CN1332293A

CN1332293A - Pulping and paper-making process with palm shell as raw material

Info

Publication number: CN1332293A
Application number: CN 01126541
Authority: CN
Inventors: 周汉臣; 仇刚; 刘以顺
Original assignee: SHANGHAI PUHAO ECONOMIC & TRADE Co Ltd
Current assignee: Shanghai Puhao Pulp Making Paper-Making Engineering Co.,Ltd.
Priority date: 2001-08-24
Filing date: 2001-08-24
Publication date: 2002-01-23
Anticipated expiration: 2021-08-24
Also published as: MY129493A; CN1150365C

Abstract

The invention involves a kind of method for making pulp and paper using hull of palm tree as raw material, and belongs to the field of papermaking technique. By preprocessing hull, cooking, separating black liquor, washing, cleaning, pulping and paper making etc technical steps, all sorts of papers having met the specifications can be made out. This kind of paper has good physical capabilities that can be used as Kraft wrapping and cultural paper with middle or top grade. The invention discovers new raw material for papermaking and changes trash to treasure.

Description

With the palm shell is the pulp and paper making method of raw material

Technical field

The invention belongs to pulp technology for making paper, being specifically related to a kind of is the pulp and paper making method of raw material with the palm shell.

Technical background

Palm is planted large in number and widely distributed in the world.Palm fruit is after squeezing oil plant, and its shell slag is generally abandoned as waste material.People spread throwing to it at the mountain valley woodland for a long time, the fermentation of giving free rein to, or concentrate the stacking back to burn with fire, do the fertilizer use.To cause pollution thus to environment.Countries of some a large amount of plantation palms, as Malaysia etc., handling a large amount of palm shells has become a great society problem.For this reason, people are seeking to handle and utilize the various approaches and methods of palm shell slag.For example, the applicant once utilized this shell to produce medium density fibre board (MDF) and succeedd, but the amount of processing shell slag is not enough far away.The present invention proposes with palm shell as the pulping and paper-making new raw material, and proposed corresponding production method, make a silk purse out of a sow's ear, benefit the society, still do not have relevant report in the world so far.

Summary of the invention

The objective of the invention is to propose a kind of is the method for the pulping and paper-making of raw material with the palm shell, thereby makes a silk purse out of a sow's ear, and a kind of new raw material of pulping and paper-making is provided.

The present invention at first analyzes the chemical analysis of palm shell.After handling through preliminary degreasing, washing, oven dry, make it to become and be shell slag silk, analyze its chemical analysis and be: moisture content 9.4%, ash 3.33%, the hot water extract 7.09%, benzene ferment extract 1.65%, this quality 12.71%, holocellulose 80.04%.As seen, it is learned composition and has approached the fiber of reed in the grass fiber, and content of lignin is low than reed again, and fibre morphology length and width degree is shorter, and the fiber interweaving performance is good, illustrates that it can be used as a kind of desirable feedstock of papermaking.According to palm shell contain certain grease with and the composition of chemical analysis, it is the papermaking process of raw material that the present invention proposes with the palm shell, its concrete steps are as follows:

1, preliminary treatment.The palm shell raw material that comes out from oil press for extracting juice factory is carried out preliminary treatment, comprise steps such as cleaning, preliminary degreasing, oven dry, chopping, dedusting.

2, boiling.To deliver to the pre-dipping machine of spiral through pretreated palm shell raw material, and add boiling, send into the boiling vessel boiling again, make shell slag pulp solution with chemicals (claiming soup in the industry).Boiling vessel can adopt spherical, and the revolution that can circulate also can be adopted vertical fixingly, and it circulates the soup in the container by external drawing liquid, and the boiling vessel of two kinds of patterns can mix soup and raw material.In this processing step, the used chemicals of boiling is NaOH, and addition is 18-22% of a dried palm shell raw material weight; The weight ratio of soup and raw material (being called for short the soup ratio) is 1: 4-1: 6, and the dress pot amount of shell slag is 120-140kg/m ³, cooking pressure from low to high, the boiling maximum pressure is 0.6Mpa, the high pressure temperature retention time is 5-6 hours.

In this processing step, the used chemicals of boiling also can be NaOH and Na ₂The mixture of S, Na ₂S is about 1/3 of NaOH.

