catalogue
Chapter 1 Introduction to ............................................................................................................... 1
1. 1 poplar pulping ............................................................................................................ 2
1. 1 poplar fiber characteristics and chemical composition .................................................................. 2
1. 1.2 Development of Poplar Chemical Mechanical Pulp .......................................................................... 3
1. 1.3 anionic garbage .......................................................... in poplar chemical mechanical pulp 4
1.2 Source of dissolved and colloidal substances in white water ........................................................................ 5
1.2. 1 wood raw material .................................................................................................. 5
1.2.2 waste paper recycling in .................................................................................................. 6
1.2.3 chemical additive .............................................................................................. VII
1.3 influence of DCS on papermaking system and paper quality ................................................................. 8
1.3. 1 Influence on paper quality .................................................................................. 8
1.3.2 system corrosion and blockage of .................................................................................. 9
1.3.3 changes in production conditions ...................................................................................... 9
1.4 separation and analysis method of DCS components in chemical mechanical pulp white water ............................................. 10
1.4. 1 .................................................................................... by centrifugal filtration 10
1.4.2 chemical separation analysis method .................................................................................... 10
1.4.3 ion exchange chromatography ............................................................................ 10
1.4.4 Determination of parameters of white water DCS components ................................................................... 1 1
1.4.5 instrumental analysis method ........................................................................................ 1 1.
1.5 DCS removal technology in white water ................................................................................. 13
1.5. 1 membrane filtration technology ............................................................................................ 14
1.5.2 chemical flocculation ................................................................................................. 15
1.5.3 Flotation ..................................................................................................... 16
1.5.4 biological bacteria treatment ............................................................................................. 16
.................................................................................................... was treated with 1.5.5 enzyme 17.
1.5.6 oxidation treatment ................................................................................................ 18
1.5.7 evaporation technology ................................................................................................ 18
1.5.8 ................................................................................18 added modified flaky zeolite.
1.5.9 frozen crystallization method ............................................................................................ 19
1.5. 10 Washing ...................................................................................................... 19
1.5. 1 1 ......................................................................... 19.
1.6 research purpose, significance and content of the paper ...................................................................... 19I
1.6. 1 purpose and significance of the study ................................................................................. 19
1.6.2 research content ................................................................................................. 20
Chapter II Analysis of the Characteristics of Dissolved Matter and Colloidal Matter in Poplar CMP ........................................... 2 1
2. 1 experimental materials and methods ............................................................................................... 2 1
2. 1. 1 experimental raw material and drug ..................................................................................... 2 1
2. 1.2 experimental method ................................................................................................. 2 1
2.2 Results and Discussion ....................................................................................................... 24
2.2. 1 analysis of macro characteristics of DCS in simulated white water ....................................................... 24
2.2.2 particle size analysis of DCS in water samples ....................................................................... 3 1
2.2.3 DCS-MS analysis of fatty acids and resin acids in DCS .............................................. 32
2.2.4 DCS-MS analysis of carbohydrates in DCS ...................................................... 36
2.3 Summary of ................................................................................................................... 40
Chapter III Effects of Dissolved and Colloidal Substances on the Properties of Pulp ............................................................... 42
3. 1 experimental ................................................................................................................... 42
3. 1. 1 raw material ......................................................................................................... 42
3. 1.2 experimental method ................................................................................................. 43
3.2 Results and Discussion ....................................................................................................... 44
3.2. The influence of1DCS on the optical properties of paper ................................................................. 44
3.2.2 Influence of DCS on Paper Thickness ..................................................................... 45
3.2.3 Influence of DCS on Broken Paper Length ..................................................................... 46
3.2.4 Influence of DCS on Paper Tear Index ................................................................. 47
3.2.5 Influence of DCS on bursting index of paper ................................................................. 47
3.2.7 The influence of DCS on stereotypes ................................................................................. 48
3.2.8 Influence of DCS on fiber retention and drainage performance ..................................................... 49
3.3 Conclusion ................................................................................................................... 50
Chapter IV Biological enzyme treatment and cationic polymer treatment of DCS ............................................................ 51
4. 1 experimental materials and methods ............................................................................................... 5 1
4. 1. 1 experimental raw material ................................................................................................. 5 1
4.2 experimental method ........................................................................................................... 5 1
4.3 Results and Discussion ....................................................................................................... 52
4.3. 1 Effect of enzyme treatment on the properties of DCS water sample ............................................................... 52
4.3.2 Influence of cationic polymer dosage on its interaction with DCS ............................... 56
4.3.3 Effect of Cationic Polymer Combined with Enzyme Treatment on Cationic Demand of Water Samples ..................... 62
4.4 Summary of ................................................................................................................... 64
The fifth chapter conclusion and prospect ..................................................................................................... 65
Observation The adsorption of DCS on fiber by ....................................................... 48III was observed by scanning electron microscope.
