JPH09508945A - Method for peroxide bleaching of cellulose material and lignin cellulose fibrous material - Google Patents

Abstract

A method for bleaching cellulosic and lignocellulosic pulp using hydrogen peroxide as a bleaching reagent, utilizes a three stage reaction, viz. two short high temperature peroxide bleaching steps (50,160) at a pressure sufficient to suppress boiling and an interstage treatment (90) including a longer atmospheric pressure reduced temperature bleaching step. The two short peroxide bleaching stages include the steps of introducing pulp, at a consistency of 10%-18%, to a mixer (20,130) in which the pulp is heated to a temperature above 100 degree Celsius; adding sufficient sodium hydroxide (32,142) to bring the pulp to a pH of 8.5; adding sufficient hydrogen peroxide (33,143) to equal from about 0.5%-5.0%, by weight, of the pulp; passing the pulp through a pressurized reactor column (50,160) at a rate providing a reaction time in the column of less than 45 minutes, cooling the pulp and discharging the cooled pulp to a washer. It may be desirable to introduce the pulp to a mixer and add alkali to reactivate residual hydrogen peroxide by bringing the pulp to a pH of at least 9 after the first bleaching stage, deposit the pulp in a reaction tower and allowing the reaction to proceed until a substantial portion of the residual hydrogen has been consumed. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION Peroxidative bleaching method of cellulosic material and lignin cellulosic fibrous material TECHNICAL FIELD The present invention relates generally to bleaching of lignin cellulosic material in the pulp and paper industry, especially pulp bleaching treatment using hydrogen peroxide. Process for improving the performance of. The invention is particularly useful when used in connection with a bleaching process to produce pulp that is bleached without the use of chlorine compounds. Background Art The pressure to remove chlorine compounds in pulp bleaching and reduce negative environmental impacts has prompted the so-called "chlorine-free technology" to grow. When removing chlorine compounds from the bleaching process, it is common to use hydrogen peroxide as an alternative, as hydrogen peroxide is generally believed to be environmentally friendly. Therefore, the use of hydrogen peroxide is increasing and there is a strong incentive to develop more efficient methods for applying hydrogen peroxide to maintain a favorable bleaching economy. Hydrogen peroxide is an oxidizing agent commonly used for imparting gloss to mechanical pulp, semi-mechanical pulp, semi-chemical pulp and recycled pulp. It is also used to aid delignification in chemical pulp bleaching. The Pulp & Paper Research Institute of Canade, PAPRICAN, has developed several new methods of bleaching chemical pulp. Among these, the medium density (10 to 14%) is currently used, but the high temperature peroxide system announced by Liebergo tt et al. Aims to develop the same glossiness as the conventional high density bleaching system. Be interested in. This is accomplished by raising the pulp temperature to about 850 ° C. and lowering the pH, which is unlike conventional high concentration peroxide systems. Since the reaction is faster in this technique, the retention time is shortened from the unit of time to the unit of minute (15 to 30 minutes), and silicate is not required to stabilize the peroxide solution. Peroxide loading is comparable to conventional systems. In the pending application of Bottan, G., a high temperature peroxide system is proposed to operate at 85-95 ° C for a very short time. It has not yet been proposed to heat pulp above 100 ° C. to operate the peroxidation process under pressure for short holding times. To minimize capital expenditure, it is desirable to minimize pulp retention time while maintaining the same degree of gloss that can be achieved with very long retention times. The reuse of residual peroxide by bleaching mechanical pulp has been proposed by Dominiquo Lachenal of the "Ceutre Technique du Papier" in Grenoble, France. This recycles unconsumed (or residual) peroxide (after the first stage reaction tower) by increasing the alkalinity of the pulp suspension. The objective is to remove the expensive dehydration equipment normally used to recover the residual peroxide after the bleaching tower and leave the residual peroxide at the point of fresh peroxide input (usually the mixer before the bleaching tower). Is to recirculate. This proposal is significant when compared to conventional two-stage peroxide bleaching systems that require expensive dewatering equipment between steps. In a conventional reaction column, the first stage reaction is carried out at 60 ° C. for several hours before recycling the residual peroxide. An amount of caustic proportional to the residual peroxide obtained after reaction at 60 ° C. for several hours is added. In chemical pulp, hydrogen peroxide has been used primarily for intermediate concentration systems where the pulp slurry from the previous step is dewatered by thickeners or washers to a concentration of about 10-14%. The peroxide solution is usually charged with alkali in the repulsor (when charged from the thickener or washer) or in the intermediate concentration pump or mixer before the intermediate concentration column. When used as a separate step for chemical pulp bleaching, conventional intermediate-concentration peroxide bleaching steps do not provide a sufficient gloss increase and are said to consume a lot of peroxide, and The consumption of oxides requires extremely long retention times. To make the effect of delignification or gloss more apparent, the peroxide must be applied in several columns. It has been shown that the use of a high concentration peroxidation process operating at concentrations above 25% overcomes many of the limitations of the conventional intermediate concentration peroxidation bleaching process. However, its disadvantages are the need to install a dewatering device that can achieve high input concentrations, more complex operation and more power consumption than intermediate concentration systems. In chemical pulp, the use of peroxide in addition to oxygen to enhance the oxidative extraction stage is widely practiced to reduce the amount of chlorine required in the first stage of pulp bleaching. Conventional Eop (peroxide-enhanced oxidative extraction) uses upflow / downflow columns, requires the use of oxygen gas, and is typically operated in the range 65-85 ° C. It is something. Hydrogen peroxide is also used in the first stage of pulp bleaching to achieve high gloss bleaching stable pulp. It has been believed that hydrogen peroxide decomposes to reduce the effectiveness of bleaching agents, reduce pulp strength, and reduce the economics of bleaching, so it is usually used to bleach pulp at temperatures below 90 ° C. Was limited to. More recently, it has been proposed to use hydrogen peroxide under conditions of high temperatures and relatively long retention times as a means of producing very high gloss pulp used at the end of conventional or chlorine-free bleaching processes. Was done. According to this technique, the required holding time is 1 to 3 hours. Pressurized oxygen peroxide systems with long hold times can raise the upper gloss limit of the pulp beyond that obtained by conventional atmospheric pressure peroxide bleaching processes. It is desirable to minimize the holding time under pressure in order to reduce the capital investment required for equipment. For example, according to the conventional technique, it has been shown by experiments that if it takes about 1 to 3 hours at about 100 ° C., it is very effective in reducing the time required for the peroxide bleaching process. However, the economics of this process do not appear to be very attractive due to the high capital required for the 1-3 hour pressurized peroxidation step. According to the basic information on the economics of the conventional atmospheric pressure peroxide bleaching process and the conventional pressurized oxygen peroxide bleaching process (PO), the investment required for these conventional holding towers is about 850 tons per day. It is calculated as follows for each step: a. Pressurized peroxide tower for 2 hours holding $ 1 million b. Normal stage for holding atmospheric pressure for a long time 1. Hold for 3 hours $ 300,000 2. 