Method and installation for waste paper recycling

FIELD: fabrics, paper.

SUBSTANCE: invention is related to pulp and paper industry. Waste paper recycling into finished paper mass is carried out in several stages of process. For extent of whiteness specified value is set for finished mass, besides extent of whiteness is measured between stages of process. Efficiency of process stage is identified with account of occurring expenses relative to increase of whiteness extent, and in system of process control dynamic tuning of separate process stages is performed with account of overall efficiency, in particular efficiency of overall expenses of process. Parametres of quality, such as extent of whiteness, are actually registered and assessed. Quality development and costs modeling is carried out in separate stages of process, and also dynamic continuous adjustment of data in separate stages of process.

EFFECT: improved efficiency of waste paper recycling and control of waste paper quality.

15 cl, 4 dwg

 

The invention relates to a method for processing waste paper in the finished pulp in several stages of the process, and at least one quality parameter sets the specified value for the finished weight, and before and/or after at least two stages of the process are determined by measuring a value of at least one quality parameter. The invention relates also to an appropriate facility for recycling.

Waste in many countries is an important raw material for paper and cardboard industry. Also in the paper industry are constantly growing as the quality requirements of the product, and the pressure on costs. For use of waste paper as raw material, in particular, for a higher grade of paper for graphic works are decisive material composition, purity grade and degree of contamination. The process of recycling is complicated by the increasing share of foreign paper components, as adhesives, plastic film, metal clips, textiles, synthetic materials that are not recyclable recyclable paper and cardboard, etc. part of the paper is affected, for example, seasonal variations in the consumption of paper, the differences between the various local systems of collection and sorting./p>

Routine laboratory measurements documented in real time fluctuations in the quality of the waste paper until ready supply and deliver important information regarding the status of the installation for processing waste paper. Installation for processing waste paper works, usually in several stages of the process. Routine laboratory measurements require time-consuming and, in particular, are therefore only partly suitable for regulating the recycling of waste paper and the relevant stages of the process. Therefore, quality fluctuations can react only with a delay and a relatively coarse steps.

DE 19653479 C1 describes a method for conducting a process for the bleaching of fibrous materials. Using the state model and the process model for optimization of the bleaching process. According to DE 19653479 C1 taking measurements obtained from the fibrous suspension test sheet or fibrous suspension which help develop the above model.

Basic problems of quality control in the processing of waste paper as the mutual dependence of the individual process steps, such as bleaching and flotation, and large time lag at the present time are not solved or resolved at least unsatisfactory.

The objective of the invention I have is providing opportunities for improved recycling of waste paper, and, in particular, take into account the problems described above and the increased requirements in the paper industry, mentioned in the introduction.

This task is solved by the method according to paragraph 1 of the claims, and the effectiveness of the process for the improvement of at least one quality parameter is determined in this stage of the process and with the process control system to produce a dynamic adjustment of the separate stages of the process with regard to the overall efficiency of the process. The problem is solved by using the installation according to paragraph 14 of the claims.

A preferred form of the further development of the invention are specified in dependent claims.

According to the invention be made available to higher quality management for recycling, which is advantageous, in particular, for devices with varying quality paper. According to the invention is specific to the product and/or customer job quality for the finished mass is achieved with very little cost. According to the invention in the optimum are no longer just the individual stages of the process, but an optimum from the point of view of the cost of setting up a separate stages of the process. When connect the individual partial optimization of the process and set up a separate stages of the process is t load of waste paper to a finished weight optimal time and cost moreover, take into account quickly and efficiently quality fluctuations in the paper.

Mainly the configuration of the individual steps of the process performed by step-by-step approval process. Thus by successive approximation to the optimal cost development of the quality parameter reaches the optimal setup with a relatively low cost.

Mainly the configuration of the individual steps of the process performed by the prediction control model. This improves the stability and regulation.

Mainly the installation of the set values in the framework of predictive control model produced for stage process using measurements of this stage of the process. Thus, it can quickly especially to take into account fluctuations in the process, in particular, those that are explained by the change in the quality of paper.

Preferably the setting of the set values is produced for stage process using at least one model for stage process. This provides a small time delay regulation.

