Dead Poultry Composter Project: David Boyd Composter
Charles D. Fulhage
Department of Agricultural Engineering
A grant of EPA funds was made available by the Missouri Department of Natural Resources in October 1990 to selected southwest Missouri poultry producers representing each of the five major poultry processing companies. The purpose of the grant is to demonstrate the feasibility of composting dead birds in an environmentally sound manner. The grant is administered by Southwest Missouri Resource Conservation and Development, Inc., with technical assistance provided by the Natural Resources Conservation Service and educational activities provided by MU Extension.
David Boyd, of Purdy, Mo., representing George's, Inc., agreed to participate in the demonstration project. Boyd's concerns about environmental considerations and future regulations pertaining to dead bird disposal were factors in his decision to participate in the project. This guide describes the composting project relating to Boyd's poultry operation.
The Boyd broiler operation consists of five buildings in which 6 flocks per year are grown to a market weight of 4 pounds. Table 1 outlines the characteristics of the five buildings. Average mortality rate in these facilities is about 3 percent.
Building type and bird capacity in the Boyd operation
||Number of birds
||Time in buildings
The composter serving this operation has several unique construction features:
- Straight-leg steel frame trusses on 10 foot spacing, which provides a clear span of 40 feet with maximum headroom.
- Primary and secondary bin walls of treated lumber supported by 4-by-6 treated posts set inside the centerline of the steel truss legs. Posts and walls are 5 feet high.
- A dedicated litter storage area at the rear of the composter. Walls in this area are made of 2-inch treated lumber and are 5 feet high. The walls are supported laterally by 2-by-6 treated studs on 2 foot centers, which extend from the concrete floor to the eave line. Along the rear wall, the walls are supported by 4-by-6 treated posts on 4 foot centers. These posts extend to a height of 5 feet above the concrete floor. A portion of the end wall above the posts is framed with 2-by-4 studs on 2 foot centers. Corrugated sheet metal protects this portion of the building end wall to the litter storage area from rain.
Figure 1 shows the steel frame truss used to support the roof. These trusses are bolted to the perimeter footing of the building.
Primary and secondary compost bins are located along the outside front walls. There are three primary and secondary bins in the facility. All bins are the same size (8 feet wide, 6 feet long and 5 feet high) with a capacity of 240 cubic feet each. Total capacity is 720 cubic feet in the primary bins and 720 cubic feet in the secondary bin.
This layout provides a large covered work area (24 feet by 27 feet). Corrugated sheet metal partially encloses the top of bin walls and the eave for rain protection. Primary and secondary bins are made with 2-inch treated lumber, allowing 1-inch spacing between boards for air movement.
The rear portion of the composter is used as a litter storage area. This area is 39 feet wide, 20 feet long and 5 feet high. Volume for the litter storage area is 3,900 cubic feet — 60 tons of litter storage space. This volume is greater than the volume of litter used annually in the composter, hence in excess of one year's storage of litter is available in the composter building. Additionally, the large litter storage area adds flexibility to the production building clean out and land spreading schedule. The litter storage area has 5 feet high walls supported by 2-by-6 treated wood studs on the sides and 4-by-6 treated wood posts along the back. The gable area of the back wall is enclosed with 29-gage corrugated sheet metal attached to 2-by-4 studs that rest on a plate at the top of rear wall posts.
Figures 1 through 5 show construction details of the Boyd composter.
Plan view of the Boyd composter.
Cross section of the Boyd composter through the composting bins.
Cross section of the Boyd composter through the litter storage area.
Side view of the Boyd composter.
Rear-end view of the Boyd composter.
Boyd estimates an average of 30 minutes per day is spent layering dead birds and ingredients in the composter. Boyd says he prefers the composter method of dead bird disposal over his former method of pit burial.
He uses a 60 hp tractor with a 6-foot bucket on a front-end loader to move and load compost. Finished compost is spread by a hired contractor. He noticed that compost containing excessive straw is difficult to handle with his loader. Table 2 shows a laboratory analysis of the finished compost fertilizer value from the Boyd composter.
Analysis of litter and finished compost in the Boyd operation
|Dry matter (percent)
|Nitrogen (pounds per ton)
|Crude protein (percent)
|P2O5 (pounds per ton)
|K2O (pounds per ton)
Composter costs depend upon many factors such as site characteristics, composter design, size, etc. Table 3 shows costs incurred for the Boyd composter as constructed in November 1990.
Cost associated with the Boyd composter (November 1990)