CN105178082A - Method for preparing bamboo willow unbleached pulp - Google Patents

Abstract

The invention discloses a method for preparing bamboo willow unbleached pulp. The method comprises the following steps: (1) cutting bamboo willows which are two or three years old into material segments which are 40-50mm in length and 3-4mm in diameter with a rotary cutter; (2) feeding the material segments into a digester, adding 1.5%-2% of potassium hydroxide, 1.2%-1.5% of ammonium sulfite and 1%-1.5% of sodium tripolyphosphate on the basis of the oven dry weight of the material segments, and cooking the materials at 135-140 DEG C for 115-120 minutes; and (3) feeding the cooked materials into a twin-screw kneader, carrying out kneading and separating to obtain coarse pulp, and washing the coarse pulp to obtain the bamboo willow unbleached pulp. Compared with a traditional pulping method, according to the method disclosed by the invention, the pulping yield can reach 91%-93%; the length-width ratio of the fiber reaches 49.2; the BOD/COD ratio of sewage reaches about 0.5; biochemical treatment is very easy; and the pulping cost can be reduced by about 1/3.

Description

A kind of method preparing bamboo willow natural color pulp

Technical field

The present invention relates to a kind of method preparing bamboo willow natural color pulp.

Background technology

Bamboo willow is new hybridization of willows kind, and because its fast grow is good, high dense planting, strong adaptability, material is excellent, so the whole nation has large area to introduce a fine variety from south to the north.The problem of outlet pendulum of bamboo willow, in face of grower, could not only be planted and could not form commodity from introducing a fine variety existing 8 years so far, along with the increase of cultivated area! And the integrated fiber cellulose content of bamboo willow is up to 89.8%, papermaking pulping ultrahigh in efficiency, and suffer from traditional pulping process investment too large, not that general enterprises can bear; And adopt the bad solution of existing pulping process water treatment.

Summary of the invention

The technical problem to be solved in the present invention overcomes existing defect, provides a kind of method preparing bamboo willow natural color pulp.

In order to solve the problems of the technologies described above, the invention provides following technical scheme:

Prepare a method for bamboo willow natural color pulp, comprise the steps:

(1) with peeler 2 to three years raw bamboo willows are cut grow into 40-50mm, material section that diameter is 3-4mm;

(2) section material is sent into boiling vessel, by section material OD wt. basis, add the sodium phosphate trimer of the potassium hydroxide of 1.5-2%, the ammonium sulfite of 1.2-1.5% and 1-1.5%, at temperature is 135-140 DEG C, boiling 115-120min;

(3) material that boiling obtains is sent into double-screw pulp-milling and is carried out stranding mill sub-wire, and slightly starched, thick slurry obtains bamboo willow natural color pulp through washing.

Further, during step (2) boiling, solid-liquid ratio is 1:3.5.

Compared with traditional pulping process, method tool of the present invention has the following advantages:

1, pulping yield is high, can be increased to 91-93% by traditional 70-75%.

2, fiber quality is good, and average fiber length is 1.26 μm, and length and width ratio can be increased to 49.2 by traditional about 40.

3, contain a large amount of nitrogen, phosphorus, potassium in paper mill sludge, be the excellent raw material of fertilizer after biological treatment.

4, the BOD/COD ratio of sewage is high, can be increased to about 0.5 by traditional about 0.3, and very easily biochemical, water treatment can adopt the way of biological treatment, for paper-making zero discharge specifies direction.

5, slurrying cost is low, and escapable cost about 1/3 compared by simultaneous interpretation controlling slurry.

Detailed description of the invention

Below the preferred embodiments of the present invention are described, should be appreciated that preferred embodiment described herein is only for instruction and explanation of the present invention, is not intended to limit the present invention.

embodiment 1

1, by 2 to three years raw whole plant bamboo willows (containing twig, bark), the material section of long 40-50mm, diameter 3-4mm is cut into peeler, for subsequent use after removing impurity and fines with drum sieve.

2, the material section cut delivers to even steam device with belt conveyor after metering, carry out continuously cooking, the weighing scale of over dry section material is pressed in digestion process, add the potassium hydroxide of 1.5-2%, the ammonium sulfite of 1.2-1.5% and 1-1.5% sodium phosphate trimer, boiling solid-liquid ratio is 1:3.5, boiling temperature is 135-140 DEG C, and digestion time is 115-120min.

3, well-done raw material is delivered to spiral dewater in the mode of discharging, the material after dehydration enters double-screw pulp-milling and carries out stranding mill sub-wire, obtained thick slurry.

4, thick slurry obtains bamboo willow natural color pulp through 4 press masters against formula washing.

Last it is noted that the foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, although with reference to previous embodiment to invention has been detailed description, for a person skilled in the art, it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein portion of techniques feature.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (2)

1. prepare a method for bamboo willow natural color pulp, comprise the steps:

(1) with peeler 2 to three years raw bamboo willows are cut grow into 40-50mm, material section that diameter is 3-4mm;

(2) section material is sent into boiling vessel, by section material OD wt. basis, add the sodium phosphate trimer of the potassium hydroxide of 1.5-2%, the ammonium sulfite of 1.2-1.5% and 1-1.5%, at temperature is 135-140 DEG C, boiling 115-120min;

(3) material that boiling obtains is sent into double-screw pulp-milling and is carried out stranding mill sub-wire, and slightly starched, thick slurry obtains bamboo willow natural color pulp through washing.

2. method according to claim 1, is characterized in that, during step (2) boiling, solid-liquid ratio is 1:3.5.