Preferably at least one model will adapt. This leads to the further improvement of the control accuracy.

Mainly in the model postpone the effectiveness of the process in the form of cost-effectiveness. The sama is provided, that can optimize the ratio costs/benefits not only the individual stages of the process, but also for the overall process with a low response time for changes in the process.

It is advisable that the regulation of the quality of the process produced by the assigned stage of the process module control. Thus, controlling the way the times of passage in the process to calculate the time for the required actions.

Mainly the regulatory model works with the prediction model. Based on the data and analytical knowledge in such a regulatory model implicitly deferred optimal operation stage of the process.

It is advisable to use as parameters the quality of whiteness and/or filler content. Whiteness is arguably the most important optical characteristics of paper. The content of the filler may be significant, for example, to characterize the suitability of the paper for printing and also affects the degree of whiteness.

Mainly determine the value of at least one quality parameter produced by the at least one programmable sensing element. A similar approach can be especially effective to control the development of the quality parameter during stages% of the SAR.

Mainly determine the value of at least one quality parameter is carried out online. Thus values provide rapid and the reaction rate regulation is significantly increased.

For effective bleaching of waste paper is an advantage if one or more of the process steps executed in the form of flotation or bleaching. In the processing of waste paper, for example, after the first of the so-called preliminary flotation can be followed by bleaching, which adjoins precista flotation, after which again should bleaching.

The efficiency of the process executed in the form of bleaching, especially preferably can be defined as improvement of at least one quality parameter in the bleaching to energy use and/or dosing of chemicals in bleaching. This is a particularly robust approach to assess the effectiveness of bleaching.

Mainly efficiency made in the form of flotation step of the process is determined depending on the improve at least one aspect of quality in flotation, and depending on the operation mode, chemistry discoloration and/or loss of solids in the flotation. This approach provides a reliable assessment of the effectiveness of flotation.

Mainly at least one dimension DL of the measurement values of at least one quality parameter is located before the first stage of the process, made in the form of flotation. If the value of the quality parameter for the first time identify possible early after grinding, at the latest, however, before the first stage of flotation, this value is at least approximately representative for the quality of the paper before loading.

Mainly a device for implementing the process contains basic automation and at least one superimposed on the basic automation assigned to the process module of the regulation, which among other things sets the set value and controls the times of passage on the stage of the process.

Further details and advantages of the invention are explained in further detail and with examples of how to perform in connection with the drawings which show:

Figure 1 - stages of the process and the selected measurement,

Figure 2 - example of the development of the quality parameter in the processing of waste paper,

Figure 3 - schematic representation of the regulation of sequential approximation to the optimal from a cost perspective to the development of the quality parameter,

4 is a schematic representation of the regulation approach forecasting model.

Figure 1 shows the many stages P1 - P4 recycling, as well as many measuring points M1 - M4, which are located between the stages of the process is as P1 - P4 or after the process steps P1 - P4. In the measurement M1 - M4 of measure for actual reception quality parameters is carried out online.

The individual process steps P1 - P4 are assigned modules regulation R1 - R4.

In the following only as an example, assume that the process P1 is executed in the form of pre-flotation step of the process P2 in the form of a dispersion-bleaching, the process P3 in the form of a cleaner cell flotation and process P4 in the form of a dispersion-bleaching.

As quality parameters QP (see also Figure 4), for example, determine the degree of whiteness produced quantity, the content of filler or other parameters that are essential for the quality of the paper. The quality parameter QP can be determined, for example, on paper, on the suspension of waste paper, fibrous material or, respectively, in the finished material.

At the measuring point M0, which is located between a rough sorting and preliminary flotation, register, for example, whiteness is not yet bleached fibrous material. Programmable sensor element degree of whiteness compensates for the magnitude of the impact on the density of the material, the content of small fibers and filler, and can thereby give the degree of whiteness is not yet discolored trial sheet. The measuring point M1, which arrangement is between about pre-flotation and dispersion make-bleaching can be subdivided more finely on the measurement MA in acceptance of the preliminary flotation and measurement M1b after thickening. Here with the help of sensitive elements determine the degree of whiteness of the test sheet. Between the stage of the process P2, and process P3, that is, preferably after oxidative dispersion-bleaching, is located next measuring point M2, preferably in the inlet line cleaner cell flotation. Similarly, the measurement MA and M1b sensitive elements in the measurement MA and M3b or, respectively, in place of measurement M3 determine the degree of whiteness of the material after the cleaner cell flotation. Place of measurement M4, for example, normalizing Converter in bleaching the pipe determines the degree of whiteness of the bleached finished material.

