Shearing Characteristics of Corn Stalk Pith for Separation

Abstract

The rind of corn stalk (Zea mays L.) contains a high content of lignin, which is difficult for ruminants to digest. So, the separation of the pith and rind is the basis for the effective use of corn stalk. The shearing characteristics of pith are important parameters in the process of the separation of rind and pith for corn stalk. In this study, both the shearing strength and shearing energy were determined for the pith of cornstalk. The shearing force was measured at three moisture content levels (10 w.b.%, 40 w.b.%, and 70 w.b.%), different sample heights (lower, middle, and upper), and three different shearing speed levels (2 mm·min-1, 20 mm·min-1, and 50 mm·min-1). The shearing strength and the shearing energy were calculated from this data. The shearing energy was calculated by using the area under the shearing force versus the displacement curve. The results showed that the maximum shearing strength and the shearing energy increased as the moisture content increased. The maximum shearing strength and shearing energy were found to be 0.8452 MPa and 0.6446 J, respectively. Both the shearing strength and the shearing energy were found to be higher in the lower region of the stalk due to structural heterogeneity.

Keywords

• Corn stalk; Shearing strength; Shearing energy; Pith rind separation