Shell slag raw material and soup through the High Temperature High Pressure boiling, carry out chemical reaction in boiling vessel, organic matter dissolving under the highly basic effect, degraded and saponification such as the lignin in the raw material, polysaccharide, grease, and keep cellulose and hemicellulose in the raw material as much as possible.Behind cooking reaction, the shell slag has become pulp solution, under high pressure feed bin is arrived in pulp blowing out then, stores.

3, black liquid extraction.The pulp solution that is obtained by boiling is a mixture, wherein includes cooking liquor and dissolved organic matter etc., and color darkly is so be called black liquor.In this processing step, first Shen knotter is removed the thick stem foreign material that a part is situated between by steaming in the pulp solution, then by the vacuum pulp washing machine group, adopts the method for countercurrent washing, and black liquor is separated from slurry.Above-mentioned vacuum pulp washing machine group can be composed in series by 3-5 vacuum pulp washing machines, is generally 4.Through this processing step, the black liquid extraction of the overwhelming majority can be come out.Separate clean more well more, general recovery rate is about 80% (still have the black liquor about 20% still to mix with slurry, will further remove in the road technology down); The concentration and the temperature of the black liquor that extracts are high more good more, and the concentration of general final stage black liquor is 6-7 ° of Be (Baume degrees), and temperature＞60 ℃ are so that to the recycling of black liquor.

4, washing, purification.To the pulp liquor thin up of handling through step (3), further remove wherein impurity, silt etc. with centrifugal sand removing machine and pulp screen, carry out processed with thickener then, further wash residual black off.Through diluting repeatedly several times, dewatering, until remaining black liquor is cleaned.Generally can determine whether washing stops by measuring fixed its remaining basicity of pH value of slurry or side.

5, making beating, papermaking.Send the paper pulp through step (4) double plate of many series connection to grind the processing of pulling an oar.The purpose of this step is to make the shell fiber further discongest, divide silk, brooming and cut-out, to satisfy the requirement that different paper kinds are produced.The making beating situation generally uses Xiao third constellations beating degree (° S.R) to represent.The beating degree of this technology is controlled to be 40～50 ° of RS.Generally can be according to all differences that require of different paper kinds.Beating degree is high more, and the paper pulp drainability is slow more, fiber brooming, divides silk good, copy into the doing of paper, warm intensity height, but gas permeability is relatively poor.

Through beating process, according to the different requirements of paper kind, add corresponding chemical auxiliary agent and filler, regulate pH value, put storage pool and store, use for paper machine.In this technology, the chemical assistant of adding is: rosin: 0.8-1.0% (for palm shell weight), alum: 5-7% (ditto).According to the requirement of paper kind, also can add other paper pulp (for example needlebush, leaf wood paper pulp etc.) in addition, mix with it by different proportion.

Above-mentioned paper pulp is diluted at mixing pit again, dilute by being pumped into blending bin again, be sieved into header box through rotor, to the paper machine head box, online forms page again, becomes paper after press dewatering and oven dry.Then, according to customer requirements, cut, rewinding the roll web or the paperback paper that become certain specification to require.

In the above-mentioned steps, the effect of head box is to guarantee that paper pulp fiber evenly distributes, and makes its horizontal section flow unanimity that flows to paper machine, and evenness is good, the sheet paper products of full width weight unanimity to guarantee to produce.

Wire-cloths mainly is the dehydration moulding.From the wet end to the squeezing, the l Water Paper page or leaf is further strengthened dehydration with mechanical means.When reaching 40% left and right sides, advances web dryness the oven dry of oven dry portion.Mass dryness fraction reached 92-95% when page came out from oven dry portion.

Among the present invention, the equipment of use is identical with common pulping and papermaking equipments.

What said method production obtained is unbleached paper.Produce blank sheet of paper if desired, also need the paper pulp through washing, purification is carried out the processing of bleaching process.Bleaching can be taked chlorination-alkali treatment---H usually ₂O ₂Three sections bleaching process of method:

First section chlorination, paper pulp leads to chlorine, most of residual lignin is become chlorlignin and dissolves, and removed with washing methods.

Paper pulp is further cleaned in second section alkali treatment, purpose, regulates the paper pulp pH value.

The 3rd section H ₂O ₂Bleaching because the oxidation delignification is more effective than chlorination delignification, removes delignification with method for oxidation so that obtain better effect.

Whiteness after floating＞more than 75%, produce needs to satisfy all kinds of cultural papers.Bleaching also can be selected wherein two sections.The paper pulp of handling through bleaching is sent to making beating, papermaking operation.

Among the present invention, raw material is except palm shell, and palm itself and branches and leaves thereof also can be used as raw material of the present invention, and process is identical.

Paper by manufacturing of the present invention has good performance, can be used as kraft wrapping and various medium-to-high grade cultural paper, and the key technical indexes of finished product sees the following form 1:

Table 1

The specific embodiment

Below by two embodiment, further describe the present invention, its equipment is common paper production line equipment.

Pretreatment of raw material. To the palm shell raw material clean, preliminary degreasing, through manually shearing, sheared length is 25-30mm, Remove the impurity such as particle, dust, and after raw material mixed, be stored in the polybag for subsequent use.

Boiling: the chemical analysis of known palm shell raw material is determined cooking schedule thus near grass as raw material. After the boiling Slurry through black liquid extraction, through 60 mesh sieves washings, dehydration, and in the valley beater, beat to half stuff. Two embodiment 1# With boiling, the half stuff process conditions of 2# with the results are shown in Table 2:

Table 2

Annotate: assay method all adopts national standard method to carry out.

Bleaching. H₂O ₂Be used for association with pulp bleaching and have that retention of whiteness is good, Technological adaptability is strong, process is simple, contaminated wastewater Many advantages such as light. H is adopted in this experiment₂O ₂Bleaching is to improve as far as possible monkey grass slurry whiteness. Bleaching is at the hot water bath In carry out. Slurry places stainless steel cylinder, adds a certain amount of agent and auxiliary agent of floating, control bleaching temperature and bleaching time, bleaching Fully filtering stock is for subsequent use. Conditions of bleaching and the results are shown in following table 3:

Table 3Gained is floated slurry, after making beating, copies again paper, measure its physical property by national standard, the results are shown in following table 4:

Table 4:

Claims

1, a kind of is the pulp and paper making method of raw material with the palm shell, it is characterized in that concrete steps are as follows:

(1) preliminary treatment, to the palm shell raw material clean, preliminary degreasing, oven dry, chopping, dedusting;

(2) boiling is delivered to the pre-dipping machine of spiral with raw material, adds the boiling chemicals, sends into the boiling vessel boiling again, makes shell pulp solution; Conditions of cooking: the chemicals of adding is NaOH, and addition is 18-22% of a raw material weight, and the soup ratio is 1: 4-1: 6, and dress pot amount is 120-140kg/m ³, the boiling maximum pressure is 0.6Mpa, the high pressure temperature retention time is 5-6 hours;

(3) black liquid extraction, a part of being removed in the pulp solution by knotter is not steamed the thick stem foreign material that are situated between earlier, then by the vacuum pulp washing machine group, adopts the method for countercurrent washing, and black liquor is separated from slurry, and recovery rate is about 80%;

(4) washing, purification to the pulp liquor thin up through step (3), are further removed impurity, silt etc. with centrifugal sand removing machine and pulp screen, carry out processed with thickener then, further wash residual black off; Through several times repeatedly, clean until the remaining black liquor of slurry;

(5) making beating, papermaking send the paper pulp through step (4) double plate of many series connection to grind the processing of pulling an oar, and beating degree is controlled to be 40-50 ° of RS; Then, according to the requirement of different paper kind, add corresponding chemical auxiliary agent, filler, regulate pH value, the chemical assistant of adding is: rosin: 0.8-1.0%, and alum: 5-7%; With above-mentioned paper pulp dilution, be sieved into header box through rotor again, to the paper machine head box, online forms page again, becomes paper after press dewatering and oven dry.

2, pulp and paper making method according to claim 1 is characterized in that the paper pulp through washing, purification is carried out bleaching process to be handled.

3, pulp and paper making method according to claim 2 is characterized in that bleaching and takes chlorination-alkali treatment-H ₂O ₂Method tri-stage bleaching technology.