Integrated treatment method and application of pulp and papermaking wastewater

Abstract

The application discloses a pulping and papermaking wastewater integrated treatment method and application and belongs to the technical field of pulping and papermaking wastewater treatment. The pulping and papermaking wastewater integrated treatment method comprises the following steps: pumping pulping and papermaking wastewater to be treated into a multistage anaerobic reactor, and adding a composite microbial agent into the multistage anaerobic reactor; the adding amount of the composite microbial agent is 0.1wt%-5wt% of the pulping and papermaking wastewater to be treated, the fermentation temperature is 28-35 DEG C, the fermentation time is 4-50h, the produced biogas enters a gas collecting chamber, sludge is concentrated to a sludge collecting area through natural sedimentation, and clear water is collected to a water outlet tank and discharged through a water outlet and a drainage tank. By adding an appropriate amount of the composite microbial agent and adjusting the number of stages of the multistage anaerobic reactor according to water quantity and pollution load, the cellulose, hemicellulose, sulfate radical and COD in the effluent are significantly reduced, the pH value of the inlet water does not need to be strictly controlled, the treatment effect is stable, the efficiency is high, the treatment cost is low and the management and operation are simple.

Description

TECHNICAL FIELD

[0001] The application relates to a pulping and papermaking wastewater integrated treatment method and application and belongs to the technical field of pulping and papermaking wastewater treatment. BACKGROUND

[0002] In recent years, with the gradual implementation of the national environmental protection policy, the investment and construction of the wastewater treatment system of industrial enterprises are gradually strengthened. The use cost of industrial water is increasing year by year, and the wastewater discharge requirements are also constantly improved and strict.

[0003] The pollutants and total concentration of the wastewater generated in the recycling process of waste paper are higher and higher, and the pollutant composition contained in the pulping and papermaking wastewater tends to be complex. High sulfur, high salt, cellulose and hemicellulose, high pollution load and complex pollution composition become the characteristics of this part of wastewater. The existing anaerobic technology is very difficult to degrade cellulose and hemicellulose in the wastewater, so this part of wastewater is a kind of industrial wastewater with relatively high treatment difficulty.

[0004] If the water inlet index of the existing anaerobic reactor is not controlled well, serious scaling and clogging will occur in the anaerobic reactor, which will cause the anaerobic system to be unable to operate normally and seriously affect the normal production of the enterprise. The common upflow anaerobic tower requires that the SS of the anaerobic water inlet is not higher than 500 mg / L, and the pH value of the water inlet needs to be strictly controlled. However, due to the reduction of water consumption in the production process, the COD load of the wastewater of the pulping and papermaking industry, especially the wastewater of the waste paper pulping and papermaking industry, is as high as 10,000 mg / L and above. The general treatment method has limited COD removal rate, and it is also difficult to reduce the SS of the wastewater to below 800 mg / L. SUMMARY

[0005] In order to solve the above problems, a pulping and papermaking wastewater integrated treatment method and application are provided. By adding an appropriate amount of composite bacterial agent and adjusting the number of stages of the multi-stage anaerobic reactor according to the water quantity and pollution load, the cellulose, hemicellulose, sulfate and COD of the effluent are significantly reduced. At the same time, the pH value of the water inlet does not need to be strictly controlled. The treatment effect is stable, the efficiency is high, the treatment cost is low, and the management and operation are simple.

[0006] The technical scheme of the application is as follows:

[0007] A pulping and papermaking wastewater integrated treatment method, comprising the following steps:

[0008] The pulping and papermaking wastewater to be treated is pumped into a multi-stage anaerobic reactor, and a composite bacterial agent is added thereto. The addition amount of the composite bacterial agent is 0.1wt%-5wt% of the pulping and papermaking wastewater to be treated, the fermentation temperature is 28-35 DEG C, the fermentation time is 4-50h, the produced biogas enters the gas collection chamber, the sludge is concentrated in the sludge collection area by natural sedimentation, and the clear water is collected in the effluent tank and discharged through the effluent outlet and the drainage tank.

[0009] In order to meet the wastewater treatment effect, the number of stages of the multi-stage anaerobic reactor can be selected according to the water quantity and pollution load; the multi-stage anaerobic reactor in the present application is a 2-6 stage anaerobic reactor.

