CN88100825A - The delignification method of the continuous producing method of cellulose pulp and/or secondary stock and the stage division of fiber - Google Patents

Abstract

The invention discloses cooking plant fiber and wood fibre or to the fiber in chemical pulp or the mechanical pulp take off this element (alternative is carried out deinking in advance) thereby, the then alternative a kind of method of producing paper pulp of bleaching.In the method, fibrous raw material is under High Temperature High Pressure behind alkaline boiling or the delignification, send in sealing, the continuous pressure pipeline system by pulp pump, concentrate again behind the liquid diluting that paper pulp extruded with a step and progressively pressurized, in the end dilute with clear water and/or bleaching liquid before the step dehydration, dehydration is cleaned at last again, and the words that need are bleached.

Description

The present invention relates to adopt chemistry and the mechanical method cooking plant fiber that combines and the wood fibre method with continuous production of cellulose paper pulp, this cellulose pulp is as the raw material of producing paper, plate, fiberboard and fibre-bearing product.This method also very is suitable for deinking, delignification and the optional bleaching of secondary stock and also can comprises the classification of fiber.

Adopt well-known sulphite process or well-known sulphite process production of cellulose paper pulp to have the history of decades.These two kinds of methods all need very big device now so that produce less expensive, and adopt the expensive of sulphite process or the required construction new cellulose of sulfate process production of cellulose device.In recent years, developed country has built some big factory of new cellulose, but after producing running, they have born big economic loss.

Some developing country is building some similar factory now, can foretell, these factories make these countries suffer big economic loss possibly in the future and increase one's load.

Its reason is that the current required expense of routine techniques of paper pulp of producing continuously is considerably beyond the receptible price in last decade cellulose market.Now, this situation concerning needs set up oneself cellulose and the developing country of paper industry unfavorable especially and can not bear.

If continuously the new factory of production of cellulose can earn a profit, then must change and upgrade cellulosic production procedure, thereby significantly reduce the investment and the capital of yearly productive capacity per ton.At present continuously the technology of producing paper pulp is mainly based on sulfate process, in recent years, this method with the sulphite process be cost in application stable development.Its reason is that sulfate process can be used most of interested fibrous raw material owing to compare with for example sulphite process.In addition, the system that sulfate process of today adopted is easy to reclaim the boiling chemicals and destroys the organic compound that is referred to as " black liquor " by fire.Therefore, think that in recent years this method is the less a kind of method of environmental pollution in the production of cellulose method.

But this method still has several important disadvantages, can be summarized as follows:

1. sulfate process has developed into the method that needs high capital and has required high production capacity, and this is the consequence of so-called " large-scale production ".This big factory tackles transport capacity mutually and infrastructure has higher requirements, but yearly productive capacity will be suffered economic loss in recent years and is not enough to earn a profit in the factory more than 200000 to 300000 tons.

2. use sulphur compound in sulfate process, this can produce bad smell and contaminated air.In addition, this method is used chloride bleaching compounds usually, and this meeting environmental emission towards periphery goes out poisonous and harmful material.

3. the factory with sulfate process is a kind of system of complexity, it comprises the technology and the mechanical part of a large amount of fundamental differences, and this factory will be divided into each workshop, carry out boiling, screening, washing and bleaching respectively, each workshop also needs heating, water supply, chemicals and discharge of wastewater system separately.

Therefore, nowadays using upright autoclaving device with the common feature of the factory of sulfate process, fiber top from this boiling vessel under can not the high concentration of pump pressure adds, fiber vertically falls in this boiling vessel according to the principle of " freely falling body " then, but then in the bottom of boiling vessel fiber dilution is become concentration pump pressure or " but blowing ".

4. carry out very slowly owing to sulfate process, thereby this method need sizable volume and floor space.This is that this makes the reaction carried out than fibre pulp in motion comparatively fast and the reaction of being carried out under the turbulent flow situation slower (" washing machine effect ") again because fibre pulp move very slowly on its path.

At temperature and pressure used during the pulp cooking usually by deciding as the fixed relationship between the pressure and temperature of the saturated vapor of the heating source of boiling vessel traditionally.

6. after boiling, use the upright tall and big washer that is connected with the recuperation of heat system of complexity to be used for " discharging " paper pulp usually.

7. during processing, by interior induction system under the relevant several different pulp densities paper pulp is diluted repeatedly and concentrate, heaviness and complex apparatus on each layer pedestal that screening, washing and bleaching etc. are tall and big by being installed in usually, heavy and expensive shop building finish.

8. must in recovery big, that need very big floor space and costliness and/or purifier, handle a large amount of water and the chemicals of outflow.

9. pulp factories comprises a lot of different machines, operation and various function, and there is the possibility of damage in all these, and requires the stock of corresponding maintenance, maintenance and comprehensive and expensive different spare parts.

The purpose of this invention is to provide production of cellulose paper pulp and/or secondary stock has the delignification method, and said method may need bleaching, may comprise deinking or other various washings.Method of the present invention does not have the very significant disadvantage that above-mentioned sulfate process has.Sulfate process is typical case's representative of prior art, is most interested and the most approaching a kind of method of the present invention.Compare with the production method of the plain paper pulp of current conventional fibre, this method has mainly been simplified process operation and process equipment, has reduced investment, area, maintenance and maintenance simultaneously.Adopt this method can fully circulate and reuse chemicals and heat energy, can obtain to be called the effect of " selecting the clothing machine " effect simultaneously again, this method from former expect the cellulose pulp finished product to carry out speed more faster than at present used conventional method.The abundant circulation of chemicals and heat energy and reuse and will guarantee that this method obtains best processing economic benefit will reduce the consumption of water in addition, thus but the waste water of limiting emission in the open water supply.The purpose that adds of the present invention is relevant with equipment of processing and procedure of processing, and the present invention can establish these and be divided into various unit, by simple inner repacking, can process all interested fibrous raw materials after the combination.A further object of the invention is to make these unit be fit to be installed on the framework of standard delivery container, thereby guarantees to assemble, transport, turn round and will install on demand that to move to the process at another place from one simple and cheap.

The present invention relates to cooking plant fiber and wood fibre or to the fiber delignification in chemical pulp or the mechanical pulp (alternative is carried out deinking) thereby, also can then bleach the method that can obtain a kind of paper pulp, this paper pulp be fit to do is produced paper, plate, fiberboard and other contains the raw material of string and lignocellulosic products.In the method, fibrous raw material is added to cooking zone, use alkaline boiling chemicals, be used in combination oxygen simultaneously, also can select to use a small amount of other additive (for example anthraquinone), form with alkaline slurry under high temperature and high pressure is carried out boiling or delignification, then removes the boiling chemicals that exists with the black liquor form in the processing of boiling processing or delignification, and above-mentioned black liquor is stored or reclaim wherein chemicals.But the method is characterized in that boiling or delignification and can select the deinking of carrying out in advance and the processing after bleaching that can select to carry out during the paper pulp raw material that will exist with the slurry form of pump pressure be transported to by pulp pump in sealing, continuous and the pressure pipeline system, above-mentioned pulp pump is simultaneously also as the mixing agitator of slurry and chemicals; When paper pulp is transported in pipe-line system, make paper pulp repeat dehydration by extruding liquid, except final step dehydration, before each step dehydration, with the liquid diluting paper pulp that has extruded and return from the dirty dehydration and/or the dirty pump pressure step cycle of this method; When paper pulp was transported in pipe-line system, the form that adopts a step or multistep pump pressure was gradually to the paper pulp pressurization, in the end before the dehydration, with the clear water of forced feed and/or bleach liquid and dilute with alternative and cool off; After the final step dehydration of pressure cooking or delignification, washing pulp is also optionally bleached paper pulp in continuous pressurized systems or under the non-pressurised state behind cold blowing or the hot blowing.

In the accompanying drawings, Fig. 1 is the flow chart of a specific embodiments of the inventive method, comprises four dehydrations and the progressively compression system of setting up from first dehydration to the, four dehydrations; Fig. 2 from left to right represents to begin to the schematic diagram of the corresponding compression system of process ends Fig. 1 from boiling processing; Fig. 3 represents the method supply of flow chart shown in Figure 1 and the Sankey schematic diagram of circulating fluid or chemical solution; Fig. 4-24 will be described in a more detailed discussion in conjunction with the introduction to this method hereinafter.

Further introduce an embodiment of this method with reference to the accompanying drawings.