6 hours hold $ 400,000 3. 9 hour hold $ 550,000 To achieve the same gloss level in conventional atmospheric pressure peroxide bleaching requires a hold time of more than 6 hours compared to 1 to 3 hours in conventional pressurized oxygen peroxide systems. To do. For example, it may be necessary to provide an atmospheric pressure column with a retention time of 8 to 10 hours to achieve the same results as would fit for a 2 hour pressurized oxygen peroxide system. With just 350 gloss bleaching plants in gloss alone, the need for one peroxide bleaching system for each plant represents an investment of about $ 200-350 million for the industry. To meet increasingly stringent environmental regulations, each plant would need to have more than one peroxide bleaching stage, which would more than double the capital. Thus, a major problem with the prior art is that it requires a very large capital investment to implement the technology. The above describes known limitations in current cellulose and lignin cellulose bleaching processes, and it would be advantageous to provide alternative techniques aimed at overcoming one or more of these limitations. . To this end, a suitable alternative technique having the features described in detail below is provided herein. DISCLOSURE OF THE INVENTION One of the features of the present invention is a step of adjusting the concentration of pulp to 10 to 18%, introducing the pulp into a mixer, and adding sodium hydroxide there to adjust the pH to more than 8.5; Adding 0.5-5.0 wt% hydrogen peroxide; heating pulp above 100 ° C while maintaining sufficient pressure to prevent boiling of pulp liquor; reaction time in column less than 45 minutes Sending pulp through the reactor column at a rate of; cooling the pulp to a temperature below 100 ° C .; keeping the pulp in an atmospheric pressure reaction column, consuming a substantial portion of the residual hydrogen peroxide. Providing a method of bleaching cellulose and lignin cellulosic pulp using hydrogen peroxide comprising the steps of driving the reaction to dryness; and discharging the pulp for further processing. The features of the invention described above, as well as others, will be apparent from consideration of the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows one best mode for carrying out the present invention. FIG. 2 shows another best embodiment of the present invention. FIG. 3 shows a further preferred embodiment of the present invention. FIG. 4 shows a further best embodiment of the present invention. FIG. 5 shows a bleaching stage incorporating yet another best embodiment of the present invention. FIG. 6 shows another best embodiment of the bleaching stage of the present invention applied to an existing bleaching plant. FIG. 7 shows still another preferred embodiment of the bleaching treatment of the present invention in which the residual peroxide is recovered by a conventional washing machine. FIG. 8 shows yet another best mode embodiment of the bleaching process of the present invention in which the residual peroxide is assimilated by pressing. FIG. 9 shows still another preferred embodiment of the bleaching treatment of the present invention in which the residual peroxide is recovered by a press in another method. BEST MODE FOR CARRYING OUT THE INVENTION In FIG. 1, pulp from a conventional washing machine or thickener is introduced into a mixer 100 through a pipe 10, where steam for heating the pulp and pH of the pulp are raised. Alkali is added through pipe 15. The pulp is heated to a pH above 8.5 and preferably adjusted to 9.5-10.5. The heated and pH-adjusted pulp is sent from the mixer 100 through the pipe 20 to the conventional intermediate concentration pump 200 and from there through the pipe 30 to the mixer 300. Hydrogen peroxide solution is added to mixer 300 through pipe 35 in an amount sufficient to provide the required gloss at the end of the reaction. As in conventional peroxide bleaching systems, magnesium compounds for protection of cellulosic viscosity, as well as sequestering agents (SiO 2). ₂ And / or a chelating agent (such as EDTA (ethylenediaminetetraacetic acid) or DTPA (diethylenetriaminepentaacetic acid)) is added to the alkaline solution through pipe 15 and pipe 35, or separately through pipe 16 and Peroxide solution is added through / or 36. According to the present invention, the pulp temperature must exceed 100 ° C, but since the pulp is not normally pumped at this high temperature, the final temperature rise from 85-90 ° C to over 100 ° C is This is done by adding steam between the pump 200 and the mixer 300 through the pipe 37. Pulp heated to the required reaction temperature and adjusted to the required pH is pumped through pipe 40 to an upflow column sized for the holding time required for the reaction. According to the invention, the size of the upflow tube guarantees a pulp holding time of 1 to 30 minutes, preferably 5 to 20 minutes. The pulp is then passed through pipe 50 to a suitable discharge device 500, such as a valve, and from there through pipe 60 for the next wash and bleach step. Since the pulp is bleached above 100 ° C., it is desirable to lower this temperature to prevent pulp flushing, so cooling temperature water or liquid is used for dilution through pipe 70 at the top of the upflow tube. Those skilled in the art will appreciate that the present invention can be implemented in upflow, downflow, upflow / downflow, or other forms, to achieve the required reaction hold time. . Further, those skilled in the art will appreciate that there are additional means of heating and cooling the pulp before and after the reaction, respectively. The detailed description provided herein is not intended to limit the scope of the invention, but is included to elucidate the best mode. FIG. 2 schematically shows another best mode embodiment of the present invention which is the same as that shown in FIG. 1 except that a downflow column 600 is added. According to the invention, the size of the upflow tube guarantees a pulp holding time of 1 to 30 minutes, preferably 5 to 20 minutes. The pulp is then passed through a pipe 50 to a suitable discharge device 500, such as a valve, and from there through a pipe 60 to replace a conventional, preferably existing pulp mill, chlorine-based bleaching process. The leverage is sent to the bleaching tower 600, which can be reused for the new bleaching process. The pulp is kept in this column for an additional 1-5 hours at the required reaction temperature to consume a substantial portion of the hydrogen peroxide applied to the pulp. Since the pulp is bleached above 100 ° C. in column 400, it is desirable to lower this temperature to prevent pulp flushing. In the present invention, the pulp can be cooled before exiting the upflow tube so that the liquid containing the pulp does not flush. This best embodiment is suitable for factories that limit the emission of vapors and residual chemicals to the atmosphere. This is accomplished by adding cooling water or liquid through pipe 70 to dilute the pulp. For example, for pulp treated at a concentration of 12% at 110 ° C. in an upflow column, a liquid at 50-60 ° C. is used for 1.5-2.5 m / ton of pulp. ^Three Cool the pulp to below 100 ° C. by adding. This results in a concentration reduction of about 10%, which does not significantly reduce the performance of the second reaction step. It is particularly desirable to maintain the pulp at the highest temperature allowed under atmospheric pressure. In yet another best mode embodiment of the invention illustrated in FIG. 3, pulp is sent from pipe 60 to column 600 for flushing to atmospheric pressure. The pulp entering the downflow column is at the highest temperature possible, eg 98-100 ° C, which increases the consumption of peroxide in the second reaction stage. Further, the flushed steam is sent to the heat exchanger 700 through the pipe 90. The heat exchanger is used to preheat the wash water applied to the washer prior to the peroxidation process, thereby reducing the amount of steam required for each stage through pipes 15 and 37. Thus, the washing water in the pipe 101 is heated through the pipe 110 before being applied to the conventional washing machine. The best embodiment shown in FIG. 3 is identical to that of FIG. 2 up to the point that pulp is discharged from the upflow reaction column 400. In