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Air Curtain Burners

An air curtain burner (ACB) is a device that burns wood waste, like trees and brush. An air curtain burner, also called an air curtain incinerator, carbonator, or mechanized burner operates by forcefully projecting a curtain of air across an open, integrated combustion chamber (fire box) or open pit or trench (trench burner) in which combustion occurs. [40 CFR 60.2970]

ACBs can be used for fire prevention efforts and wildfire cleanup. They can be an alternative to traditional open burning and produce less smoke and particulate matter. However, use of an ACB will require a permit from MBARD.

There are two types of air curtain burners: one produces biochar and one produces ash. Both are typically powered by a diesel engine that must meet the cleanest Tier 4 engine standards available on the market.

How does an Air Curtain Burner Work?

Diagram of a combustion system with high-velocity air for more efficient burning.

What is emitted from an ACB?

Compared to traditional outdoor open burning of wood waste, air curtain burners emit lower levels of air pollutants, including PM2.5 and nitrogen oxide. They burn more efficiently and produce significantly less smoke than traditional open outdoor burning.

What is required to use an ACB?

Only authorized materials can be burned with a permit in an ACB. Authorized materials are wood waste or yard waste. Depending on the location of the ACB, the materials being burned, and the quantity being burned, an ACB will require either a burn permit from MBARD or a stationary source permit from MBARD.  An important distinction for the permitting of ACBs is whether the device burns vegetation on the property where it was grown.

In addition, some uses can also trigger the requirement for a Title V permit per 40 CFR Part 60 Subpart CCCC. 

The following Air Curtain Burner Checklist can help with determining the requirements for your ACB project. Once the completed Air Curtain Burner Checklist is submitted, you will be contacted by a member of the MBARD Staff.


Potentially Applicable Rules and Regulations

Local Rules

MBARD Rule 428 Open Outdoor Fires

MBARD Rule 201 Sources Not Requiring Permits

MBARD Rule 1010 AIr Toxic Control Measure for Stationary Compression Ignition Engines

State Regulations

Airborne Toxic Control Measure for deisel Particulate Matter from Portable Engines Rated at 50 Horsepower and Greater

Federal Regulations

40 CFR Part 60 Subpart CCCC Standards of Performance for Commercial and Industrial Solid Waste Incineration Units

40 CFR Part 60 Subpart EEEE Standards of Performance for Other Solid Waste Incineration Units for Which Construction is Commenced After December 9, 2004, or for Which Modification or Reconstruction is Commenced on or After June 16, 2006