Product Introduction:
Polyacrylamide (PAM) is a linear polymer with the chemical formula (C3H5NO) n. At room temperature, it is a crystalline solid, and the products include glue, latex, white powder particles, semi transparent beads, and thin films. Good thermal stability. It can dissolve in water in any proportion, and the aqueous solution is a uniform and transparent liquid. Polyacrylamide, as a lubricant, suspension agent, clay stabilizer, oil displacement agent, loss control agent, and thickener, has been widely used in drilling, acidification, fracturing, water plugging, cementing, secondary oil recovery, and tertiary oil recovery. It is an extremely important oilfield chemical.
Functional features:
1. Clarify the purification effect; 2. The promoting effect of settlement;
3. Filtering promoting effect; 4. Thickening and other effects.
5. The retention effect of papermaking; 6. Sludge dewatering effect.
Differences in product pH range:
1. The effective pH range of anionic polyacrylamide is 5-14, with good weak ACID, neutral, and alkaline effects. Suitable for wastewater bodies with positive charges. For example: electroplating plants, steel plants, battery plants, coal washing plants, metallurgical wastewater, sand washing plants, etc.
2. The effective pH range of cationic polyacrylamide is 7-14, and it has good treatment effects for neutral and alkaline water quality. It is suitable for wastewater bodies with negative charges. Such as leather factories, paper mills, municipal Sewage Treatment plants, special metal extraction, etc.
3. The effective pH range of non-ionic polyacrylamide is 2-8, and it has good treatment effects for neutral and acidic water quality. It is suitable for wastewater bodies with complex electrical charges.
Product structure differences:
Cationic polyacrylamide (CPAM): It is a linear polymer compound that, due to its various active functional groups, can form hydrogen bonds by affinity and adsorption with many substances. Mainly flocculation of negatively charged colloids.
Anionic Polyacrylamide (APAM): It is a water-soluble polymer mainly used for the flocculation, sedimentation, and clarification treatment of various industrial wastewater, such as steel plant wastewater, electroplating plant wastewater, metallurgical wastewater, coal washing wastewater, and sludge dewatering. It can also be used for clarification and purification of drinking water. Due to the presence of a certain number of polar groups in its molecular chain, it can adsorb solid particles suspended in water, bridge between particles, or condense particles to form large flocculents through charge neutralization. Therefore, it can accelerate the settling of particles in the suspension, significantly accelerate solution clarification, and promote filtration.
Non ionic polyacrylamide (NPAM): It is a polymer or electrolyte with a certain amount of polar genes in its molecular chain that can adsorb solid particles suspended in water, bridging particles to form large flocculents. It accelerates the settling of particles in the suspension, significantly accelerating the clarification of the solution and promoting filtration. Due to the presence of amide or ionic genes in the molecular chain, its notable feature is high hydrophilicity, which can be dissolved in water in various proportions. Polyacrylamide aqueous solution has good tolerance for electrolytes, such as amine chloride, sodium sulfate, etc., which are not sensitive and are also compatible with surfactants.
Differences in product industry applications:
1. Non ionic polyacrylamide applications
Wastewater treatment agent: When suspended wastewater appears acidic, it is more appropriate to use non-ionic polyacrylamide as a flocculant. This is the adsorption bridging effect of PAM, which causes suspended particles to coagulate and precipitate, achieving the goal of purifying wastewater. It can also be used for the purification of tap water, especially when combined with inorganic flocculants, for the best effect in Water Treatment.
Textile industry additives: Some chemicals can be added to form chemical materials for textile sizing.
Sand prevention and fixation: Dissolve non ionic polyacrylamide into a 0.3% concentration and add crosslinking agent. Spraying it on the desert can play a role in sand prevention and fixation.
Soil moisturizing agent: used as a basic raw material for soil moisturizing agents and various modified polyacrylamide.
2. Application of cationic polyacrylamide
Sludge dewatering: Depending on the nature of the pollution, the corresponding brand of this product can be selected, which can effectively perform gravity sludge dewatering before the sludge enters the pressure filtration. During dehydration, large flocs are produced, which do not stick to the filter cloth and do not flow during pressure filtration. The amount used is small, and the dehydration efficiency is high. The moisture content of the mud cake is below 80%.
Treatment of wastewater and organic wastewater: This product exhibits a positive charge in acidic or alkaline media, which is highly effective in flocculation, sedimentation, and clarification of suspended particles with negative charges in wastewater, such as alcohol factory wastewater, brewery wastewater, monosodium glutamate factory wastewater, sugar factory wastewater, meat and food factory wastewater, beverage factory wastewater, textile printing and dyeing factory wastewater, etc. Cationic polyacrylamide is more effective than anionic polyacrylamide, The effect of non-ionic polyacrylamide or inorganic salts is several times or tens of times higher, as these types of wastewater generally carry negative charges.
