Agitated Bed (Mechanical Windrow) composting is the making of long rows of compost by placing the organic material within low concrete walls (troughs) and mixing with a mechanized equipment. This process appears simple, but is very inefficient, mechanically intensive, and requires a very large area and building enclosure.

1. All of the material in the trough has to be moved daily to simply discharge a couple of hundred cubic feet of finished compost at one end.

2. The system is not very automated and normally requires front end loaders to load and unload a trough.

3. The same mixing /unloading device is used to mix contaminated sludge and later unloads finished compost. Bacterial recontamination potential is very real. (It's like mixing a sterilized batch with a dirty bacteria covered shovel).

4. Large amounts of needed process heat is released (as steam) during daily unloading/mixing, dropping temperature below 55 degrees C. daily, and making it difficult to maintain optimum composting temperature

5. All of the air within a very large building has to be collected and scrubbed. The energy required to operate the odor collection system is often more than compost process.
 
6. The environment inside the building on a cool day becomes a very dense fog; tough on operators and equipment.

* One (1) AirLance™ reactor is equivalent to three to four 300 foot long troughs.
* The AirLance™ system requires only 1/6th the land area.
* The AirLance™ system is 30 times more efficient. One of our unloading augers unloads at 6000 cubic feet/hour compared to the 200 cubic feet an hour of a mechanical windrow unloader.

Now let's take a look at some other concept flawed attempts to encapsulate (in-vessel) the composting process, starting with Rotating Drum Method.