Design, Construction And Performance Evaluation Of A Magnetic Sieve Grinding Machine
ABSTRACT
Technology of milling and grinding machine is one of the simplest methods of processing agricultural raw materials alternative to the traditional methods of grain/tuber processing using stone, mortar and pestle. However, machines constructed using metal plates results in tearing and wearing away of the materials of construction. The effect of this is the contamination of the processed foodstuff. This is known to have negative health implications when accumulated and consumed in large quantities. In this study a magnetic sieve grinding machine was designed, constructed and the performance evaluation undertaken in order to remove the toxic metal filing contaminants that cause the health hazard in food when consumed. The machine consists of a 0.04m3 capacity hopper, a machine housing, a blower with 13.35m/s air speed, a cyclone, set of hammers that effect the size reduction of the materials been fed, 12cm width rotor pulley, a shaft of 50cm in length and a magnetic sieve that separate metal filings from the grounded food stuff. The machine is powered by a 5.96 kW diesel engine. Performance evaluation showerd that 10.5g of the machine parts were worn out after 10hours of grinding. The throughput capacity and the efficiency of the machine are 600kg/hr and 87.5% respectively. Thus, from the results of the investigation, the objectives of the study were achieved. The use of the magnetic sieve grinding machine by local food processors will help reduce the rate of food contaminations during post harvest processing of biomaterials and also safeguard people’s health through food security.