See figures.1.and.2, raw material 1 and clear water 2 are joined in the pulper 3, make raw material and clear water be transported to pump P2 from pulper with pump P1 and purifier 4, at this, concentration is that the pressure on about 4% the paper pulp rises to stress level p2.Below will further introduce by a dewater unit 5(under pressure after paper pulp self-pumping P2 comes out), paper pulp reaches about 20% to 30% in this dehydration until its concentration.In the pipeline between dewater unit and pump P3, the paper pulp that took off water is diluted by the cooking liquor that booster stage and/or pressurizing and dehydrating operation from the back loop back.In addition, on the pipeline position between dewater unit and the pump P3, can also in paper pulp, add fresh chemical solutions and/or heat supply 6.The major part of the liquid 7 that extrudes from dehydration device 5 is transported to heat exchanger 8, and at this, the liquid of extrusion (waste liquid or waste water) is through the water of over-heat-exchanger and supply or perhaps be to carry out heat exchange with the waste water 9 that comes out from bleaching system.The part of the waste liquid that extrudes from dehydration device 5 also can be input in the pulper 3, is about 4% raw material paper pulp so that form concentration therein.Paper pulp enter pump P2 and and then enter dewater unit 5 before, to wherein adding the boiling chemical solutions 12 use, this solution be oneself and then pump P3(be used for next booster stage) the boiling pipe loop back.The paper pulp self-pumping p3(that arbitrarily downgrades sees Fig. 2) be transported to new pump pressure level p4, at this, pressure on the slurry is further raise and chemical steaming agent 13 is circulated back in the slurry between pump pressure level p2 and the p3, and the cooking liquor 14 with crossing that is circulated back to the pipeline position between pump pressure level p3 and the pump pressure operation p4 is taken from arbitrarily downgrade boiling pipe after the p5 of and then next booster pump.Pulp density be about 4% slurry subsequently self-pumping P4 be transported to next booster stage p5.Pump pressure level since then, slurry further are transported to compression pump P6 with the cooking liquor 15 with mistake of circulation again.By next dewater unit 16, it is about 20% to 30% that slurry dewaters until concentration at this again to slurry subsequently.Through after the dewater unit 16, paper pulp is recycled liquid 17 and dilute formation concentration and be about 4% paper pulp and be transported to next booster pump P7, and after this pump, paper pulp enters next dewater unit 18, paper pulp this dewater once more to concentration be about 20% to 30%.It is about 4% being diluted to pulp density through the paper pulp of dewater unit 18 once more with liquid 19, and last the booster pump P8 shown in being transported to.At this, liquid 19 comprises fresh water, perhaps optionally contains the waste water that bleaching system that the paper pulp that gives off from the boiling stage shown in Figure 1 will be sent to is discharged.The liquid that adds previously (19) at booster pump P8 should be colder relatively, so that make the temperature of paper pulp enough low, so that under atmospheric pressure low 100 ℃ of paper pulp its temperature when leaving pressure pipeline system, be that paper pulp will not expand, perhaps more particularly, when it leaves pressure pipeline body the it with " cold blowing ".Last dewater unit 20 shown in being sent to through the slurry of booster pump P8, and this dewater once more to pulp density be 20% to 30%.Pulp density is that 20% to 30% the slurry that took off water is discharged these systems through the cone valve on the duct end 21 subsequently.This cone valve has common structure and produces a back pressure, and it is controlled by an inflatable air bag, and its controlled pressure acts on the bottom of taper blocking mechanism.

The water yield of the pressurized water of this system is injected in control valve R2 control, and the waste water of this system is discharged in control valve R1 control.In order to control, these two valves are interrelated, and the feasible volume of the liquid in the system that is pressed into is substantially corresponding to the waste water displaced volume.

Flowcharting shown in Figure 1 the method that improves of secondary stock quality or the unbleached cellulosic method of producing annual plant.As previously described, the main concentration when carrying in pipe-line system is about 4%, and the concentration after the dehydration is about 20%-30%.The reaction member (M1, M2 and M3) of having represented three delignifications in the flow chart of Fig. 1 then is two washing procedures (on P7 and P8 positions).In the system of Fig. 1, can connect a bleachery, yet, can adopt with the front and bleach at the same method that improves the quality or boiling is introduced, the kind of used certainly chemicals and consumption Ying Yineng reach desired bleaching effect and are as the criterion.

This method can be used for various strings, as the string of bagasse, mestha, straw, rubber tree, the palmitic discarded object of production, bamboo etc., and can be used for hardwood (broad leaf tree) and cork (coniferous tree).Equally, this method also is applicable to secondary stock delignification and (can choose wantonly) bleaching.In addition, when using the secondary paper (secondary paper) that printed, the layout of body series can make the raw material deinking, and need not the additional mechanical device.This method is suitable for very wide reaction range of possibility, and this comprises the production of pulp quality at the paper pulp within mechanical pulp (MP) is to preheating method wood chip mechanical pulp (TMP) and preimpregnation preheating method wood chip chemimechanical pulp (C-TMP) to pure chemistry paper pulp scope.

As previously described, the stream of Fig. 1 and figure are suitable for the boiling of annual plant (as bagasse, grass or mestha) or the raising of secondary stock quality.If boiling saw not, hardwood or needlebush, in this method the fiberizer mechanical processing process must be arranged.At the back of fiberizer available pressure sieve, its is thick wood chip and qualified separating, and isolated thick wood chip is sent back to so that carry out chemistry and machining processes once more.This makes the multiple work-around solution that can adapt to all available fiber qualities become possibility.

Introducing at this paper as the front as described in the part of goal of the invention, also is purpose of the present invention with the device and the divided into unit of processing step own of this method of enforcement.In accompanying drawing 4, the cardinal principle of an embodiment of this method has been simplified slightly.According to Fig. 4, after pulping process 3, dipping, delignification and fiber classification effect 23 all take place in being labeled as 22 confining pressure pipe-line system, be washing 24 subsequently, before exit mechanism part 21 leaves this process system, also can select to bleach 25 and wash 26 again at the fiber that processes.

Fig. 5 has provided the flow process chart of annual plant.This flow process has three unit 27,28 and 29, and wherein there are a pulp pump and pipe-line system in each unit.With saw not, a hardwood or needlebush example producing the flow chart of paper pulp is shown in Fig. 6.Compare with the flow process of Fig. 5, be useful on the fiberizer 30,31 and 32 of machining in the flow process of Fig. 6, behind fiberizer, settled pressurized screen 33,34 and 35, they carry out chemistry and machining processes again to thick wood chip and qualified separating and the thick wood chip of separating 36,37 and 38 is sent back to.

With Fig. 5 and 27,28 and 29 these three unit shown in Figure 6 flood respectively, delignification and fiber classification be very natural, and these three operations are formed whole digestion process.

According to Fig. 4, after dipping, delignification and fiber classification effect 23, wash 24, this operation is still within the pressure system 22 of sealing.Last procedure of this cooking section is a pressurizing and dehydrating, and this operation should be carried out in pressure slurry plug inspissator shown in Figure 1.This pressure enrichment facility has detailed introduction hereinafter.

The paper pulp of boiling can be transported to a unit to wash, Fig. 7 has provided paper pulp and has been transported to the process of washing unit IV (50).In this unit, three pressure dehydrating presses are cascaded successively.What mark among the figure is three pressure screw bolt formula press, and certainly, it also is complete suitable that the pressure slurry plug inspissator that booster pump is installed with three fronts substitutes.As seen from Figure 7, by waste water injection before last pressure dehydrating press inlet of series connection of clear water or bleachery 39, before the liquid 40 of extrusion loops back the inlet of second pressure dehydrating press.The purpose of doing like this is in order to dilute the slurry after the pressurizing and dehydrating, so that it has the concentration that is suitable for further carrying (for example 40%).

According to Fig. 4, still the washed paper pulp in pressure system is passed to bleaching system.Fig. 8 has provided the mode of this conveying.By scheme shown in Figure 8, this bleaching system has three unit 51,52 and 53, and they include a pipe-line system that has booster pump separately.The paper pulp of the bleaching of coming out from last bleaching system unit VII 53 is sent to washing (as shown in Figure 4).Same three pressure dehydrating presses or three the pressure slurry plug inspissators of adopting of washing carry out (unit VIII, 54).Before the dehydration of each time pressure, liquid dilution paper pulp.In the end from washer or heat exchanger, add clear water 55 before pressure dewatering device, and be circulated to from the liquid 56 that last pressure dewatering device extrudes before the inlet of other pressure dewatering device of this pressure pipeline system.Liquid 57 in this extrusion is incorporated in the paper pulp of bleaching as if the capable of circulation time pressure pipeline system of words that needs and/or before first pressure dewatering device 58 inlets.

Leave the paper pulp 59 of last pressure dewatering device and sent to storage or papermaking.

Also can wash and (if necessary) bleaching in the system in the not supercharging of back through the paper pulp of dipping, delignification and fiber classification effect.Fig. 9 is the not sketch of supercharging washing process of this class.The paper pulp that comes from cooking section is entering the unit IV, " blowing " (if the words of wishing can through a heat exchanger 47) in 46 earlier before 48.The unit IV, 48 is wash mill unit, wherein have three modes identical with pressure washing to use dehydrating press, certainly, these three dehydrating presses are not superchargings.This nothing compress and wash wash after, paper pulp can be sent to by common mode and be bleached, i.e. not supercharging bleaching perhaps can be sent to and store or papermaking.

Having provided yearly productive capacity below is about 30,000 ton (be 100 tons of every days or per hour 4 tons) be bleaching or the data and the size of the factory of bleached cellulose paper pulp not, this factory can be in the system of this introduction and lucrative, and this is because factory takes up an area of relative with the capital input of equipment little.Its floor space of factory with so big production capacity also is suitable for building Xin Chang in developing country.

As described above, with the unit I, the 27(impregnating unit) and be respectively applied for the unit II and the III of delignification and fiber classification, promptly 28 and 29, unite with Fig. 5 and cooking section shown in Figure 6 that to use be a very normal selection, wherein can carry out the mechanical fiber grading separately with (or need not) pressurized refiner at " on the same production line ".

Hereinafter provided the example of the operating parameter of this class factory.

