Method for pressing bagasse webs

Claim 1

The method of forming a continuous web from a slurry of bagasse fibers comprising: projecting a slice stream of bagasse slurry between a pair of looped traveling forming wires and draining water through the wires for forming a one-sided web; lifting the formed web off one of the wires and substantially immediately passing the web through a first press nip sandwiched between a first upper press felt and a second lower press felt for pressing water uniformly from the web in both directions; passing the web through a second press nip sandwiched between said second press felt and a third press felt and supporting the web from the one forming wire continuously through said first nip on the lower surface of the first felt, supporting the web on the second press felt from the first nip through the second nip; laying the web on a plain roll after the second nip, supporting the web continuously on said third felt between the second nip and plain roll; pressing the web against the plain roll in a third nip with the third nip formed between the third press felt and the plain roll; maintaining the web on the plain roll after the third nip and passing the web against the plain roll in a fourth nip with a fourth press felt being outwardly of the web; removing the web from the plain roll after the fourth nip for transfer to a dryer section; applying a pressure in the first press nip in the range of 200 to 250 pounds per linear inch; applying a pressure in the second nip in the range of from 300 to 350 pounds per linear inch; applying a pressure in the third press nip in the range of 350 to 400 pounds per linear inch; and applying a pressure in the fourth nip in excess of 500 pounds per linear inch.

Claim 2

The method of forming a continuous web from a slurry of bagasse fibers comprising: projecting a slice stream of bagasse slurry between a pair of looped traveling forming wires and draining water through the wires for forming a one-sided web; lifting the formed web off one of the wires and substantially immediately passing the web through a first press nip sandwiched between a first upper press felt and a second lower press felt for pressing water uniformly from the web in both directions; passing the web through a second press nip sandwiched between said second press felt and a third press felt and supporting the web from the one forming wire continuously through said first nip on the lower surface of the first felt, supporting the web on the second press felt from the first nip through the second nip; laying the web on a plain roll after the second nip, supporting the web continuously on said third felt between the second nip and plain roll; pressing the web against the plain roll in a third nip with the third nip formed between the third press felt and the plain roll; maintaining the web on the plain roll after the third nip and passing the web against the plain roll in a fourth nip with a fourth press felt being outwardly of the web; removing the web from the plain roll after the fourth nip for transfer to a dryer section; applying a pressure in the first press nip in the range of 200 to 250 pounds per linear inch; applying a pressure in the second nip in the range of from 300 to 350 pounds per linear inch; applying a pressure in the third press nip in the range of 350 to 400 pounds per linear inch; and applying a pressure in the fourth nip in excess of 500 pounds per linear inch.