Background technology
Pulping and paper-making is the industry that never decays; It also is the pillar industry of Chinese national economy; But paper industry is again one of main industries of environmental pollution; Its wastewater emission amount occupies the 3rd in industrial wastewater, so the technological process of treating papermaking technology is the research focus of domestic and international paper industry and environmental protection circle always.
Though it is the effective ways that solve black digestion liquid at present that firing method alkali reclaims, one-time investment is huge, and operating cost is high.In addition, traditional alkali recovery technology has not only been burnt available organic matter in the black liquor, also produces a large amount of pernicious gases simultaneously and causes secondary pollution.In addition, slurrying but has very big inadaptability to alkali recovery technology to the paddy and wheat grass, causes the huge waste of the paddy and wheat grass papermaking resource of China's abundant.
In the prior art; To make every effort to fundamentally to overcome or reduce the technical scheme that black liquor of pulp making pollutes a lot of about improving paper-making pulping process; Patent of invention " no boiling drug immersion ryegrass pulping technology " like notification number CN1621610; The no boiling method that this process using chemicals soaks is handled wheat straw class paper making raw material and is produced paper making pulp; Soak medicine and be made up of sulphur, magnesium carbonate, aluminium hydroxide and magnesia, immersion medicine operating weight proportioning is: wheat straw: caustic soda: hydrogen peroxide: soak medicine: water=100: 5-15: 1-5: 0.1-1: 60-85.
Application for a patent for invention " environment-friendly pulping agent and technology " like application number 200610114218.5; Its pulping agent is made up of animal oil, neopelex, alkaline hydrogen peroxide, sodium sulfite, the potassium ferricyanide; Wherein, alkaline hydrogen peroxide is made up of NaOH and hydrogen peroxide.Pulping process comprises: spray immersion, shove, add water mill slurry, shove, add sour defibrination, screening, washing, bleaching.The environment-friendly pulping agent of this invention is short to the grass soak time, and this pulping agent can recycling use, environmentally safe.
The application for a patent for invention of application number 200810030459.0 for another example " alkaline process zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process "; Be in digestion process, to add to use twin-screw rubbing extruding pulper in catalyst and the pulping process; The soda pulping process digestion process can be carried out under normal pressure or low pressure, and do not have residual alkali in the black liquor.In boiling, washing and the bleaching pulping process, slurry can keep higher concentration all the time.
The common problem that exists is that pulping process still need be used chlorine-containing bleaching in the technique scheme.
Summary of the invention
The objective of the invention is to have the technical problem of chlorine-containing bleaching and disclose a kind of pollution-free production technology of string paper pulp to technique scheme.
Pollution-free production technology of the present invention is made up of following steps:
(1) preparation of coarse particles: discongest reaction through pretreated plant fiber material, with plant fiber material with discongest agent in discongesting device by 1: the weight part ratio of 3-4 mixes, and discongests reaction temperature 30-90 ℃, reaction time 1.5-3 hour; The component and the weight portion composition thereof of discongesting agent are NaOH 0.5-3, oxidant 0.2-2, water 80-90, stabilizing agent 0.1-0.8 and auxiliary agent 0-0.8; Said oxidant is hydrogen peroxide or SODIUM PERCARBONATE; Said stabilizing agent is sodium metasilicate or diethylene triamine pentacetic acid (DTPA); Said auxiliary agent is the compound of AEO, APES, sodium alkyl benzene sulfonate, and its weight part ratio is an AEO: APES: sodium alkyl benzene sulfonate=1-3: 2-5: 1-3;
(2) defibrination is handled: coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled;
(3) desanding is handled: the middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled;
(4) Screening Treatment: the thin pulp after the desanding removes impurity such as burring joint through pressurized screen;
(5) concentrated, shove is handled: the thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
Pulping process of the present invention is further comprising the steps of:
Said plant fiber material is a kind of or wheat straw, straw, cotton stalk, bagasse a kind of of timber, reed, bamboo.