Refer to ........................................................................................................................ 67
Due to ................................................................................................................................ 78
Abstract of .................................................................................... 79, a paper published during his master's study.
In recent years, more and more attention has been paid to high yield chemical mechanical pulp. In the pulping process of chemical mechanical pulp, it will
Produce a large number of dissolve and colloidal substances (DCS)
Include resin acids, fatty acids, polysaccharides, pectin acids, lignin substances and the like. These substances are released into the mud system.
This will have a serious impact on wet-end operation and product quality.
In this paper, APMP poplar and BCTMP poplar were used as raw materials to study the dissolved and colloidal substances in pulp.
This research. Firstly, DCS in pulp was characterized, and its chemical composition was analyzed by GC-MS technology.
Conduct analysis; Secondly, the effects on physical properties, optical properties and drainage properties of pulp were studied. most
The effects of cationic polymer and pectinase treatment on DCS yield were studied.
The results show that the content of DS in DCS of coal slurry system is about 60%, and the content of ash is about 60%.
About 50%. The cation demand and turbidity of DCS are mainly contributed by colloidal substances. Colloidal substances on water samples
The concentration of dissolved substances is the decisive factor for the conductivity of water samples. By GC-MS
Eight fatty acids in MTBE extract were quantitatively determined by analyzing water samples: dodecanoic acid, pentadecanoic acid, palmitic acid,
Heptadecanoic acid, linolenic acid, stearic acid, linoleic acid, oleic acid. Analysis of carbohydrates in water samples by gas chromatography-mass spectrometry
Six components were quantitatively determined: xylose, arabinose, glucose, galactose and galactopyranose.
Uronic acid, mannose.
DCS in pulp water system has a very adverse effect on the whiteness and physical strength of paper. Storage of documentary credit
Leading to the decline of paper whiteness. Colloidal substances in DCS affect the hydrogen bond between fibers and reduce the hydrogen bond between fibers.
Binding force, resulting in paper tensile strength, bursting strength, tear strength decreased. With the concentration of DCS in the system
With the increase of the dosage of cationic polyacrylamide, the retention and drainage aid effect of cationic polyacrylamide decreased obviously. This is mainly due to cationic polymerization.
Materials are preferentially adsorbed on DCS instead of fibers, forming polyelectrolyte complexes with DCS, thus reducing
The ability of cationic polyacrylamide to flocculate particles is discussed, which affects the drainage performance of mud.
Pectinase can degrade pectin in DCS. Treating DCS water with pectinase can reduce the production of DCS water.
Cation requirements. When the dosage of enzyme is 30APSU/L and the treatment time is 60 minutes, APMP and BCTMP.
The cation demand of water samples is lower than that of control samples by 24.2% and 20.3% respectively. The addition of cationic polymer can make
DCS is unstable, which effectively reduces the cation demand of water samples. CPAM and CPAM with high molecular weight and low charge density
Cationic starch destroys the stability of DCS through bridging mechanism, while PDADMAC with low molecular weight and high charge density
Charge patch or charge neutralization mechanism makes DCS unstable. The combination of cationic polymer and biological treatment may
More effectively reduce the cation demand of water samples.
Keywords: APMP；; ; BCTMP； Dissolved and colloidal substances; pectic acid