The table I

Unit number

Parameter I (27) II (28) III (29)

Concentration (%) 4.5 4.5 4.5

Pressure (crust) 3.0 6.0 9.0

Temperature (℃) 95 120 125

Pipe volume approximation (rice ³) 15 15 15

Holdup time (branch) 10 10 10

Add

NaOH1）3）（%） 5 5 5

NH ₄OH6）3）（%） 5 5 5

O ₂7）3）（%） 5 5 5

Cellulose manufacturing equipment equipment equipment

Wheat straw pump pump pump

Straw pump pump pump

Bagasse pump pump pump

Saw not 2) 5) pump pump+fiberizer+pressurized screen pump+fiberizer+pressurized screen

Hardwood 2) 4) 5) pump+fiberizer+pressurized screen pump+fiberizer+pressurized screen pump+fiberizer+pressurized screen

Cork 2) 4) 5) pump+fiberizer+pressurized screen pump+fiberizer+pressurized screen pump+mill pump machine+pressurized screen

Improve the quality

Secondary stock pump pump pump

（occ）

Secondary stock pump pump pump

（onp）

1), be benchmark with bone dry fiber, bagasse by dried NaOH

2) technology that dissolving part material has been improved

3) to saw not, the high value of hardwood and cork

4) the very broken wood chip of cutting

5) comparing production capacity with annual plant reduces

6) with the bone dry fiber be the NH of benchmark ₄The OH meter

7) with the bone dry fiber be the O of benchmark ₂Meter

8) old corrugation clamp paper

9) old newsprint

By the bottom of this table as seen, the raw material of being processed is depended in the use of fiberizer and pressurized screen.Yet the design of unit adapts with standard profile, has wherein kept to use the space that substitutes machinery.

The round-off work of cooking section can have dual mode, be a) with blow tank commonly used, should unite and use wash mill,, and a cooking liquor that extrudes circulated go back so that reclaim and be transported in the paper pulp then through no press-dehydrating device so that reclaim heat in the steam of emitting; B) use pressure dewatering device, the better system of closure can be simplified and obtain to this system greatly like this, also can obtain the best thermal efficiency.

At the raw material delignification first time and after carrying out fiber classification, and after bleaching again, general best the part of the washing of paper pulp as manufacturing cellulose paper sizing process.By this method, washing can be carried out in the special washing unit that 1,2 or 3 washing step is arranged in dehydration back for the first time, see the unit IV of Fig. 7,50 or Fig. 9 49.

For the bleaching of paper pulp, as long as the temperature of paper pulp pipeline is no more than 100 ℃, the wash mill of bleaching system and coupling with it all can under atmospheric pressure be operated.In this case, this method can be after the wash mill of cellulose pulp factory (be unit IV after) can adopt no pressure dehydrating press at the washing room of bleaching system.If the unit IV is to be in (Fig. 7 50) pressure under then this point is also still effective, this is because the effect that cools of the cold washings generation of introducing with clear water or from following bleaching system waste water formation, and " cold blowing " will take place pressure unit.

Yet the present invention can obtain maximum recuperation of heat amount and economy, significantly reduces total water consumption simultaneously.Like this, the situation of waste discharge also correspondingly is improved.If paper pulp after pressure system cold spurts the washing room that moves to bleaching system, then can be obtained best recuperation of heat amount.Yet this requires bleaching system and the washing room that links with it also will be used pressure apparatus.So just, exist two kinds of pressure conversion scheme.

Bleaching system and its washing room should adopt press device that many reasons are arranged.If do like this, then bleaching system and washing room thereof can adopt and make cellulose pulp and the unit identical unit used with the washing room of its coupling.

Compare with the cost of building a no pressure system, the extra cost that used machinery brings in the pressure system is little relatively.This situation also should be considered with reference to the following fact: with common cellulose pulp process the demand of capital is compared, the system of implementing the used complete pressureization of the present invention is also little to the demand of capital.

Like this, the maximum standardization that working pressure is equipped the mechanized equipment that can realize necessary usefulness in the whole system of the present invention.This is standardized in maintenance, maintenance and spare part aspect and brings significant benefit and saving again.

Like this, based on basic condition mentioned above, the washing room of pressure bleaching system and coupling with it can be as shown in Figure 8.Yet be noted that, the unit IV, 50 and the unit VIII, 54 all to adopt pressure slurry plug inspissator to be advisable.

Following table II has been introduced the running parameter of this class bleach plant operation shown in Figure 8.

The table II

Unit number

Ⅴ（51） Ⅵ（52） Ⅷ（53）

Parameter chlorination Hypo_Oopt.O Hypo+Oopt.O

Concentration in the pipe (%) 4.5 4.5 4.5

Pressure dehydration back concentration (%) 30 30 30

Pressure (crust) 10 12 14

Holdup time (branch) 10 10 10

Pipe volume (rice ³) 15 15 15

Temperature (℃) 100-120 100-120 100-120

The Hypo=hypochlorite

Opt=can select

If not chloride in the bleaching operating process, promptly only with NaOH or NH ₄OH, O ₂And O ₃, then the waste water of bleaching system can be used as washings at the washing room of cellulose pulp factory, then is recycled on the initial position of cellulose pulp technological process from the waste water that washing room comes out.

This method can be implemented by the mode of highly oneself's control.Can be poor at the steaming plant of working on the pressure-sensitive paper that a series of pulp pumps produce and bleaching system by the own controlled pressure of mode that makes the recycled back that chemical substance moves along fibre pulp in device.

This connecting each other of steaming plant and bleaching system also produces an effect, and Here it is, and device is only discharged the chemical substance of using on a position.Emission point can be further to reach, and being arranged in the intimate of this technological process is on the position that begins most." black liquor " of discharging can and/or carry out heat exchange 8(from the waste water of bleaching system and see Fig. 1 and Fig. 3 by sending to like that of having mentioned and clear water).

According to Sankey shown in Figure 3 figure, (clearly) water yield that is added in the paper pulp of bleaching as washings with the amount of the cooking liquor of mistake and end at this device of discharging this system equates substantially.

If in wash mill, used relatively large chlorine, then must make from bleaching system and the waste water of the washing room of coupling and chemical substance were interrupted before returning pulp mill and made its shunting with it.This shunting must mean that the washing room of cellulose pulp factory increases water consumption.Like this, owing to used chlorine at bleaching system, shunting must cause the increase of water consumption.However, compare, implement the used water yield of this method and significantly reduce with common cellulose pulp factory.In addition, as if the chlorine appropriateness of using at bleaching system, the liquid that then contains chemical substance can further turn back to cooking section, is used as the part of cooking liquor.

In addition, as seen from Figure 1, the supply of chemicals and/or heat 6 is before the paper pulp and nestle up on the position of pulp pump and realize, has so just obtained following advantage:

A) operating pressure has been enhanced, and so just can adopt to be higher than 100 ℃ operating temperature;

B) rising of pressure is to realize step by step by each pulp pump of arranged in series, and every through a pulp pump, pressure just is raised to next pressure stage;

C) pressure of each grade raises and make circulation and adopt the principle of fibered stream and chemicals reverse flow to become possibility simultaneously again in whole flow process;

D) raw material mixes tempestuously mutually with chemicals, and this program repeats continuously.Under the influence of the chemicals of mixing effect that is obtained and circulation, fiber " is washed " to such an extent that does not more or less contain lignin.

Among Fig. 5,6,7,8 and 9 in the drawn unit reaction pipeline 60 continue and arranging.As an example, 4 pipeline components that drawn in each unit constitute one " aggregate " together.This pipeline aggregate can be assembled on the delivery container framework of a standard with pulp pump and (if necessary) fiberizer and screen, other unit of back is also like this.Figure 10 is the sketch of this class assembly in the standard delivery container.

As seen from the above table, the holdup time in the reaction pipeline aggregate of each unit is about 10 minutes.Be an example of the size of these reaction pipelines below:

Caliber: 1 meter

Pipe volume: 15 cubic metres

Guan length overall: 18 meters

Each length of tube: 4.5 meters.

The grade of suitable pipeline is ST23-33, and its wall thickness is 13 millimeters.The pipe of this grade can bear the operating pressure of 20 crust and 175 ℃ operating temperature.Need, can select grade is that ST23-43, wall thickness are 12 millimeters pipe.

(see the voltage-controlled automatic valve of Fig. 1,2 and 3 at the valve that is used on the pipeline to circulate and return liquid under predetermined pressure, opening.Because the increase of pressure is that substep or classification realize when implementing this method, these valves will be regulated the feedback through this flow process automatically, thereby according to see Fig. 1,2 and 3 through valve R2() the determined value of amount that is pressed into the liquid (water) of this last procedure of flow process regulates the reverse flow of fibered stream and chemicals.Can be well understood to by Fig. 1 and Fig. 2 and when implementing this method, self to regulate the principle of pressure distribution.Be consistent with this programme, also will determine to discharge the amount of the black liquor of this system, thereby also determined the solid liquid degree in the black liquor from R1 through the clear water addition of R2.

Thereby the feedback controlling fiber material and the adverse current between chemicals of the voltage-controlled automatic valve between each pressurization stages in Fig. 2 in automatic control flow chart, also will control back pressure, thereby the pressure reduction of controlled pressure dewater unit, i.e. the voltage-controlled valve amount of liquid that will control dehydration degree or in paper pulp, extrude.

The table III has provided the example of the chemical technology condition of this method (comprising boiling, washing, bleaching and washing) below.