The preliminary treatment of said timber or reed or bamboo be said raw material through fragmentation in fermentation vat by raw material: the weight part ratio mixed soaking of soak=1: 3-4 1-4 hour; It is NaOH 0.5-3, oxidant 0.2-2, auxiliary agent 0.1-0.8 and water 80-90 that the component of soak and weight portion thereof are formed; Said oxidant is hydrogen peroxide or SODIUM PERCARBONATE; Said auxiliary agent is the compound of AEO and sodium alkyl benzene sulfonate; Weight part ratio is AEO: sodium alkyl benzene sulfonate=1-3: 2-5, and isolated soaked in water is used to prepare soak or liquid is discongested in preparation after the said immersion after precipitation process.
Saidly be used for timber or reed or bamboo to discongest that the component of agent and the weight portion thereof of reaction form be NaOH 0.5-3, oxidant 0.2-2, water 80-90 and stabilizing agent 0.1-0.8.
The preliminary treatment of said wheat straw or straw or cotton stalk or bagasse be prescind, pressure break and/or remove dust and impurity.
Saidly be used for wheat straw or straw or cotton stalk or bagasse to discongest that the component of agent and the weight portion thereof of reaction form be NaOH 0.5-3, oxidant 0.2-2, water 80-90, stabilizing agent 0.1-0.8 and auxiliary agent 0.1-0.8.
Said defibrination with concentrate, extract isolated middle section water in the processing procedure is used for plant fiber material after precipitation process preliminary treatment, preparation and discongest liquid and dilution desanding water.
Said sediment of discongesting liquid and middle section water is pressed into structural lumber after extracting.
Beneficial effect of the present invention and advantage are: the auxiliary agent that this method is used has very strong wetting, osmosis; Can impel NaOH rapidly that fiber surface is wetting and be penetrated into inside with the active oxygen (HOO) that hydrogen peroxide produces under the distintegrant effect; Make in the lignin chromophore be decomposed into low molecule colourless substance simultaneously in the lignin degradation stripping, like monocarboxylic acid or dicarboxylic acids.The stabilizing agent that this method is used can have the advantages that the shielding of color development complexing of metal ion to reduce that chromophoric group produces, thereby has improved the whiteness of slurries.Also owing to influence of surfactant in the auxiliary agent, the lignin that can will deviate from, colloid etc. are distributed in the water equably, prevent to be adsorbed by string once again.Reason to sum up, method of the present invention can be saved pulp washing and bleaching process, and the waste water of pulping process can utilize through simple process fully more simultaneously, does not therefore produce with serious pollution black liquor of pulp making.Method of the present invention has the outstanding advantage that timber, reed, bamboo soak that pretreatment time is short, energy consumption is low, equipment investment is little and is specially adapted to wheat straw, employing straw slurry.
The specific embodiment
Further specify the present invention below in conjunction with embodiment.
Embodiment 1:
With timber---poplar is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Poplar is through being broken for bar; The poplar bar is pressed raw material in fermentation vat: the weight part ratio mixed soaking of soak=1: 44 hours; Soak is by NaOH 3 weight portions, oxidants hydrogen peroxide 2 weight portions, by auxiliary agent 0.1 weight portion, water 90 weight portions that AEO and sodium alkyl benzene sulfonate compound are formed, and forming the AEO of auxiliary agent and the weight part ratio of sodium alkyl benzene sulfonate is 2: 3.
Soak poplar bar raw material after 4 hours deliver to discongest jar with discongest liquid in discongesting device by raw material: the weight part ratio of discongesting liquid=1: 4 mix coarse particles.Discongest reaction temperature 50-90 ℃, 3 hours reaction time.Discongesting agent is made up of NaOH 3 weight portions, oxidants hydrogen peroxide 2 weight portions, water 90 weight portions, stabilizing agent sodium metasilicate 0.8 weight portion.Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The leading indicator of embodiment 1 bleaching refining is following:
Index |
Whiteness |
Hardness |
Beating degree SR |
Yield % |
Weight in wet base |
PH |
|
75.86 |
13.3 |
23 |
70 |
2.7 |
7 |
Among the embodiment 1, soak the isolated soaked in water in back and after precipitation process, be used further to prepare soak and discongest liquid with the thick middle section water of extruding of starching.When preparing soak or discongesting liquid, should mend to limit value according to the remaining content of NaOH, oxidant, stabilizing agent and auxiliary agent in the water.
