Location: National Peanut Research LaboratoryTitle: Unloading farmers’ stock warehouses with a peanut vac
Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/21/2018
Publication Date: 10/3/2018
Citation: Butts, C.L., Sorensen, R.B., Lamb, M.C. 2018. Unloading farmers’ stock warehouses with a peanut vac. Peanut Science. https://doi.org/10.3146/0095-3679-45.2.87.
Interpretive Summary: A peanut vac is a pneumatic conveying system used to move inshell peanuts from a storage facility into a truck for transport to the peanut shelling plant. The system is powered by the power takeoff (PTO) of a tractor that transmits the required power to a blower. A flexible pipe is connected to the intake of the blower. When the end of the intake pipe is inserted into the peanuts, the blower pulls air and peanuts through the intake tube and into a cyclone separator. The air velocity is reduced so that the peanuts drop out of the air stream into the bottom of the cyclone separator. The air continues to a second cyclone separator where the finer material such as dirt drops out of the airstream prior to the air continuing through the blower. The air then continues through a discharge chute below the first cyclone separator where an airlock valve is rotating and drops the peanuts from the cyclone into the discharge airstream. The peanuts are blown up the discharge chute and into the waiting trailer. Tests were conducted to compare the rate at which the peanuts could be loaded into the trailer and the damage caused by pneumatically conveying them to the conventional method of loading a truck. This research showed that the pneumatic conveyor could be used creating less mechanical damage than using a conventional front-end loader and conveyor belt to load in-shell peanuts into a truck. While considerably slower than the conventional loading method, the pneumatic conveyor could load approximately 23 trucks per 8-h day which may be adequate for many situations.
Technical Abstract: A peanut vacuum was developed by redesigning an existing grain vacuum (vac) specifically to handle farmers’ stock peanuts accounting for the desire to maintain the integrity of the peanut pod throughout the conveyance process. The peanut vac consists of a PTO-driven positive displacement blower, two cyclone separators, and a hydraulically-powered airlock valve. The blower pulls air and farmers’ stock peanuts through a length of suction hose into the first cyclone separator where the peanuts are separated from the airstream. The air then travels to a second cyclone separator where the suspended dirt and other fine particles are separated from the airstream. The cleaned air proceeds through the blower and is blown through a discharge chute beneath the outlet of an airlock valve mounted on the bottom of the first cyclone. Farmers’ stock peanuts from the first cyclone fall from the outlet of the airlock valve into the airstream in the discharge chute and are conveyed up into a waiting trailer. The peanut vac is powered by a 1000-rpm PTO shaft of a tractor supplying a minimum of 75 kW. The peanut vac was taken to two locations in South Georgia and used to extract peanuts from farmers’ stock warehouses in addition to the conventional equipment used for warehouse bailout. The weight of peanuts on each truck, time to fill each truck, and the farmers’ stock grade factors for the peanuts in each truck was recorded and compared by conveyance method. At the first location, the conventional equipment consisted of a skid-steer loader with an oversized bucket driven into the pile of peanuts. The peanuts were emptied into a surge bin feeding a portable conveyor belt that conveyed the peanuts into a waiting truck. At the second location, a large articulated bucket loader was used in lieu of the skid-steer loader. Peanuts loaded using the conventional method averaged 5.2% foreign material (FM) and 6.7% loose shelled kernels (LSK). Peanuts loaded using the peanut vac averaged 2.7 and 4.9% FM and LSK, respectively. Trucks were loaded at a rate of 187 MT/h using conventional equipment compared to 61MT/h using the peanut vac.