The regulation module R1 or R3 stage flotation is preferably from model-based block direct connection to negotiate the degree of reflection characteristics of the fibrous suspension. In the supported data model process of flotation, which is based on data and analytical knowledge, implicitly deferred optimal mode of operation for flotation. In block feedback module regulation R1 or R3 forecast is compared with the actually achieved whiteness. For this comparison should model, since not all values of pressure are known and thereby limit as missing input data of the model accuracy is prognozirovaniya.

Special issue dispersion-bleaching, in the example, the process P2 and P4 are high processing times, which depend in particular, depending on the actual degree of loading of the installation. This limits here the dynamics of the actuator feedback so that a model-based block direct communication module regulation of R2 or R4 dispersion-bleaching have to manage the process over a much longer time than in the flotation without a backward message block feedback. It is possible to compensate, at least partially using an independent model lag.

Figure 2 shows an example of the development of the quality parameter QP in the paper recycling. Specifically presents a typical development degree of whiteness in the installation of recycling. Whiteness is perhaps the most important optical characteristics of the paper and thus a particularly important quality parameter QP. The degree of whiteness is determined preferably in the form of a corresponding international standard ISO extent of white in the blue region of the spectrum at the Central wavelength of 457 nm.

The degree of whiteness of the bleached finished material is achieved through the removal of printing inks and bleaching fibrous material. Figure 2 shows the development corridor degree of whiteness according to the process steps P1 - P4, in the example, it will prefix the other flotation, dispersion make-bleaching, precista flotation and the final dispersion make with the subsequent bleaching in terms of recovery. At each stage of the process P2 - P4 is based on the result of one or more previous stages P1 - P3. So the appearance gray fibrous material in the dispersant depends on the energy input and associated with etem shift the distribution of values of the particles of printing inks. The modified particle spectrum of printing inks and added chemicals bleaching in turn affect the efficiency of the cleaner cell flotation. However, the bleaching stages also depends on the fiber material and its history. In the drawing whiteness indicated, as usual, in percent.

Removal of printing inks in the process P1 and P3, i.e. flotation, is affected primarily by the mode of operation, the chemistry of bleaching and loss of solids. The dispersion make-bleaching, that is, the process P2 and P4, and the first dispersion make-bleaching, the process P2, contains preferably the peroxide bleaching, the second dispersion make-bleaching, the process P4, contains preferably dithionite bleaching, influenced, in part, by input of energy and dosing of chemicals. A particularly important factor in the process of recycling are the costs of different modes to operate the range.

Figure 3 shows schematically the regulation consistent approximation to the optimal cost development of the quality parameter QP, that is, the degree of whiteness. Thus to determine the changes of the values of the quality parameter QP in a separate process steps P1 - P4 as changes in quality of d1- d4. In module efficiency stages K1 - K4 determine the cost efficiency in the process and pass on to the module efficiency of the process L. Block set the value S specifies the setpoint for at least one quality parameter QP at the end of the process of recycling waste paper. This prescribed set value also serves on the module efficiency of the process L. With module efficiency of the process L and module efficiency stages K1 - K4 change incrementally job for changes in quality in the individual process steps P1 - P4 in the direction of lower costs, that is, in particular, in lower total costs, while optimally setup. This ensures compliance with task unit set the value of s is Shown in figure 3 regulation does not depend on the process model, since the fluctuations in the composition of the fibrous material and change the status of the installation are recorded directly in the process steps P1 - P4 and their effectiveness satr is so

Figure 4 shows schematically the regulation with the predictive approach model. Regulation comes from neobespechenija fibrous material, for which you define a value for the quality parameter QP in place measure M0. First, in the first operation determines advantageous from the point of view of cost separation changes in the quality of d1- d4for example, an increase in the degree of whiteness by all of the following process steps P1 - P4. This occurs preferably in the module correction of the set value KM1. Set the value of Δ1- Δ4for process steps P1 - P4 issued from module correction of the set value KM1 module set the value of KV1. To determine the best from the point of view of cost separation changes in the quality of d1- d4on the stage of the process P1 - P4 postpone cost-effectiveness in at least one of a cost model. Preferably the cost model delay for each stage of the process P1 - P4.

