They're Using Liquid Hog Manure As Compost Wetting Agent

They're Using Liquid Hog Manure As Compost Wetting Agent FERTILIZER APPLICATION Fertilizer Application (58f) 22-3-40 Composting is an efficient way of disposing of solid livestock manure. But what about liquid manure? One researcher says it can be used as a wetting agent for solids in place of water. Paul Walker is an animal scientist at Illinois State University in Normal, Ill. For two years, Walker and his associates have been experimenting with applying liquid hog manure to composted yard waste and solid beef and dairy manure. "It takes management and a little extra time because you have to haul and turn, haul and turn, but it looks like a very effective ælow odor' way of disposing of the liquid," Walker says. To apply the liquid evenly to the university's 5-ft. wide by 4 to 5-ft. tall wind-rows, the researchers modified a conventional 2,250-gal. Balzer honey wagon equipped with rear discharge and front suction fill. "We installed a 4-in. dia. hydraulic discharge valve on the suction pump and fitted the end of the valve with a shroud we built out of sheet metal," Walker says. "That's to keep the liquid within the 5-ft. area of the windrow instead of spraying out beyond it." Rates average 1.35 lbs. of liquid manure to 1 lb. of compost, or 498 lbs. to the cu. yd., Walker says. "In summer we use it as a wetting agent, typically applying it once a week," he says. "In fall and winter we add just enough liquid to keep our carbon-nitrogen ratio at the desired 25 to 30 to 1 level. "We've learned you can apply only so much liquid before you have to turn the windrow. Otherwise, it saturates the outside of the pile and rolls off. Also, if it's not turned within 12 hours, it'll stink to high heaven. But there's nothing more than the normal compost odor once you've incorporated it." During the first nine months of the experiment, the researchers applied 2,800 tons of liquid manure to 2,080 tons of compost, which produced a final total of 2,250 tons of compost. It was used as agricultural fertilizer on the university's fields at rates of up to 60 tons per acre. "It's all based on science, but there's a certain amount of art involved, too," Walker says. "For example, how do you manage during less-than-ideal conditions like the tremendously wet weather we've been having lately?" An economic analysis of the practice is just beginning, he says. Contact: FARM SHOW Followup, Paul Walker, College of Applied Science and Technology, Illinois State University, 150 Turner Hall, Campus Box 5020, Normal, Ill. 61790-5020 (ph 309 438-5654; fax 5037).

To read the rest of this story, download this issue below or click here to register with your account number.