CN114105402A - Papermaking white water anion garbage control process - Google Patents
Papermaking white water anion garbage control process Download PDFInfo
- Publication number
- CN114105402A CN114105402A CN202111234744.6A CN202111234744A CN114105402A CN 114105402 A CN114105402 A CN 114105402A CN 202111234744 A CN202111234744 A CN 202111234744A CN 114105402 A CN114105402 A CN 114105402A
- Authority
- CN
- China
- Prior art keywords
- white water
- anion
- papermaking
- rubbish
- biological enzyme
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 59
- 239000010813 municipal solid waste Substances 0.000 title claims abstract description 52
- 150000001450 anions Chemical class 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 title claims abstract description 23
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 50
- 125000000129 anionic group Chemical group 0.000 claims abstract description 32
- 108090000790 Enzymes Proteins 0.000 claims abstract description 29
- 102000004190 Enzymes Human genes 0.000 claims abstract description 29
- 230000015556 catabolic process Effects 0.000 claims abstract description 12
- 238000006731 degradation reaction Methods 0.000 claims abstract description 12
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 10
- 244000005700 microbiome Species 0.000 claims abstract description 6
- 238000006065 biodegradation reaction Methods 0.000 claims abstract description 4
- 229940088598 enzyme Drugs 0.000 claims description 26
- 229920002401 polyacrylamide Polymers 0.000 claims description 14
- 241000193830 Bacillus <bacterium> Species 0.000 claims description 6
- 108010059892 Cellulase Proteins 0.000 claims description 6
- 108010029541 Laccase Proteins 0.000 claims description 6
- 108010059820 Polygalacturonase Proteins 0.000 claims description 6
- 229940106157 cellulase Drugs 0.000 claims description 6
- 229920001577 copolymer Polymers 0.000 claims description 6
- 239000008367 deionised water Substances 0.000 claims description 6
- 229910021641 deionized water Inorganic materials 0.000 claims description 6
- 108010093305 exopolygalacturonase Proteins 0.000 claims description 6
- 238000007873 sieving Methods 0.000 claims description 6
- 241001495402 Nitrococcus Species 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 claims description 2
- 239000002516 radical scavenger Substances 0.000 claims 1
- 239000002699 waste material Substances 0.000 claims 1
- 239000000835 fiber Substances 0.000 abstract description 6
- 239000012535 impurity Substances 0.000 abstract description 6
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 238000001179 sorption measurement Methods 0.000 abstract description 3
- 238000010790 dilution Methods 0.000 abstract description 2
- 239000012895 dilution Substances 0.000 abstract description 2
- 238000001914 filtration Methods 0.000 abstract 1
- 239000000123 paper Substances 0.000 description 12
- 238000009825 accumulation Methods 0.000 description 3
- 239000010893 paper waste Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 1
- 206010003549 asthenia Diseases 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/285—Treatment of water, waste water, or sewage by sorption using synthetic organic sorbents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/26—Nature of the water, waste water, sewage or sludge to be treated from the processing of plants or parts thereof
- C02F2103/28—Nature of the water, waste water, sewage or sludge to be treated from the processing of plants or parts thereof from the paper or cellulose industry
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
- C02F3/342—Biological treatment of water, waste water, or sewage characterised by the microorganisms used characterised by the enzymes used
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
- C02F3/348—Biological treatment of water, waste water, or sewage characterised by the microorganisms used characterised by the way or the form in which the microorganisms are added or dosed
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Paper (AREA)
Abstract
The invention provides a process for controlling papermaking white water anionic trash, which comprises the following steps: firstly, adding biological enzyme into white water for primary degradation; adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment; and then the white water after the secondary treatment is screened by adopting activated carbon, wherein microorganisms are also added into the biological enzyme for biodegradation. Adopt biological enzyme to carry out biodegradable to anion rubbish, carry out preliminary degradation dilution to anion rubbish in the white water, adopt the anion rubbish trapping agent of high molecular weight high charge density again, carry out the secondary adsorption to the micromolecule anion rubbish after preliminary degradation and handle, adopt the fibre activated carbon layer of big specific surface area at last to adsorb the filtration to anion rubbish and other impurity floccules that can't the trapping in the white water, can effectively solve and pile up the problem that can't effectively clear away at papermaking process anion rubbish, restrain anion rubbish's formation and handle anion rubbish that has formed.
Description
Technical Field
The invention belongs to the technical field of papermaking chemical additives, and particularly relates to a papermaking white water anionic garbage control process.