Table 3

Table 3(is continuous)

1) other alkali is as ammonia

2) mechanical defibre process is arranged simultaneously on the production line

3) AQ(anthraquinone) and surfactant, as surface-activity deinking agent (on a small quantity)

Temp. temperature

Others other

The Time time

Min. divide

From the table III as can be seen, during boiling, according to the fibrous material of sending into, the variation of temperature scope is 90-150 ℃, adopt NaOH or ammonia, oxygen and arbitrarily digesting assistant such as anthraquinone (AQ) as the boiling chemicals.According to the fibrous material of supplying with, total digestion time is 10-90 minute, yet, the delignification and the presumable deinking effect of gratifying secondary stock can take place between 2-40 minute.

Chlorine, oxygen, peroxide (oxygen bleaching) or O are used in bleaching in alkaline environment ₃Carry out, the temperature of bleaching process remains on 70-120 ℃.Cleaning between boiling and the bleaching can be carried out under 70-140 ℃ temperature, and the washing time can be 0.5-10 minute.After the bleaching, clean at last.By the table III as seen, fibre stream and liquid stream are always carried with opposite each other direction.Because whole technical process is to carry out in the airtight system of pressurizeing, so ammonia also is suitable for doing the boiling chemicals very much.

For the compression system of implementing the inventive method, pointed out that dehydration is the pressure dehydration.And pointed out that further above-mentioned dehydration can carry out in the screw extruder so-called " pressure is starched basic inspissator " or in pressurization.

In Figure 11, showed that this front has the principle of the pressure slurry plug enrichment facility of compression pump P.According to Figure 11, P _IPressure deduct the frictional resistance that slides between slurry plug wall greater than P _IIIPressure.The slurry plug of antipriming pipe inside, center will be forced out system, and to the right of figure, pressure is P simultaneously through pyramid type emission control system row _IIThe liquid of extrusion will be circulated to a place or many places (shown in the circulation pipe porch direction of arrow among the figure) of technical process upstream.

Device shown in Figure 12 can be used as the first time and dewater unit at intermittence afterwards in the system.This is consistent with dewater unit shown in Figure 11, but figure 12 illustrates, for further carrying the slurry after the dehydration in pressure slurry plug inspissator, slurry is used the technology liquid diluting in line mixer 70, process liquid returns the pressure pipeline system through one or two branch lines 71 and 72 and has the slurry of P3 pressure this moment with dilution, makes it concentration and for example is reduced to 4%.

These " pressure slurry plug inspissators " do not have moving component, its size design makes it to bear the pressure up to about 16 crust, equally, used pump can be the slurry centrifugal pump of standard, and its design is to be applicable to the suspension slurry of carrying low concentration or intermediate concentration (being the concentration range of 3-15%).As described below, when adopting the high pressure reflow flushing, need make the antipriming pipe sleeve pipe on every side and the suitable higher pressure of size of associated ping system.

Guarantee that pump can bear the pressure up to the 15-16 crust, so that bear the pressure of in system, contacting and being produced when using when several pumps.A pump lift should be in the scope of 10-20 rice.In addition, the impeller rotation of pump and diameter can be designed so that advantageously that the garden circular velocity preferably is not less than the 20-30 meter per second, mix and dispersion with the ideal that obtains between fibrous material, process liquid, used chemicals and the gas that several points add in pressure pipeline system length scope.

Yet unlike high to the requirement of outside surrounding tube, the outer most surrounding pipe has played the protection tube effect of inner tube like this as the enclosure round antipriming pipe to the requirement of strength of the internal perforated pipe in the pressure slurry plug inspissator.Therefore, exterior tube must satisfy all safety regulations of relevant pressure, promptly carries out the high pressure reflow flushing where necessary under up to 30-50 crust or higher pressure.Inner tube can be that the acid resisting steel of 1-5 millimeter is formed by wall thickness.

When implementing this method, also can adopt the pressurization screw extruder to dewater at last.

Be abbreviated as PPT for implementing pressure slurry plug dewater unit or enrichment facility that method of the present invention invents, the composition of this device is compared with the used enrichment facility of present pulp industry in design suitable simplification.When using PPT to squeeze out liquid, can obtain high relatively (up to 20-30%) fibre concentration.Above-mentioned PPT device compactness needs less space, and has and can be higher than 100 ℃ temperature and be higher than the advantage of working under the pressure of 1 crust.The natural pressure limit of PPT be 16 the crust, this be with the pressing technology system in pump and material relevant stage pressures such as routine of selected size on intensity of pipeline.This just provides the new possibility and the free degree of selecting temperature and pressure for method of the present invention, and can also make in the whole pressure system between liquid stream and fibre stream adopt countercurrent action fully and synthetically.

Pressure slurry plug inspissator comprises an inner thin-walled antipriming pipe and is placed in the non-perforated pipe of outer peripheral around this inner tube as sleeve pipe, the space that forms between internal perforated pipe and exterior tube receives because the pressure reduction between internal perforated pipe and the described space passes through water or the liquid that the hole of inner tube extrudes.

The concentration of slurry dehydration back slurry of suspending increases, and forms the slurry plug that has concentrated then in inner tube, and by the internal perforated pipe axial advance, this propelling is that the pump pressure that is applied by the end at antipriming pipe is caused to the slurry plug with the moving direction of the slurry that suspends.This pressure will be than the pressure height in the surrounding tube.

Owing to starch the port of export that plug is pushed to pressure slurry plug inspissator, just occurred to be used to new fibre-bearing suspension slurry dehydration that flows into inspissator and the new space that has concentrated, exposed new porous inner tube surface.Like this, and form slurry plug new dehydration relevant and at it after and just taken place, starch and fill in and to travel forward continuously and change to skid off the identical rhythm of antipriming pipe with it.

The tube wall of internal perforated pipe is selected to approach to such an extent that be enough to prevent that the hole on the tube wall from being stopped up by the fiber in the fiber in the slurry that suspended.Therefore, the pipe thickness of inner tube is to calculate and determine with the safety coefficient of appropriateness, and its stress that only can bear in the caused material of pressure reduction between the inside and outside pipe chamber get final product, and this stress is no more than 2 or 3 usually and clings to.Yet as mentioned above, the size of exterior tube determines must to be suitable for various safety requirements and rules of operating about pressure pipeline or vapour system under the operating pressure of the raising of expectation.

When the series connection of several pressure slurry plug inspissators is used, what can divide dewater and concentrate, the dilution of in the ranks having a rest of going forward side by side, the pressure in the system in the end one-level can reach 20 and clings to.Therefore, the design of the outer sleeve of PPT should be able to be born the operating pressure of this expectation.

Mobile in internal perforated pipe of slurry plug is to be determined by the outlet device of final stage in the technology.Outlet device can be constituted or is made of a lock chamber by the compression elasticity cone of carrying opposite with intrasystem pump pressure and that offset pump pressure, the latter is the form with pipe fitting between two valves in principle, valve replaces open and close, to discharge the part of the slurry plug that forms in the final pressure water smoking of compression system in antipriming pipe.

When the pressure cone is adopted in the outlet of compression system, the slurry plug will leave compression system under suitable condition continuously, its translational speed is uniformly substantially, and when adopting lock chamber, the rhythm of the open and close of lock chamber will determine the rhythm that the slurry plug advances and discharges in compression system.

In order to make the slurry plug be easy to move and therefrom discharge along inner dehydration antipriming pipe, be necessary with inside and outside pipe chamber between the opposite direction of pressure drop, send into pressure pulse at interval to inner dehydrating tube, cause the of short duration internal perforated pipe that is back to of the liquid that squeezes out thus.These a spot of liquid will force and self pass pore, and temporary transient reduction is near the concentration of the outside slurry plug layer of porous tube wall, the skin on the realization slurry plug warp direction and " the lubricating " between the antipriming pipe inner surface.The injection of this liquid pulse and the slurry plug that thereupon causes in antipriming pipe after prepulse moves, pulse injection stops, the normal pressure drop ratio that pressure drop ratio will be back to dehydration and concentrate.

Make slurry plug slide and therefrom discharge, must make the inwall of antipriming pipe and the frictional force between the fiber plug less than the internal shear power (axially) between the internal fiber layer in the slurry plug with the form of cohesion slurry plug along pressure slurry plug inspissator safety.

In order to ensure fill in filling in of the actual discharge cohesion of inspissator through the pressure slurry with starching uniformly, whether need this reduction friction of being undertaken by a small amount of liquid that extrudes of pulse and of short duration back pressure power " lubricate " and will depend on several operating parameters, comprising the pass of the pipe thickness of the levigate degree of the type of the concentration of the pressure reduction between the inside and outside pipe chamber, the slurry that suspends in the pressure of slurry, the pressure slurry plug inspissator, fiber and fiber, antipriming pipe and pipe, the surface state of inner tube in addition.

This pressure slurry plug inspissator and some schemes of the application in the pressure pipeline system thereof and the punching degree of internal perforated pipe and the example of pass will be described with reference to Figure 13 hereinafter.

The basic design of pressure slurry plug inspissator (PPT) as shown in figure 13.The slurry that suspends is admitted to pump 81, squeezes into pipeline 82,83 and 84 through pump 81 then.

Around pipe 83, pipe 85 is housed, from managing 85 fairleads 86.

Between pipe 82,83 and 85, seal 87 is arranged, between pipe 83,85 and 84, seal 88 is arranged.The structure of these sealings makes pipe 83 will form an inner pressure chamber 89, and chamber 89 seals with external pressure chamber 90 in the horizontal.Arrow represent respectively to suspend slurry and the water and the flow direction.

