Hay Dryer

Condensed from Capper's Farmer 1941
Farm hay drying has been made practical by equipment developed at the Tennessee Experiment Station. Rauth Brothers have installed the system on their farm in Warrick county, Indiana. It consists of a motor and fan set up on the outside with a series of ducts for distributing forced air thru the hay.
The main duct, 42 inches square, enters the barn midway of the side and extends to the center of the hay mow where it divides into 2 smaller ducts, one in each direction the long way of the barn. Every 4 feet along these branches, and at right angles to them, is a smaller duct,or upside-down trough, 6 by 12 inches. These lateral ducts are for distributing air and so are open on the bottom side which barely clears the mow floor. The whole distributing system is made of lumber, altho any other material, sufficiently rigid and inexpensive, presumably would be adaptable. Plans for the system were obtained from the Tennessee Station.
Hay is spread over the entire mow area in a layer up to a maximum depth of 6 feet, the first and second fillings.
The 4-foot fan, out of a coal mine ventilating system, and a 5-horse motor are housed in a simple lean-to-type shed set on pillars to afford ample air intake below the walls. Specifications were drawn to deliver 8 1/3 cubic feet of air a minute for every square foot of floor space. The assembly will deliver 20,000 cubic feet of air space a minute with the fan operating at 200 revolutions. If quick drying is required after a few days of muggy weather, a tractor is belted to the fan and the speed stepped up to 400 revolutions and the air delivery is increased to 35,000 cubic feet a minute.
"With this plant we are able to cut hay in the morning and put it up that afternoon, unless it is wet," said Mr. Rauth. "That means there is less chance of spoilage, we get a better quality of hay because there is no loss of leaves and fine stems, no bleaching and we preserve all the vitamins that the alfalfa contains at cutting time. That, in turn, means we have a better-quality product from the cows,one which is rich in he vitamins which milk produced from green feed contains. The hay cured in this way approaches pasture conditions as nearly as it is possible with a dry feed. So. in addition to a better product, we get a higher yield."
After the first 2 cuttings, the layer added each time is reduced in depth because drying is slower with the necessity for air to pass thru a greater volume of hay. But the thinner layers normally coincide with the size of later cuttings and so no delay is experienced in getting the hay under cover.
Ideal conditions after a fillig are hot days and low humidity. This insures quick drying and the motordriven fan will acccomplish curing without delay. But should damp rainy weather ensue after a filling, the moter and fan are kept going to cool the hay and prevent fermentation. Then the first dry day, a tractor is belted to the fan and the aerating is stepped up.
Although the system is quite satisfactory in its present form and fully justified, Mr. Rauth is considering and improvement by using artificial heat. A larger boiler will be installed in the bottling plant to supply winter heat also for his residence. "That same boiler we propose to employ in facilitating hay drying during summer if nesessary," he said. "With steam coils in the system, it should be possible to heat the air and thus increase its moisture absorbing capacity. Hereafter we expect to chop the hay."
Labor in handling hay in this way is estimated to be about the same as under orthodox methods. Although total weight is greater, turning, spreading and other efforts to hasten field curing are eliminated. Tennessee experiments indicate cost of drying is about 86 cents a ton. That, Mr. Rauth estimated, is about right for his conditions, and in view of the greater yield of leaves, the better quality, higher vitamin content, and milk-stimulating qualities, he considered the extra cost inconsequential. Under chopping he believed handling labor could be reduced somewhat and the effectiveness of a given tonnage increased. Further, the better-quality hay should enable him to reduce the protein concentrate allowance from other sources, particulary with the soybean silage he was providing.