Purpose
The patented GL&V Air Evacuation Nozzle (AEN) is designed to prevent air
back-flow through the digester neck during the chip fill operation. Gravity
chip filling is commonly used in conventional batch digester plants, and air
blow-back is a major problem during the chip filling operation. As the chips
enter the digester, air inside is compressed and escapes through the digester
neck through which the incoming chips are flowing. This air back-flow occupies
65% of the total digester port area, leaving only 35% of the area available for
chip fill flow. Steam and odorous gases from the cooking liquor fill that is
happening at the same time as the chip fill also flow back through the digester
neck. This creates TRS emission problems in the digester area. The AEN is a
bolt-on unit that is placed between digester neck and the capping valve. The
bottom perforated section is inserted in the digester neck and draws out air,
steam and TRS which can then be directed to either the NCG system or the chip
bin.
Benefits
· Reduce chip fill time up to 40% (with Chip Bin arrangements)
· Eliminates dust and TRS from the capping floor area
· More uniform chip distribution in the digester
· Provides easier liquor fill and leaves less air between chips