Its structure should make PPT be easy to open, and can easily replace internal perforated pipe 83 with another kind of pipe with new hole or other pass like this.

The mode of action of PPT is as described below:

At an A place, the fibre concentration of the slurry that suspends is generally 3-6%, and pressure is that the suspension slurry of the alleged intermediate concentration of p1(also can adopt, and promptly fibre concentration is 6-15%, yet this need use intermediate concentration is the slurry dedicated pump that suspends.）

By this pump 81 pressure is risen to the p2 that B is ordered, the concentration of the slurry that suspends on this aspect is identical with the A point.When suspend slurry along pipe 83 by the B point when the C point is mobile, with the hole on the flowing pipe 83.

Because manage in 83 pressure p 2 greater than outer peripheral around pressure space 90 in pressure p 4, some liquid that suspend in starching will be forced out by the hole on the tube wall, shown in arrow among the figure.The fiber that suspends in the slurry is mainly stayed in the pipe 83, therefore manages fibre concentration in 83 with corresponding raising.Like this, starch by the B point in the moving process that C is ordered in suspension, its concentration will increase gradually.The pipe 84 porch fibre concentration generally between 15-30%, it depends in the existing process conditions, as on the fine grinding degree of the degree of the type of pressure reduction (p2-p4), fiber, boiling, fiber pulp, pass, the porous surface open percentage that area accounts for total tube-surface with as described in the diameter of the parameter antipriming pipe relevant with pressure drop (p2-p3).

The liquid that extrudes is through managing 86 from managing discharge 85.

Can advantageously several PPT be connected to a continuous pressure pipeline system, because the pressure of the pump of polyphone between the slurry plug inspissator of pressure separately (PPT), intrasystem pressure will increase step by step.If each pump and PPT unit increase the pressure of about two crust, 8 unit of polyphone in system for example, the structure of whole system must can bear about 16 maximum pressures that cling to so, and this pressure also is the conventional classification limit of pump and pipeline in the compression system.

Yet, as previously mentioned, pipe 83 can be made by the tube material of relative thin, is that the acidproof stalloy of 0.5-2.0 millimeter is made by thickness preferably, can burn desirable pass on steel disc by the digital control laser machine, the steel disc after the punching polishes its inner surface earlier in bending and before being welded into pipe.The pump that adopts can be conventional centrifugal slurry pump.

End at compression system adopts a suitable tapping equipment, for example as shown in figure 15, the equalization point that the pressurized of slurry in the pressure pipeline system that can obtain suspending moves, at this moment, the pump pressure (p2) that last pressure slurry plug inspissator enters the mouth in the compression system puts on counteracting the pressure and the frictional force between slurry plug and inner tubal wall and the tapping equipment (Figure 15 shows that the tapping equipment of discharging cone form) of tapping equipment.For in pressure slurry plug inspissator, forming the movably fiber plug of cohesion, the diameter of antipriming pipe plays a very important role equally, because pump pressure caused axial force by whole pipe cross section is square increase with the pipe radius, and the slurry plug just is linear with diameter with frictional force between pipe internal surface and increases under the pressure condition situation identical with tube length.Therefore, if plug is had enough fibre concentrations, when increasing pipe diameter, just can obtain the slurry plug motion of this form at an easy rate.

Importantly the structure of pressure slurry plug inspissator should make the formed slurry plug of portion within it move in antipriming pipe and not be subjected to the obstruction of conical pipe cross-sectional form when discharging antipriming pipe.

Figure 14 has represented the serial arrangement of pressure slurry plug inspissator in airtight compression system.

At the D point, the suspension slurry that has concentrated is a kind of representational fiber pulp, and its fibre concentration is 15-30%, and this fiber pulp is pressed into dilution chamber 91, provides dilution through feed tube 92 to dilution chamber.The suspension slurry that will dilute through pump 93 is pressed into pressure slurry plug inspissator 94, dewaters once more with the described method of reference Figure 13 at this slurry that suspends.The slurry that has concentrated is promoted to flow through G point by pump pressure and enters another dilution chamber 97, and dilution chamber 97 is similar to 91, can have to starch with pressure to fill in roughly the same size of inspissator and identical design, but obviously not have internal perforated pipe.

When the slurry that has concentrated in 97 with after dilution mixes, the suspension slurry that has diluted continues by the H point and is admitted to pump 98, after this repeats concentration operation in PPT99.

Figure 15 has schematically represented as the afterbody of fibre technology or washing step and the slurry plug inspissator (PPT) that is provided with.Figure 15 shows the only part 101 that the slurry plug concentrates the port of export of organ pipe, ends preferably conical device of part 101, by means of an adjustable pressure piece, preferably air bag 102, conical device heads on the end of pipe, and air bag 102 is exerted pressure to ending part, and then the slurry stream in guard system has applied pressure.Pressure p 4 will change with the formation of antipriming pipe entoplasm plug, mode is as follows: when the slurry plug that begins to take shape at the L point in pipe when the direction of K is extended its length, fibrage will cover the increasing part on the inner surface of antipriming pipe, reduce flow rate of liquid thus, and pressure p 4 increases.When fiber plug has covered in the antipriming pipe entire portion of L to K, maximum pump pressure appears, and the liquid stream by the hole will stop substantially.Pressure by control air bag 102 can obtain an equalization point, and on this aspect, air bag puts on the pressure of cone and the pump pressure p4 balance of the frictional force on mobile and inner tubal wall and the cone surface that have deducted paper pulp.In operating process, will keep this balance automatically, because the length of slurry plug approximately is constant.When the length of slurry plug coverage hole pipe further increases and the pressure that causes importing when raising, the pressure of increase will make the slurry that has concentrated be discharged by cone with bigger amount, and will occur larger area like this has hole area, and pressure descends, and restores balance again.What Figure 16 represented is the another scheme of the last concentration step of pressurization suspension slurry system.As shown in figure 16, discharge is by discharging lock chamber control, and lock chamber is made of two ball valves or the gate valve 105 and 106 that are placed in a determining deviation in the same pipeline, and two valves alternately open and close.The path 10 7 of valve must equate with the cross section of pipe 108 at least, so that slurry is unhinderedly discharged.When the temperature of the suspension slurry (promptly treat to enter the slurry plug of normal pressure) that has concentrated from compression system be higher than 100 ℃ and when opening valve 106 valve 105 close can produce steam inside the time, can use the discharging lock chamber of this form.Slurry will be pushed out or blow out lock chamber and valve 106.Fiber in the whole volume of lock chamber blown off substantially and be full of atmospheric steam simultaneously.When shut off valve 106 and open valve 105 so that another part slurry plug when entering pipe 108, the steam of lock chamber inside or air will be compressed into corresponding to the pressure in the compression system, so that provide the space of the another part slurry plug of discharging from system.Under the specified conditions of production process, valve 105 and 106 advantageously can be designed to clack valve, flap has sharp especially cutting design to cut apart and to cut slurry and fill in.

Figure 17 represents the valve chamber device identical with Figure 16, but different be that feed pipe 110 and valve 111 are housed, when the inclusions in the lock chamber 112 can not be discharged voluntarily, use pipe 110 and valve 111.In addition, also show valve 113 and 114 among the figure respectively, close and valve 114 when opening when valve 113, valve 111 is opened, and the forced air that is provided will blow out the inclusions in the lock chamber through valve 114.Then, valve 111 and 114 cuts out, and valve 113 is opened, and as described in reference Figure 16, another part slurry plug will enter lock chamber.

Figure 18 shows and makes slurry plug at inspissator internal motion and discharge attachment device more easily therefrom.The parts of pump 115 and 116,117,118 and 119 represented formation inspissators as shown in figure 13.

Attachment device comprises that is placed in a triple valve 120 of discharging on the conduit 119 and 122, pump pressure high liquid or the gas of pipe 121 in its discharge pressure ratio slurry pipe.Flexible tube coupling 123(between the slurry pipe that separates of compression system is the gum sleeve form for example) can regulate with absorption tube in the of short duration pulsation that occurs.The device of another kind of available absorption pressure pulsation is the standard film expansion drum 124 shown in Figure 18 C.The size design of this jar should be consistent with the pressure fluctuation that expectation in the system occurs.

The mode of operation of above-mentioned attachment device is as follows:

Shown in Figure 18 A, fiber pulp is dewatered and is concentrated to take place with the described identical mode of Figure 13.Discharge in order to make slurry plug in inspissator, be easy to move and be convenient to, so that clocklike the short time is reversed pressure condition in the slurry concentrator at interval.

By the visible mode that realizes this reverse of Figure 18 B.Triple valve 120 rotates 90 ° with clockwise, close outlet 122, and make water, the mixture of chemicals or gas (for example oxygen) enter external pressure chamber 116 from opposite direction through outlet 119 with higher pressure, make the liquid that extrudes from the suspension slurry of managing 117 in early days reflux and enter pipe 117 by pore.

In situation shown in Figure 18 B, be pressed onto the amount available pressure size or the length of external pressure onset time of liquid in the pipe 117 by these holes, perhaps dual-purpose these two regulate.At slurry plug with to manage the liquid measure that the quilt of lubricate between 117 inwalls pushes back very little, it is plugged with the not significantly influence of high as far as possible fibre concentration for requiring to starch because of multiple reason.