In the module, the correction of the setpoint KM2 produce a new calculation advantageous from the point of view of cost-sharing changes the quality of the d1- d4for process P2 - P4, the following stage of the process P1. In this new calculation includes the results of the process P1. So for fibrous material, which is pre-flotation, on the basis of re is of Ulatov flotation calculate the new set of values.

Thus the ability of bleaching fibrous material and the status of the installation are included in the regulation quality. Appropriate correction of the set value Δ2' - Δ4' lay in the module, set the value KV2. Correction of the set value Δ2' - Δ4' used to adjust the settings specified value Δ2- Δ4.

In order correction module setpoint KMZ are the results of the process P2, the first dispersion-bleaching to determine targets for subsequent phases of the process P3 - P4. Similarly lay and apply the correction of the set value Δ3" - Δ4" in the module, set the value of KV3. Finally, in order correction module setpoint KM4 are also the results of the process P3 to calculate the correction of the set value Δ4"'.

Prediction regulation model works dynamically. A significant advantage lies in the high speed and stability at the expense of model-based block direct communication. Thus it is possible to optimally use the potential of fibrous material and process steps P1 - P4. Quality fluctuations are also included in management as a modified situation costs. Provided by the model adaptation And to accompany applied to define which of the given values for the model, which are preferably implemented in modules correction of the set value KM1 - KM4. To improve the applied models can along with due to the operation of the oscillation install the pilot starts purposefully to change modes of operation, to lay in the database models a comprehensive display. By successive settings of the process steps P1 - P4 each other, it becomes possible cost effective mode of recycling.

Underlying the teachings of the invention can be summarized as follows.

The invention relates to a method and installation for processing waste paper in the finished material in several stages of the process, and degree of whiteness establish the value specified for the finished material, and measure the degree of whiteness between the process steps P1 - P4. According to the invention the efficiency of the process define the emerging costs relative to the increase of the degree of whiteness and in the process control system to produce a dynamic adjustment of the separate stages of the process with regard to the overall efficiency, in particular, the cost-effectiveness of the process. The quality parameters as the degree of whiteness of the relevant register and evaluate. Produce a simulation of the development of quality and cost in a separate process steps P1 - P4, as well as dynamic, after ovately configuration data in a separate process steps P1 - P4. The overall efficiency of the recycling thus considerably increased.

Previously known methods for processing waste paper do not exhaust the potential of the plant and fibrous material because, in the previously known methods are not evaluated quantitatively mutual dependence of the process steps P1 to P4. According to the invention not only provide stable operation of the installation, but you can also consider short-term changes in the composition of the fibrous material and content of the printing inks. According to the invention dynamically coordinate individual process steps P1 - P4, and take into account the overall efficiency of the recycling process. Essential to this are the costs of various modes of operation. Count the cost of raw materials - waste paper, the costs of chemicals, energy and waste management. Evaluation of quality parameters produced depending on the installation status and targets for the finished material. On the basis of the degree of whiteness and the content of the filler, as well as the workload of the installation and the associated times of passage downloadable parties optimally configure on each other separate stages of the process. Corresponding to the invention, the configuration process occurs during the current process is continuous, relevant and in-line.

1. The way the La recycling in the finished pulp in several stages of the process (P1; P2; P3; P4), and installed setpoint for at least one quality parameter (QP) for ready mass at the end of the process, with the following method:
a) determining changes in the value of the quality parameter (QP) in a separate process (P1; P2; P3; P4);
b) determining the effectiveness of individual stages of the process (P1; P2; P3; P4) relative changes in the values of the quality parameter (QP) in the respective stages of the process (P1; P2; P3; P4); and
c) step-by-step approval process (P1; P2; P3; P4) relative changes in the values of the quality parameter (QP) in the respective stages of the process (P1; P2; P3; P4) based on the efficiency of the individual steps of the process, to achieve optimized overall efficiency of the recycling process, and as quality parameters (QP) used the degree of whiteness produced the number or content of the filler, and one or more stages of the process (P1; P2; P3; P4) are in the form of flotation and/or bleaching, the bleaching efficiency is defined as the ratio of the change quality parameter (QP) in the bleaching to the input of energy and/or the dosing of chemicals in bleaching, and flotation effectiveness is defined as the ratio of the change of the quality parameter (QP) in the flotation mode of operation, the chemistry of bleaching and/or loss of solids.

2. The method according to claim 1, inwhich the efficiency of the process (P1; P2; P3; P4) lay in the model in the form of cost-effectiveness.

3. The method according to claim 1, in which the change of the quality parameter (QP) in the process (P1; P2; P3; P4) produced by the assigned stage of the process (P1; P2; P3; P4) module control (R1; R2; R3; R4).

4. The method according to claim 3, in which the module regulation (R1; R2; R3; R4) works with the prediction of the model.

5. The method according to any one of claims 1 to 4, in which at least one measuring point to determine the value of the quality parameter (QP) is located before the first made in the form of flotation stage of the process.

6. Method for processing waste paper in the finished pulp in several stages of the process (P1; P2; P3; P4), and installed setpoint for at least one quality parameter (QP) for ready mass at the end of the process, with the following method:
a) determination of the division of changes in the value of the quality parameter (QP) in a separate process (P1; P2; P3; P4) based on computed using the model overall efficiency of the recycling process;
b) select setting set values for the individual stages of the process (P1; P2; P3; P4) relative changes in the values of the quality parameter (QP) on the basis of the specific separation of changes in the value of the quality parameter (QP) in a separate process (P1; P2; P3; P4); and in the relevant stages of the process is (P1; P2; P3; P4); and
c) sequential selection of new installations specified values for the following after the first stage of the process (P1) for further stages of the process (P2; P3; P4), and determine the actual value changes of the quality parameter (QP), respectively, of the preceding stage of the process, and it is accordingly introduced into the subsequent determination of the division of changes in the value of the quality parameter (QP) respectively in the following stages of the process and a further selection of units specified values, respectively, for the following stages of the process, and as quality parameters (QP) used the degree of whiteness produced the number or content of the filler, and one or more stages process (P1; P2; P3; P4) are in the form of flotation and/or bleaching, the bleaching efficiency is defined as the ratio of the change of the quality parameter (QP) in the bleaching to the input of energy and/or the dosing of chemicals in bleaching, and flotation effectiveness is defined as the ratio of the change of the quality parameter (QP) in the flotation mode of operation, the chemistry of bleaching and/or loss of solids.

7. The method according to claim 6, in which the installation of the set values for stage process (P1; P2; P3; P4) is determined using measurements before this stage of the process (P1; P2; P3; P4).

8. The method according to claim 7, in which set the specified values for stage process (P1; P2; P3; P4) is determined using at least one model for stage process (P1; P2; P3; P4).

9. The method according to claim 8, in which adapting at least one model.

10. The method according to claim 6, in which the efficiency of the process (P1; P2; P3; P4) lay in the model in the form of cost-effectiveness.

11. The method according to claim 6, in which the change of the quality parameter (QP) in the process (P1; P2; P3; P4) produced by the assigned stage of the process (P1; P2; P3; P4) module control (R1; R2; R3; R4).

12. The method according to claim 11, in which the module regulation (R1; R2; R3; R4) works with the prediction of the model.

13. The method according to any of PP-12, in which at least one measuring point to determine the value of the quality parameter (QP) is located before the first made in the form of flotation stage of the process.

14. Installation for implementing the method according to any one of the preceding paragraphs with multiple devices for each relevant stage of the process (P1; P2; P3; P4), with many measuring devices (M1; M2; M3; M4) to determine the value of the quality parameter (QP), and the measuring device (M1; M2; M3; M4) is located at the input, output, before and/or after the device for phase process (P1; P2; P3; P4), with the unit set the value (S) for the specified job values for the quality parameter (QP) for ready mass in the rates of recycling process, and with the process control system (R) for dynamic adjustment of the individual stages of the process (P1; P2; P3; P4), taking into account the efficiency of the individual steps of the process (P1; P2; P3; P4) and the overall efficiency of the recycling process and quality parameters (QP) are the degree of whiteness produced quantity or filler content.

15. Installation 14, in which the device for phase process (P1; P2; P3; P4) contains basic automation and at least one superimposed on the basic automation module regulation (R1; R2; R3; R4).



 

Same patents:

FIELD: process engineering.

SUBSTANCE: invention relates to techniques designed to determine and control inorganic and organic deposits in aqueous system, preferably, in circulating water systems incorporated with paper or cardboard production machines. Proposed method consists in placing one or more specimens into aqueous system and, preset time interval of exposure expired, removing it therefrom. Then specimens are prepared for surface analysis. Deposits formed on specimens are determined by microscopy, and/or gas/chromatography, and/or mass spectroscopy. Note here that spesimen(s) is (are) placed in additives containers, water spraying locations or an all damp places or those with higher moisture content.

EFFECT: higher validity of tested system state data.

6 cl, 23 dwg, 5 ex

FIELD: measuring equipment.

SUBSTANCE: speed of absorption is determined on basis of alternation in time of coefficient of luminescence brightness of oil patch, irradiated by ultraviolet radiation.

EFFECT: higher quality, higher precision.

1 cl

The invention relates to a device for determining the quality of the fiber suspensions as recycled waste paper, and primary - cellulose and can be used in the pulp and paper and other industries that use water suspension of fibers

The invention relates to the field of long-term storage of documents and can be used to control biological status of documents in the process of long-term storage, preventive conservation and restoration of inspections and surveys in libraries, archives, museums, private collections

The invention relates to the design, control and test devices used in the pulp and paper industry

The invention relates to methods for determining the toxicity of insoluble materials and can be used in paper, printing, food processing and water toxicology

The invention relates to the pulp and paper industry and can be used under laboratory conditions to determine the orientation of the fibers in the paper

FIELD: textile fabrics, paper.

SUBSTANCE: method is related to bleaching of hardwood sulphate pulp and may be used in pulp and paper industry for production of fibrous semi-finished products for production of printing types of paper. Suggested method is realised in the following manner. Unbleached hardwood sulphate pulp is disintegrated in water, then squeezed, placed into bleaching bath and delignificated by sodium hypochlorite with its consumption of 3% (in units of active chlorine) from mass of absolutely dry fiber. Then cellulose mass is flushed by water. Then double-stage bleaching of cellulose is carried out by sodium chlorite in acid medium with intermediate alkaline extraction. At the first stage of bleaching sodium chlorite consumption makes 1.5-2.5% (in units of active chlorine), and at the second stage of bleaching it makes 0.4-0.5% (in units of active chlorine) from mass of absolutely dry cellulose. After the first stage of bleaching by sodium chlorite mass is flushed by water and exposed either to oxidising alkaline treatment in the presence of hydrogen peroxide at its expenditure of 0.5%, expenditure of sodium hydroxide of 2.0% from mass of absolutely dry fiber, or alkaline treatment with hydrogen peroxide at its expenditure of 1.0%, expenditure of sodium hydroxide of 0.5%, sodium silicate - 3.0% from mass of absolutely dry fiber. After alkaline extraction cellulose is flushed, and the second stage of bleaching by sodium chlorite is carried out. Afterwards mass is flushed with water, and its acid treatment is carried out with hydrochloric acid.

EFFECT: improved quality of bleached cellulose, enhanced efficiency of process and ecological safety.

1 tbl, 6 ex

FIELD: textile fabrics, paper.

SUBSTANCE: invention is intended for application in pulp and paper industry. Method of bleaching process control for waste paper treatment is characterised by the following operations: preparation of fibrous suspension; measurement of fibrous suspension whiteness; mixing of fibrous suspension with bleaching substance; supply of mixed fibrous suspension to reservoir for bleaching; extraction of mixed fibrous suspension from reservoir for bleaching after certain time interval. Bleaching substance comprises mixture of separate substances, besides amount and/or composition of added bleaching substance is established depending on measured whiteness of fibrous suspension so that possible permanent specified whiteness of extracted fibrous suspension is achieved. Whiteness of extracted fibrous suspension is measured and compared in adaptation mode with specified whiteness, and depending on result of comparison compliance pattern is coordinated. Bleaching device contains reservoir for bleaching, supply pipeline with whiteness sensitive element, metering device, control device, discharge device.

EFFECT: prevention of large oscillations of fibrous suspension whiteness at the end of bleaching process, at that load of used bleaching substance is minimum.

7 cl, 2 dwg

FIELD: paper; chemistry.

SUBSTANCE: method of cellulose fiber modification is realised in the following manner. Suspension mass of cellulose fibers is prepared. In process of its bleaching cellulose derivative is added in at least one stage of acid bleaching. pH of suspension mass is in the interval from approximately 1 to approximately 4, and temperature - in interval from approximately 30 to approximately 95°C. As cellulose derivative carboxy-alkyl-cellulose is used, for instance, carboxy-methyl-cellulose. From this suspension of bleached fiber mass paper is produced by means of dehydration of this suspension on the mesh with formation of paper.

EFFECT: higher strength in wet condition and softness of paper.

42 cl, 2 dwg, 1 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: cellulose delignification process comprises alkali treatment, delignification with hydrogen peroxide with sodium hydroxide and sodium silicate additive, and acid treatment. Alkali treatment consumes 0.5% hydrogen peroxide and 2.0% sodium hydroxide based on the weight of absolutely dry cellulose and is conducted for 2.0-2.5 h at 60-90°C. Acid treatment of delignified product is accomplished with aqueous hydrochloric acid, which is consumed in amount 1.0% based on the weight of absolutely dry fibers, while treatment is conducted for 30-60 min at ambient temperature.

EFFECT: enhanced economical efficiency without loss cellulose characteristics.

2 tbl, 11 ex

FIELD: pulp-and-paper industry.

SUBSTANCE: unbleached sulfate cellulose obtained from hardwood is subjected oxygen-alkali delignification, after which treated with chlorine dioxide in presence of oxyethylidenediphosphonic acid and then consecutively hydrogen peroxide and chlorine dioxide solutions. Process may be used in production of bleached fibrous intermediates.

EFFECT: increased whiteness and strength characteristics of cellulose and improved environmental safety of bleaching process.

2 cl, 1 tbl

FIELD: pulp-and-paper industry, in particular method for pulp whitening.

SUBSTANCE: pulp mass with concentration of 5-10 % after oxygen-alkaline treatment in step I is treated with sulfuric acid in consumption of 5 % based on dry cellulose mass and pH 2.6-3.0. In step II peroxide treatment is carried out in alkali consumption of 1.0-1.3 % based on dry cellulose mass, and in step III pulp is treated with chlorine dioxide in consumption of 1.0-1.6 % based on dry cellulose mass at 70°C.

EFFECT: pulp with increased whiteness.

1 tbl, 17 ex

FIELD: pulp-and-paper industry, in particular method for PULP whitening.

SUBSTANCE: craft pulp mass with concentration of 2.5-5.0 % after oxygen-alkaline treatment is treated with potassium permanganate in consumption of 0.01-0.1 % based on dry cellulose at 40-80°C and pH 1.6-3.0 or with sulfuric acid solution in consumption of 1.0-1.5 % at 90°C for 30 min. In steps II and IV cellulose with concentration of 10 % is treated with hydrogen peroxide in consumption of 2 % based on mass of dry cellulose for 120 min at 80-90°C and pH 9.5-10.5 wherein consumption of sodium alkali and sodium silicate is 1.3 % and 2.5 %, respectively. In step III cellulose is treated with potassium permanganate in consumption of 0.01-0.4 % under step I conditions.

EFFECT: reduced consumption of whitening agents.

1 tbl, 9 ex

FIELD: cellulose production.

