الفهرس | Only 14 pages are availabe for public view |
Abstract This investigation was about mechanism used in forming of grain chaff by pressing and bonding into pellets. A screw-manual pelletizer was used with wheat dust conditioned with water. Pelleting pressure determining device and four dies were constructed. Pelleting with no heating made incoherent pellets. Pellets durability was measured by determining the percent weight of the undamaged pellets after being dropped ( 10) times of 2m height on a hard surface. Bulk density of the air-dried pellets rated (391-460) kg/m3. Pelleting pressure was limited with maximum of 4.1 bar. The addition of lignosulfonate, molasses, glue binders into dust-water mixture improved the pellets durability. Pellet lengths were (2- 4) em for fat added mixture ,and (5- 11) em for mixtures containing other binding agents. Increasing pelleting temperature 110°C increased the durability index decreased the specific energy from kW.h/ton. from 65 to by 11% and 8.08 to 4.44 Increasing die hole from 4 to 8 mm reduced specific energy by 42 %, pelleting pressure by 35% and bulk density by 15%. Cost analysis of this prototype pelletizer operation showed 0.48 L. E. per kg dust pelleting cost. Extension of the pelletizer through dimensional analysis showed 2.51% L.E. per kg dust pelletization cost by using 0. 5 ton/h capacity pelletizer driven by 13 kW engine with steamed dust mixed with 5% vinas from ”Sugar Cane Co.”. |