Shown in Figure 18 B, after short-term " is lubricated " liquid ascending pipe 117, be accompanied by the motion of slurry plug, triple valve 120 returns the position shown in Figure 18 A, and at this moment, the process that concentrates and form new plug of slurry is proceeded, and the above-mentioned circulation of result repeats.

Figure 19 explanation and Figure 18 A, PPT plays the PPT of same purpose shown in 18B and the 18C, but, do not use herein triple valve and another pipe-line system with the form of pressure pulse to the internal perforated pipe injected media, fill in the liquid that extrudes the inspissator from pressure-slurry and reach identical purpose but utilize.

Figure 19 A represents, installs the pressure cylinder 126 with piston 127 at outlet 125, and piston drives 128 by driver drives as air pressure.When piston was in position shown in Figure 19 A, the slurry that suspends dewatered as previously described and concentrates.

Shown in Figure 19 B, the piston short-term movement just makes from the outflow blocking-up of managing 125 to the diagram upper position, and the pressure condition in pressure-slurry plug inspissator is changed, this is to be pressed into pressure-slurry plug inspissator owing to have the liquid of dilution and lubrication this moment of certain volume (△ V), and is shown in Figure 180 as mentioned.Elasticity duct ligation 123 or head tank 124, or the of short duration pressure pulse of similar device adjusting are shown in Figure 18 A and B.

The working method of Figure 19 C and D explanation related device, pressure cylinder herein, piston 131 and movable piece 130 have constituted the separate system of effuser 125.

Carry out thickening in the antipriming pipe of the pressure slurry plug inspissators that link with pipe 125 during, the position of valve 129 and piston 131 is shown in Figure 19 C.

When Figure 19 D explanation valve 129 short-terms were closed, piston 131 passive movement spares 130 were shifted to outlet 125.Thus, cause that the pressure condition in pressure-slurry plug inspissator reverses, the hole backflow that liquid passes antipriming pipe enters inspissator, as mentioned above.

The principle of a device of Figure 19 E and F explanation pressure-slurry plug inspissator provides reverse pulse pressure with external pressure body 132 in inspissator, external pressure body 132 is pressed on elasticity duct ligation or the connector 133; Connector 133 is inserted between the outlet 134 and connector 133 outlets 135 of drawing from pressure slurry plug inspissator, after valve 136 is conditioned, and the outlet that its can blanked-off pipe 135.Connector 133 can constitute with rubber or other elastomeric material that can bear corresponding pressure and temperature.When clean fiber and the slurry temperature that suspends lower, as when being lower than 100 ℃, for providing reverse pressure pulse such device advantageous particularly.

Figure 20 A, B, C and D show the various forms of holes on the interior pipe 117 of pressure slurry plug inspissator and fiber classification device.

Figure 20 D shows big opening but counts the pipe that the corrosion resistant metal silk screen covers in the opening outside with detailed catalogue.Figure 20 D I shows the opening (view outside managing) of metal mesh and pipe, and Figure 20 D II shows from managing interior view.

Figure 20 E, the I part has showed in dehydration the fiber suspension slurry is how to rely on mesh to concentrate by the perforate tube wall that has fine metal mesh; Figure 20 E II and I are similar, and the pulse back pressure of the liquid how fiber that the accumulation of component part slurry plug in pipe is described is forced out on the direction in manage pushes back.Can be by the liquid that mesh is pushed back in the pipe along the route of minimum resistance, be distributed between slurry plug and the inner surface of tube wall with the form of liquid layer.Reduced the friction between tube wall and slurry plug thus, the slurry plug will be promoted to travel forward by pump pressure by double-lined arrow direction among the figure.On the tube wall below silk screen, also can be without the hole, garden, and adopt the shape of tailor-tacking.For the favourable embodiment of the perforate of pipe in the slurry plug inspissator at Figure 20 A, B, the form with example among C and the D illustrates, and to these holes, favourable size and data provide in the following table IV.

The TPS technical process also can comprise the classification of fiber, and the long and short fiber of the slurry that just will suspend separately and by two separation outlets is transported to outside the pressure system.Separation is being carried out in concrete device, and it is identical that the member of this device and above-mentioned relevant pressure-slurry are filled in the member described in the discussion of inspissator.

Figure 21 A and B illustrate the schematic flow sheet of defibre, and as shown in the figure, the suspension slurry stage that surface pressure is lower in the past that pump 141 will dilute is through elasticity duct ligation 142, or other aforementioned pressure pulse equivalent device is delivered to antipriming pipe 143.But the sorting hole of pipe 143 is more much bigger than the perforate of aforementioned pressure-slurry plug inspissator.Side ring is installed pipe 144 around antipriming pipe 143 outside, the space and garden post cylinder 146 UNICOMs that form between interior pipe 143 and the outer tube 144, and 146 piston is by air-controlled driver drives, and driver has been drawn as pneumatic supply 145 among the figure.Reciprocating motion of the pistons causes pulse, and the pressure that replaces with the perforate both sides of interior pipe 143 falls.When the slurry that suspends from pump 141 towards outlet during 159 motions, pulse makes it repeatedly compress into or extract out hole respectively.Therefore, these holes of interior pipe 143 can cause screen net effect, and this effect makes the long fiber in the slurry that suspends tend to stay in the antipriming pipe 143, and short fiber passes these holes easily.Like this, short fiber can tend to the spatial concentration between interior pipe 143 and outer tube 144, after this, can be transported to outside the system by two identical pressure-slurry plug inspissators 150 and 158 of structure, this process of separating fiber is to carry out at interior pipe 143 with around between its space, and different with the process of being carried out in the pressure slurry plug inspissator is to starch in this course not have to dewater or concentrate.That is to say that the concentration of slurry is basic identical in interior pipe 143 and between interior pipe 143 and outer tube 144.

So separately after the fiber, long and short fiber two parts are sent pressure system by suspension slurry trend separately respectively, enter respectively in pressure- slurry plug inspissator 150 and 158, and these two inspissators have disposed port closing device 151 and 159 respectively.Identical shown on pressure slurry plug inspissator 150 and 158 effect and other figure.But these two inspissators (150 and 158) must have the hole of different size, this be because the bore hole size of the used inspissator 158 of long fiber part must be more used than staple fibre part the bore hole size of inspissator 150 big.

Outlet device 151 and 159 as shown, can press awl to constitute by carrying respectively, in other words, also can be made of the lock chamber of above-mentioned band valve.And such outlet device also comprises an one-way flow or pressure-control valve under advantageous conditions.

147 and 152(R ₄And R ₃) shown in valve desirable flow-rate ratio between two kinds of fibers of control respectively automatically.Like this, R is passed through in minimizing ₄Suspension slurry flow the long stapled concentration in this part is increased, thus, short fiber mainly is contained in the part of carrying by R3, and has strengthened the volume of this part.Equally, the fiber of larger proportion passes through R ₄The staple fibre that can cause larger amt is along with long fiber partly transfers out this system.

The motion and the shut off valve 156 of garden post cylinder piston 154 are synchronous, and piston 154 and piston 162 are with the counter motion operation, shown in Figure 22 A and 22B.

Two pressure balancing machines 148 and 155 have illustrated, and their suppress or part is eliminated pressure pulse in the pipe 143,149 and 157.

When piston 154 and 162 is worked under valve 156 and 161 closing state respectively; hole by pressure-slurry plug thickener 158 and the 150 used fluid pressure that backwashes is protected with overflow valve; this overflow valve is in parallel with valve 156 and 161 in the usual way, does not illustrate in the drawings.

Pressure in the pipe 144 that is caused by piston 146 changes and changes little more than the pressure in the pipe 158 and 150, this is because the resistance of bigger hole convection cell is little in pipe 143, thus, because of the motion of piston 146 when two directions produce the variation that pressure fall, equalizing pressure more promptly.Because more steady pressure falls by the thicker pipe 143 of perforate, therefore do not need the protective device of overflow type.

Be transported to the fiber fluid by managing 160 backflows from pressure- slurry plug inspissator 158 and 150 liquid that extrude, as indicated above.

In two drivers 153 shown in Figure 21 A and the B and 163, their motion frequency is always in the opposite direction worked its maintenance, does not just have parallel motion.In addition, the frequency-independent of the work of driver 145 and driver 153 and 163.And driver 145 is reciprocating motions continuously, and driver 153 and 163 carry out two short-term impulse movements according to the outlet valve of closing, pass through in the main of short duration recoil return pipe 157 of hole and 149 with the liquid that guarantees to be forced out, help thus to make slurry fill in the pressure system that moves out of, as mentioned before.If driver 145,153 and 163 moves simultaneously, just situation shown in Figure 22 A and the 22B must take place, just, each time interval inner driver 145 that works at driver 153 and 163 can carry out several reciprocating motions.

The bore hole size that is used on the pipe 143 of fiber separation must be manufactured according to the form of the slurry institute fibre-bearing that suspends.Be used for also will observing same relation by the bore hole size of long and short fiber part and staple fibre pressure-slurry plug inspissator partly respectively.In the following table IV, listed the example size of these holes.

