Turkish Journal of Agricultural Engineering Research

This study presents the possibility of using agricultural by-products to solve the problem of high forage prices. Rice mill pre-cleaning residues are considered solid waste in Egypt, as many tonnes are produced every day. These overgrown heaps always cause an environmental problem. Most millers don't know how to dispose of it. A simple device for the purification of it to use as a supplementary feeder for small birds has been manufactured. It comprises an air supply, a hopper, a case, and two drawers (one for receiving eaten parts and the other for receiving impurities). The mixture of rice millers' residues is agitated by the air stream and floats the fine particles upwardly in the far drawer while the air escapes through the final air holes. Performance evaluation was conducted on the manufactured device with various airspeeds (1.8, 2.6, 3.2 and 4.3 m s-¹), baffle angles (30, 40, and 50°) and feed rates (3.6, 5.7, 8.2, and 9.3 kg min-¹). The maximum value of purifying efficiency (87.67%) is achieved at an airspeed of 4.3 m s-1, a baffle angle of 30°, and a feed rate of 3.6 kg min-1. The minimum mean of losses (0.4%) is achieved at an airspeed of 1.8 m s-1, a baffle angle of 50°, and a feed rate of 3.6 kg min-¹. There is a significant increase in the purifying efficiency and a significant decrease in losses when using the purifying device, so it is recommended to use it for the purification of rice residues.