this case, the pulp retains a substantial amount of residual peroxide upon discharge. The pulp is sent through pipe 50 to a suitable mixing valve 500 where additional alkali is added from pipe 55 to raise the pH of the pulp to above 8.5, preferably from 9.5 to 10.5 for the second reaction step. The pulp cooled by flushing is sent to the conventional down-flow tower 600 through the pipe 60 for the second stage reaction. Conventional downflow towers are of a size that consumes a substantial portion of the residual peroxide and typically hold the pulp for one to five hours. The bleached pulp is sent from tower 600 through pipe 80 to the next process step. The valve 500 has a function of reducing the pressure from the upflow pipe 400 to flush the liquid containing pulp. The alkali is added to the pulp upstream of the valve, and the turbulence generated in the valve serves to mix the alkali and the pulp. It will be appreciated that providing any mixing device at this point in the process will be substantially equivalent to the function of the valve. FIG. 4 shows a further embodiment of the invention which is the same as that of FIG. 3 except for reactivation of the valve by the mixing device 550. In this preferred embodiment of the invention, the size of the upflow tube guarantees a holding time of the pulp of 1 to 30 minutes, preferably 5 to 20 minutes. The pulp is then passed through pipe 50 to a suitable mixing device 550 where residual peroxide is reactivated by alkali added via pipe 55. The pulp is then flushed and the steam thus obtained is directed through pipe 90 to heat exchanger 700 to preheat the water from pipe 101 to a higher temperature. The preheated water is discharged through pipe 110 and used for washing pulp upstream of the bleaching process. FIG. 5 is a schematic diagram of the drifting process according to the present invention. The pulp from the washer or thickener 10 is sent through pipe 11 to a mixer 20, where steam and / or bleaching chemicals sent from pipes 12 and 13 heat the pulp to the required reaction temperature, The pH is raised to the level required for the first reaction with peroxide. The heated and pH-adjusted pulp is sent to the pump 30 through the pipe 21 and further to the mixer 40. Since the pulp is heated above 100 ° C., it is common to apply steam through the pipe 34 and before the mixer for final heating. Alkali, peroxides, chelating agents and other additional agents are added through pipes 32 and 33, mixed homogeneously with the pulp and then passed through pipe 41 to the first peroxide reaction vessel 50. The peroxide reaction vessel 50 is sized to hold for 1 to 30 minutes, preferably 5 to 20 minutes to achieve substantial delignification and / or gloss enhancement. The pulp is then sent through pipe 51 to a discharge device 52. For the best operating costs, washing the pulp after the first peroxide treatment is not essential, but is preferred, and if the washing device is a non-pressurized device, the pulp from the first peroxide reaction vessel It is preferred to cool the pulp before discharge. The cooling diluent can be added into the first peroxidation reaction container 50 through the pipe 53. If the scrubber requires low pulp concentration for proper operation, it is desirable to dilute the pulp before the pump with the filtrate sent through pipe 53. The pulp is washed by the washing machine 60, and the washed pulp is sent to the mixer 70 through the pipe 61. The second step in this best embodiment is an ozone step operated at high or intermediate concentrations, which is 10% to 14% of the conventional washer exit to minimize capital cost of equipment. It is preferably an intermediate concentration step operated at a concentration. As is known in the art, it is necessary to operate below pH 4 to achieve the best results from the ozone process. Thus, before the ozone step, an acid such as sulfuric acid is added to the outlet of the first peroxide reaction vessel 50 through the pipe 53 and shower water is added to the first peroxide washer 60 through the pipe 56. Then, it can be sent through pipe 62 to pump 70, or to another mixer (not shown). The oxidized pulp is sent by pump 70 through pipe 71 to mixer 80 where ozone gas is applied through pipe 72. The pulp is sent to the ozone reaction vessel 90 and held for about 10 minutes or so so that the ozone is almost completely consumed. The pulp exits the ozone reaction vessel and is sent to the wandering device 92 through a pipe 91. The discharge device 92 includes a valve, a plurality of valves, or a mechanical device for reducing the pressure from the ozone reaction container. The pulp is sent through pipe 93 to a gas separator 220, where the gas is separated from the pulp and passed through pipe 202 for processing and / or reuse within the mill. The gas-separated pulp is sent to the pump 210 through the pipe 102. For best operating costs, washing the pulp after the ozone step and before the next bleaching step is not required, but is preferred. If the scrubber requires low pulp concentration for proper operation, it is desirable to dilute the pulp before the pump with the filtrate sent through pipe 103. The pulp is sent to the washing machine 120 through the pipe 104 and is washed with the water or the filtrate sent from the pipe 115. The pulp from the washer 120 is sent through pipe 121 to the mixer 130, where steam and / or bleaching agents are provided from pipes 122, 123 and 124, which require the pulp for the first peroxidation process. Heat to reaction temperature and increase pH to required level. The heated and pH-adjusted pulp is sent to the pump 140 through the pipe 131, and then to the mixer 150 through the pipe 141. Since the pulp is heated above 100 ° C., it is common to apply steam through the pipe 144 and before the mixer for final heating. Alkali, peroxides, chelating agents, and other additional agents are added through pipes 142 and 143, mixed homogeneously with the pulp, and then sent through pipe 151 to a second peroxide reaction vessel 160. The peroxide holding vessel 160 is also sized to have a holding time of 1 to 30 minutes, preferably 5 to 20 minutes to achieve substantial delignification and / or gloss increase, and then It is sent to the discharge device 152 through the pipe 161. It is preferred to wash the pulp after the second peroxide treatment, but this may not be necessary when adding an additional bleaching step that is not significantly affected by the presence of residual peroxide and / or dissolved organics. is there. When the washing device is a non-pressurized device, it is preferable to cool the pulp before discharging from the first peroxidation reaction vessel. Diluting the pulp with the cooling liquid is achieved by sending the cooling liquid from the pipe 153 to the second peroxidation reaction vessel 160. If the scrubber requires a low pulp concentration for proper operation, it is desirable to dilute the pulp before the pump with the filtrate sent through pipe 154. The pulp is then washed by the washer 180 with water or filtrate that is passed through pipe 156. FIG. 6 is a schematic diagram of the bleaching process of the present invention applied to an existing bleaching plant. Typical of many bleaching plants today is DcEoDED. Existing bleaching plants can be retrofitted to incorporate the concepts of the present invention very economically. As shown in the figure, almost all existing equipment is utilized for remodeling, and the investment for that is at most 3 mixers, 3 reaction vessels, 1 ozone generator, and various piping related to remodeling. At times, it may be necessary to make material changes to existing bleaching towers, piping, and other equipment. In the example shown in FIG. 6, the existing chlorination tower is not used for the new bleaching process, but can be used for additional storage or other pre-processing before the new bleaching plant. The existing Eo process is used as a chelating process in which EDTA, DTPA or other chelating agent is added and the pH and temperature are adjusted, preferably pH 5 to 7 and temperature 10 to 60 ° C. The retention time of 30 to 90 minutes normally performed in the conventional Eo process is compatible with this chelating process. After washing with the existing Eo washer, the existing D1 process sends the pulp to a new mixer suitable for the addition of peroxide, adds a suitable reaction