Background
With the large-scale high-speed development of paper machines and increasingly strict environmental requirements, the production cost is reduced due to factors such as gradual shortage of raw material resources, the measures of adopting a large amount of waste paper, improving the closed circulation degree of white water of the paper machine and the like cause adverse effects on the stability of a wet end system of the paper machine. Particularly, in the production of cardboard paper with the utilization rate of waste paper fibers of more than 90%, the recycling of the waste paper fibers causes serious strength loss of the fibers, more and more barrier substances are attached to the pulp, the whole wet end environment is more and more complicated, and the problems caused by the accumulation of anionic garbage are more and more concerned.
Anionic trash refers to the collective name of all dissolved and anionic polymeric (oligomeric and polymeric) and colloidal anionic species present in the wet end of the paper machine. Due to the requirements of water saving and environmental protection, the degree of white water sealing of modern paper machines is increased more and more, and because most of the suspension and dissolved matters in the white water have anionic charges, the closed circulation of the white water can cause more and more anionic trash in the system to accumulate along with the circulation of the white water, thereby causing serious anionic trash problems. The experimental study of scholars shows that when the content of the anionic trash is more than 0.1%, the filler is greatly reduced, which can greatly affect the quality problem of paper and cause other problems to affect the production efficiency of a paper machine, for example, the change of the paper strength causes the increase of the number of broken ends of the paper machine, thereby affecting the running performance of the paper machine. The formation of anionic trash is complicated and difficult to avoid, and the size of the anionic trash is almost less than 10 μm, so that the anionic trash is one of the problems which need to be solved urgently in the pulp and paper making at present.
Disclosure of Invention
In order to solve the defects in the prior art, the invention discloses a process for controlling anionic trash in papermaking white water, which solves the problem that the accumulation of anionic trash can not be effectively removed in the papermaking process by a composite treatment process.
A process for controlling papermaking white water anionic trash comprises the following steps:
adding biological enzyme into the white water for primary degradation;
adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment;
sieving the secondary treatment white water by using active carbon;
wherein the biological enzyme is added with microorganism for biodegradation.
Furthermore, the components of the biological enzyme comprise, by weight, 5-15 parts of cellulase, 5-15 parts of pectinase, 5-10 parts of laccase and 40-60 parts of deionized water.
Further, the microorganism in the biological enzyme is bacillus and/or nitrococcus.
Further, the anion trapping agent is a polyacrylamide copolymer.
Further, the polyacrylamide copolymer is a zwitterionic copolymer with a molecular weight of 500-2000 ten thousand.
Further, the activated carbon is an activated carbon layer which is made into a fibrous shape.
Compared with the prior art, the invention has the following beneficial effects:
adopt biological enzyme to carry out biodegradation to anion rubbish, carry out preliminary degradation dilution to anion rubbish in the white water, adopt the anion rubbish trapping agent of high molecular weight high charge density again, carry out secondary adsorption to the micromolecule anion rubbish after preliminary degradation and handle, adopt the fibre activated carbon layer of big specific surface area at last to adsorb the anion rubbish that can't the trapping in the white water and other impurity floccules and filter, can effectively solve and pile up the problem that can't effectively clear away at papermaking process anion rubbish, restrain anion rubbish's formation and handle anion rubbish that has formed, reduce the use amount of aluminum sulfate.
Detailed Description
The invention is further described below. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
Example 1
A process for controlling papermaking white water anionic trash comprises the following steps:
first, biological enzymes are added into white water for primary degradation. The biological enzyme comprises, by weight, 5 parts of cellulase, 5 parts of pectinase, 5 parts of laccase and 40 parts of deionized water. Meanwhile, bacillus is added into the biological enzyme, and accounts for 3% of the total amount of the biological enzyme in parts by weight.
And adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment. Wherein the anion garbage collector is polyacrylamide copolymer, the polyacrylamide copolymer is zwitterion copolymer, and the molecular weight is 500-2000 ten thousand.
And sieving the secondary treatment white water by adopting activated carbon. In order to increase the specific surface area of the activated carbon and effectively treat anionic garbage and other impurity floccules which cannot be captured and treated in the white water, the activated carbon is prepared into a fibrous activated carbon layer.
Example 2
A process for controlling papermaking white water anionic trash comprises the following steps:
first, biological enzymes are added into white water for primary degradation. The biological enzyme comprises 8 parts by weight of cellulase, 8 parts by weight of pectinase, 8 parts by weight of laccase and 50 parts by weight of deionized water. Meanwhile, bacillus is added into the biological enzyme, and accounts for 5% of the total amount of the biological enzyme in parts by weight.
And adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment. Wherein the anion garbage collector is polyacrylamide copolymer, the polyacrylamide copolymer is zwitterion copolymer, and the molecular weight is 500-2000 ten thousand.
