Development and Evaluation of Cutting Knives to Suit Cutting Wet and Dry Field Residues

Abstract

The aim of the present work is developing of the performance of cutting knives in crop residues shredder. The items to achieve the aim of the present study are: (1) Study of some physical and mechanical properties of cotton stalks and rice straw. (2) Evaluation of shredder performance and cutting knives before and after development.(3) production of cutting knives from local materials. (4) Development of cutting knives. (5) Chopping machine cost. The performance of chopping machine was tested under the following parameters: A-Four cutter speeds (900, 1050, 1200 and 1500 rpm), B-Three different moisture content (30.0, 40.0 and 50.0 %) and (22.0, 25.0 and 30.0% , w.b.) for cotton stalks and rice straw, respectively. C-Two different types of shapes cutting knives {smooth-edge (Original knives) and serrated-edge (Modified knives)}. The final results of this study could be summarized as follows:-Generally by increasing the cutter head speed from 900 to 1500 rpm tends to increase percentage of cutting length > 2cm from (86.2 to 90.6%) and (83.8 to 87.0%), chopper productivity from (1.10 to 1.70 Mg/h) and (1.00 to 1.50 Mg/h), degree of destruction from (42.5 to 53.0 %) and (29.0 to 35.0%), useful power from (1.19 to 3.05 kW) and (1.10 to 2.80 kW) and unit energy from (1.88 to 1.79 kW.h/Mg) and (1.10 to 1.87 kW.h/Mg) for cotton stalks and rice straw, respectively, with machine before modification at moisture content of 30.0 % and 22.0 % (w.b.) for cotton stalks and rice straw, respectively and type of cutting knives smooth-edge (Original knives). Also, increased percentage of cutting length > 2cm from (91.7 to 94.5 %) and (85.7 to 89.5 %), chopper productivity from (1.30 to 1.80 Mg/h) and (1.20 to 1.60Mg/h), degree of destruction from (50.9 to 72.5 %) and (45.4 to 60.8%), useful power from (1.10 to 2.70 kW) and (1.00 to 2.20 kW) and unit energy from (0.85 to 1.50 kW.h/Mg) and (0.80 to 1.40 kW.h/Mg) with machine after modification at moisture content of 30.0 % and 22.0 % (w.b.) for cotton stalks and rice straw, respectively, and type of cutting knives serrated-edge (Modified knives).

Maximize the Utilization of some Residuals Food Manufacture

“…( 6). These results are in agreement with those reported by Nasr (2000) and EL-Khateeb and El-Keway (2012). By increasing the speed of knives, the machine becomes more productive because there is more cutting and pressing of the orange peel.…”

A combined machine for collecting and chopping rice straw

“…(2013) and El-Khateeb (2001) reported that increasing cutter speed from 500 to 1500 rpm increases the percentage of cutting length in the range (0.2 cm) by (54–93%). Meanwhile, El-Khateeb and El-Keway (2012) found that the maximum percentage of ‏>‏ 2 cm cutting length of 94% was recorded at 1500 rpm cutting speed for 22% (w.b.) rice straw moisture content.…”