Manufacture of non-woven fibrous material from a foamed furnish

Claim 2

A PROCESS FOR MANUFACTURING A NON-WOVEN FIBROUS MATERIAL FROM A FOAMED FIBER DISPERSION FED TO A FORAMINOUS SUPPORT FROM A FOAMING DEVICE WHEREIN THE AMOUNT OF SURFACE ACTIVE AGENT REQUIRED IS REDUCED, THE PROCESS COMPRISING: ESTABLISHING AN AIR/WATER/FIBERS/SURFACE ACTIVE AGENT MIXTURE PROVIDED BY A MIXER; DELIVERING SAID MIXTURE TO A CLOSED FOAMING DEVICE AND EFFECTING FOAMING THEREOF BY THE CREATION OF TURBULENCE WITHOUT THE USE OF MOVING MECHANICAL MEANS TO ESTABLISH SAID FOAMED FIBER DISPERSION; FEEDING SAID FOAMED FIBER DISPERSION TO SAID FORAMINOUS SUPPORT; RECOVERING, BY VACUUM DRAINING THROUGH VACUUM BOX MEANS, A MAJOR PART OF THE LIQUID, GENERALLY IN A FOAMED CONDITION, FROM SAID FOAMED FIBER DISPERSION ON SAID FORAMINOUS SUPPORT; RECIRCULATING SAID LIQUID SO RECOVERED GENERALLY IN A FOAMED CONDITION DIRECTLY FROM SAID VACUUM BOX MEANS TO SAID MIXER;

Claim 3

The method according to claim 1 including the step of dispersing clumps of fibers following introduction of metered quantities of air and surface active agent and prior to passage to the mixer.

Claim 4

A closed circuit system for manufacturing non-woven fibrous material from a foamed fiber dispersion wherein the amount of surface active agent required is reduced, the system comprising: a mixer for establishing an air/water/fibers/surface active agent mixture; a closed foaming device, downstream of said mixer, for effecting foaming of said mixture by the creation of turbulence without the use of moving mechanical means; pipe means for deliverying said mixture from said mixer to said closed foaming device; feeding means for feeding said foamed fiber dispersion effected by said closed foaming device to a foraminous support on which said non-woven fibrous material is formed; vacuum drain means, including vacuum box means, for recovering a major part of the liquid, generally in a foamed condition, from said foamed fiber dispersion on said foraminous sUpport; a pulper connected by pulp delivery pipe means to said mixer; pump means operable to recycle said liquid so recovered generally in a foamed condition directly from said vacuum box means through said pulp delivery pipe means to said mixer; and metering means operable to introduce into said pulp delivery pipe means upstream of said mixer metered quantities of air and make-up surface active agent.

Claim 5

A closed circuit system for manufacturing non-woven fibrous material from a foamed fiber dispersion wherein the amount of surface active agent required is reduced, the system comprising: a mixer for establishing an air/water/fibers/surface active agent mixture; a closed foaming device, downstream of said mixer, for effecting foaming of said mixture by the creation of turbulence without the use of moving mechanical means; pipe means for deliverying said mixture from said mixer to said closed foaming device; feeding means for feeding said foamed fiber dispersion effected by said closed foaming device to a foraminous support on which said non-woven fibrous material is formed; vacuum drain means, including vacuum box means, for recovering a major part of the liquid, generally in a foamed condition, from said foamed fiber dispersion on said foraminous sUpport; a pulper connected by pulp delivery pipe means to said mixer; pump means operable to recycle said liquid so recovered generally in a foamed condition directly from said vacuum box means through said pulp delivery pipe means to said mixer; and metering means operable to introduce into said pulp delivery pipe means upstream of said mixer metered quantities of air and make-up surface active agent.

Claim 6

The system according to claim 3 including a deflaker in said pulp delivery pipe means, downstream of said metering means and upstream of said mixer, for effecting dispersion of fiber clumps passing through said pulp delivery pipe means.