And sieving the secondary treatment white water by adopting activated carbon. In order to increase the specific surface area of the activated carbon and effectively treat anionic garbage and other impurity floccules which cannot be captured and treated in the white water, the activated carbon is prepared into a fibrous activated carbon layer.
Example 3
A process for controlling papermaking white water anionic trash comprises the following steps:
first, biological enzymes are added into white water for primary degradation. The biological enzyme comprises 12 parts by weight of cellulase, 12 parts by weight of pectinase, 8 parts by weight of laccase and 50 parts by weight of deionized water. Meanwhile, bacillus is added into the biological enzyme, and accounts for 8 percent of the total amount of the biological enzyme in parts by weight.
And adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment. Wherein the anion garbage collector is polyacrylamide copolymer, the polyacrylamide copolymer is zwitterion copolymer, and the molecular weight is 500-2000 ten thousand.
And sieving the secondary treatment white water by adopting activated carbon. In order to increase the specific surface area of the activated carbon and effectively treat anionic garbage and other impurity floccules which cannot be captured and treated in the white water, the activated carbon is prepared into a fibrous activated carbon layer.
Example 4
A process for controlling papermaking white water anionic trash comprises the following steps:
first, biological enzymes are added into white water for primary degradation. The biological enzyme comprises, by weight, 15 parts of cellulase, 15 parts of pectinase, 10 parts of laccase and 60 parts of deionized water. Meanwhile, bacillus is added into the biological enzyme, and accounts for 10% of the total amount of the biological enzyme in parts by weight.
And adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment. Wherein the anion garbage collector is polyacrylamide copolymer, the polyacrylamide copolymer is zwitterion copolymer, and the molecular weight is 500-2000 ten thousand.
And sieving the secondary treatment white water by adopting activated carbon. In order to increase the specific surface area of the activated carbon and effectively treat anionic garbage and other impurity floccules which cannot be captured and treated in the white water, the activated carbon is prepared into a fibrous activated carbon layer.
Test example 1
An in-line experiment is carried out, 100kg of papermaking white water with the same concentration is divided into five parts, and one part is subjected to trapping treatment for 30min only by adopting a cationic polyacrylamide polymer and is marked as a control group. The remaining four portions of white water were treated by the process steps described in examples 1-4, and the removal effect of anionic trash in the five portions of white water was determined, with the results shown in the following table:
according to the treatment process, the problem that the accumulation of anionic garbage cannot be effectively eliminated in the papermaking process can be effectively solved, the formation of anionic garbage is inhibited, and the formed anionic garbage is treated by adopting the steps of primary degradation of biological enzyme and microorganism, trapping treatment by adopting a polyacrylamide copolymer and adsorption treatment by adopting fiber activated carbon.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (6)
1. A papermaking white water anion garbage control process is characterized by comprising the following steps:
adding biological enzyme into the white water for primary degradation;
adding an anion trapping agent into the primarily degraded primary treated white water for secondary treatment;
sieving the secondary treatment white water by using active carbon;
wherein the biological enzyme is added with microorganism for biodegradation.
2. The papermaking white water anion waste control process according to claim 1, characterized in that the components of the biological enzyme comprise, by weight, 5-15 parts of cellulase, 5-15 parts of pectinase, 5-10 parts of laccase, and 40-60 parts of deionized water.
3. The papermaking whitewater anionic trash control process of claim 2, wherein the microorganisms in the biological enzymes are bacillus and/or nitrococcus.
4. The papermaking white water anionic trash control process of claim 1, wherein the anion scavenger is a polyacrylamide copolymer.
5. The papermaking white water anionic trash control process of claim 4, wherein the polyacrylamide copolymer is a zwitterionic copolymer with a molecular weight of 500-2000 ten thousand.
