CN1103685A

CN1103685A - High-concentration de-inking method for waste paper

Info

Publication number: CN1103685A
Application number: CN 93120620
Authority: CN
Inventors: 王竹友; 李运来
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-12-07
Filing date: 1993-12-07
Publication date: 1995-06-14

Abstract

The de-inking process includes following three steps: (1) Loading water of 25-70 deg.C and de-inking agent in the amount of 3-5.5 wt% of waste paper into rotary metallic container of 10-80 cubic meter in volume with the weight ratio of the total amount of water and de-inking agent to the waste paper being 2.3-4 to 1; (2) Loading aired waste paper into the container in the amount of 155-200 kg for each cubic meter of effective volume and rotating the container at the speed of 2 rpm for 1.0-2.5 hr; and (3) Discharging and washing de-inked paper pulp. The said process is simple and has low power consumption, high efficiency and low cost.

Description

High-concentration de-inking method for waste paper

The invention belongs to papermaking, particularly the job lot paper de-inking method.

Deinking reproduces paper pulp or paper can repeatedly be recycled the papermaking resource, replenishes insufficient raw material, and significantly energy-conservation, reduces environmental pollution, reduces product cost.The utilization again of existing waste paper must be passed through deinking process, its de-inking method has: floatation, washing method, high dense deinking pulping process, floatation is that job lot paper is sent into hydrabrusher, size degradation form slurry under 5-7% concentration, under the temperature that is no more than 45 degree, parked therein 30 minutes, sending into medial launder then soaked 1-2 hour, again after a high dense pulp screen sieve removes lumps, the concentration of slurry is transferred to 0.8%, add deinking agent and in flotation device, remove removal ink, impurity such as pigment, transfer dense standby then to 4%-6%, washing method also is at hydrabrusher size degradation pulping with waste paper, put into dispersant in the time of size degradation in hydrabrusher, distributes ink becomes tiny colloidal particle, removes impurity such as removal ink again through washing.High useless degree paper deinking pulping process is that deinking concentration is brought up to 14% from 5-7%, and employing equipment is 2.5M ³High density hydraulic pulper and Φ 1000mm flotation device etc., its master operation have hydraulic pulping-insulation-stop-slagging-off-screening-floatation and ink removing-concentrated-bleaching.Above-mentioned several method all adopts hydrabrusher, its structure is similar to washing machine structure, container inner bottom part (vertical) or sidepiece (horizontal) are equipped with per minute and reach the impeller that hundreds of changes, during work, impeller is stirred water and paper stock, and repulping of waste paper or size degradation and deinking are carried out simultaneously, because slurry is high to the impeller resistance of motion, installed capacity and power consumption are very big, if 2.5 ³Hydrabrusher day production capacity 15-20 ton, installed capacity is up to 55KW, ton deinking slurry power consumption reaches 20.4 degree, in a word, above-mentioned several method installed capacity is big, and deinking concentration is low, power consumption and chemicals consume high, and need ad hoc bleaching process could guarantee the whiteness of starching, it is low to have method deinking concentration now, between paper pulp fiber a little less than the rubbing action, deinking efficient is difficult to improve, if force to improve deinking concentration, not only slurry is difficult to discharge from the hydrabrusher sieve aperture, prolongs the discharge time, and power consumption rises suddenly, concentration as slurry brings up to 16.1% from 14.4%, only increases by 1.6 percentage points, and ton slurry power consumption is promptly increased sharply to 30 degree by 20.4 degree, improve 47%, the repulping of waste paper time also extended to 26 minutes from 16 minutes, and the time increases by 62%, and visible current technology method is the Danone power limit.In addition, current methods has strengthened the input ratio of deinking agent for guaranteeing the deinking quality, and general input amount reaches the 7-10% of air-dry waste paper amount, and this must strengthen production cost.

The object of the invention provides a kind of new de-inking method, and this method energy consumption is little, the efficient height, and cost is low.

For achieving the above object, the present invention by the following technical solutions: (1) is 25 ℃-70 ℃ water at low temperature with temperature and is 10M with respect to the deinking agent of the waste paper weight 3%-5.5% volume of packing into ³-80M ³Sphere or cylinder and angle tangible in the container that the rotating metallic plate of body is made, the total amount of water and deinking agent and the about 4-2.3 of waste paper weight ratio: 1; (2) the air-dry waste paper of in container, packing into, charge weight is every cubic metre of dischargeable capacity charging 155-200kg, and closes the material mouth, and container is no more than two circular velocities with per minute and rotates under power drive, time 1.0-2.5 hour, the paper stock size degradation became paste printing ink also to separate with paper pulp fiber; (3) open discharging opening, deinking slurry is poured in the pond washed with water, make printing ink discharge soluble in water.