vessel, and charges the existing D1 column. It is used as the first peroxide step (P1) by adding or not adding the reactivation of the residual peroxide of the present invention. The first peroxidation step is carried out at a pH of about 8.5 to about 12.5 and a temperature of 100 [deg.] C., preferably 105-120 [deg.] C. for 1 to 30 minutes, preferably 5 to 20 minutes. Driven by time. After washing with the existing D1 washer, the existing E process sends the pulp to a new mixer suitable for ozone addition, adds a suitable reaction vessel and gas separator, and charges the existing E tower. By doing so, it is used as an ozone process. The ozone step is operated at a pH of less than 4, preferably 2 to 4, a temperature of 30 to 70 ° C, preferably less than 50 ° C, a reaction time of less than 10 minutes, preferably less than 5 minutes. After washing with the existing D2 washer, the existing D2 process sends the pulp to a new mixer suitable for peroxide addition, adds a suitable reaction vessel, and charges the existing D2 tower. It is used as the second peroxide step (P2) by adding or not adding the reactivation of the residual peroxide of the present invention. The second peroxidation step is a reaction of the first reaction step with a pH of about 8.5 to about 12.5 and a temperature of more than 100 ° C, preferably 105-120 ° C, for 1-30 minutes, preferably 5-20 minutes. Driven by time. After washing with the existing D2 washer, the pulp is sent to the next post-treatment step, preferably as fully bleached pulp, transferred to a bleached high concentration storage tower. FIG. 7 shows the best practice for reusing the filtrate in the QPZP process. In the present invention, there is a substantial amount of residual peroxide including pulp after the peroxide treatment, and as an example, 2.5% of the pulp is usually added, but the amount of peroxide consumed in the reaction is Less than 1.5% of pulp. Since peroxide is a relatively expensive bleach, it is desirable to recover this residue for reuse in the peroxidation step. This is achieved by recirculating the filtrate from washing after the end of the peroxidation step to a washing step prior to the peroxidation step, as shown. By way of example, a typical filtrate flow is shown in the figure. Here, the concentration at the outlet of each washing machine is 10% and the filtrate stream containing pulp is 9 kg liquid per kg pulp. With a typical dilution factor of 2 in today's bleach plants, the wash water flow to each washer is 11 kg liquid per kg pulp. In the present invention, the filtrate is recycled back through the bleach plant, residual peroxide is applied to the pulp in the washer, and a substantial portion of this residual peroxide is carried over to the peroxide process. Thus, the peroxide application required for this process is reduced by the amount carried over with the pulp. The amount of peroxide carried over is a function of the scrubber discharge ratio (cleaning efficiency). For example, if the washer discharge ratio is 0.85, then about 60% of the residual peroxide is recovered. The same principle applies to the recovery of the alkali used in the peroxidation step. According to this best mode embodiment, the bleaching agent used in the processing step is substantially reduced by the recirculation of the filtrate shown in FIG. 7 compared to other possible circulation modes of the filtrate. FIG. 8 shows another best practice method for reuse of filtrate in QPZP treatment, which is suitable for new bleach plant, ie, if the equipment of existing bleach plant is not reused. There is. FIG. 8 includes the use of a press, preferably a twin roll cleaning press from Ingersoll-Rand Company, instead of a conventional vacuum or pressure washer, or vacuum or pressure diffuser. A typical filtrate stream is shown in the figure, where the outlet concentration of each press is 33.3% and the filtrate stream containing pulp is 2 kg liquid per kg pulp. The wash water flow to each washer with a typical dilution factor of 2 in today's bleach plants is 4 kg liquor per kg pulp. In this case, the filtrate is used for washing by pressing with the same concept as described in FIG. However, in addition to that, the filtrate containing substantially residual peroxide is used in an amount of 7 kg liquor per kg pulp for the dilution of the pulp discharged from the press. The amount of peroxide recovered is similar to that of the vacuum washer described in FIG. The amount of filtrate recovered in the press is a function of the press's discharge ratio (cleaning efficiency). With a press discharge ratio of 0.40, a total recovery of about 60% of residual peroxide is achieved. This is attractive for new installations, as the press requires the same capital as a conventional vacuum or pressure washer, and a further advantage of this configuration is that if the installed cleaning device is a press, the intermediate concentration The ability to incorporate high concentration ozone bleaching rather than ozone bleaching. This option reduces the amount of ozone needed for bleaching and reduces energy requirements in the bleach plant. In FIG. 9, pulp from a conventional washer or thickener is introduced into mixer 100 through pipe 10, where steam to heat the pulp and / or alkali to increase pulp pH is added from pipe 15. The pulp is heated and the pH adjusted to about 11. The heated and pH-adjusted pulp is sent from the mixer 100 through a pipe 20 to a conventional intermediate concentration pump 200, and further from this pump through a pipe 30 to a mixer 300. Hydrogen peroxide solution is added from pipe 35 to mixer 300 in an amount sufficient to maintain a substantial residue at the end of the first reaction step. As is conventional in peroxide bleaching systems, magnesium compounds for the protection of cellulosic viscosity, and sequestering agents (such as silicates) and / or chelating agents (such as EDTA or DTPA) together with an alkaline solution can be piped 15 Added from. The peroxide solution can be applied separately from pipe 35, or from pipes 16 and / or 36. In the present invention, the temperature of the pulp must be above 100 ° C, but pumping the pulp at this high temperature is not practical at this time, so a final temperature rise, for example, from 85-90 ° C to over 100 ° C. The temperature is achieved by adding steam from pipe 37 between pump 200 and mixer 300. The pulp heated to the required reaction temperature and adjusted to the required pH is pumped through the pipe 40 to the upflow pipe 400. The upflow tube 400 is sized for the hold time desired for the first reaction step. In the present invention, the upflow tube is sized to ensure a pulp holding time of 5 to 30 minutes, preferably 5 to 20 minutes. After this hold time, the pulp has retained a substantial residue of peroxide in the pulp slurry. The pulp is sent through pipe 50 to a suitable pressure device 560 where the pulp concentration is increased from about 10% to about 25%. The filtrate is circulated from pipe 55 to pipe 30 to recover the portion of peroxide not consumed in the first reaction step. The pulp is sent from a pipe 60 to a conventional downflow column 600 for a second reaction stage operating at a high consistency (25-30%). Conventional downflow towers are sized to consume a substantial portion of the residual peroxide and typically hold the pulp for 1 to 5 hours. The bleached pulp is sent from tower 600 through pipe 80 to the next process step. For the sake of clarity, the pumps and mixers and the discharge devices and the like shown in FIGS. 1 to 6 are not shown, and the heat exchangers required to maintain the highest temperature in each bleaching step are also the same. . The heat exchanger is installed in the bleach plant according to the correct engineering scheme. Those skilled in the art will appreciate that the present invention may be practiced in upflow, downflow, upflow / downflow, and other forms to achieve the desired retention time for the reaction. Let's do it. Further, those skilled in the art will appreciate that there are additional means of heating and cooling the pulp before and after the reaction, respectively. Further, those skilled in the art will appreciate that the valve used to hold the pressure during the first hold time (upflow pipe) can be provided before or after the mixing device. The details set forth in the present description are not intended