High-intensity drying processes - impulse drying
Experiments have been conducted on a sheet-fed pilot-scale shoe press to compare impulse drying and double-felted pressing. Both an IPST ceramic coated and Beloit Type A press roll have been evaluated for linerboard sheet structures having a wide range of z-direction permeability. Both roll surfaces evaluated had thermal properties that are covered by IPST impulse drying patents. The intent of the experiments was to find ways of correcting sheet sticking problems observed in previous pilot-scale shoe press experiments; to compare the performance of the IPST ceramic press roll surface coating to Beloit`s Type A surface; to conduct the experiments over a wide range of linerboard sheet structures; and to evaluate the resulting linerboard in terms of key physical properties. Previously observed sheet sticking problems had been partly traced to excessive press roll surface roughness. Hence, both roll surfaces used in the current experiments were diamond ground to achieve improved surface smoothness. Previous work had also raised the possibility that sheet sticking could also be contributed to by the deposit of calcium carbonate from the felt wash water to the heated press roll surface. To test this later hypothesis, the Beloit Type A press roll was evaluated using soft (deionized) and hard (calcium carbonate containing) felt wash water. It was observed that as long as the press roll surface temperature exceeded 150{degrees}C, sheets would not stick to the press roll surface. An attempt was made to evaluate the IPST ceramic coated press roll in a similar way, however roll surface failure prevented experiments from being conducted with hard felt wash water. When soft felt wash water was used, the IPST ceramic coated press roll only showed signs of sticking at press roll temperatures below 150{degrees}C.
- Research Organization:
- Institute of Paper Science and Technology, Inc., Atlanta, GA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG02-85CE40738
- OSTI ID:
- 10184568
- Report Number(s):
- DOE/CE/40738-8; ON: DE94019110; TRN: 94:008574
- Resource Relation:
- Other Information: PBD: Dec 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
A comparison of impulse drying to double felted pressing on pilot- scale shoe presses and roll presses
A comparison of impulse drying to double felted pressing on pilot- scale shoe presses and roll presses. Progress report, No. 6