Catch Those Cobs

December 12, 2008 06:00 PM
If there is one word to describe the burgeoning industry of corncob harvest and collection, that word would be "options.”

"The goal is to make corncob harvest as seamless for farmers as possible, so we are researching lots of options for any size of operation,” says Scott Weishaar, director of business development for Poet, which plans to make cellulosic ethanol from corncobs at its Project Liberty ethanol facility in Emmetsburg, Iowa, starting in 2011.

The Poet team is working closely with more than 10 farm machinery companies to develop equipment that can harvest, collect and transport corncobs from the field to field's edge.
It's important that farmers realize Poet is not asking them to store corncobs, just to harvest the cobs and pile them at the end of the field, Weishaar says. Poet will then pick up and transport the cobs to its cellulosic plant in Emmetsburg for processing.

The ethanol producer estimates it will pay between $30 and $60 per ton for cobs. Government incentives and legislation written into the farm bill may also increase the price farmers could be paid for cobs.

Three systems. So far, equipment companies have showcased three methods for collecting cobs.

The first is called corncob mix, or CCM, where combine modifications allow for the corn and cobs to be collected together in the grain tank, transferred to grain carts and separated by trammel screens. Cobs are then piled at the end of the field for collection, and grain is transported to market.

The combine manufacturers that are involved in the CCM method of harvest include Case IH, John Deere and Claas Lexion. Unverferth and Demco, grain cart manufacturers, and Wildcat, the manufacturer of trammel screen systems for cob separation, also have CCM harvest equipment.

"The CCM method requires the least amount of investment in cob collection equipment,” Weishaar says. However, it does necessitate extra equipment for separating out the cobs. Farmers may want to join together to buy separation equipment.

A second harvest method is whole-cob collection, which uses a towable cob cart behind the combine. The combine's chopper is disengaged, and the cobs coming out of the back of the combine go on a belt that carries them to a separation process. Then, cobs go into the cob cart and non-cob stover blows back onto the field.

With this method, the combine has no modifications except for in-cab monitoring and control of the cob cart. Several technologies are in development for towable systems to separate the cob and put the stalks and husks back out on the field, Weishaar says.

Manufacturers working on towable cart systems are Case IH, Vermeer Manufacturing and Redekop.

"The towable system lends itself to farmers who don't have much available labor because the separation process is done within the towable cob cart and farmers can just dump cobs at the end of the field,” adds Sam Acker, director of harvesting marketing for Case IH.

A third system under development is a joint effort by Iowa State University researchers and John Deere. It involves modification to a John Deere 9770 STS combine with a forage chopper–style unit mounted on the rear of the combine. With this system, the combine functions as normal, but instead of cob and stover going out the back of the combine and onto the ground or into a towed cart for separation and collection, the forage chopper chops the cobs and blows them into a trailing forage wagon.

Once harvested, there are several options for transporting cobs.

Unverferth has developed the Brent Avalanche 1194 CCM dual-auger grain cart, which is designed to quickly unload and move CCM from the combine to waiting trucks or separating units. The Demco 1050 grain cart also handles the CCM mix effectively.

Besides its CCM cart, Demco has created the 2-SKU grain and cob transportation cart, which receives both grain and cobs from the combine in separate sections but requires only one operator. The combine off-loads grain into the first compartment, and an attached second Demco cart swings around to allow the cob harvest machine to dump its contents into the second compartment on the cart.

Claas is working with Trail King trailer manufacturer to develop a special toolbar hitch so that a semitrailer can be pulled with the Claas Xerion into the field for cob transport. Because weather can be volatile at harvest, the combination of using a large tractor with plenty of horsepower and a semitrailer allows the producer to move a lot of cobs out of the field easily, Weishaar says.
Other manufacturers involved in Project Liberty include Fantini North America, which builds harvesting heads for combines, and MachineryLink, a combine leasing firm.

Near commercialization. The equipment at Project Liberty is still considered prototype, but some equipment is close to commercialization.

Vermeer, for example, conducted test harvests throughout 2008 to evaluate performance and efficiency and plans to have its product available to farmers for the 2009 harvest season, according to Vermeer segment manager Jay Van Roekel.

"Right now is the time for farmers to let us know if they want to harvest cobs for Project Liberty in 2009,” says Jim Sturdevant, director of Project Liberty. "This is our call to action.”

Equipment for Cob Harvest and Collection at Project Liberty

Brent Dual-Auger Cart
Unverferth Manufacturing's Brent Avalanche 1194 CCM dual-auger cart is specifically designed to move corncob mix from the combine to waiting trucks or separating units and back to the combine quickly and efficiently.

The cart features an exclusive drivetrain design that combines a belt drive for the floor auger and a heavy-duty direct drive 90° gearbox for the vertical auger to quickly
unload its 1,100-bu. payload. For optimum unloading ease, the cart features a pivoting unloading auger with more than 5' of hydraulically controlled height adjustability.

Case IH Cob Harvester
The prototype Case IH cob cart trails behind select combines, such as the Axial-Flow 8010. Cobs, husks and stalks come out the back of the combine and go onto a belt that carries the mixture into a separation process that expels the non-cob material. Cobs are delivered into the cob cart, and clean grain is delivered to the combine grain tank.

Modifications to the combine's power system are required to power the cart, conveyer belt and separation device. Controls are in the cab to operate the cob cart and the unloading system. A special hitch on the combine tows the cart.

Claas Xerion and Trail King Trailer Adaptor
Claas of America and Trail King Industries have developed a prototype steel detachable gooseneck adaptor that can be used to hook a modified semitrailer for corncob transportation to the ball coupling on the Claas Xerion Trac VC tractor.

The Xerion's horsepower allows it to bring a semitrailer for cob collection to the combine in the field. The ball coupler is located high on the back of the machine behind the cab so the weight to increase traction comes from the trailer. A majority of the trailer weight rests on the four large tractor tires.

Demco 2-SKU Grain Cart
Demco's 2-SKU grain/cob cart works with a combine to harvest corn into its grain tank and cobs into a cob harvest machine pulled behind the combine.

When the combine is full, it unloads corn into the main Demco grain cart. An attached second Demco cart then swings around to the side to allow the cob harvest machine to dump its contents into the cob cart. At that point, one operator can haul both carts to the edge of the field for unloading grain and cobs. All operator functions of the Demco 2-SKU cart are performed from the tractor seat.

Redekop Cob Harvester
The prototype Redekop cob harvester is towed behind select combines. Cobs, husks and stalks that come out the back of the combine go onto a belt that carries the mixture into a separation process. Air is used to separate the cob from the stover, and husk and cobs are delivered into the cob cart while non-cob material is pushed out on either side of the cart.

Built by the Canadian company Redekop Manufacturing, the system has a rear discharge that
allows the operator to put cobs into a transport cart or discharge cobs in a pile at the end of the field.

Vermeer CCX770 Cob Harvester
Vermeer Manufacturing introduces the CCX770 cob harvester, a new wagon-style cob collection system that tows behind select corn harvesting combines to collect and unload cobs. Hitching is easy with a hydraulic-controlled tongue; the only combine modification needed is adding the OEM-approved hitch. 

The self-contained machine has a patented separation process that distributes the husks and leaves back to the field and the cobs into the dump box, which holds 4 tons. The CCX770 allows for unloading into a truck, wagon or storage pile.

u can e-mail Jeanne Bernick at

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