Polyacrylamide used in paper mills has good flocculation properties and can reduce frictional resistance between liquids. Polyacrylamide used in the papermaking industry is widely used as a retention agent, filter aid, leveling agent, water treatment agent, etc. in the papermaking field. Its function is to improve the quality of paper, improve the dewatering performance of the slurry, increase the retention rate of fine fibers and fillers, and reduce the consumption of raw materials and environmental pollution.

Polyacrylamide for paper industry

The effect used in papermaking depends on its average molecular weight, ionic properties, ionic strength and the activity of other copolymers. Non-ionic PAM is mainly used to improve the filterability of pulp, increase the strength of dry paper, and increase the retention of fibers and fillers; anionic copolymers are mainly used as dry and wet strengthening agents and retention agents for paper; cationic copolymers are mainly used It is used for papermaking wastewater treatment and filter aid. In addition, it also has a good effect on increasing the retention rate of fillers. In addition, polyacrylamide is also used in papermaking wastewater treatment and fiber recycling.

Polyacrylamide

Anionic polyacrylamide for paper mills:

There are two types of polyacrylamide used in paper mills. One is anionic polyacrylamide. The main reason is that it should have the characteristics of pyrolysis and its viscosity will decrease quickly with the increase of temperature, so as to ensure that the original fiber in the dry paper is not affected Performance. Anionic polyacrylamide is a water-soluble organic polymer, which is easily soluble in water and forms a high-viscosity liquid. It can promote good dispersion of papermaking fibers and excellent paper forming effects at low addition levels, and improve the uniformity of pulp and paper Softness can also increase the strength of paper. In the use of papermaking coating, the papermaking dispersant has high dispersion efficiency, stable coating viscosity, less foam, non-toxic, non-corrosive, can increase the solid content of the coating, and has good fluidity and scrub resistance, and can maintain paper gloss Degree, not easy to become moldy. Papermaking dispersants can also increase the speed of papermaking, save beating time, reduce energy consumption, and have significant economic benefits.

Cationic polyacrylamide for water treatment in paper mills:

If you want to know which polyacrylamide is used in a paper mill, you must first understand the water quality characteristics of the paper mill. The following will introduce Capitel Chemical in detail.

Water quality characteristics of paper mills: Papermaking wastewater contains high COD and suspended solids (SS) content and serious color. The concentration of SS and COD in papermaking wastewater is relatively high. COD consists of two parts: insoluble COD and soluble COD. Generally, insoluble COD accounts for most of the total COD composition. When SS in wastewater is removed, most Insoluble COD is removed at the same time. Therefore, the main problem to be solved in waste paper and papermaking wastewater treatment is to remove SS and COD.

Using air flotation or precipitation method, by adding cationic polyacrylamide, most of SS can be removed, while most of insoluble COD and partially soluble COD and BOD can be removed. The typical treatment process is as follows:

Wastewater → Screen → Cistern → Air flotation or sedimentation → Discharge

Air flotation and sedimentation are both physical and chemical treatment methods, and the treatment effect is related to the selected equipment, process parameters, coagulant, etc. The COD removal rate is generally higher than that of the middle stage water of pulping, usually reaching 70%-85% . For small and medium-sized waste paper paper-making enterprises with a discharge volume of more than 150 m3 of paper waste water and a low concentration, through air flotation or precipitation treatment, the effluent water quality index can meet or approach the national discharge standard.

Polyacrylamide for wastewater treatment in paper mills

Precautions:

1. Dissolution temperature. A certain temperature is required for dissolution to speed up the dissolution. However, if the temperature is too high, the molecular chain of the polymer will be broken and the use effect will be reduced. The most suitable dissolution temperature is below 60℃.

2. Stirring conditions. Dissolution should avoid excessive shearing force stirring, excessive stirring will break the molecular chain, thereby reducing the use effect. Low-speed paddles should be used for mixing, such as anchor type, frame type, multi-layer paddle type, etc. The stirring speed is about 60 rpm. High-speed centrifugal pumps should also be avoided during transportation, and piston pumps or diaphragm pumps are more suitable.

3. Disperse and feed evenly. The key link in the dissolution of polyacrylamide is the uniform dispersion of the feed. After starting the mixer, use a mechanical vibrating screen for feeding (the screen mesh is 10 meshes), try to avoid the production of "large clumps" and "fisheye" insoluble particles, so that the polyacrylamide can be fully dissolved and used well effect. Polyacrylamide for paper industry.

4. Avoid connecting with iron. In the dissolving stirring and conveying dosing system, materials such as plastic, enamel, aluminum, and stainless steel are used.

5. Product selection. When purchasing polyacrylamide products, users should provide sewage/sludge to the flocculant manufacturers as much as possible for polyacrylamide product selection tests. Due to the different raw materials and sewage treatment processes used in the papermaking process of various paper mills, the water quality is still very different. , I still firmly believe that choosing the right flocculant products can help companies save a lot of pharmaceutical costs, and also solve the problem of manufacturers’ drainage compliance as much as possible.