to limit the scope of the present invention, but are included solely for purposes of describing the best mode for carrying out the invention. Those skilled in the art will also appreciate that the use of chelating agents and sequestering agents is desirable or required to achieve the benefits of the present invention. The addition of these forms of treatment to the present invention does not limit the scope of the invention. An example is the use of processing steps such as QP, QPQP, QPQZP, QPZQP, PZQP, etc. Furthermore, the person skilled in the art understands that an acid treatment, in particular a treatment to a very low pH, eg below pH 3, can often effectively replace the use of chelating agents in this type of treatment. Will be done. Therefore, addition of an acid step, or replacement of a chelating step with an acid step is also within the scope of the invention. This technology, which has been referred to as the "PAPEROXIDE process", is applied to cellulose or lignin cellulose from softwood, hardwood, as well as chemical pulp, mechanical pulp, semi-chemical pulp, semi-mechanical pulp, or secondary fiber. It can also be applied to various non-wood fibers from pulp. The advantages of such an application are demonstrated by the following examples. The first step of the paper oxide process is to react the pulp with peroxide at an elevated temperature (above 100 ° C) of pH 8.5-12.5 for a limited time of less than about 30 minutes, preferably 5-20 minutes. is there. It is important to carry out this step so as not to cause metal contamination of the pulp slurry. The results of this first step are shown in the following example. Example 1 A sample of a softwood kraft pulp having a kappa number of 27.2 was subjected to oxygen delignification (O step) to give a kappa number of 1. The pulp sample was then processed by a chelation step (step Q) using 0.6% EDTA on the pulp at a hold time of 30 minutes at about 50 ° C. The sample was further subjected to delignification by the conventional hydrogen peroxide step (P) and ozone step (Z) under the conditions and chemical charges shown in Table A, with a Kappa number of 2.0, a gloss of 77.9% ISO and a viscosity of 14.4 mPa. achieved's. The pulp is further treated in a pressurized peroxidation step according to the prior art and compared with the first step of the new process: In all cases, pulp was treated at 10% consistency and held under a pressure of 75 psig with oxygen gas. The following agents were used for bleaching: In the first step of the present invention, the above surprisingly does not impair the viscosity, consumes much less peroxide, and improves the glossiness in a very short time compared to 1 hour or more of the prior art. 85% of that can be achieved. In this example, oxygen gas was used to hold the pulp under pressure, but it is not necessary to expose the pulp to oxygen gas in the first step of the present invention. This is shown in the following example: Example 2 A sample of softwood kraft pulp with a Kappa number of 27.2 was oxygen delignified to a Kappa number of 14. The pulp sample was then processed by a chelation process using 0.6% EDTA on pulp at a hold time of 30 minutes at about 50 ° C. Further, this pulp sample was subjected to delignification by the conventional hydrogen peroxide step and ozone step to achieve a Kappa number of 1.3 and a glossiness of 81.8% ISO. The pulp was further treated with a conventional atmospheric pressure peroxidation step and a conventional pressure peroxidation step and compared with the first step of the present invention as follows: In all cases pulp was treated at 10% consistency and the following agents were used for bleaching: The above shows that the first step of the present invention can achieve results very similar to the techniques of conventional long hold time atmospheric or pressurized oxygen peroxidation steps. Unlike the prior art, these equivalent results can be achieved without the use of oxygen gas in the first step of the invention. In the short time (holding time of 5 minutes) and high temperature first step of the present invention shown in the example, only the vapor pressure of 35 psig of 110 ° C. pulp slurry is compared to the prior art which requires the use of high pressure oxygen gas. It was used. By these examples, according to the present invention, it is possible to achieve results similar to the prior art in a short time and only with the use of high temperature processes, which provides the necessary capital investment for the implementation of the peroxide bleaching technique. Dramatically reduce. The basic principle of the present invention is to carry out the holding in a small reaction column for a relatively short time, that is, at a temperature of about 100-120 ° C. for less than about 30 minutes, after which the pulp is sent to a conventional large holding column, that is, at about 100 ° C. Hold at atmospheric pressure for less than about 1-5 hours to obtain rapid delignification and gloss without washing the pulp between these two steps. Holding for a conventional holding time of 1 to 5 hours results in further consumption of hydrogen peroxide and a further increase in gloss. This allows the inlet pulp to be received with a lower gloss than the pulp in this example. This peroxide process scheme is further improved by combining the principle of short holding times at elevated temperatures with the reactivation of residual peroxide prior to holding in a conventional bleach tower. When carrying out the reactivation of the residual peroxide, the peroxide solution has a significant residual peroxide content after the completion of the first reaction step, which is carried out for a holding time of 1 to 30 minutes, preferably 5 to 20 minutes. More than sufficient to ensure product quality is added, thereby ensuring residual peroxide entering the second reaction step. The bond is described in Bottan's pending order of origin. The present invention is applicable to retrofitting existing bleaching plants and / or constructing new bleaching plants for the production of elemental chlorine-free (ECF) pulp or chlorine-free (TCF) pulp. With or without subsequent retention and with or without reactivation of the residual peroxide, the use of conventional high-temperature peroxide steps with a combination of conventional bleaching chemicals is very economical in a short time. Enables construction of a holding high temperature bleaching plant. For example, by adopting two short-time high temperature peroxidation steps with ozone gas treatment in the middle, from oxygen delignified softwood kraft pulp with an inlet Kappa number of about 14, a high gloss of more than 80% ISO, for example. It is possible to produce a degree of TCF pulp. This bleaching scheme allows for a complete bleaching process with a total holding time in the bleach plant of less than 2 hours. Due to the smaller bleaching reactor compared to conventional bleaching techniques, this method has an unprecedented low capital cost compared to all current TCF pulp production methods. This is demonstrated in the following example: Example 3 A sample of softwood kraft pulp with a Kappa number of 25.7 was oxygen delignified to a Kappa number of 13.6 and a viscosity of 22.4 mPas. This pulp sample was then treated by a chelation process using 0.6% EDTA on the pulp at a holding time of about 50 ° C. for 30 minutes, and then a PZP treatment to bleach the pulp to a gloss above 85% ISO. did. According to the first reaction step of the present invention, a short (5 to 15 minutes), high temperature (107 to 110 ° C.) condition is provided, except that a conventional ozone bleaching step is added between the two peroxidation steps. Was carried out. The gloss of the bleached pulp is 82.3, 87.6 and 91.0 respectively for a total retention time of 10, 20 and 25 minutes in the two peroxide steps. The bleached pulp has a very low kappa number, for example less than 3. Many pulp mills today carry out TCF bleaching of pulp using only peroxide as the active bleaching agent, and these mills produce fully bleached pulps with excessively high Kappa numbers, eg> 5. However, this is not desirable from the perspective of gloss reversion in paper produced from such pulp. The combination of the adoption of the first reaction step of the present invention with the established ozone bleaching technique has substantial advantages