Dead Pig Composter

Big livestock operations all have a common problem. What do you do with dead animals? For the Puratone Corporation of Niverville, Manitoba, the answer was the Biovator, a mechanical composter that mixes carcasses with wood chips inside a revolving insulated tube. Turn it on for a couple hours per day. In 4 to 14 days, you have compost.

"You can push about 300 lbs. of livestock through per day," says Darrel Koop, manager, Puratone Equipment Division. "You can add more in a single day, but we don't put in more than 2,100 lbs. per week."

With 22,000 sows in the Puratone operation, passive composting just didn't cut it. And if you call a rendering service, you may be inviting disease to your farm.

"The most important component of composting is turning," says Koop. "In passive composting, the first weeks of turning are messy. We have four hog units with passive composters, each with four separate cells, concrete floors and a roof. If we get too much rain, we have a fly problem. If the heat isn't high, we get rodent problems."

With the Biovator, Koop and his co-workers don't have to worry about either turning the compost or keeping the heat high enough to kill bacteria and cook the carcass. Turning is accomplished by a 1 hp motor, which is more than is needed to do the job. As the tube turns, material is not only tossed, but also moved down the tube.

Heat is also not a problem. The insulated sides keep the heat produced by the decomposing carcasses inside. Koop reports that the temperature rises to 170F in the summer and 120F in the winter.

By the time the material has moved down the line to the end of the cylinder, it has become a high quality compost that can be used for flower beds, mulch or erosion control. Puratone tests every batch they make in their operation for contaminates, and so far the tests have all come up negative.

The Biovators come in 20, 30 and 40-ft. long, 4-ft. dia. units. The smallest Biovator is marketed most often to poultry operations. A 30-ft. unit is designed for farms with 6,000 feeder pigs or 1,500 to 2,000 sows with early wean barns. The 40-ft. unit is recommended for farms with more than 3,000 sows.

"We started three years ago, trying to build a mobile unit on the back of a truck," says Koop. "Now we have twelve 30-footers out and four more on the way. We cut our wood shavings costs to less than half of the old amount, and it only smells bad when the carcasses are first added. Within a day, there is hardly any smell."