Patent ID: 8734615
Filing Date: 2014-05-27
Classification: D21F,D21H,F26B

Abstract:
1. A method of treating a continuous paper web, the method comprising the steps of: applying metered quantities of a urea resin dissolved in water to the paper web; passing the paper web in a travel direction through a succession of drying zones of a dryer; recirculating at least a portion of the air in each of the dryer zones by passing a portion of the air in each zone through a respective heater and a respective blower and blowing the hot air produced in the heater as recirculating air from the respective blower against the web from a respective nozzle system; monitoring a temperature in each of the drying zones; modifying the temperature of the paper web in each of the drying zones by controlling a quantity or a temperature of the recirculating air via the respective blowers and/or heaters for each of the drying zones so that the temperature of the paper web reaches a maximum of 99° C.; and extracting exhaust air exclusively from a furthest upstream one of drying zones and supplying fresh air exclusively to a furthest downstream one of the drying zones as part of the recirculating air such that the air in the zones moves upstream from zone to zone.