What are the factors that affect the use of polyacrylamide?

①The selection of polyacrylamide models

Cationic polyacrylamide is suitable for two purposes: highly toxic, organic-containing sewage flocculation treatment and organic sludge dewatering process.

Anionic polyacrylamide is suitable for flocculation treatment of sewage with large suspended particles, high turbidity and positive charge.

Due to the activity of acylamines on the side chains of nonionic functional group molecules, nonionic polyacrylamide can exhibit a powerful flocculation function in acidic water.

② Molecular weight of flocculant

The larger the molecular weight of the flocculant, the better the flocculation effect.However, the molecular weight is too large, it is difficult to dissolve and the manufacturing cost is also high. You need to choose the most suitable one according to the sewage situation. The commonly used molecular weight is 3-18 million.

③The amount of flocculant polyacrylamide

The dosage is generally based on different water quality and the dosage will vary. If the dosage is small in sewage, the flocculation effect will not be achieved. If the dosage is large, the liquid will become viscous. Generally, it is recommended to do a beaker flocculation experiment before using the machine. Prevail.

④PAM The proportion of polyacrylamide when dissolved

The dissolution ratio of anionic PAM and nonionic polyacrylamide is one thousandth, and the optimal dissolution ratio of cationic polyacrylamide is two thousandths.

⑤The pH value of water
The pH value of water has a great influence on the use effect of inorganic flocculants. The size of the pH value is related to the type of flocculant selected, the dosage and the coagulation and precipitation effect.

⑥The temperature of the water

The water temperature affects the hydrolysis rate of the flocculant and the speed and structure of alum flower formation.The hydrolysis of coagulation is mostly an endothermic reaction. When the water temperature is low, the hydrolysis rate is slow and incomplete.At low temperatures, the viscosity of water is large, the Brownian motion is weakened, and the number of collisions between the colloidal particles of the flocculant and the impurity particles in the water is reduced. At the same time, the shear force of the water increases, hindering the mutual adhesion of the coagulated flocs.

⑦Flocculant dosing sequence

When using a variety of flocculants, it is necessary to determine the optimal dosing sequence through experiments.Generally speaking, when inorganic flocculants are used in combination with organic flocculants, inorganic flocculants should be added first, and then organic flocculants should be added.

Stirring speed

In the mixing stage, the flocculant and water are required to be mixed quickly and evenly, and in the reaction stage, it is necessary not only to create sufficient collision opportunities and good adsorption conditions for the flocculant to have sufficient growth opportunities, but also to prevent the generated small flocculants from being broken, so the stirring intensity should be gradually reduced, and the reaction time should be long enough.The speed of the mixer should generally be controlled at 50-250r/min.

Impurity composition in water

Uneven size of impurity particles in water is beneficial to coagulation, and small and uniform coagulation can lead to poor coagulation effect.The concentration of impurity particles is too low, which is often detrimental to coagulation. At this time, reflux of the precipitate or the addition of coagulant can improve the coagulation effect.When the impurity particles in the water contain a large amount of organic matter, the coagulation effect will deteriorate, and it is necessary to increase the dosage or add oxidants and other coagulation-promoting agents.

Hydraulic conditions

In the mixing stage, the flocculant and water are required to be mixed quickly and evenly, and in the reaction stage, it is necessary not only to create sufficient collision opportunities and good adsorption conditions for the flocculant to have sufficient growth opportunities, but also to prevent the generated small flocculants from being broken, so the stirring intensity should be gradually reduced, and the reaction time should be long enough.