6. The papermaking white water anionic trash control process of claim 1, wherein the activated carbon is a fibrous activated carbon layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111234744.6A CN114105402A (en) | 2021-10-22 | 2021-10-22 | Papermaking white water anion garbage control process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111234744.6A CN114105402A (en) | 2021-10-22 | 2021-10-22 | Papermaking white water anion garbage control process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114105402A true CN114105402A (en) | 2022-03-01 |
Family
ID=80376634
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111234744.6A Pending CN114105402A (en) | 2021-10-22 | 2021-10-22 | Papermaking white water anion garbage control process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114105402A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1786342A (en) * | 2005-12-14 | 2006-06-14 | 山东轻工业学院 | Process for biological treating collosol material by pulping paper making technology |
| CN101691719A (en) * | 2009-10-15 | 2010-04-07 | 金东纸业（江苏）股份有限公司 | Control agent of dissolved and colloidal substances in paper machine circulating off-machine water and use method thereof |
| CN102002889A (en) * | 2010-10-29 | 2011-04-06 | 天津市奥东化工有限公司 | Special anion garbage capturing agent for paper making |
| CN104005250A (en) * | 2013-02-26 | 2014-08-27 | 南京林业大学 | Method for eliminating starch interferent in OCC raw material papermaking white water |
| CN108191166A (en) * | 2017-08-01 | 2018-06-22 | 王建玲 | Recycling device and treatment method of thick white water for papermaking |
| CN111320330A (en) * | 2020-03-18 | 2020-06-23 | 长沙理工大学 | Zero discharge method of waste water in paper burning production |
| CN111406136A (en) * | 2017-10-03 | 2020-07-10 | 索理思科技公司 | Chemical efficiency enhancement in papermaking process |
| CN112301780A (en) * | 2020-09-18 | 2021-02-02 | 江苏理文造纸有限公司 | Anionic garbage control process for papermaking system |
-
2021
- 2021-10-22 CN CN202111234744.6A patent/CN114105402A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1786342A (en) * | 2005-12-14 | 2006-06-14 | 山东轻工业学院 | Process for biological treating collosol material by pulping paper making technology |
| CN101691719A (en) * | 2009-10-15 | 2010-04-07 | 金东纸业（江苏）股份有限公司 | Control agent of dissolved and colloidal substances in paper machine circulating off-machine water and use method thereof |
| CN102002889A (en) * | 2010-10-29 | 2011-04-06 | 天津市奥东化工有限公司 | Special anion garbage capturing agent for paper making |
| CN104005250A (en) * | 2013-02-26 | 2014-08-27 | 南京林业大学 | Method for eliminating starch interferent in OCC raw material papermaking white water |
| CN108191166A (en) * | 2017-08-01 | 2018-06-22 | 王建玲 | Recycling device and treatment method of thick white water for papermaking |
| CN111406136A (en) * | 2017-10-03 | 2020-07-10 | 索理思科技公司 | Chemical efficiency enhancement in papermaking process |
| CN111320330A (en) * | 2020-03-18 | 2020-06-23 | 长沙理工大学 | Zero discharge method of waste water in paper burning production |
| CN112301780A (en) * | 2020-09-18 | 2021-02-02 | 江苏理文造纸有限公司 | Anionic garbage control process for papermaking system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Bajpai | Solving the problems of recycled fiber processing with enzymes | |
| Miao et al. | Advances in the control of dissolved and colloidal substances present in papermaking processes: a brief review | |
| CN102517949B (en) | Environmentally friendly waste paper deinking method | |
| CN101725069B (en) | Method for improving removal effect of ink in waste paper pulp | |
| CN111406136A (en) | Chemical efficiency enhancement in papermaking process | |
| CN1763305A (en) | Enzymatic deinking method for waste newspaper | |
| CN1313918A (en) | Method of removing and preventing the buildup of contaminants in papermaking processes | |
| CN108035190A (en) | A kind of high humility waste paper manufactures reel copy paper method | |
| CN100497815C (en) | Process for biological treating collosol material by pulping paper making technology | |
| CN114105402A (en) | Papermaking white water anion garbage control process | |
| CN112301780A (en) | Anionic garbage control process for papermaking system | |
| CN101555673A (en) | Formulation of environment-friendly paperboard regenerated by papermaking sludge and waste textile fibre material | |
| CN110714353A (en) | Treatment process for improving multi-disc drainage of papermaking white water | |
| CN101418287B (en) | Aspergillus niger liquid state fermentation pectic enzyme and control to colloidal matter in white water and paper stuff | |
| CN105735024A (en) | Treatment method for coating waste water and coating broke | |
| CN109821896B (en) | Method for extracting starch organic matter from waste paper pulp and purifying pulp by enzyme pretreatment | |
| CN104262606A (en) | Polystyrene phenol polyoxy alkyl polymer as well as preparation method and application thereof | |
| CN103437228B (en) | A kind of method that can reduce waste paper fibre damage in the dense pulping process of height | |
| CN106192532B (en) | Sludge modification and reuse method | |
| US8562787B2 (en) | Method for producing paper | |
| CN104695261A (en) | Biological enzyme composition for synchronous treatment of newsprint paper ink and sticker, and application thereof | |
| CN114108356B (en) | Papermaking white water anion garbage recycling process | |
| CN112160180A (en) | Production process of biochemical mechanical pulp | |
| CN113605136B (en) | Method for recycling waste paper pulp | |
| CN205775599U (en) | A kind of plain boiled water tower for processing mthod of white water from paper making and system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |