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Waste Receiving Area

When the raw waste stream arrives at the composting facility, it is unloaded into a large, fully enclosed waste pit. Liquid wastes are unloaded into a tank which can then be pumped into the Bioreactor as process water. The raw waste is then lifted from the pit by a grapple and overhead crane, and fed into the Bioreactor. This waste "feedstock" can be loaded into the Bioreactor for up to twelve hours per day.

Central Control Room

This entire operation is carried out from a Central Control Room overlooking the waste pit and receiving area - all within an air conditioned room. Programmable logic controllers and automated video equipment allow the operator full control over the entire composting process. As few as three people can operate the entire system.

Bioreactor

The Bioreactor, which rapidly breaks down organic material into raw compost, is the key to the accelerated maturation process. The feedstock remains within the continuously rotating Bioreactor for a minimum of three days. The result is a mixture of biodegraded organic matter and non-compostable residues. Due to the high temperature achieved in the Bioreactor, this material is free from harmful pathogenic bacteria.

Primary Refining and Sorting

After leaving the Bioreactor, the composted organic matter is separated and transported to the Maturation Building for further processing. The residue, which contains non-compostable material, is directed to a sorting section where the recyclables are recovered and non-organics are compacted into containers to be transported for disposal.

Maturation Building and Secondary Refining

The recovered compost is mechanically placed into windrows between concrete walls. The compost temperature and moisture content are controlled by force aeration, water addition and regular turning of the windrows. After several weeks, the compost is transported to the secondary refining area to achieve a homogeneous compost, which can easily be mixed with soil.

Odor Control

An odor control system captures and conveys all air from inside the buildings to a biofilter. The biofilter is constructed in multiple cells which normally work in parallel, but may be isolated for repair while the others remain in operation for odor control during the maintenance period. The effectiveness of this system can be experienced by a visit to our Tracy Facility and talking with our neighbors.