Polyacrylamide application range and action mechanism
Polyacrylamide is an organic polymer flocculant, relative to other flocculant products, so through bridging, charge neutralization and colloidal particle surface adsorption, so that colloidal particles gather, the formation of flocs, so that it is separated from water.
Polyacrylamide mainly through electrostatic adsorption, electric neutralization instability, double electric layer compression, bridging, mesh and other forms of action will pollutant particles gathered into dense large particles, sedimentation under the action of gravity, so that the pollutant flocculation from the water, so as to achieve the purpose of sewage treatment. Sewage treatment chemicals, is to rely on the advantages of physical and chemical removal of BOD, COD, SS, N, P and heavy metal ions, by improving the aerobic pool of microbial activity, accelerate the speed of the oxidative decomposition of organic matter in water, improve the efficiency of oxygen transfer, stimulate the rapid proliferation of aerobic microbial population, greatly improve the utilization rate of oxygen in water, improve sludge settling property, Improve effluent water quality fundamentally.
Appearance: powder or water
Technical indicators: in line with national standards
(1) urban sewage purification treatment
(2) including electroplating, paper making, printing and dyeing, bleaching, tanning and other industrial wastewater purification treatment
(3) dehydration and desiccation of various precipitation sludge
Water purification flocculant polyacrylamide has oil and water separation, decolorization, flocculation and other functions, and can be used with common inorganic, organic flocculant, coagulant aid.
Polyacrylamide appearance is white powder particles, molecular weight from 6 million to 25 million water solubility, can be dissolved in any proportion in water and insoluble in organic solvents. The effective PH range is 7 to 14. It is highly polymer electrolyte in neutral alkaline media and is sensitive to saline electrolytes and can cross-link with high-priced metal ions to form insoluble colloids. Anionic PAM is used in sewage flocculant of mine, power plant and coal washing industry.
Polyacrylamide product features:
1) flocculation: PAM can make suspended substances through electric neutralization, bridging adsorption, flocculation.
2) bonding: through mechanical, physical and chemical effects, the bonding effect.
3) resistance reduction: PAM can effectively reduce the frictional resistance of fluid, adding trace PAM in water can reduce the resistance by 50-80%.
4) thickening: PAM has thickening effect under neutral and acidic conditions, PH value is above 10.
The use of sewage treatment drugs, water purification flocculant can be dissolved according to the shallow powder and wastewater in a certain proportion of air flotation, flotation, sedimentation or other wastewater treatment equipment.
Due to water quality conditions, technological conditions and the number of oil containing impurities vary, usually the exact amount should be determined after a small test.
Usage of polyacrylamide
1. Dissolution method before use, dissolve the solid particles into an aqueous solution with a concentration of 1 ‰ - 5 ‰ in order to give full play to their effectiveness quickly. When adding drugs, the gradual domestic drug method shall be adopted, which shall be slowly put into water, so that they can be evenly dispersed and dissolved in water
2. The solution is usually added with an aqueous solution of about 0.5 ‰ - 1 ‰. However, in the case of high concentration and high viscosity of the suspension, it is recommended to further dilute the aqueous solution to 0.1 ‰, which will be easy to mix and give full play to the effect
3. The molecular weight of cation is lower than that of anion, so the viscosity is weaker than that of anion. Therefore, the concentration standard of cation and non-ion ratio is slightly higher than that of anion. (depending on the situation, the concentration can also be adjusted appropriately according to the water concentration. The concentration can be increased appropriately for high turbidity and low turbidity). The recommended concentration is 5 ‰ - 1%
matters needing attention:
1. The preparation of polyacrylamide aqueous solution shall be carried out in enamel, galvanized, aluminum or plastic barrels, and shall not be prepared and stored in iron containers
2. When dissolving, pay attention to evenly and slowly adding the product into the dissolver with stirring and heating measures, avoid solid deposition, prepare the solution at appropriate temperature, and avoid excessive mechanical shear for a long time. It is recommended that the agitator should be 60-200 rpm, otherwise it will lead to polymer degradation and affect the use effect
3. Polyacrylamide aqueous solution shall be used and prepared now. When the solution is placed for a long time, its performance will gradually decrease depending on the water quality
4. After adding flocculant aqueous solution to the suspension, if it is stirred violently for a long time, the formed flocs will be destroyed. Application field, purpose, polymer type, specification, dosage and ratio concentration. Aluminum smelting in furnace, aluminum sulfate circulating water, In the production process, remove 5 / 10 million of impurity anions, clarify and remove 8-12 million / 1 of calcium and magnesium anions with 3-5 g of brine per ton, produce 15-18 million / 3 of viscosity anions that increase bentonite with 1-2 g of bentonite per ton, use 2-3 g of concrete water reducer anions with 5-8 million / 1.2% and 1.2kg of polyacrylamide per ton
Application scope: (PAM has strong applicability) 1. It is used as retention aid and reinforcing agent in papermaking process. 2. It is used as coagulant aid, flocculant and sludge dehydrating agent in water treatment. 3. It is used as precipitation agent and oil displacement agent in oil drilling and production. 4. PAM is also widely used in thickening, stabilizing colloid, drag reduction, bonding, film-forming, biomedical materials, etc