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Bacteria Farming

There is no magic, no shortcuts. There is only MANAGEMENT. Composting is simply a mattter of making the indigenous bacteria very, very happy. If these bacteria are kept at their optimum environmental conditions (plenty to eat, good room-temperature, and lots and lots of fresh air) they will perform their natural work — making finished compost, in record time, without odors.

Windrow Dynamics

This is basically the natural, or unassisted, airflow and subsequent bacterial activity of an undisturbed windrow caused by heated air rising. The following diagram illustrates the concept of "windrow dynamics:" Windrow Dynamics

In the above illustration, Zone #1 represents what is referred to as "the dead zone", or the anaerobic spot that normally begins immediately in a newly formed windrow. Zone #2, which is the most active zone, is the hottest and has the most biological activity. This zone is the ideal zone —the "sweet spot" of composting. It is possible, however, to have temperatures rise too high in this zone, which will destroy befeficial bacteria. Zone #3 is the least compact zone in the entire windrow. It is cooler than Zone #2, but warmer than Zone #1. As the moisture evaporates and cool air penetrates, bacterial activity in this zone slows down rapidly.

Forming of the Zones

In most new windrows, other than straight yard debris, Zone #1 begins to form immediately and increases in size rapidly. What little oxygen exists is consumed rapidly, and the relatively high moisture content of the material begins to settle here. zone #2 is basically undefinable yet, but begins toform as a result of an active Zone #3, which remains small but active. If the row is not mised and aerated soon , it will all become Zone #1. This is the most critical point because the odors generated can be cause of complaints that ultimately close the site. These zones must be refreshed promptly. All the material must change places and, preferably, must change zones. This is accomplished by completely mixing and aerating the windrow, which is exactly what the Frontier windrow turner is designed to do.

Particle Size

It is widely known that bacteria work only on the surface of the material. The more surface area that can be exposed, the more bacteria the material can support. As the structural integrity of the material weakens due to bacterial activity, the vortex action of the Turborator™ breaks up the material into smaller particles, increasing the surface area and dramatically accelerating microbial activity. Smaller particle size adds to the value of the end-product, and golf courses and turf growers, for example, will pay more for < inch material. However, particle size should be be considered in isolation, since there can be problems unless the challenge of aeration is also addressed.

Air Flow

Virtually every study on odors shows a direct correlation between lack of oxygen and the presence of odors. Forcing air into the material is important. Keeping it there is vital. Unlike other turners on the market that actually squeeze the material like a sausage-maker, it is the patented throwing action of the Turborator™ itself that forms and shapes the discharge pile, not the shape of the tunnel. The front-to-rear airflow is shaped into two distinct counter-rotating vortices — one is spiraling from the left, and the other, from the right. The 18 ft. wide turner generates in excess of 35,000 CFM of fresh air while turning 2,000 - 4,000 CFM of material. That's over 15 times more air being moved than material!

100% Mixing is Critical

The third action of the Turborator™ is mixing:


The benefits of 100% mixing: