In-Vessel Tunnels

Systems ECS Staff 07/29/2021

ECS offers the only In-Vessel Tunnel-type composting system developed and built in North America.  This technology offers the ultimate in Best Management Practice compliance, odor and leachate control, and below freezing cold weather performance.

Their sealed, well-drained, and highly controlled aeration allows them to reliably manage less-than-ideal feedstock mixes without creating nuisance odors.  Their unique level of thermal control provides rapid heating of cold loads and very uniform temperatures throughout the pile to insure the Process to Further Reduce Pathogens (PFRP) is quickly and reliably achieved. Additionally, the robust design and construction of ECS’ In-Vessel Tunnels means that they will last for decades.

in vessel composting system
in vessel composting system
in vessel composting system
conveyor loading compost vessel

The ECS tunnel-type in-vessel composting system provide the ultimate in process and environmental control for facilities that are odor sensitive, have challenging feedstocks, and need weather-proof rapid bio-stabilization rates. This system is an ideal choice when composting operations must be fully enclosed as it both minimizes both the facility footprint and greatly reduces the volume of room air that must be handled, heated, exchanged, and scrubbed.

Standard Features:

  • Excellent odor control with completely sealed design and the ability to exhaust all air through a scrubbing system.
  • Highly efficient aeration system that rapidly heats up low energy feedstocks and minimizes fan power.
  • Robust concrete and stainless steel construction for a 20+ year service life
  • Built-in condensate/leachate management system
  • Fully automated aeration control and process monitoring
  • Rugged light-weight doors with motorized carriers


The vessels are made of concrete that is either site-poured or panelized. Vessel sizes vary to conform to the client’s site and process. The vessel walls and ceilings are well insulated; doors are fully gasketed,
weatherproof, and insulated. All door surfaces exposed to the process air are stainless steel. The aeration floor provides uniform air distribution. Condensate/leachate is collected in the aeration floor and drained to a sealed sump.


The aeration system provides reversing and recirculating process airflow to control and maintain uniform BMP compliant temperatures and oxygen levels. Process air is exhaust air which is typically scrubbed through an ECS designed biofilter. All components in contact with the compost’s corrosive airstream are made from either stainless steel or polymeric materials. The aeration system is designed to conserve energy with variable speed fans, a unique low-friction aeration floors, and adaptive control strategies. Motorized dampers control airflow and direction to each vessel. Damper positions are automatically set by the control system.


ECS’ CompTrollerTM is an automated aeration control and monitoring
system that is operating at all ECS compost installations. It is designed
to achieve regulatory compliance; offers operators a broad range
of process options; and provides each vessel with independent and
automatic control for achieving process goals. The CompTrollerTM is
remotely accessible via the web and is flexible, robust, and keeps your
data safe.