The table IV

d D b l M

The pass bore dia is divided wide long order ²⁾

mm mm mm mm

Hole, A garden ¹⁾0.3-1.5 1-10---

The B transverse joint ¹⁾0.2-1.5 1-10 5-20 5-100-

PPT C ¹⁾Slit a=0.2-1.0 5-15 5-30 5-100-

b＝0.5-1.5

D net bag 5-50 10-80--16-60

The hole seam

The fiberoptic fiber classification ¹⁾With hole, garden 0.5-5.0 1,5-15---

The category fiber classification ¹⁾With seam 0.5-5.0 1,5-15 5-20 5-20-

The device Fibre sorting ¹⁾With screen cloth 5.0-50.0 15-300--4-40 ²⁾

Figure 22 represents that how several pressure-slurry plug inspissator goes here and there together, works simultaneously, and how to cooperate the flap arrangement of discharging slurries from system.

Figure 22 A represents to use three PPT168 that link, 169 and 170 respectively normal dehydrations and situations about concentrating, and dilute with water flows in the cut-back tank 171,172 and the liquid that extrudes flows out 179,180 and 181 situation respectively.When valve 173 is closed, stop to move axially at the inner fiber pulp plug that forms continuously of the antipriming pipe of PPT.

Figure 22 B shows and the identical systems shown in Figure 22 A that still, at valve-off 174 with after opening valve 173, the pressure among the PPT falls converse.Therefore, the slurry plug in PPT170 can arrive the outlet lock chamber between valve 173 and 174, as above faces the explanation of Figure 16 and 17.

Figure 22 A also illustrates injection device 176 respectively, 177 and 178, they push back the liquid that extrudes pressure-slurry plug inspissator 168 simultaneously respectively, 169 and 170, make the slurry plug while " being lubricated " wherein, several stock pumps apply pump pressure to slurry plug together, and the slurry plug will constantly be pushed to the outlet lock chamber simultaneously up to having compressed steam that last cleaning lock chamber retains or air till making lock chamber fill up the slurry plug.The pulse that is caused by injection device 176,177 and 178 can be cushioned 182,183 and 184 absorptions, and is open as mentioned.Valve 173 cuts out then, and valve 174 may be opened (valve 175 is used to purge lock chamber) simultaneously with valve 175, opens injection device 176,177 and 178 simultaneously and extrudes liquid to discharge by outlet 179,180 and 181 respectively again.After this, repeat identical pressure pulse circulation.Can use the pressure pulse attenuating device shown in Figure 18 and 19 in the same way.

Figure 23 represents to illustrate in greater detail in the more detailed flow chart, particularly figure shown in Figure 1 three reaction member M1, M2 and M3.As seen from the figure, tube mixer 70 is arranged before each pump, be used for mixed chemical product liquid and slurry and behind each pump, installed device, but the effect of this device is a chemicals distributor with spline structure.Also show the clear water that the liquid 7 that the first left dewater unit extrudes from Figure 23 is transferred and supplies with or carry out heat exchange once more with the issuable waste water of bleaching system before leaving system.The consumptive use control valve R2 of water and R1 control.

In order to further specify to implementing convective principles and the interpolation chemicals that this technology adopts, Figure 24 shows the technological operation principle.The diagram principle is based on following step: delignification (also deinking), to clean, and bleaching wash, and the number of circulation and recirculation depends on the number of employed pump and inspissator again.Equally, the positional number that adds chemicals also can change according to different raw materials, also depends on the fiber pulp that will produce simultaneously.As seen from Figure 24, owing in carry out this technology, used the backflow principle (to can be described as " tubular type pulp system ", be abbreviated as " TPS "), production at system's inner cellulose is integration, as a result, the clear water of not holding injection in technology is in its distance of carrying to the starting end of technology, by heating and interpolation chemicals, at first be transformed into liquid lime chloride, become cooking liquor then.Same liquid also can be from raw material on the road of carrying towards technology top the extracting DDGS, and in cooking liquor system of carrying out altogether when technology top leaves system, this all claims shown in the figure as the Sankey stream of Fig. 3.

In the process of technical process, the effect of pump is recirculation, uses cooking liquor and chemicals repeatedly, also has, and makes the chemicals and the gas that newly add mix, be distributed in the cooking liquor, stir, and " washing machine effect " in the native system, the recuperation of heat effect.

In Figure 24, A illustrates cleaning area, and B bleaches the district, C cleaning area, D dipping, delignification, deinking district.Add bleaching chemical 191 and make it become bleaching liquid in added water 190, make process fluid become boiling and/or deinking liquid by adding chemicals and heating 192 then, preamble is open.

Narrated, and compared with the conventional fibre digestion process, this process has reduced the consumption of water widely.Obtaining of this effect is owing to keep identical slurry concentration from start to finish in technical process, and because this TPS technology is carried out in continuous, sealing and pressure pipeline system, finishes dipping boiling and selective bleaching therein; Also because the pressurizing and dehydrating device of slurry dehydration is " string together " to be used, chemicals and heat have been used in recirculation repeatedly, like this, have simplified the machinery equipment of finishing the described needs of this technology, can not discharge natural water in the process of producd fibers.

When with this TBS explained hereafter paper pulp, productive rate is 50% o'clock, determines that the calculated examples of water consumption is as mentioned below.

Supposing that fibrous raw material contains 33% solid constituent, drop into TBS technology, is 2 kilograms by trunk material raw material.In the first pressurizing and dehydrating device at TPS technology top, the black liquor of extrusion contains about 1 kilogram of dissolved substance.At TBS technology tail end, promptly in the end inject water (rinse water) before the pressurizing and dehydrating, suppose that injection rate is X liter/per kilogram product fiber.Supposing that to contain amount of solid in the product cellulose identical with raw material, also is 33%, remains 1 kilogram of fiber and 1 kilogram of dissolved solid from 2 kilograms of raw materials.Solid is dissolved in and injects liquid, takes out 1 kilogram of fiber through last pressurizing and dehydrating device from system, and concurrently injected liquid and the solid that wherein dissolves can reflux and be transported to the fiber fluid and carry towards top.For keeping the essential theoretical minimum amount of using of the required condition of production of cellulose, the amount of liquid that returns, can simplify and be calculated as follows with the black liquid measure of discharging: establish and contain 15% dissolved solid in the black liquor, will be easy to evaporation, minimum theoretical liquid measure X(liter) will for:

(X15)/100=1; X=100/15=6.7 premium on currency/per kilogram fiber;

In other words, 1 ton of fiber of every production is wanted 6.7 tons of water.

To producing that cellulosic this liquid magnitude of recruitment per ton compares with the water consumption of conventional production process is low-down.

This TPS technology is to finish in continuous, as to seal compression system environment, and this just makes it be fit to very much utilize cooking liquor, as is easy to emit the ammonia cooking liquor of volatilization gas.Because of waste liquid only leaves process system from a position, the degassing of waste liquid can be controlled, and can reclaim chemicals and heat simultaneously.

From liquid (NH ₄OH solution) reclaiming the volatilization chemicals in can be with the method that adds alkali, and it can promote to displace volatilization gas.When using NH ₄When OH is cooking liquor, Powdered or pulpous state CaO or Ca(OH) ₂Can be used as and drive away NH ₃Reagent.When at this moment waste liquid leaves pressure system, emit NH ₃, NH ₃Be transported away from the process system that keeps, be absorbed in the clear water at scrubbing plant again, form new cooking liquor (NH ₄OH solution), reclaim NH simultaneously ₃Heat.

This technology comes the backflow principle of usefulness can make the regenerated fiber through various quality printings carry out the deinking processing in this technology, and need not to use extra machinery.Rely on deinking process that this processing step adds specific chemicals before paper pulp arrives the delignification operation or simultaneously, finish in slurry, if desired, bleaching is handled again.The chemicals of the promotion deinking that is suitable for is the oxidation alkene addition product of the nonyl phenol of non-ionic surface active.

Can also produce so-called " blast slurry " with this technical process, this was meant before slurry is discharged into atmospheric pressure, in advance liquid one fibre blend was not cooled to below 100 ℃ when leaving pressure system.Herein, the superiority of this technology is that it can make slurry " blast ", for example from the pressure (number that depends on force (forcing) pump the system) of higher 15～20 crust, promptly 110～150 ℃ of the temperature of lower pressure system; This is because the pressure and temperature in the TBS technology can separately be selected, and pressure and temperature is by employed saturated vapor decision in conventional fibre production.The advantage that temperature is low in this technology is that fiber is not easy the chemicals damage and failure of processed processing; And close under the vapour pressure corresponding extreme temperatures at 15～20 crust full, the situation of fiber is just different with this technology.

In Fig. 1,2 and 3, TBS technology pressurised equipment first is pump P2.But if temperature desired can make pressure correspondingly raise in the system, for continuing vaporization in the anti-locking system, also available pumps in series provides higher pressure for TPS technology.

Finish the equipment of this TBS technology and the total characteristic of technology itself and be that process is flexible, can be fit to various raw material production fiber pulp.

Use O when addressing ₂During bleaching, certainly, this has also just comprised with emitting O ₂The interpolation bleaching chemical, peroxide for example.

The above-mentioned action of backwashing in the entrance pressure power even liquid backwashes-slurry plug inspissator antipriming pipe, except plaing between fiber pulp plug and perforated pipe inwall " lubricating " effect, also has other effect.By backwashing since the pressure that backwashes is big and the hole of the high-speed liquid backflow antipriming pipe that produced in fiber and other solid can be flushed away.The pressure that backwashes is controlled with conventional overflow valve, and this valve is not shown among the figure.According to the working condition that relates to, the pressure difference of backwashing, generally in the absolute pressure scope of 10～60 crust, preferred value is than high 3～40 crust of the existing pressure of the interior pipe of PPT.