Above-mentioned deinking agent can be used the deinking agent that generally adopts, for example, the formula rate of recommending in " application of non-ionic surface active agent " book by Weng Chenghua, Zhang Wanfu translation etc., the consumption of deinking agent is controlled at 3-5.5%, if adopt useless utmost point paper, consumption is low with respect to useless books, and temperature control is that disregard message paper is higher relatively.Deinking agent consumption of the present invention is controlled at:

Fatty alcohol-polyoxyethylene ether 0.4-0.8%

Sodium carbonate 1.3-1.9%

Carboxymethyl cellulose 0.08-0.12%

Sodium metasilicate 0.8-1.2%

Hydrogen peroxidase 10 .8-1.2%

Advantage of the present invention: this method adopts container to make the repulping of waste paper deinking from the mode that body rotates, resistance and the rigid impact of having avoided the hydrabrusher impeller to rotate at a high speed, deinking is moved under a kind of state of softly releiving, deinking concentration significantly rises, power consumption descends significantly, the drubber of a day output 15-20 ton waste paper for example, ton slurry power consumption 2-3 degree, equipment installed capacity 3.3-4.4KW, these two indexs are 10% of hydrabrusher, and deinking concentration is existing method 1.5-4 times up to 20-30%, high concentration has increased the rubbing action between paper pulp fiber greatly, efficient obviously improves, and reduces 2/5-3/5 with the China ink amount than current methods, and the deinking water consumption reduces relatively, paper pulp after the deinking needn't pass through ad hoc bleaching process, and whiteness can reach copies the paper requirement.

Below in conjunction with embodiment the present invention is elaborated:

Embodiment 1:

Water is heated to 60 ℃, inject 14M ³Rotary spherical digester in, then by the prescription deinking agent is dissolved in the rotary spherical digester water, the prescription of deinking agent is: fatty alcohol-polyoxyethylene ether 0.4%, carboxymethyl cellulose 0.1%, hydrogen peroxide 1%, sodium carbonate 1.3%, sodium metasilicate 1%, (injected water volume and deinking dosage amount to 8 tons in the rotary spherical digester), again 2 tons of air-dry disregard message paper are packed in the ball, make waste paper concentration reach 20%, then sealing material mouth, container is slowly rotated with the speed in one week of per minute, and deinking and paper stock crushing process begin at once.

After 2 hours effective deinking time, paper stock size degradation pulping, printing ink also separates with paper pulp fiber, opens rotary spherical digester material mouth this moment, the deinking slurry is poured in the ball lower storage reservoir washed, and under the washings effect, the printing ink that will be dissolved in the deinking slurry is cleaned discharge.

Above-mentioned deinking is starched to join and is copied the bleached chemical long fiber pulp, and can manufacture paper with pulp becomes to be up to state standards (GB-1910-89) A level or B level, is suitable for the offset printing newsprint that uses for the high speed rotary offset machine.

Embodiment 2:

Water heated after 60 ℃, inject 25M ³In the rotary spherical digester, by prescription deinking agent is dissolved in the rotary spherical digester water then, the prescription of deinking agent is: fatty alcohol-polyoxyethylene ether 0.4%, carboxymethyl cellulose 0.1%, hydrogen peroxide 1%, sodium carbonate 1.3%, injected water volume and deinking dosage amount to 10.5 tons in the sodium metasilicate 1%(rotary spherical digester), in the ball of again 4.5 tons of air-dry disregard message paper being packed into, make waste paper concentration reach 30%, sealing material mouth makes container slowly rotate with the speed in one week of per minute then, and deinking and paper stock crushing process begin at once.

Embodiment 2 improves deinking efficient 50% than embodiment 1, and ton deinking slurry power consumption is 1.96KW, reduces power consumption 40% than example 1; Reduce power consumption 90% than traditional approach, water saving 40%, efficient is 4.3 times of traditional approach.

Claims

1, a kind of de-inking method is characterized in that it may further comprise the steps:

(1) is 25 ℃-70 ℃ water at low temperature with temperature and is 10M with respect to the deinking agent of the waste paper weight 3%-5.5% volume of packing into ³-80M ³Sphere or cylinder and polygonal in the container that the rotating metallic plate of body is made, the total amount of water and deinking agent and the about 4-2.3 of waste paper weight ratio: 1;

(2) the air-dry waste paper of in container, packing into, charge weight is every cubic metre of dischargeable capacity charging 155-200kg, and closes the material mouth, and container is no more than two circular velocities with per minute and rotates under power drive, time 1.0-2.5 hour, the paper stock size degradation became paste printing ink also to separate with paper pulp fiber;

(3) open discharging opening, deinking slurry is poured in the pond washed with water, make printing ink discharge soluble in water.

2, by the described de-inking method of claim 1, it is characterized in that described deinking agent is:

Fatty alcohol-polyoxyethylene ether 0.4-0.8%

Carbon sodium sulphate 1.3-1.9%

Carboxymethyl cellulose 0.08-0.12%

Sodium metasilicate 0.8-1.2%

Hydrogen peroxidase 10 .8-1.2%