[0010] Optionally, the complex bacterial agent comprises Lactobacillus fermentum and Arcobacter ellisii.

[0011] Optionally, the volume ratio of the Lactobacillus fermentum to Arcobacter ellisii is 1:(0.3-2).

[0012] Optionally, the preparation method of the complex bacterial agent specifically comprises the following steps:

[0013] (1) inoculate Lactobacillus fermentum bacterial liquid and Arcobacter ellisii bacterial liquid into reinforced Clostridium medium (RCM), and incubate at 28-32°C for 5-7d, so that the medium becomes turbid; then transfer it to anaerobic reinforced Clostridium medium, and incubate at 28-32°C for 22-26h, so that the medium becomes turbid, and obtain bacterial liquid;

[0014] (2) filter the pulp and papermaking wastewater after flocculation and sedimentation, adjust the pH of the wastewater to 7.0-9.0, and add nutrients to prepare wastewater medium;

[0015] (3) inoculate the bacterial liquid obtained in step (1) into the wastewater medium, and obtain multiple single bacterial liquids after separate culture and separate expansion culture, and mix the multiple single bacterial liquids to obtain seed bacterial liquid;

[0016] (4) supplement 10-20% of auxiliary growth microorganisms to the seed bacterial liquid to obtain mixed bacterial liquid, and domesticate the strains in the mixed bacterial liquid to obtain the complex bacterial agent.

[0017] Optionally, the reinforced Clostridium medium comprises 10g / L of proteose peptone, 10g / L of beef powder, 3g / L of yeast powder, 5g / L of glucose, 1g / L of soluble starch, 5g / L of sodium chloride, 3g / L of sodium acetate, 0.5g / L of L-cysteine salt, 0.5g / L of agar, and has a pH value of 6.8±0.1.

[0018] Optionally, the auxiliary growth microorganism is Bifidobacterium (ATCC29521), which is purchased from Guangdong Microbial Culture Collection Center.

[0019] Optionally, in step (3), the bacterial solution obtained in step (1) is inoculated into the wastewater culture medium at a volume ratio of 40%-60%, and then incubated at a constant temperature of 28-32°C for 36-60h; then the bacterial solution after the incubation is inoculated into the wastewater culture medium at a volume ratio of 1%-2%, and then incubated at a constant temperature of 28-32°C for 36-60h to obtain a plurality of single bacterial solutions.

[0020] Optionally, in step (4), the specific steps of the domestication cultivation are as follows: the mixed bacterial solution and the wastewater culture medium are mixed at a volume ratio of 1:(2-5), and then incubated at a constant temperature of 28-32°C for 36-60h to obtain the composite microbial agent.

[0021] Optionally, the wastewater culture medium is prepared by adjusting the pH of the to-be-treated pulp and papermaking wastewater to 6.8-7.5 by sodium hydroxide or hydrochloric acid, and then sterilizing at 110-120°C for 15-30min.

[0022] Optionally, the concentration of cellulose / hemicellulose in the to-be-treated pulp and papermaking wastewater is 500-4000mg / L.

[0023] The concentration of sulfate in the to-be-treated pulp and papermaking wastewater is 1000mg / L.

[0024] Optionally, the concentration of COD in the to-be-treated pulp and papermaking wastewater is 10000-30000mg / L.

[0025] Optionally, the method further comprises a step of pretreating the to-be-treated pulp and papermaking wastewater.

[0026] The pulp and papermaking wastewater first passes through a grid and an inclined screen in sequence, and then enters a coagulation reaction tank, where polyaluminum chloride and polyacrylamide are added, and then the mixture is stirred uniformly and enters a sedimentation tank for sludge-water separation, and the effluent is the to-be-treated pulp and papermaking wastewater.

[0027] Optionally, the mass ratio of polyaluminum chloride to polyacrylamide is 1:(0.001-0.01), and the total amount of polyaluminum chloride and polyacrylamide added is 0.01wt%-0.5wt% of the pulp and papermaking wastewater.

[0028] According to another aspect of the present application, the application provides a use of the pulp and papermaking wastewater integrated treatment method as described in any one of the above aspects in treating wastewater containing cellulose, hemicellulose and sulfate.