Soaked in water and middle section water also can be used for preliminary treatment, the preparation of plant fiber material and discongest liquid and dilution desanding water
Embodiment 2:
With the reed is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Reed is pressed raw material through fragmentation in fermentation vat: the weight part ratio mixed soaking of soak=1: 31 hour; Soak is by NaOH 0.5 weight portion, oxidants hydrogen peroxide 0.2 weight portion, by auxiliary agent 0.1 weight portion, water 80 weight portions that AEO and sodium alkyl benzene sulfonate compound are formed, and forming the AEO of auxiliary agent and the weight part ratio of sodium alkyl benzene sulfonate is 2: 3.
Soaking reed raw material after 1 hour delivers to through auger conveyor and discongest jar and discongest liquid and discongesting in the device by raw material: the weight part ratio hybrid reaction of discongesting liquid=1: 3 gets coarse particles.Discongest reaction temperature 30-50 ℃, 1.5 hours reaction time.Discongesting agent is made up of NaOH 5 weight portions, oxidants hydrogen peroxide 2 weight portions, water 80 weight portions, stabilizing agent sodium metasilicate 1 weight portion.Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The leading indicator of embodiment 2 former slips is suitable with embodiment 1 former slip.
Among the embodiment 2, soak the isolated soaked in water in back and after precipitation process, be used further to prepare soak and discongest liquid with the thick middle section water of extruding of starching.When preparing soak or discongesting liquid, should mend to limit value according to the remaining content of NaOH, oxidant, stabilizing agent and auxiliary agent in the water.The middle section water that the thickener and the machine of extracting come out is used for the preparation of desanding thin pulp after precipitation process.
Embodiment 3:
With the bamboo is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Bamboo is pressed raw material through fragmentation in fermentation vat: the weight part ratio mixed soaking of soak=1: 43 hours; Soak is by NaOH 2 weight portions, oxidants hydrogen peroxide 1 weight portion, by auxiliary agent 0.5 weight portion, water 85 weight portions that AEO and sodium alkyl benzene sulfonate compound are formed, and forming the AEO of auxiliary agent and the weight ratio of sodium alkyl benzene sulfonate is 2: 3.
Soaking bamboo raw material after 3 hours delivers to through auger conveyor and discongests jar and discongest liquid and discongesting in the device by raw material: the weight part ratio of discongesting liquid=1: 4 mix coarse particles.Discongest reaction temperature 40-70 ℃, 2.5 hours reaction time.Discongesting agent is made up of NaOH 2 weight portions, oxidant SODIUM PERCARBONATE 1.5 weight portions, water 85 weight portions, stabilizing agent diethylene triamine pentacetic acid (DTPA) 0.5 weight portion.Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The leading indicator of embodiment 3 refinings is suitable with embodiment 1 former slip.
Among the embodiment 3, soak the isolated soaked in water in back and after precipitation process, be used further to prepare soak and discongest liquid with the thick middle section water of extruding of starching.When preparing soak or discongesting liquid, should mend to limit value according to the remaining content of NaOH, oxidant, stabilizing agent and auxiliary agent in the water.The middle section water that the thickener and the machine of extracting come out is used for the preparation of desanding thin pulp after precipitation process.
