Optimum Design of Yankee Hoods For Economic Drying, 1995 Papermakers Conference Proceedings

I.G. Lang ABB Drying The optimization of Yankee Hood design for economic drying is a process which analyzes the following factors and their contribution to overall efficiency and cost; Nozzle Geometry Fuel and Electrical Cost Heat Recovery In regards to hood design, the customer should be aware of the factors affecting heat transfer and hood performance, particularly nozzle box geometry and how it affects hood energy consumption. Minimizing operating cost of Yankee Hoods requires an analysis of fuel and electrical costs to ensure the correct combination of nozzle velocity and impingement temperature in order to maximize the use of the least costly energy source. The addition of air-to-air heat recovery improves the overall energy efficiency of the drying process as does water heating for felt showers. Many mills producing their own electricity in Co-gen plants have available a high grade source of heat which may, in some cases, be used directly in the drying process to good effect. The exhaust gas from a gas turbine as found in a co-generation plant may supply all or part of the heat required for the drying process.