CN1417406A

CN1417406A - Organic solvent recovering and lignin separating paper pulp making technology

Info

Publication number: CN1417406A
Application number: CN 01129051
Authority: CN
Inventors: 罗学刚
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-11-09
Filing date: 2001-11-09
Publication date: 2003-05-14

Abstract

The present invention belongs to the technology of making cellulose pulp with organic solvent. The present invention based on that lignin is soluble in dioxane, alcohols, esters, phenols, ketone and other organic solvent. The paper pulp making process includes mixing paper-making material with solvent and acid, ammonia, anthraquinone derivative or other catalyst; reflux soaking; mashing off, filtering to separate fiber for making paper and filtrate for producing high-purity high lignin through concentration and separation; and recovering organic solvent. The present invention prevent effluent pollution and can realize green papermaking without pollution or with only low pollution.

Description

Reclaim organic solvent method separating lignin paper pulp making technology

(1) technical field: the present invention relates to a kind of cellulose containing raw material process, particularly with the lignin in organic solvent separation, hydrolysis or the dissolving paper making raw material and utilize it to produce the method for paper pulp with organic solvent slurrying.

(2) background technology: pulp and paper industry is one of mainstay industry of China and even World Economics.China increases sharply to the demand of paper in economic liftoff.Yet well-known pulp and paper industry also is environmental pollution and major power consumer.The waste water that produces is startling to the pollution of rivers,lakes and seas.In paper industry, what generation was polluted to environment mainly is cooking waste liquor (the red liquid that black liquor that sulfate process or alkaline cooking produce and acid sulfite process produce), its pollutional load accounts for more than 80% of whole industrial pollution caused by paper manufacturing, according to statistics, world's slurrying total amount in 1985 reaches 14019.3 ten thousand tons, chemical pulping accounts for 70.64%, and China's slurrying total amount in 1989 reaches 1,330 ten thousand tons.Occupy an leading position in the soda pulping process chemical pulping at home and abroad.China's sulfate pulping (containing alkaline process) amount accounts for more than 70% of chemical pulping amount, and the slurrying amount reaches 3,000,000 tons/year, if paper pulp per ton produces the black liquor (its COD is up to 50000mg/L) of 10～12 tons of 6B ' e in theory, promptly annual product black liquor amount reaches 30,000,000 tons.Paper waste has caused China's people's lives and ecological environment and has seriously influenced, once make Basin of Huaihe River near the city water supply interrupt, the farmland underproduction, resident's disease increases.The little paper mill that over thousands of family produces 5000 tons of less thaies per year was once ordered to close by State Council in 1996, but still having fairly large paper plant constantly to produce black liquor waste pollutes, except that containing a large amount of free residual alkali, also contain many water soluble organic substances in these black liquor, as lignin etc.Lignin is with its complex structure, and the biodegradation difficulty is the main organic pollution of paper industry.

(3) summary of the invention: the purpose of slurrying is to handle various paper making raw materials with physics (as Mechanical Method), chemistry (as alkaline process, sulphite process), biochemistry methods such as (as enzyme process), removes the impurity such as lignin in the raw material, makes the frotation pulping.The present invention utilizes lignin to dissolve in dioxane, alcohols is (as methyl alcohol, ethanol), the ester class is (as Ethyl formate, ethyl acetate), phenols is (as phenol, benzenediol), ketone is (as acetone, butanone), the character of solution such as acetyl bromide, when paper-making pulping, behind paper making raw material and above-mentioned single solvent or double solvents mixing machinery defibrination, again through the dipping that refluxes, mashing off or high pressure mashing off, organic solvent penetrates in paper making raw material space between cells and the cell, separate, hydrolysis or dissolved lignin, mixed slurry is through pressing (mistake) filter, isolated fiber is sized mixing and is copied paper, filtrate goes out high Vinsol through airtight concentrating and separating and is used for deep development, the organic solvent recycling.For accelerating reaction process, can when adding organic solvent, add acids (example hydrochloric acid, acetate) or Ammonia (as ammonia, ammoniacal liquor) or amine (as methylamine, ethamine) or amino anthraquinones or sulphite (as sodium sulfite, sodium pyrosulfite) as catalyst.For the loss that reduces organic solvent in the course of reaction and to the pollution of environment, steps such as defibrination, backflow dipping, mashing off and concentrating and separating can be carried out in confined conditions.Its technical matters flow process is as follows:

Organic solvent

↓ paper making raw material → pulverizing → airtight defibrination → airtight backflow dipping → airtight mashing off or high pressure mashing off → filtration or press filtration → fiber → size mixing and copy paper

↓

This quality ← filtrate → organic solvent (circulation)

Because what the present invention adopted in whole pulping process is organic solvent separation, hydrolysis or dissolved lignin, and organic solvent is recycling use repeatedly, no waste water or a small amount of discharge of wastewater, really can prevent and treat the contaminated wastewater of pulping and paper-making to environment from the source, be the effective technical way of realizing pollution-free or low pollution " environmental protection " papermaking.