[0029] In the present application, the sludge is flocculent sludge, which is derived from one or more than two of the sludge produced by a municipal sewage aerobic treatment system, the sludge produced by a paper mill sewage aerobic treatment system, and the sludge produced by a pulp and papermaking wastewater anaerobic treatment system constructed by Shandong Huanfa.

[0030] The beneficial effects of the present application include but are not limited to:

[0031] 1. The pulp and papermaking wastewater integrated treatment method of the present application has a multi-stage anaerobic reactor, which provides the growth environment required by different types of microorganisms, not only balances the nutrients required for the growth of complex microorganisms, but also fully considers the growth habits of different microorganisms, and ensures that they are fully fermented in the anaerobic environment.

[0032] 2. The pulp and papermaking wastewater integrated treatment method of the present application, Lactobacillus fermentum is mainly used to degrade cellulose, hemicellulose, miscellaneous cells, starch and viscose substances in wastewater, Arcobacter ellisii is mainly used to reduce the concentration of sulfate and nitrate in wastewater, and reduce the biological toxicity of sulfate in wastewater to Lactobacillus fermentum and other anaerobic sludge; the synergistic effect of Lactobacillus fermentum and Arcobacter ellisii is more conducive to the degradation of pollutants in wastewater.

[0033] 3. The pulp and papermaking wastewater integrated treatment method of the present application does not need to strictly control the pH value of the influent, does not need to set a hydrolysis acidification section before anaerobic, and the effluent of the sedimentation tank directly enters the multi-stage anaerobic reactor, which simplifies the treatment process, reduces the project land occupation, while ensuring the treatment effect and reducing the labor cost.

[0034] 4. The pulp and papermaking wastewater integrated treatment method of the present application only needs simple flocculation and sedimentation, without introducing too many chemical agents, avoiding secondary pollution of wastewater, and reducing the cost of reagents; the grid can remove larger impurities in wastewater, and the inclined screen is used to recover fibers in wastewater, ensuring the treatment effect of pulp and papermaking wastewater. DETAILED DESCRIPTION

[0035] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The endpoints of the ranges and any values are understood to be approximate values. The endpoints of the ranges of values and the values of individual points are not to be construed as limiting the range of values between the endpoints. The disclosure contemplates the inclusion of other ranges between the recited ranges.

[0036] Unless otherwise indicated, conventional methods or those described in the literature were used. Unless otherwise indicated, the materials used were commercially available from the manufacturers (reagents, chemicals, and the like) commonly used in chemical syntheses.

[0037] In the present application, the preservation number of Lactobacillus fermentum is CGMCC No. 24291, and the preservation number of Arcobacter ellisii is CGMCC No. 24261. Both Lactobacillus fermentum and Arcobacter ellisii are from Shandong Huanfa Science and Technology Development Co., Ltd. and are preserved in China General Microbiological Culture Collection Center.

[0038] Example 1

[0039] A pulp and papermaking wastewater integrated treatment method, comprising the following steps:

[0040] The pulp and papermaking wastewater first passes through a grid and an inclined screen in sequence, and then enters a coagulation reaction tank, polyaluminum chloride and polyacrylamide with a mass ratio of 1:0.005 are added, wherein the total amount of polyaluminum chloride and polyacrylamide added is 0.08wt% of the pulp and papermaking wastewater, and after uniform stirring, it enters a sedimentation tank for sludge-water separation, and the effluent is the pulp and papermaking wastewater to be treated;

[0041] The pulp and papermaking wastewater to be treated is pumped into a three-stage anaerobic reactor, and a composite microbial agent is added thereto, the addition amount of the composite microbial agent is 0.5wt% of the pulp and papermaking wastewater to be treated, the fermentation temperature is 30℃, the fermentation time is 28h, the produced biogas enters a gas collection chamber, the sludge is concentrated to a sludge collection area by natural sedimentation, and the clear water is collected to an effluent tank and discharged through an effluent outlet and a drain tank;

[0042] The preparation method of the composite microbial agent specifically comprises the following steps:

[0043] (1) Lactobacillus fermentum bacterial liquid and Arcobacter ellisii bacterial liquid with a volume ratio of 1:1 are inoculated in a reinforced Clostridium culture medium, and incubated at 30℃ for 6d, and the turbidity of the culture medium can be observed; then it is transferred to an anaerobic reinforced Clostridium culture medium, and incubated at 30℃ for 24h, and the turbidity of the culture medium changes, and the bacterial liquid is obtained;

