Fd.E. 425 Food Engineering Design Coordinator
Middle East Technical University
Food Engineering Department
Ankara
06531
November 25, 2011
Dear Mr. Ungan,
Please accept the accompanying Work Term Report, aimed designing a toasting oven in order to produce corn flakes. In the designed system 10 tons corn flakes per day is produced. After some processes, corn flakes enters the roasting oven at 20% humidity and exits at 4%humidity.The roasting oven can operate at (±10 ºC) 225 0C.Toasting oven is designed by considering its length, area and operating temperature. Optimizations are done according to these factors on the cost of the total design. In the design system, rotary drum drier is used.350 days of the year plant works and production occurs 16 hours in a day. Corn flakes enter the oven at 225 0C .Amount of air is calculated as 0,648 kg dry air/s .Length of the drier is calculated as 2.27 m. in the result of optimizations done according to proper drying time and dryer diameter. Heat energy needed to raise the inlet temperature of air to 225 0C, is found as 157kw and heat loss is found as 23.6kw.Through these data, total investment which contains dryer cost and electricity cost is found as 92794.98TL.
Sincerely, group 3 members
TABLE OF CONTENT
SUMMARY
In this design a rotary dryer is designed for drying of corn flakes which have the moisture content 20%.Corn flakes are dried with air 9 % moisture content. The production is done for 16 hours in a day and 10 tons corn flakes are produced per day. In production process, corn flakes are cooked under pressure. After cooking step, big masses are broken to pieces and sent to driers in order to get the moisture level at 20%.After this process, product is flaked between large steel cylinders and cooled with internal water flow. Soft flakes are sent to rotary dryers in order to dehydration to 4% final moisture content and toasting. In the toasting oven, flakes are exposed to 225 0C
References: Product flow rate = (10000kg/day)*(1day/16hours)*(1 hour/3600) Product flow rate=0,174 kg/s Eqn5.(Material and Energy Balances in Food Engineering, Esin, A. 1993, p.429) Hout = 1,1742*Tout