Aerated Static Pile or ASP systems have been the standard for providing aeration to active compost piles for over 40 years. The ASP concept is simple: Place perforated pipes on the ground that are connected to a blower to push (positive) or pull (negative) air through the compost. First cover the pipe with some wood chips to distribute air and then carefully build a well mixed and watered compost pile six to ten feet deep and then cap it with a layer of old compost or wood chips to insulate and remove odors from the surface.

ASP piles generally stay in place for about 14 to 28 days until temperatures drop or their moisture levels become so low as to limit effective composting. At this point, the pipes are pulled out by a loader and the compost is cured and screened for sale. GMT also offers below grade piping systems that substantially reduce the labor associated with setting up each pile. Tarp systems can be used during wet weather to prevent saturation or to limit vector access to the compost.

WHAT FEEDSTOCKS COMPOST WELL WITH ASP?
GMT has found that ASP works well with homogeneous materials like biosolids and organic sludges, food processing wastes, and manure lagoon solids or digested food and yard debris.

HOW DO YOU DESIGN AN ASP SYSTEM?
Efficient design of the piping system is critical for even distribution of air in a compost pile. The selection of above grade versus below grade piping has long term impacts on operational efficiency as well as near term capital costs. GMT has over 20 years of experience designing ASP controls and aeration systems and is available to help you build a successful ASP system.

HOW DO YOU CONTROL THE PROCESS?
Temperature feedback is the best way to regulate an ASP system. Turning on the blower will cool the compost, removing excess biological heat while adding oxygen to the pile. Too much aeration over-cools the pile and slows the process down. GMT offers two blower control systems that automatically regulate the aeration system using temperature feedback. The CompDACS controller for PC interfaces and the WebMACS system for browser access from any web enabled device.