Development of A Revolving Die and Roller Fish Feed Pelletizer

A revolving die and roller type pelletizing machine was designed and constructed to produce fish feed pellets for small scale fish farmers. The major components of the pelletizer were the hopper, rollers, a flat die, shaft, discharge tray, frame, V-belt, V-pulley and electric motor. These components were designed based on strength and rigidity. An electric motor drives the die by a shaft connected to its pulley. The rotation of the die initiates the rotation of the rollers which pick up the feed material and compress it into the die holes to form pellets. The pelletizing machine was tested at two speed levels of 507 and 761 rpm and at three moisture content (MC) levels (wet basis) of 20, 25 and 30 20At 30 0MC, highest pellet output of 34.3 kg/hr and 40.4 kg/hr were obtained for die speeds of 507 and 761 rpm respectively. Higher pellet output obtained from die speed of 761 rpm could be as a result of the production of higher heat which resulted in proper gelatinization of the carbohydrate in the compounded feed. The gelatinized starch acts as a binding agent and this reduces crumbling during pelleting. The small and medium scale fish farmer can operate the machine because of its simplicity and this will alleviate the problem of sourcing for imported fish feed.