Embodiment 4:
With wheat straw or straw is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Wheat straw or straw through prescind, pressure break, removal dust and impurity delivers to and discongests jar and discongest liquid and discongesting in the device by raw material: the weight part ratio of discongesting liquid=1: 4 mix coarse particles.Discongest reaction temperature 50-80 ℃, 3 hours reaction time.Discongesting agent is made up of NaOH 2 weight portions, oxidant SODIUM PERCARBONATE 1.5 weight portions, water 85 weight portions, stabilizing agent diethylene triamine pentacetic acid (DTPA) 0.6 weight portion and auxiliary agent 0.8 weight portion; Auxiliary agent is the compound of AEO, APES, sodium alkyl benzene sulfonate, and its weight ratio is an AEO: APES: sodium alkyl benzene sulfonate=1-3: 2-5: 1-3.
Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The leading indicator of embodiment 4 bleaching refinings is following:
Index |
Whiteness |
Hardness |
Beating degree SR |
Yield % |
Weight in wet base |
PH |
|
75.3 |
13.1 |
29 |
63 |
2.5 |
7 |
Embodiment 5:
With the cotton stalk is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Cotton stalk through prescind, pressure break, removal dust and impurity delivers to and discongests jar and discongest liquid and discongesting in the device by raw material: the weight part ratio of discongesting liquid=1: 6 mix coarse particles.Discongest reaction temperature 60-90 ℃, 2.5 hours reaction time.Discongesting agent is made up of NaOH 2.8 weight portions, oxidants hydrogen peroxide 1.9 weight portions, water 90 weight portions, stabilizing agent diethylene triamine pentacetic acid (DTPA) 0.4 weight portion and auxiliary agent 0.5 weight portion; Auxiliary agent is the compound of AEO, APES, sodium alkyl benzene sulfonate, and its weight ratio is an AEO: APES: sodium alkyl benzene sulfonate=1-3: 2-5: 1-3.
Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The former slip leading indicator of embodiment 5 is suitable with embodiment 4.
Embodiment 6:
With the bagasse is the paper pulp plant fiber material.Every weight portion is 1000kg among the embodiment 1.
Bagasse is delivered to and is discongested jar and discongest liquid and discongesting in the device by raw material through removing dust and impurity: the weight part ratio of discongesting liquid=1: 4.5 mix coarse particles.Discongest reaction temperature 70-80 ℃, 2.5 hours reaction time.NaOH 0.5 weight portion, hydrogen peroxide 2, water 80-90, sodium metasilicate 5 and auxiliary agent 0-3; Discongesting agent is made up of NaOH 1.9 weight portions, oxidants hydrogen peroxide 2 weight portions, water 90 weight portions, stabilizing agent sodium metasilicate 6 weight portions and auxiliary agent 0.1 weight portion; Auxiliary agent is the compound of AEO, APES, sodium alkyl benzene sulfonate, and its weight ratio is an AEO: APES: sodium alkyl benzene sulfonate=1-3: 2-5: 1-3.
Coarse particles through press master dewater to concentration be 30-35%, the coarse particles after the dehydration is got into joins stock tank, add water and be mixed with the middle underflow that concentration is 8-12%, middle underflow is carried out defibrination and is handled.The middle underflow of handling through defibrination adds water and is mixed with the thin pulp that concentration is 0.5-1%, and thin pulp carries out desanding through desander to be handled.Thin pulp after the desanding removes impurity such as burring joint through pressurized screen.Thin pulp after screening gets into thickener and concentrates, and extracts processing through press master again, and obtaining concentration is the bleaching refining that is used for papermaking of 30-40%.
The former slip leading indicator of embodiment 6 is suitable with embodiment 4.
Embodiment 7:
The defibrination of above each embodiment handled and concentrates, extracts after the processing procedure isolated middle section water is used to prepare soak after precipitation process or liquid is discongested in preparation or the desanding of preparation thin pulp is handled.When liquid is discongested in preparation soak or preparation, should mend to limit value according to the remaining content of NaOH, oxidant, stabilizing agent and auxiliary agent in the middle section water.
Embodiment 8:
With above each embodiment discongest liquid and with defibrination, concentrate, the sediment of isolated middle section water is pressed into structural lumber after extracting in the shove processing procedure.