Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Continuous chemical treatment or continuous charging or...
Patent
1981-10-30
1986-07-08
Alvo, Steve
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Continuous chemical treatment or continuous charging or...
162 25, 162 26, 162 28, 162 65, 162 78, 162 84, 162 86, D21C 104, D21C 326
Patent
active
045991383
ABSTRACT:
A process is provided for pretreating particulate lignocellulosic material to remove heavy metals and resin without any delignification or defibration, which comprises washing particulate lignocellulosic material; compressing the washed material to a solids content of at least 40% to remove absorbed and excess liquid; impregnating the compressed material with an alkaline aqueous solution comprising alkali and at least one of a heavy metal ion complexing agent and a heavy metal ion reducing agent; heating the impregnated material at a temperature within the range from abut 50.degree. to 100.degree. C. for up to approximately 0.75 hour; compressing the pretreated material to a solids content of at least 40%; and separating undiluted liquor squeezed out during the compression, while maintaining conditions during the pretreating such that the pH of the squeezed-out liquor is within the range from about 4 to about 9.5; thereby separating heavy metal ions, resins and alkali-extracted substances in solution in the expressed liquor, but not any lignin.
REFERENCES:
patent: 2717195 (1955-09-01), Armstrong
patent: 3023140 (1942-02-01), Textor
patent: 3467574 (1969-09-01), West
patent: 3578554 (1971-05-01), Richter
patent: 3811993 (1974-05-01), Ghisoni
patent: 4029543 (1977-06-01), Lindahl
patent: 4050981 (1977-09-01), Jamicson et al.
patent: 4052280 (1977-08-01), Mackie
patent: 4152197 (1979-05-01), Lindahl et al.
patent: 4187141 (1980-02-01), Ahrel
Continuous Pulping Processes; Rydholm; TAPPI, Publication Stap No. 7, 1970.
Kamyr, Pulp Equipment, Kamyr AB, Feb. 1972.
Refiner Mechanical Pulping, Defibrator AB.
Alvo Steve
Mooch Domsjo Aktiebolag
LandOfFree
Process for pretreating particulate lignocellulosic material to does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for pretreating particulate lignocellulosic material to , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for pretreating particulate lignocellulosic material to will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1449785