Polyacrylamide dissolution: the solid powder should be made into an aqueous solution. In order to prevent the fisheye phenomenon of the powder caking in the dissolution process, you can add half a warm water (not more than 60 ° C) in the dissolution tank, stir well, and then slowly add the powder, and then add the remaining water, stir until completely dissolved. Under normal circumstances, the concentration of the aqueous solution is 0.1-0.3%, diluted again after use, the storage time of the solution shall not exceed 5 days, as far as possible to use the current, in the dosing of the solution should be used in multiple points of continuous dosing, so that its role is fully played.
Add polyacrylamide to dissolve: Configure enamel, galvanized, aluminum products or plastic buckets, try to avoid iron containers, this product should be slowly added to the agitator, should avoid large, suitable for room temperature or 60℃ water, agitating the blade without edges, the speed is not too fast, otherwise it will lead to product degradation and loss of effect.
This product is white or yellowish powder, molecular weight between 400-20 million, solid products for white or light yellow powder, polyacrylamide flocculant, polymer organic compounds, its molecular weight is mostly between millions to 20 million, some even close to 20 million. Therefore, its dissolution method is completely different from inorganic small molecular iron salt and aluminum salt flocculant. In general, the following principles should be followed:
1. Polyacrylamide powder cannot be directly added to sewage. Before application, it must be dissolved in water first, and then treated with its aqueous solution.
2. The water in which the powdered polymer is dissolved should be clean water (such as tap water), not sewage, and usually does not require heating. Below 5OC, the dissolution rate is very slow. With the increase of temperature, the temperature rises, and more than 40 degrees Celsius will accelerate degradation and affect the use effect. Polymer solution is usually suitable for the preparation of tap water, but strong acid, strong alkali, high salt water is not suitable for preparation.
3. We recommend to use a polymer solution with a concentration of 0.1%-0.3%, that is, to add 1-3 grams of polymer powder to 1 liter of water. The selection of concentration should consider the following factors:
Small pot, daily large dose formula, it is recommended to match the amount of slightly heavier (such as 0.3%);
The amount of polymer is large, and the distribution is relatively thin (such as 0.1%);
Due to equipment factors, the polymer solution is thrown into the sewage, if the dispersion effect of the equipment is not good, it is recommended to use a dilute ratio.
The high concentration of high polymer will cause the motor load to be too large, so that it will disperse badly after entering the sewage and affect the use effect. A little watering down can improve the effect.
4. Do not use the centrifugal pump to transport the mixed solution, so as not to cause polymer shear degradation due to high-speed rotation of the blade.
5. The specific method of preparation is as follows: add a certain amount of water to a container (such as a laboratory beaker, a factory preparation tank), calculate the required polymer, and calculate the amount of polymer required in clean water, weigh out the polymer; Open the electric mixer, stir the water out of the whirlpool, the linear speed of the agitator blade should not exceed 8 meters per second, otherwise it will cause polymer degradation; But not too slowly, so that the polymer particles do not rise to the surface, or sink in the water and form clumps. These polymers are placed in a vortex until they disperse. The study found that after the macromolecular particles entered the water, there was no adhesion between them. Stir for a moment, so that the polymer particles completely dissolve, into a uniform, transparent, thick, invisible solution. The method of determining the mixing time is as follows: when the water temperature is high in summer, the canionic polymer is mixed for about 1 hour, and the non-ionic polymer is mixed for about 2 hours; In winter, when the water temperature is low, the anionic polymer is stirred for 1.5 hours, and the non-ionic polymer is stirred for about 3 hours. With the increase of the preparation concentration, the dissolution rate of the polymer is accelerated, and the uneven or insufficient solubility will affect the use effect.