over current commercial practice on the quality of paper made from pulp produced by use of this process. The data in Table 5 simulate the present invention using oxygen gas to pressurize the pulp mixture by laboratory bleaching. This is a practical method of simulating bleaching in the laboratory where the pulp temperature is maintained above 100 ° C. However, according to the data in Table 2, this is not envisaged in a commercial implementation to achieve the advantages of the present invention, since the application of oxygen gas is unnecessary in the present invention. The simulation of this process involves an ozone process operating at high concentration, ie about 40% concentration, for laboratory convenience. However, it is recognized that due to the slow ozone input to the pulp, ie less than about 0.6%, one obtains essentially the same results as achieved using ozone at an intermediate concentration, ie about 10-14%. Has been done. Therefore, the present invention is not limited to the use of high-concentration ozone, and in fact it is desirable to use intermediate-concentration ozone in order to utilize the existing equipment in the factory, which is the best practice. Stated. Those skilled in the art will appreciate that the principles of the present invention, namely two peroxidation steps with an acid step in the middle, are also preferred for acids, ie other current or future agents used in media at a pH below about 7. It will be appreciated that it can also be adopted by use. Examples of other intermediate step treatments include, but are not limited to, peracetic acid, caroic acid, treatment with various enzymes, and conjugation of these types of reagents. Furthermore, for certain pulp, it is not necessary to operate both the peroxidation step according to the first step of the present invention, and combine the prior art peroxidation step with one step of the peroxygen bleaching according to the first step of the present invention. , To which one or more intermediate processing steps can be added. The use of more than one peroxidation step with an intermediate step treatment is also considered an effective use of the present invention. Although the examples given here are preferred from an economic standpoint to limit the number of steps in order to minimize the required capital investment, the present invention shows only one or two peroxidation steps. It is not intended to limit the scope. As a further example, the retention of a short, high temperature step of the peroxide bleaching step according to the invention may be carried out in existing bleaching plants, for example using existing extractive hypochlorite or chlorine dichloride bleaching towers. Some modifications reduce the operating costs of the bleaching process as compared to the examples described above, and minimize the amount of equipment added to existing bleaching plants. Example 4 A sample of softwood kraft pulp having a kappa number of 25.7 was oxygen delignified to a kappa number of 13.6. The pulp sample was then treated by a chelation process using 0.6% EDTA on the pulp at a hold time of about 50 ° C. for 30 minutes, and then the P1-Z-P2 treatment bleached the pulp to a gloss above 85% ISO. . According to the present invention, under short (5 to 15 minutes), high temperature (107 to 110 ° C.) conditions, provided that atmospheric pressure holding time is added after each short high temperature peroxidation step, and the two conventional peroxidation steps are performed. The peroxidation step was carried out in combination with the ozone bleaching step of. As shown in Table 6, according to the present invention, by adding atmospheric pressure holding after the short high temperature first step of the present invention, the same amount of peroxide is added to the pulp, and Results similar to those achieved by the prior art with pressure hold for 3 hours are obtained. This is especially preferred because many plants can reuse existing bleaching towers for post process retention and minimize capital investment. As explained above, the investment cost for a container that holds pressure for 1 to 3 hours is relatively high, so even if it is necessary to construct a new atmospheric pressure holding container that holds 1 to 5 hours, this new large pressure container is required. It is envisaged that the short-term (5 to 15 minutes) high temperature holding vessel combined with the atmospheric holding vessel will still be sufficiently attractive in terms of economics compared to the investment requirements of the prior art. In accordance with the present invention, peroxidative bleaching is accomplished by adding an upflow tube for short-term holding (5-20 minutes) in combination with the use of existing bleaching towers that hold an additional 1-4 hours in the bleach plant. Investment per process will be reduced to less than $ 250,000 and total investment in 350 factories in North American industry to less than $ 90 million. This saves $ 130-430 million compared to the prior art. The data provided herein is a numerical representation of the performance of some of the best embodiments and does not limit the scope of the invention. Those skilled in the art will recognize that the present invention can be implemented in numerous ways to achieve its advantages. Some of the above examples have been given to illustrate this point, and these examples do not limit the scope of the invention. The following list shows some of the areas in which the present invention, the "paper oxide" process, can be employed in existing or new bleach plants: Delignification before bleaching plant. 2. Final glossing at the end of the bleach plant. 3. Replacement of existing process of bleach plant. 4. Modifications to improve the performance of existing processes or reduce the use of chlorine compounds in bleaching plants. 5. Pre-treatment before further bleaching step. 6. Performing one or more new or modified steps for any of the above. 7. One or more new steps in combination with one or more intermediate step treatments.

[Procedure amendment] Patent Act Article 184-8 [Submission date] July 1, 1996 [Amendment content] In addition to the mouth, shower-like water is added from the pipe 56 to the first peroxide washer 60. It can then be routed through pipe 62 to pump 70, or to another mixer (not shown). The oxidized pulp is sent by pump 70 through pipe 71 to mixer 80 where ozone gas is applied through pipe 72. The pulp is sent to the ozone reaction vessel 90 and held for about 10 minutes or so so that the ozone is almost completely consumed. The pulp exits the ozone reactor and is sent to the discharge device 92 through the pipe 91. The discharge device 92 includes a valve, a plurality of valves, or a mechanical device for reducing the pressure from the ozone reaction container. The pulp is sent through pipe 93 to a gas separator 220, where the gas is separated from the pulp and passed through pipe 202 for in-plant treatment and / or reuse. The gas-separated pulp is sent to the pump 210 through the pipe 102. For best operating costs, washing the pulp after the ozone step and before the next bleaching step is not required, but is preferred. If the scrubber requires low pulp concentration for proper operation, it is desirable to dilute the pulp before the pump with the filtrate sent through pipe 103. The pulp is sent to the washing machine 120 through the pipe 104 and is washed with the water or the filtrate sent from the pipe 115. The pulp from the washer 120 is sent through pipe 121 to the mixer 130, where steam and / or bleaching agents are provided from pipes 122, 123 and 124, which require the pulp for the first peroxidation process. Heat to reaction temperature and increase pH to required level. The heated and pH-adjusted pulp is sent to the pump 140 through the pipe 131, and then to the mixer 150 through the pipe 141. Since the pulp is heated above 100 ° C., it is common to apply steam through the pipe 144 and before the mixer for final heating. Alkali, peroxides, chelating agents, and other additional agents are added through pipes 142 and 143, mixed homogeneously with the pulp, and then sent through pipe 151 to a second peroxide reaction vessel 160. The peroxide holding vessel 160 is also sized to have a holding time of 1 to 30 minutes, preferably 5 to 20 minutes to achieve substantial delignification and / or gloss increase, and then It is sent to the discharge device 152 through the pipe 161. It is preferred to wash the pulp after the second peroxide treatment, as this will remove residual peroxide. In all cases pulp was treated at 10% consistency and the following agents were used for bleaching: The above shows that the first step of the present invention can achieve results very similar to the techniques of conventional long hold time atmospheric or pressurized oxygen peroxidation steps. Unlike the prior art, these equivalent results can be achieved without the use of oxygen gas in the first step of the invention. In the short time (holding time of 5 minutes) and high temperature first step of the present invention shown in the example, only the vapor pressure of 35 psig of 110 ° C. pulp slurry is compared to the prior art which requires the use of high pressure oxygen gas. It was used. By means of these examples, according to the invention, it is possible to achieve a result similar to the prior art only by using a high-temperature process in a short time, which is stated in the best mode. Those skilled in the art will appreciate that the principles of the present invention, namely two peroxidation steps with an acid step in the middle, are also preferred for acids, ie other current or future agents used in media at a pH below about 7. It will be appreciated that it can also be adopted by use. Examples of other intermediate step treatments include, but are not limited to, peracetic acid, caroic acid, treatment with various enzymes, and conjugation of these types of reagents. Furthermore, for certain pulp, it is not necessary to operate both the peroxidation step according to the first step of the present invention, and combine the prior art peroxidation step with one step of the peroxygen bleaching according to the first step of the present invention. , To which one or more intermediate processing steps can be added. The use of more than one peroxidation step with an intermediate step treatment is also considered an effective use of the present invention. Although the examples given here are preferred from an economic standpoint to limit the number of steps in order to minimize the required capital investment, the present invention shows only one or two peroxidation steps. It is not intended to limit the scope. As a further example, a short, high temperature step of the peroxidative bleaching step according to the present invention may be followed by a hold of an existing bleaching plant, for example using an existing extracted hypochlorite or chlorine dichloride bleaching tower. The modifications will reduce the operating costs of the bleaching process compared to the example above and minimize the equipment added to the existing bleach plant. The data provided herein is a numerical representation of the performance of some of the best embodiments and does not limit the scope of the invention. Those skilled in the art will recognize that the present invention can be implemented in numerous ways to achieve its advantages. The above several examples are provided to illustrate this point. Adjust the pulp concentration to 8-18%; add alkali to bring the pulp above pH 9.5; add hydrogen peroxide to produce residual peroxide after passing through the first reactor column; pulp liquor Heating the pulp to a temperature above 100 ° C., maintaining sufficient pressure to prevent boiling of the pulp in the reactor column at a rate that provides a reaction time of less than 45 minutes in the reactor column. Cooling the pulp to a temperature of less than 100 ° C .; adding an alkali to bring the pulp to pH 9.0 or above; keeping the pulp in the reaction column under atmospheric pressure to remove residual hydrogen peroxide. Wood pulp and other cellulose with hydrogen peroxide, characterized in that the reaction is allowed to proceed for 1-5 hours until part is consumed; and the pulp is discharged for further processing; Ligni Method for bleaching cellulose-based fibrous material. 2. The bleaching method according to claim 1, wherein sufficient alkali is added to bring the pulp to a pH of 9.5 to 11.5, including the first alkali addition step. 3. The bleaching method according to claim 1, wherein the pulp is passed through the reactor column at a rate that gives a reaction time of 5 to 20 minutes in the reactor column. 4. Adding hydrogen peroxide to produce residual peroxide after passing through the first reactor column comprises adding 0.5% to 5% hydrogen peroxide by absolute dry weight of the pulp; The bleaching method according to claim 1, characterized in that 5. The bleaching method according to claim 4, wherein the residual hydrogen peroxide is reactivated by adding sufficient alkali to bring the pulp to pH 9.5 or more. 6. Comprising exposing the pulp to a first stage hydrogen peroxide bleaching treatment; the first stage treatment: adjusting the pulp concentration to 8% -18%; the pH of the pulp to at least 9.5, Also, an alkali and hydrogen peroxide are added to make the hydrogen peroxide content 0.5 to 5.0% by dry weight of the pulp; while maintaining a sufficient pressure to prevent boiling of the pulp liquid, the pulp is heated to 100 ° C. Heating to above temperature; and passing the pulp through the reactor column at a rate that gives a reaction time of less than 45 minutes in the reactor column; cooling the pulp and sending the cooled pulp to a washer Where the unconsumed bleach and a substantial portion of the dissolved material are removed from the pulp and, if necessary, the pulp concentration is adjusted to a value suitable for the second stage bleaching process. Two-step bleaching The second step of bleaching is: adding sufficient acid or alkali to adjust the pH of the pulp to a value suitable for the bleaching agent; mixing the pulp with the second bleaching agent and the pulp Introduced into a mixer; the pulp is sent from the mixer to a reaction vessel, where the pulp is held for a time sufficient to consume a substantial portion of the applied agent; the pulp is sent from the reaction vessel to a washer where it is not consumed Bleaching agent and dissolved organic material are removed from the pulp, and if necessary, the pulp concentration is adjusted to 8-18%: consisting of: a step; and exposing the pulp to a third-stage bleaching step. The third stage treatment comprises the same steps as described for the first stage hydrogen peroxide bleaching treatment following the adjustment of pulp concentration; cellulose and ligninse characterized in that Three-stage bleaching process of loin material. 7. In the second stage bleaching process, sufficient acid is added to adjust the pH of the pulp to a value of less than 4, and the step of introducing the pulp into the mixer is a suitable transport to mix with the pulp. Adding ozone gas into the gas; and sending the pulp from the mixer to an ozone reactor where the pulp is held for less than 10 minutes to consume substantially all of the ozone; and Delivered from the ozone reactor to a washer where a substantial portion of unconsumed bleach and dissolved organic material was removed from the pulp and, if necessary, pulp concentration adjusted to 8-18% for the third stage treatment. The bleaching method according to claim 6, characterized in that 8. The bleaching method according to claim 7, wherein the amount of ozone used is 0.1 to 2.0 absolute dry weight% of the pulp. 9. The bleaching method according to claim 7, wherein the ozone bleaching step is performed at a concentration of 8 to 18%. Ten. The bleaching method according to claim 9, wherein the amount of ozone applied is 0.2 to 1.0% by dry weight of pulp. 11. The bleaching method according to claim 7, wherein at least two stages of ozone treatment do not perform interstage pulp washing. 12． The bleaching method according to claim 7, wherein an additional bleaching step is performed between the first peroxide treatment and the second peroxide treatment. 13. The inflow pulp is adjusted to a concentration of more than 20%; the discharged pulp is dewatered to a concentration of more than 20% and the filtrate from the dehydration process following the bleaching step is used to dilute the inflow pulp. The bleaching method according to claim 7, characterized in that a substantial part of the residual hydrogen peroxide is recovered. 14. 14. The pulp according to claim 13, wherein the pulp discharged from the reaction stage is retained in the reaction column and the reaction is promoted for 30 minutes to 3 hours until a substantial part of the residual peroxide is consumed. Bleaching method. 15. 15. The bleaching method according to claim 14, wherein an alkali is added to activate residual hydrogen peroxide before the pulp is retained in the reaction tower. 16． The bleaching method according to claim 14, wherein the pulp is cooled before being held in the reaction tower. [Figure 3] FIG. 4