Water treatment flocculant for waterworks: This product has the characteristics of low dosage, good effect, and low cost. Farewell to using it in combination with inorganic flocculants, the effect is better.
Oilfield chemicals: such as clay anti swelling agents, thickening agents for oilfield acidification, etc.
Paper additive: Cationic PAM paper enhancer is a water-soluble cationic polymer containing amino formyl groups, which has functions such as reinforcement, retention, and filtration, and can effectively improve the strength of paper. At the same time, this product is also an efficient dispersant.
3. Application of anionic polyacrylamide
Industrial wastewater treatment: For suspended particles, high concentration, particles with positive charges, and water with a neutral or alkaline pH value, the best results are achieved in the treatment of steel plant wastewater, electroplating plant wastewater, metallurgical wastewater, coal washing wastewater, and other wastewater.
Drinking water treatment: Many water plants in China source water from rivers, which have high sediment and mineral content and are relatively turbid. Although they have undergone sedimentation and filtration, they still cannot meet the requirements. Flocculants need to be added, with a dosage of 1/50 of inorganic flocculants, but the effect is several times that of inorganic flocculants. For rivers with severe organic pollution, inorganic flocculants and cationic polyacrylamide can be used in combination to achieve better results.
Recovery of starch lees from starch and alcohol factories: Many starch factories now contain a lot of starch in their wastewater. Anionic polyacrylamide is added to coagulate and precipitate starch particles, and then the precipitate is filtered by a pressure filter to form a cake, which can be used as feed. Alcohol from alcohol factories can also be dehydrated by anionic polyacrylamide and filtered for recovery.
Application features:
Polyacrylamide (PAM) is a general term for polymers obtained by copolymerization of acrylamide homopolymers or other monomers, and is one of the more widely used varieties in water-soluble polymers. Due to the presence of amide groups in the structural units of polyacrylamide, which can easily form hydrogen bonds, it has good water solubility and high chemical activity. It is easy to obtain various modified substances with branched or network structures through grafting or cross-linking, and has a wide range of applications in industries such as petroleum extraction, water treatment, textiles, papermaking, mineral processing, medicine, agriculture, etc. It is known as a "versatile additive". The main application areas abroad are water treatment, papermaking, mining, metallurgy, etc; At present, the largest usage in China is in the oil extraction field, while the fastest growing usage is in the water treatment and papermaking fields.
Application of polyacrylamide industry:
Water treatment field
Water treatment includes Raw Water Treatment, sewage treatment, and Industrial Water Treatment. When used in conjunction with Activated Carbon in raw water treatment, it can be used for the coagulation and clarification of suspended particles in domestic water. Using organic flocculant acrylamide instead of inorganic flocculant can increase the water purification capacity by more than 20% even without modifying the sedimentation tank; In sewage treatment, the use of polyacrylamide can increase the utilization rate of water recycling and can also be used for sludge dewatering; Used as an important formulation agent in industrial water treatment. The largest application of polyacrylamide in foreign countries is in water treatment, and its application in this field is being promoted domestically.
The main role of polyacrylamide in water treatment:
(1) Reduce the amount of flocculant used. Under the premise of achieving the same water quality, the use of polyacrylamide as a coagulant aid in combination with other flocculants can greatly reduce the amount of flocculant used; Under the premise of achieving the same water quality, the use of polyacrylamide as a coagulant aid in combination with other flocculants can greatly reduce the amount of flocculant used;
(2) Improve water quality. In the treatment of drinking water and industrial wastewater, the combination of polyacrylamide and inorganic flocculants can significantly improve water quality;
(3) Improve the strength and settling speed of flocs. The flocs formed by polyacrylamide have high strength and good settling performance, thereby improving the solid-liquid separation speed and facilitating sludge dewatering;
(4) Anti corrosion and anti scaling of circulating cooling systems. The use of polyacrylamide can greatly reduce the amount of inorganic flocculants, thereby avoiding the deposition of inorganic substances on the surface of equipment and slowing down the corrosion and scaling of equipment.
Application in oil recovery
Polyacrylamide is a multifunctional oilfield chemical treatment agent widely used in drilling, cementing, completion, well repair, fracturing, acidification, water injection, water plugging and profile control, and tertiary oil recovery operations, especially in the fields of drilling, water plugging and profile control, and tertiary oil recovery. Polyacrylamide aqueous solution has high viscosity, good thickening, flocculation, and rheological regulation effects, and is used as an oil displacement agent and drilling mud regulator in petroleum exploitation. In the middle and later stages of oil extraction, in order to improve crude oil recovery rate, China currently mainly promotes polymer flooding and ternary composite flooding technologies. By injecting polyacrylamide aqueous solution, the oil water flow rate ratio is improved, resulting in an increase in the crude oil content of the extracted material. Adding polyacrylamide to tertiary oil recovery can increase oil recovery capacity, avoid oil layer breakdown, and improve oil bed recovery rate. China's petroleum industry is the largest user of polyacrylamide. The technological progress of polyacrylamide has promoted the development of China's petroleum industry, and the demand of the petroleum industry has accelerated the pace of technological innovation and industry development of polyacrylamide.