[0044] (2) The pulp and papermaking wastewater is filtered after flocculation and sedimentation, the pH of the wastewater is adjusted to 7, and nutrient substances are added to prepare a wastewater culture medium;

[0045] (3) The bacterial liquid obtained in step (1) is inoculated in the wastewater culture medium at a volume ratio of 50%, and incubated at 30℃ under constant temperature conditions for 48h; then the bacterial liquid after single culture is inoculated in the wastewater culture medium at a volume ratio of 1.5%, and incubated at 30℃ under constant temperature conditions for 48h to obtain multiple single bacterial liquids, and the multiple single bacterial liquids are mixed to obtain a seed bacterial liquid;

[0046] (4) Adding the diluted pulping and papermaking wastewater to the seed bacterial solution, mixing the bacterial solution and the wastewater culture medium at a volume ratio of 1:5, and culturing at 30°C for 48h to obtain a composite bacterial agent;

[0047] (5) The anaerobic system is first added with flocculent anaerobic sludge, and then added with the composite bacterial agent at a ratio of 1:0.05.

[0048] Example 2

[0049] A pulping and papermaking wastewater integrated treatment method, comprising the following steps:

[0050] The pulping and papermaking wastewater first passes through a grid and an inclined screen in sequence, and then enters a coagulation reaction tank, where polyaluminum chloride and polyacrylamide are added at a mass ratio of 1:0.001, and the total amount of polyaluminum chloride and polyacrylamide is 0.2wt% of the pulping and papermaking wastewater, and after uniform stirring, it enters a sedimentation tank for mud-water separation, and the effluent is the pulping and papermaking wastewater to be treated;

[0051] The pulping and papermaking wastewater to be treated is pumped into a three-stage anaerobic reactor, and a composite bacterial agent is added thereto, and the addition amount of the composite bacterial agent is 0.35wt% of the pulping and papermaking wastewater to be treated, the fermentation temperature is 28°C, and the fermentation time is 50h, the produced biogas enters a gas collection chamber, the sludge is concentrated in a sludge collection area by natural sedimentation, and the clear water is collected in an effluent tank and discharged through an effluent outlet and a drain tank;

[0052] The preparation method of the composite bacterial agent specifically comprises the following steps:

[0053] (1) Lactobacillus fermentum bacterial solution and Arcobacter ellisii bacterial solution at a volume ratio of 1:0.3 are inoculated into a reinforced Clostridium culture medium, and cultured at 28°C for 7d, and the culture medium becomes turbid, then it is transferred to an anaerobic reinforced Clostridium culture medium, and cultured at 28°C for 26h, and the culture medium becomes turbid, and a bacterial solution is obtained;

[0054] (2) The pulping and papermaking wastewater is filtered after flocculation and sedimentation, the pH of the wastewater is adjusted to 7.0, and nutrient substances are added to prepare a wastewater culture medium;

[0055] (3) The bacterial solution obtained in step (1) is inoculated into the wastewater culture medium at a volume ratio of 40%, and cultured at 28°C for 60h; then the cultured bacterial solution is inoculated into the wastewater culture medium at a volume ratio of 1%, and cultured at 28°C for 60h to obtain multiple single bacterial solutions, and the multiple single bacterial solutions are mixed to obtain a seed bacterial solution;

[0056] (4) Add 10% by volume of Bifidobacterium (ATCC29521) and anaerobic flocculent sludge to the seed culture to obtain a mixed culture. Mix the mixed culture with the wastewater culture medium at a volume ratio of 1:5 and incubate at 28℃ for 60 hours to obtain a compound bacterial agent.

[0057] (5) First, add flocculent anaerobic sludge to the anaerobic system, then add compound microbial agent at a ratio of 1:0.03.

[0058] Example 3

[0059] An integrated treatment method for pulp and paper wastewater includes the following steps:

[0060] The pulp and paper wastewater first passes through a screen and an inclined screen, then enters a coagulation reaction tank. Polyaluminum chloride and polyacrylamide are added at a mass ratio of 1:0.01, with the total amount of polyaluminum chloride and polyacrylamide added being 0.5 wt% of the pulp and paper wastewater. After being stirred evenly, the wastewater enters a sedimentation tank for mud-water separation. The effluent is the pulp and paper wastewater to be treated.

