Windrow turning

Finally, the Army conducted a study to examine the effectiveness of windrow composting. This study used cow manure, sawdust, and potato waste amendments and required the construction of a concrete pad leachate collection system. Temperatures were maintained at 55°C and the compost was turned once a day. This process produced 98% reductions of explosives contamination within twenty days, and degraded HMX,... 

With proper containment and manipulation of turning frequencies, windrow composting can be successfully implemented year-round. 

During composting, the contaminated soil must be periodically turned with flail-type windrow equipment to provide aeration. The rock debris in the contaminated soil decreases the operating efficiency of the equipment used to turn and aerate the soil. The rocks are thrown by the turning equipment, causing them to be potentially damaging projectiles. 

A recent U.S. Army study (performed by Battelle) identified, described, and evaluated technologies to facilitate remediation of oversize ex-plosives-contaminated debris. During composting of explosives-contaminated soil at military installations, such debris interferes with the operation of the flail-type windrow equipment used to turn and aerate the composting soil. The study examined size reduction and return of the crushed debris to the compost pile and removal of the contaminants from the debris followed by disposal of the cleaned debris. If the debris is to be returned to the compost pile, the particle size must be less than V2-inch diameter. For removal, the explosives contaminants level must be reduced to below 30 mg/kg. 

The wetted materials are then piled in a large rounded heap called a windrow. During this period the windrow can be turned and re-wetted as needed, usually 1 -3 times. 

For synthetic composts Turn and add more water. Break up any concentrations of supplements. Windrow. 

In the windrow method , compostable material is formed into elongated piles, known as windrows, which are turned mechanical on a regular basis. 

Mechanical—a method in which the compost is continuously and mechanically mixed and aerated. (2) Ventilated cell— method where compost is mixed and aerated by being dropped through a vertical series of ventilated cells. (3) Windrow—an open-air method in which compostable material is placed in windrows, piles, or ventilated bins or pits and occasionally turned or mixed. The process may be anaerobic or aerobic. 

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