Paper industry
Polyacrylamide is widely used as a retention aid, filter aid, and homogenizer in the papermaking industry to improve paper quality, pulp dewatering performance, retention rate of fine fibers and fillers, reduce raw material consumption and environmental pollution. As a dispersant, it can improve paper uniformity. Polyacrylamide is mainly used in two aspects in the papermaking industry. Firstly, it improves the retention rate of fillers, pigments, etc. to reduce the loss of raw materials and environmental pollution; The second is to improve the strength of the paper. Adding polyacrylamide to paper can improve the retention rate of fine fibers and filler particles on the mesh, and accelerate the dehydration of paper. The mechanism of action of polyacrylamide is that the particles in the slurry coagulate and remain on the filter cloth through electric neutralization or bridging. The formation of flocs can also make the water in the slurry easier to filter out, reduce the loss of fibers in white water, reduce environmental pollution, and improve the efficiency of filtration and sedimentation equipment.
industrial waste water
When adding polyacrylamide to suspended particles in water, the neutralization of electricity and the adsorption bridging effect of the polymer itself can promote the rapid coagulation and sedimentation of suspended particles, achieving separation and clarification effects, thereby improving operational efficiency and reducing operating costs.
The coal industry
Coal washing wastewater, coal slurry water from coal preparation plants, and ground washing wastewater from coal-fired power plants are all mixtures of water and fine coal powder. Their main characteristics are high turbidity, fine particle size of solid matter, and the surface of solid particles often carries negative charges. The repulsive force between isotropic charges keeps these particles in a dispersed state in water, which is affected by gravity and Brownian motion; Due to the interaction between solid particle interfaces in coal slurry water, the properties of coal washing wastewater are quite complex, not only possessing the properties of suspension, but also colloidal properties. In order to quickly precipitate the coal slurry water in the concentration tank, ensure qualified washing water and filter coal slurry production, and ensure efficient and economic operation of production, it is necessary to choose appropriate flocculants to strengthen the treatment of coal slurry water. The series of polymer flocculants developed for coal slurry dewatering in coal washing plants have high dewatering efficiency and are easy to use.
Performance characteristics:
1. Flocculence: PAM can cause suspended substances to undergo electro neutralization, bridging adsorption, and flocculation.
2. Adhesion: It can exert a bonding effect through mechanical, physical, and chemical reactions.
3. Resistance reduction: PAM can effectively reduce the frictional resistance of fluids, and adding trace amounts of PAM to water can reduce resistance by 50-80%.
4. Thickening properties: PAM has a thickening effect under both neutral and acidic conditions, and is easily hydrolyzed when the pH value is above 10. When it forms a semi network structure, thickening will be more pronounced.
Usage and precautions:
1. Dissolved water: It is recommended to use low hardness water with a neutral pH value, and use groundwater. Water that dissolves too much inorganic substances or metal ions can easily reduce product performance.
2. Dissolution time: Dry powder products can achieve optimal performance after being dissolved for 1 hour (it is recommended to dissolve non-ionic dry powder products for more than 2 hours). It is recommended to use the dissolved solution on the same day, preferably not more than 24 hours, otherwise the polyacrylamide solution will quickly degrade, seriously affecting the effectiveness of use.
3. Dissolution concentration: The usual dissolution concentration for cationic products is 0.2% (0.1% -0.5% is feasible); The dissolution concentration of anionic and non-ionic products is 0.1% (0.05% -0.3% feasible).
4. The dissolution operation should be carried out in tanks made of plastic, ceramics, stainless steel, and other materials. The stirring speed should not be too high, generally 200 rpm, and the time should not be less than 1 hour. The water temperature should be appropriately increased by 20-30 ℃ to accelerate dissolution. The highest temperature in the pharmaceutical industry should be less than 60 ℃. When transporting diluted solutions, high shear rotor pumps such as centrifugal pumps should be avoided, and it is best to use low shear pumps such as screw pumps.
5. Full dissolution: When dissolving this product, attention should be paid to the absence of visible snowflake like solid suspensions in the pharmaceutical solution. The automatic dosing device should not have a too fast flow rate to prevent polyacrylamide from clumping and fisheye phenomenon, and to prevent unnecessary troubles caused by pipeline blockage.
Product packaging and storage:
1. Polyacrylamide products are packaged uniformly at 25 kilograms per bag, with plastic moisture-proof film and double-layer packaging in kraft paper bags.
2. The product has a shelf life of 2 years and needs to be stored in a cool, ventilated, and dry place. Pay attention to moisture prevention.