[0061] The pulp and paper wastewater to be treated is pumped into a three-stage anaerobic reactor, and a compound microbial agent is added to it. The amount of compound microbial agent added is 0.1 wt% of the pulp and paper wastewater to be treated. The fermentation temperature is 35℃ and the fermentation time is 8 hours. The biogas produced enters the gas collection chamber, the sludge is collected in the sludge collection area by natural sedimentation, and the clean water is collected in the effluent trough and discharged through the effluent outlet and drainage trough.

[0062] The preparation method of the compound microbial agent specifically includes the following steps:

[0063] (1) Inoculate Lactobacillus fermentum and Arcobacterellisii bacterial suspensions at a volume ratio of 1:2 into Clostridium perfringens medium and incubate at 32℃ for 5 days. The medium will become turbid. Then transfer it to anaerobic Clostridium perfringens medium and incubate at 32℃ for 22 hours. The medium will become turbid, and the bacterial suspension will be obtained.

[0064] (2) Take pulp and paper wastewater, flocculate and precipitate it, filter it, adjust the pH of the wastewater to 8.0, and add nutrients to make wastewater culture medium.

[0065] (3) The bacterial solution obtained in step (1) was inoculated into the wastewater culture medium at a volume ratio of 60% and cultured separately at a constant temperature of 32℃ for 36h; then the bacterial solution cultured separately was inoculated into the wastewater culture medium at a volume ratio of 2% and cultured separately at a constant temperature of 32℃ for 36h to obtain multiple single bacterial solutions, and the multiple single bacterial solutions were mixed to obtain seed bacterial solution.

[0066] (4) The seed bacterial solution was supplemented with 20% by volume of Bifidobacterium (ATCC29521) and anaerobic flocculent sludge to obtain a mixed bacterial solution. The mixed bacterial solution and the wastewater medium were mixed at a volume ratio of 1:4 and incubated at 32°C for 36h to obtain a composite microbial agent.

[0067] (5) The anaerobic system was first supplemented with flocculent anaerobic sludge, and then with the composite microbial agent at a ratio of 1:0.01.

[0068] Comparative Example 1

[0069] Anaerobic flocculent sludge was used, and the difference from Example 1 was that the composite microbial agent was replaced with Lactobacillus fermentum.

[0070] Comparative Example 2

[0071] Anaerobic flocculent sludge was used, and the difference from Example 1 was that the composite microbial agent was replaced with Arcobacter ellisii.

[0072] Comparative Example 3

[0073] Anaerobic flocculent sludge was used, and the difference from Example 1 was that the volume ratio of Lactobacillus fermentum to Arcobacter ellisii was 1:0.1.

[0074] Comparative Example 4

[0075] Anaerobic flocculent sludge was used, and the difference from Example 1 was that the composite microbial agent was added at a dosage of 5wt% of the pulp and papermaking wastewater to be treated, the fermentation temperature was 25°C, and the fermentation time was 5h.

[0076] Comparative Example 5

[0077] Anaerobic flocculent sludge was used, and the difference from Example 1 was that the composite microbial agent was not added to the 3-stage anaerobic reactor.

[0078] Comparative Example 6

[0079] Anaerobic granular sludge was used, and the difference from Example 1 was that the sludge was conventional anaerobic granular sludge.

[0080] Test Example

[0081] The treatment methods in Examples 1-3 and Comparative Examples 1-6 were respectively subjected to effect tests.

[0082] The concentration of cellulose and hemicellulose in the pulp and papermaking wastewater to be treated was 1200 mg / L, the concentration of sulfate in the pulp and papermaking wastewater to be treated was 1000 mg / L, and the concentration of COD in the pulp and papermaking wastewater to be treated was 15000 mg / L. The test was performed according to the methods of Examples 1-3 and Comparative Examples 1-6, respectively. The test data are shown in Table 1.

[0083] Table 1

[0084]

[0085] As shown in Table 1, the treatment methods of Examples 1-3 can significantly reduce the concentrations of cellulose, hemicellulose, sulfate and COD in the effluent, and do not need to strictly control the pH value of the influent. The treatment effect is stable, the efficiency is high, the treatment cost is low, and the management and operation are simple, which meet the requirements of treating wastewater with high concentrations of cellulose, hemicellulose, sulfate and COD.