The output of implementing the technology scale device of this technical process is 100 tons of every days, and the suitable length of used PPT depends on the length of porous inner tube, and length of pipe is 2～5 meters in this, 100～400 millimeters of diameters.

Claims (22)

1, cooking plant fiber and wood fibre or to the fiber delignification in chemical pulp or the mechanical pulp (alternative is carried out deinking in advance), then a kind of method of optionally bleaching, the paper pulp that this method is produced is fit to do to produce paper, plate, fiberboard and other contain the raw material of string and lignocellulosic products, in the method, fibrous raw material is added to cooking zone, use alkaline boiling chemicals, be used in combination oxygen simultaneously, can use a small amount of other additive (as anthraquinone) if desired, under high temperature and high pressure, carry out boiling or delignification processing with the form of alkaline slurry, then remove the boiling chemicals that exists with the black liquor form in the processing of boiling processing or delignification, above-mentioned black liquor is stored or reclaim wherein chemicals; But the method is characterized in that boiling or delignification and can select the deinking of carrying out in advance and the bleaching that then can select to carry out during the paper pulp raw material that will exist with the slurry form of pump pressure be transported to sealing by pulp pump, in continuous and pipe-line system pressurization, above-mentioned pulp pump also is used as the mixing agitator of slurry and chemicals simultaneously, when in pipe-line system, carrying paper pulp, paper pulp repeats dehydration and is forced out liquid, except the final step dehydration, before each step dehydration, with the liquid diluting paper pulp that returns from the also circulation of this method downstream dehydration and/or the extrusion of pumping step, when in pipe-line system, carrying paper pulp, the form that adopts a step or the rapid pump pressure of multistep is gradually to the paper pulp supercharging, in the end before the dehydration, dilute with alternative with the clear water of forced feed and/or bleaching liquid and to cool off, after pressure cooking or delignification carry out the final step dehydration, in continuous pressurized systems or under the non-pressurised state behind cold blowing or the hot blowing, paper pulp is washed, if desired, bleach.

2, the described method of claim 1 is characterized in that using identical boiling and bleaching system that raw material is carried out boiling and bleaching.

3, claim 1 or 2 described methods is characterized in that fibrous raw material keeps identical pulp density basically when transporting, only each pressurizing and dehydrating step finished just that the back pulp density increases of short duration during in the generation change in concentration.

4, each described method in the claim 1 to 3 is characterized in that using identical main alkaline chemical in entire method.

5, the described method of claim 4 is characterized in that using NaOH or ammonium hydroxide as main alkaline chemical.

6, each described method in the claim 1 to 5 is characterized in that this method need pressurize, and its pressure is higher than the pressure of saturated vapor under the used operating temperature.

7, the described method of claim 6 is characterized in that the fibre pulp finished product discharges from the pressure pipeline system under " blast " condition.

8, each described method in the claim 1 to 7 is characterized in that each stage of this method and each pressurization steps add chemicals.

9, each described method in the claim 1 to 8, it is characterized in that using ammonium hydroxide as main alkaline chemical, before black liquor is discharged from compression system, in the black liquor that from fibre pulp, extrudes when the alkali compounds of calcic is joined the first step pressurizing and dehydrating of this method, behind the black liquor release of pressure, gaseous ammonia discharges from black liquor, and water absorbs collects the ammonia that discharges, and will join in boiling or the delignification process with the ammonia solution that this method obtains.

10, each described method in the claim 1 to 9, it is characterized in that slurry dewaters as follows, be about to slurry and compress into the outer heavy wall exterior tube thin-walled antipriming pipe of (size depends on the pressure that this method is used) that is with, the hole that makes liquid pass through inner tube by the pressure reduction that is produced between the space that forms between internal perforated pipe and internal perforated pipe and the outer sleeve radially extrudes from paper pulp, basically whole fibrous raw materials is retained in the inner tube simultaneously, thereby makes paper pulp concentrate the pulping plug.

11, each described method in the claim 1 to 10, it is characterized in that the final step pressurizing and dehydrating is equipped with the tapping equipment that concentrated paper pulp is discharged from pressure system, this tapping equipment ends part by a taper and forms, should end the end that part is placed in the pressurized systems outlet, by pressurised airbag or similarly produce pressure device pressure promoted ends part and push down the interior pressure of this system and balance each other with interior pressure.

12, each described method in the claim 1 to 11, the concentration of fibre slurry plug that it is characterized in that forming in the pressurizing and dehydrating device is carried in dewater unit by the pump pressure that pulp pump produced that is right after in front, thereby fiber pulp plug travelling forward in the pressurizing and dehydrating device makes liquid push back intermittently by pore that the outer surface at the fiber pulp plug comes boosting with the method for the inner surface generation lubrication of antipriming pipe in the interior pipe of dewater unit by the pressure reduction that intermittently reverses porous tube wall both sides.

13, the described method of claim 12, the pressurizing and dehydrating device that it is characterized in that using more than one series connection, in different pressurizing and dehydrating devices the intermittence of porous tube wall both sides pressure reduction reverse be carry out synchronously and from produce the fibre stuff system, discharge and carry out synchronously from producing fibre stuff with fibre stuff.

14, each described method in the claim 1 to 10 and 12 to 13, it is characterized in that the final step pressurizing and dehydrating is equipped with the tapping equipment of discharging lock chamber form, this lock chamber is formed by being installed at a certain distance from two valves of alternately opening greatly between the concentrated slurry outlet of pressurized systems discharging.

15, the described method of claim 14 is characterized in that discharging lock chamber and compression system, and preferably pressurized air system links, and above-mentioned pressurized systems will be opened the outlet valve of lock chamber during discharging, and the discharging lock chamber is rinsed well basically.

16, each described method in the claim 12 to 15, it is characterized in that the pressurizing and dehydrating device that uses is equipped with the used a kind of outlet of liquid that extrudes in the hole of the interior pipe of pressurizing and dehydrating device, this outlet has a triple valve, triple valve under high pressure enters liquid or gas stream at the short time intermittent running with outlet logistics of blocking extrusion liquid and the inlet of opening identical outlet at the same time, above-mentioned high pressure pushes back the liquid that extrudes previously in the hole of interior pipe, in the paper pulp carrier pipe before the lucky pressurizing and dehydrating device portal, use an elasticity tube coupling so that flexibly accept by the caused pressure pulse of the liquid that backwashes from the hole of interior pipe, or use links to each other with the pressurizing and dehydrating device and just the diaphragm pressure jar before these devices with acceptance by the caused pressure pulse of the liquid that backwashes from the hole of interior pipe.

17, the described method of claim 16, it is characterized in that the back pressure pulse provides by being installed in the piston vapour pressure cylinder or the piston hydraulic cylinder of outlet that is used for extruding from paper pulp the pressure dewatering device of liquid, or provide by the piston pressure cylinder at the arm place that is installed in described outlet, above-mentioned outlet is equipped with a used shut off valve of liquid stream that extrudes from outlet, when this valve is in the closed position, start piston pressure cylinder, the back pressure of Chan Shenging makes the hole refunds of the liquid of extrusion from interior pipe at short notice.

18, the described method of claim 16, it is characterized in that the outlet that extrudes the used pressurizing and dehydrating device of liquid from paper pulp is equipped with an elasticity tube coupling, the device that produces pressure acts on this elasticity tube coupling, outlet valve to the elasticity tube coupling and the outlet of cutting out produces pressure, thereby generation back pressure, this back pressure make the liquid that extrudes refunds in the hole of the interior pipe of dewater unit from paper pulp.

19, each described method in the claim 1 to 18, it is characterized in that before the pressurization paper pulp discharging that this method is produced, make paper pulp by have corresponding gross porosity and be with form in the pipeline of outer tube of external jacket of pipe, in the hole He outside the hole, apply hydraulic impulse, thereby making, the fiber of weak point flows out gross porosity and enters in interior pipe and the formed space of outer tube chuck, slurry than staple fibre distributes from the outer tube chuck, before this method discharging paper pulp, make slurry pass through last pressurizing and dehydrating device, make long stapled slurry pass through a final pressurizing and dehydrating device simultaneously, and before this method discharging paper pulp, paper pulp is dewatered from the porous inner tube of fiber classification device.

20, the described method of claim 19 is characterized in that the Kong Yaoda of the interior pipe of the pressurizing and dehydrating device that the boring ratio long fibered pulp of interior pipe of fiber classification device is used, and the Kong Yaoda of the used pressurizing and dehydrating device of the short slurry of the latter's boring ratio fiber.

21, the used device of each method in carry out claim 1 to 20, it is characterized in that this device is to depress the used pressurizing and dehydrating device of slurry plug that provides concentrated adding, it comprises the porous inner tube that is with outer tube, outer tube its end and interior pipe be sealing and by can constituting than the material that porous inner tube bears higher pressure, this outer tube is equipped with one or more inlet tubes and pushes back in the space that porous inner tube and outer tube form by entering interior pipe in this space and by this space in its hole with the liquid that is used for being collected in the porous inner tube liquid that extrudes from paper pulp and is used for off and on extruding or other scouring media.

22, the described device of claim 21 is characterized in that the hole is made up of the hole on the interior pipe, has the silk screen or the screen cloth of sieve aperture on this hole covers, and its sieve aperture is basically less than the hole on the tube wall.

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