────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Miller, William Jay             New Hampshire, USA             03104, Manchester, Poplast             REIT, 168 (72) Inventor Roy, Brian Pee             Quebec H9J 1 in Canada             Zet 3, Pierre Fon, Meloche,             17594 (72) Inventor Van Leelop, Barbara             Quebec, H9C, 1C, Canada             Yeah 7, Il Bizar, Avenue             Riviera, 856-4s (72) Inventor Berry, Richard M             Quebec City Canada 7 Canada 7 Canada             Rour 5, Il Perot, Dessertable,             478

Claims (1)

[Claims] 1. Adjust the pulp concentration to 8-18%;     Adding alkali to bring the pulp to a pH above 8.5;     Adding hydrogen peroxide corresponding to at least 0.5 absolute dry weight% of the pulp;     While maintaining sufficient pressure to prevent boiling of the pulp liquor, Heating to a temperature above 00 ° C;     Reacting the pulp in a reactor column at a rate that gives a reaction time of less than 45 minutes. Pass through the column;     Cooling the pulp to a temperature below 100 ° C .;     The pulp is kept in the reaction tower under atmospheric pressure so that a substantial part of the residual hydrogen peroxide is consumed. Promote reaction for 1-5 hours until paid; and     Discharging the pulp for further processing;   Hydrogen peroxide, which is characterized by the following steps: A method of bleaching lulose and lignin cellulose fibrous material (pulp). 2. It should be noted that sufficient alkali is added to bring the pulp to a pH above 9.5. The method according to claim 1, which is regarded as a characteristic. 3. Sufficient alkali is added to bring the pulp to pH 9.5-11.5 The method according to claim 1, wherein: 4. Before the pulp gives a reaction time of 5 to 20 minutes in the reactor column The method according to claim 1, wherein the reactor column is passed through the reactor column. Method. 5. Adjust the pulp concentration to 10-18%;     Adding alkali to bring the pulp to a pH above 8.5;     Add hydrogen peroxide so that there is residual peroxide after passing through the first reactor column;     While maintaining sufficient pressure to prevent boiling of the pulp liquor, Heating to a temperature above 00 ° C;     Reacting the pulp in a reactor column at a rate that gives a reaction time of less than 45 minutes. Pass through the column;     Adding alkali to bring the pulp to a pH above 9.0;     The pulp is kept in the reaction tower under atmospheric pressure so that a substantial part of the residual hydrogen peroxide is consumed. Promote reaction for 1-5 hours until paid; and     Discharging the pulp for further processing;   Cellulose and ligninse using hydrogen peroxide characterized by the following steps: A method of bleaching lulose material (pulp). 6. Characterized by adding sufficient hydrogen peroxide corresponding to 0.5 to 5.0% by weight The method according to claim 5. 7. Sufficient alkali is added to the residual hydrogen peroxide to bring the pH of the pulp above 9.5. Claim 6 characterized in that it is reactivated by being obtained. Method. 8. Adjust the pulp concentration to 8-18%;     Adding alkali to bring the pulp to a pH above 8.5;     Hydrogen peroxide corresponding to 0.5 to 5.0 absolute dry weight% of the pulp is added;     While maintaining sufficient pressure to prevent boiling of the pulp liquor, Heating to a temperature above 00 ° C;     Reacting the pulp in a reactor column at a rate that gives a reaction time of less than 45 minutes. Pass through the column;     Cooling the pulp to a temperature below 100 ° C .; and     Discharging the pulp for further processing;   Cellulose and ligninse using hydrogen peroxide characterized by the following steps: A method of bleaching lulose material (pulp). 9. Exposing the pulp to a first stage hydrogen peroxide bleaching treatment;     The first stage process is:       Adjusting the concentration of the pulp to 8% -18%; In addition, in order to adjust the content of hydrogen peroxide to 0.5 to 5.0% by dry weight of the pulp, Add Lucari and hydrogen peroxide; maintain sufficient pressure to prevent boiling of the pulp liquor. The pulp is heated to a temperature above 100 ° C. while being held; and 45 in the reactor column. Passing the pulp through a reactor column at a rate to provide a reaction time of less than minutes; Cool the pulp and wash the cooled pulp Sent to the pulp where a substantial portion of unconsumed bleach and dissolved material is removed from the pulp. And, if necessary, the pulp bleaching is adjusted to a value suitable for the second stage bleaching treatment. Consisting of steps;     Exposing the pulp to said second stage bleaching;     The second stage bleaching is:       Sufficient acid or alkali to adjust pulp pH to a value suitable for bleach Introducing the pulp into a mixer that mixes the pulp with a second bleaching agent; The lup is sent from the mixer to a reaction vessel where the pulp is a substantial portion of the applied drug. The pulp is held for a sufficient time to be consumed; the pulp is sent from the reaction vessel to a washer. Where unconsumed bleach and dissolved organic material have been removed from the pulp and must be If necessary, the pulp concentration is adjusted to 8-18%: consists of steps;     And having the step of exposing the pulp to a third stage bleaching treatment;     The third stage treatment is the hydrogen peroxide of the first stage following the adjustment of pulp concentration. Comprising the same steps as described for the bleaching treatment;   3 stages of cellulose and lignin cellulosic material (pulp) characterized by Bleaching method. Ten. To adjust the pH of pulp to a value less than 4 in the second stage bleaching process Sufficient acid is added to the pulp, and the pulp is mixed with ozone gas in a suitable carrier gas and the pulp. The pulp is introduced into a mixer that mixes the pulp; Here, the pulp is kept for 10 minutes or less so that substantially all of ozone is consumed. And the pulp is sent from the ozone reactor to a washer where unbleached bleaching occurs. The agent and a substantial portion of the dissolved organic material are removed from the pulp and, if necessary, pulsed. Concentration is adjusted to 8-18% for the third stage treatment;   The method according to claim 9, characterized in that 11. The amount of ozone applied is 0.1-2.0% by dry weight of pulp, characterized by The method according to claim 10, wherein 12. The ozone bleaching step is carried out at a concentration of 8-18%. 10. The method according to 10. 13. Characterized in that the amount of ozone applied is 0.2-1.0% by dry weight of pulp 13. The method according to claim 12, wherein: 14. A contract characterized in that two or more stages of ozone treatment do not perform interstage pulp washing. The method described in Scope 9 of the application. 15． An additional bleaching step is performed between the first and second peroxide treatments The method according to claim 9, characterized in that 16. Concentrated pulp adjusted to over 20%; discharged pulp over 20% Is dewatered into the pulp and the filtrate from the dehydration process following the bleaching stage is diluted to dilute the pulp. Characterized in that a substantial portion of the residual hydrogen peroxide is recovered. The method according to claim 9, wherein 17． The pulp discharged from the reaction stage is retained in the reaction tower, and a substantial part of residual peroxide is Claims characterized in that the reaction is promoted for 30 minutes to 3 hours until the minutes are consumed. The method described in box 16. 18． Before the pulp is retained in the reactor, it is activated to activate residual hydrogen peroxide. 18. The method according to claim 17, characterized in that Lucari is added. 19. The pulp is cooled before being retained in the reaction tower. The method described in range 17.