Packaging and storage:

25kg/bag (plastic kraft paper bag lined with plastic bag outside). This product is non-toxic, pay attention to moisture, rain, and avoid sun exposure.

Guangdong Shouxin Environmental Protection Materials Technology Co., Ltd. is a global polyacrylamide brand with stable quality, mainly including cationic polyacrylamide, anionic polyacrylamide, non-ionic polyacrylamide, zwitterionic polyacrylamide, four major products, free on-site sampling , Experimental selection, to provide you with solutions with better effects and lower prices, welcome to consult.

The types and stages of polyacrylamide for papermaking wastewater used from paper mills are widely used in water treatment in the papermaking field. Its role is to reduce the consumption of raw materials and pollution to the environment. The effect used in papermaking depends on its average molecular weight, ionic properties, ionic strength and the activity of other copolymers. Cationic polyacrylamide is mainly used for the treatment of papermaking wastewater and filtering aid. In addition, it has a good effect on improving the retention rate of filler.

The papermaking wastewater contains high levels of COD and suspended solids (SS) and serious color. The concentration of SS and COD in papermaking wastewater is relatively high. COD is composed of two parts: insoluble COD and soluble COD. Generally, insoluble COD accounts for most of the total COD composition. When SS is removed from the wastewater, most of it Insoluble COD is also removed. Therefore, the main problem to be solved in waste paper and papermaking wastewater treatment is to remove SS and COD.

Anionic polyacrylamide for paper mill wastewater, with a molecular weight of about 14 million. Main application: wastewater precipitation.

Cationic polyacrylamide for paper mill wastewater, with a molecular weight of about 12 million. Main application: sludge dewatering.

Types and stages of Polyacrylamide for papermaking wastewater from paper mills. The effect used in papermaking depends on its average molecular weight, ionic properties, ionic strength and the activity of other copolymers. A combination of physicochemical and biochemical treatment is adopted. The general physicochemical and biochemical treatment methods are wastewater → screen → adjustment → precipitation or air floatation → A/O or contact oxidation → secondary sedimentation tank → discharge. In this treatment process scheme, cations are used Polyacrylamide to treat sewage.

Papermaking and papermaking wastewater flocculation and sedimentation treatment of anionic polyacrylamide flocculant, sludge dewatering cationic polyacrylamide flocculant pam, papermaking dispersion of 16 million to 18 million molecular weight polyacrylamide flocculant, papermaking retention retention and filtration quality imported polyacrylamide.

In the papermaking process, the paper fibers and fillers in the pulp are hydrophobic and tend to flocculate into agglomerates, and it is often difficult to produce paper with uniform performance and strength that meets the requirements. It is necessary to add an auxiliary agent to increase the viscosity of the pulp, so as to facilitate the even dispersion of the fibers and fillers, so that the paper produced is even and smooth and flexible without holes, so that the performance of the papermaking is stable, and it is not easy to break the paper and raise the powder during the papermaking. Improve the tensile strength and dry and wet strength of paper products and save paper pulp. The added additive is called paper dispersant.

Paper-making dispersant has high dispersion efficiency, stable coating viscosity, less foam, non-toxic and non-corrosive, can improve the solid content of the coating, and has good fluidity and scrub resistance, can maintain the gloss of the paper product, and is not easy to mold. Paper-making dispersants can also increase the speed of papermaking, save beating time, reduce energy consumption, and have significant economic benefits. It has the characteristics of pyrolysis, its viscosity decreases rapidly with increasing temperature, good water solubility, high viscosity, and good lubricity, so as to ensure that it does not affect the performance of the original fiber in the dried paper. The product is a water-soluble organic polymer, which is easily soluble in water and forms a high-viscosity liquid. It can promote good dispersion of papermaking fibers and excellent paper forming effects at low addition levels, improve pulp uniformity and paper softness , Can also increase the strength properties of paper.

The Papermaking dispersant can show good fiber dispersion effect in a very small amount of addition (less than 1kg per ton of dry pulp). The product is non-ionic, relatively less affected by water quality and other additives, and has stable papermaking performance, and is not easy to break paper and powder. Its advantage is that it can improve the softness and uniformity of the finished paper. The principle of the dispersant is to distribute the solid fine particles as evenly as possible in another incompatible material. That is to say, the internal phase is a coarsely dispersed system composed of insoluble particles distributed in the external phase being liquid or semi-solid. The dispersant can make the solid dispersed particles in the suspension fully wetted and evenly dispersed by the liquid phase, and minimize the separation, aggregation and settling speed of the solid particles in the system to maintain the maximum kinetic stability of the suspension.

Papermaking dispersant can also increase the speed of papermaking, save beating time, reduce energy consumption, and has significant economic benefits. Papermaking dispersants are currently widely used in the production of low-quantitative paper such as toilet paper, newsprint, cigarette paper, tea filter paper, liner paper, napkins, colored crepe paper, electrolytically soluble paper, and electrostatic copy paper.