SUBSTANCE: invention relates to manufacture of cellulose from cotton lint after alkali pulping or from prehydrolyzed wood cellulose and can be utilized in paper-and-pulp industry or in manufacture of artificial fibers, films, and other cellulose materials. Pulped cotton lint or prehydrolyzed wood cellulose is bleached by sodium hypochlorite at modulus 1:20 to 1:30 and 20-30°C, washed, treated for 50-60 min with 1.0-1.5% sodium hydroxide solution at 80-90°C, and subjected to souring, after which desired product is recovered. More specifically, cotton lint after alkali pulping is bleached in two steps separated by washing. In the first step, bleaching is carried out for 0.5-2.0 h at active chlorine concentration 0.3-2.0 g/L and, in the seconds step, for 0.5-6.0 h with 1.0-6.0 g/L active chlorine concentration. Prehydrolyzed wood cellulose is leached in one step for 0.5-6.0 h with 0.3-6.0 g/L active chlorine concentration.

EFFECT: improved quality of product, reduced average degree of polymerization, and increased reactivity thereof.

2 tbl, 18 ex

The invention relates to the production of cellulose and can be used to produce bleached pulp without using chlorine-containing reagents

The invention relates to biotechnology; multicomponent system for mediated mediated enzymatic oxidation includes (a) an oxidation catalyst chosen from the group margantsovistyh oxidase, (b) an oxidizing agent chosen from the group comprising oxygen and oxygen-containing compounds, b) the mediator from the group of compounds containing Mn ions

FIELD: cellulose production.

SUBSTANCE: invention relates to manufacture of cellulose from cotton lint after alkali pulping or from prehydrolyzed wood cellulose and can be utilized in paper-and-pulp industry or in manufacture of artificial fibers, films, and other cellulose materials. Pulped cotton lint or prehydrolyzed wood cellulose is bleached by sodium hypochlorite at modulus 1:20 to 1:30 and 20-30°C, washed, treated for 50-60 min with 1.0-1.5% sodium hydroxide solution at 80-90°C, and subjected to souring, after which desired product is recovered. More specifically, cotton lint after alkali pulping is bleached in two steps separated by washing. In the first step, bleaching is carried out for 0.5-2.0 h at active chlorine concentration 0.3-2.0 g/L and, in the seconds step, for 0.5-6.0 h with 1.0-6.0 g/L active chlorine concentration. Prehydrolyzed wood cellulose is leached in one step for 0.5-6.0 h with 0.3-6.0 g/L active chlorine concentration.

EFFECT: improved quality of product, reduced average degree of polymerization, and increased reactivity thereof.

2 tbl, 18 ex

FIELD: pulp-and-paper industry, in particular method for PULP whitening.

SUBSTANCE: craft pulp mass with concentration of 2.5-5.0 % after oxygen-alkaline treatment is treated with potassium permanganate in consumption of 0.01-0.1 % based on dry cellulose at 40-80°C and pH 1.6-3.0 or with sulfuric acid solution in consumption of 1.0-1.5 % at 90°C for 30 min. In steps II and IV cellulose with concentration of 10 % is treated with hydrogen peroxide in consumption of 2 % based on mass of dry cellulose for 120 min at 80-90°C and pH 9.5-10.5 wherein consumption of sodium alkali and sodium silicate is 1.3 % and 2.5 %, respectively. In step III cellulose is treated with potassium permanganate in consumption of 0.01-0.4 % under step I conditions.

EFFECT: reduced consumption of whitening agents.

1 tbl, 9 ex

FIELD: pulp-and-paper industry, in particular method for pulp whitening.

SUBSTANCE: pulp mass with concentration of 5-10 % after oxygen-alkaline treatment in step I is treated with sulfuric acid in consumption of 5 % based on dry cellulose mass and pH 2.6-3.0. In step II peroxide treatment is carried out in alkali consumption of 1.0-1.3 % based on dry cellulose mass, and in step III pulp is treated with chlorine dioxide in consumption of 1.0-1.6 % based on dry cellulose mass at 70°C.

EFFECT: pulp with increased whiteness.

1 tbl, 17 ex

Up!