel provides a perfect environment for the decomposition process by the naturally occurring aerobic bacteria to take place by controlling all the factors—moisture, oxygen, temperature, carbon and nitrogen—within the specific parameters that good composting requires (Mother Nature’s rules!).

What are Mother Nature’s rules?

  • Carbon / Nitrogen ratio must be within the range of 20 – 30:1.
  • Moisture content must be within the range of 60% – 65%.
  • Aeration of all material

Other factors to be considered are:

  • pH
  • Temperature
  • Bulk density

What sorts of waste can be composted?

Any solid organic material can be composted. Get in touch with us to discuss your particular organic waste challenges.

Yard litter, food waste, wood chips and any animal manure can be composted including biosolids.

What can I use the compost for?

Erosion control. Studies have shown that compost is great for controlling erosion of embankments and hillsides whether they are adjacent to roadsides, creeks, lakes or wherever—the stuff really works!

Soil amendment. Compost improves moisture retention capacity of soils, adds nutrients, and improves soil condition and structure. Scientific studies show that field soils show measurable benefits from compost—even after 8 years from the initial application.

Soil remediation. Organics conversion degrades volatile organic compounds, and many types of contaminants in soils, plus it binds heavy metals so they are not plant available. We can even help you produce “designer compost” specifically tailored to a particular pollutant. Call and ask us about this.

Animal bedding. Compost produced in the BioReactor is pathogen free, dry and provides maximum comfort and healthy bedding for any type of animal.

Flower beds, golf courses, park lands. Most gardeners would give their “eye teeth” for great quality compost that is weed seed free.

What are the benefits of using compost?

Compost Improves the Biological Chemical and Physical Properties of Soil Naturally!

  • Increase crop yields
  • Improves soil structure
  • Provides greater drought resistance and therefore more efficient water utilization
  • Modifies and stabilizes pH
  • Provides nutrients
  • Provides soil microorganisms and earthworms
  • Suppresses plant disease
  • Binds contaminants
  • Degrades compounds
  • Controls erosion
  • Controls weeds