Submitted to: Peanut Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/20/1998
Publication Date: N/A
Citation: Interpretive Summary: Peanuts are harvested with varying types of unwanted foreign material such as plant stems, rocks, dirt, and other vegetative materials. Various mechanical procedures including mechanical screening are used during post harvest processing for FM removal. Mechanical screening separates peanut materials based on diameter. A triple deck, parallel belt screen has been developed which separates materials into four diameters with one pass over of materials. Machine operational parameters including peanut material feed rate, speeds of the belts forming the decks, and belt spacing were examined to determine the performance of the new screen in making desired separations of peanut material. Peanut material feed rate onto the screen and belt speed had limited effects on separations made by the screen. Feed rate had more effect on stick separation than belt speed. The openings between the belts appeared to influence material separation more than feed rate and belt speed. Development of the triple deck, parallel belt screen offers an alternative for peanut screening providing which provides four diameters of materials.
Technical Abstract: Belt screens currently used in the peanut industry separate farmer stock peanut materials into two size categories based on diameter. Utilizing belt screens for obtaining more than two size categories requires two or more screens with different spacings between belts for each screen. A modification of the belt screen design was developed incorporating 3 screen decks into a single machine. The three decks provide the ability to separate small foreign materials, large vegetative foreign materials, and loose shelled kernels and small pods from farmer stock peanuts. The machine was equipped with spacings appropriate for screening farmer stock peanuts (cv. Florunner) for performance testing. Round belts (1.27 cm dia.) for the three decks were spaced on sheaves to provide 0.635 cm, 1.032 cm and 2.54 cm openings between belts. Screen capacity and separation performance were evaluated by varying operation parameters. The parameters evaluated were belt speeds of 105.2, 117.3, 130.0, 140.7, and 152.4 cm/s and feed rates varying from 5.17 to 27.21 Mg/hr. Within the ranges tested, feed rate and belt speed had limited effects on separations made. Feed rate had more effect on stick separation than belt speed. The openings between the belts appeared to influence material separation more than feed rate and belt speed.