The Lundberg Liquor Filter is designed for filtering spent cooking liquor or filtrates in the
chemical pulping industry. Filtering of liquors removes the re-usable fibers and prevents
their introduction into evaporators, heat exchangers or other fiber intolerant equipment.
Liquor pumped into the inlet vat overflows into the drum trough and filters through to the
interior of the drum. The filtered liquor is discharged from the inside of the drum, and the
separated fibers and other solids are carried on the outside of the drum over the outlet
weir into the reject outlet. The drum submerges on the inlet side. The fiber is removed
from the drum by flushing with filtered liquor. The principle of operation is shown on
Lundberg Drawing No. SC-1011-C.
Normally a wire of 60 mesh is used for black liquor service to retain the fibers and to let
the fine fraction and other solids pass through with the filtered liquor. An 80 or 100 mesh
wire can be used. However, on 100 mesh a large amount of "other solids" may also be
removed and these solids may tend to blind the filter cloth.
The entire filter is constructed of stainless steel, either type 304 or 316, to customer
specification. The filter drum is 42 inches in diameter with a minimum width of 36 inches.
As capacity requirements increase, the drum width is increased in 18-inch increments.
The drum consists of a stainless steel pipe shaft upon which the filter wire support system
is constructed. Except for the solid drive end, spiders are used to support the ring bearing
bars. Upon these bars, at one-inch intervals, are the wire support rings. The filter wire
is installed over the wire support rings and held in place at the seam, which is covered
by the fiber carrier. The ends of the wire are sealed in place with stainless steel bands.
The drum trough, inlet box and reject outlets are supplied as a unit. A removable vapor
hood, with suitable inspection doors, is provided to safeguard against steam and fumes
escaping in the operating area. A connection is provided to the hood for an atmospheric
vent or fume blower provided as an option or by the customer.
The drum is driven at 5 RPM with a 5 HP motor through a gearbox.
Lundberg Liquor Filter Outline Dimesions