[0086] The above description is only examples of the present application, and the protection scope of the present application is not limited by these specific examples, but is determined by the claims of the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. within the technical thought and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for integrated treatment of pulp and papermaking wastewater, characterized by, The method comprises the following steps: The pulp and papermaking wastewater to be treated is pumped into a multi-stage anaerobic reactor, and a composite microbial agent is added thereto, the adding amount of the composite microbial agent being 0.1wt%-5wt% of the pulp and papermaking wastewater to be treated, the fermentation temperature being 28-35℃, and the fermentation time being 4-50h, the produced biogas entering a gas collecting chamber, and the sludge being concentrated to a sludge collecting area through natural sedimentation, and the clear water being collected to a water outlet tank and discharged through a water outlet and a drain tank; The multi-stage anaerobic reactor is a 2-6 stage anaerobic reactor; the composite microbial agent comprises Lactobacillus fermentum and Arcobacter ellisii; and the volume ratio of the Lactobacillus fermentum to the Arcobacter ellisii is 1: (0.3-2).

2. The integrated treatment method of pulp and papermaking wastewater according to claim 1, characterized by, The preparation method of the composite microbial agent comprises the following steps: (1) inoculating Lactobacillus fermentum and Arcobacter ellisii liquid cultures into a reinforced Clostridium culture medium, and culturing at 28-32℃ for 5-7d, so that the culture medium becomes turbid; then, the culture medium is transferred to an anaerobic reinforced Clostridium culture medium, and cultured at 28-32℃ for 22-26h, so that the culture medium becomes turbid, and a liquid culture is obtained; (2) filtering pulp and papermaking wastewater after flocculation and sedimentation, adjusting the pH of the wastewater to 7.0-9.0, and adding nutrients to prepare a wastewater culture medium; (3) inoculating the liquid culture obtained in step (1) into the wastewater culture medium, and separately culturing and separately expanding the culture to obtain a plurality of single liquid cultures, and mixing the plurality of single liquid cultures to obtain a seed liquid culture; (4) supplementing 10-20% of auxiliary growth microorganisms to the seed liquid culture to obtain a mixed liquid culture, and domesticating and cultivating the strains in the mixed liquid culture to obtain the composite microbial agent.

3. The integrated treatment method of pulp and papermaking wastewater according to claim 2, characterized by, In step (3), the liquid culture obtained in step (1) is inoculated into the wastewater culture medium at a volume ratio of 40%-60%, and separately cultured at 28-32℃ for 36-60h; then, the liquid culture after the separate culture is inoculated into the wastewater culture medium at a volume ratio of 1%-2%, and separately expanded and cultured at 28-32℃ for 36-60h to obtain a plurality of single liquid cultures.

4. The integrated treatment method of pulp and papermaking wastewater according to claim 2, characterized by, In step (4), the domestication and cultivation comprises the following steps: mixing the mixed liquid culture and the wastewater culture medium at a volume ratio of 1: (2-5), and culturing at 28-32℃ for 36-60h to obtain the composite microbial agent.

5. The integrated treatment method of pulp and papermaking wastewater according to claim 1, characterized by, The concentration of cellulose and hemicellulose in the pulp and papermaking wastewater to be treated is 500-4000mg / L; The concentration of sulfate in the pulp and papermaking wastewater to be treated is 1000mg / L.

6. The integrated treatment method of pulp and papermaking wastewater according to claim 1, characterized by, The concentration of COD in the pulp and papermaking wastewater to be treated is 10000-30000mg / L.

7. The integrated treatment method of pulp and papermaking wastewater according to claim 1, characterized by, The method further comprises the following step of pretreating the pulp and papermaking wastewater to be treated: The pulp and papermaking wastewater is first sequentially subjected to a grid and an inclined screen, then enters a coagulation reaction tank, polyaluminum chloride and polyacrylamide are added, and after being uniformly stirred, the wastewater enters a sedimentation tank for sludge-water separation, and the effluent is the pulp and papermaking wastewater to be treated.

8. Use of the integrated pulp and paper mill wastewater treatment process according to any one of claims 1 to 7 for treating a wastewater comprising cellulose, hemicellulose and sulfate.

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