(4) specific embodiment: embodiments of the invention see the following form:

Embodiment number	Handle raw material	Organic solvent and addition					Catalytic amount (weight %)		Mashing off	Remarks
		Organic solvent and addition					Catalytic amount (weight %)		Mashing off		Dioxane	Acetyl bromide	Methyl alcohol	Ethyl acetate	Phenol	Acetone	Amino anthraquinones	Acetate	Sulphite	Normal pressure	High pressure
		??1	Eucalyptus		???1						Dioxane	Acetyl bromide	Methyl alcohol	Ethyl acetate	Phenol	Acetone	Amino anthraquinones	Acetate	Sulphite	Normal pressure	High pressure	??√	High pressure range 200 \| 1000 kPas
??2	Birch	??1	Eucalyptus		???1										??2				??√			??√
??2	Birch	??3	Chinese alpine rush	??2			???2	???0.2							??2				??√		??√
??4	Wheat straw	??3	Chinese alpine rush	??2			???2	???0.2		??3	??2					???0.3			??√		??√
??4	Wheat straw	??5	The bamboo class	??1		???2			??0.2	??3	??2					???0.3			??√			?√
??6	Yellow bluish dogbane	??5	The bamboo class	??1		???2			??0.2					???2				???0.1	??√			?√
??6	Yellow bluish dogbane	??7	Bagasse		???2				??0.2					???2				???0.1	??√		??√

Annotate: organic solvent and addition are meant the organic solvent umber with the correspondence adding of a paper making raw material institute in the table.

Using method of the present invention is: the paper making raw material (needle after will pulverizing, the broad-leaved wood class, the bamboo class, Chinese alpine rush, careless class such as sisal hemp, wheat straw, agricultural crop straw classes such as cornstalk, cotton stalk bark, bast classes such as mulberry skin, flax, yellow bluish dogbane, linen-cotton classes such as cotton, Deng) press raw material: organic solvent=1: 1～5 (weight ratio, down with) the catalyst of ratio and 0～5% (weight of solvent than) in confined conditions behind the mixing machinery defibrination, again through airtight backflow dipping, airtight mashing off or airtight high pressure (200～1000 kPas) mashing off, mixed slurry is through pressing (mistake) filter, the papermaking of sizing mixing of isolated fiber, filtrate goes out high Vinsol through airtight concentrating and separating and is used for deep development, the organic solvent recycling.Organic solvent wherein is arbitrary concentration and be good with high concentration; Catalyst is for adding acids or Ammonia or amine or amino anthraquinones or sulphite.

Embodiments of the invention all can be implemented.The invention is not restricted to the foregoing description, to those skilled in the art, it is conspicuous not leaving various corrections and the variation that the spirit and scope of the present invention make.

Claims

1, a kind of recovery organic solvent method separating lignin paper pulp making technology in turn includes the following steps, and the papermaking of sizing mixing of raw material pulverizing → defibrination → mashing off → filtration → fiber is characterized in that, adds organic solvent when defibrination; Filtrate filtered goes out organic solvent and lignin through concentrating and separating.

2, recovery organic solvent method separating lignin paper pulp making technology according to claim 1 is characterized in that, can add acids, ammonia or amine, amino anthraquinones or sulphite as catalyst when adding organic solvent.

3, recovery organic solvent method separating lignin paper pulp making technology according to claim 1, it is characterized in that described organic solvent is the mixture of dioxane, alcohols, ester class, phenols, ketone, acetyl bromide or dioxane and hexafluoro propyl alcohol or acetyl bromide or ethanol.

4, according to claim 1,2, one of 3 described recovery organic solvent method separating lignin paper pulp making technologies, it is characterized in that steps such as described defibrination, backflow dipping, mashing off and concentrating and separating are carried out in confined conditions.