Three stages of Polyacrylamide in water treatment - CHINAFLOC
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Three stages of Polyacrylamide in water treatment
2014-12-16 13:35:26
  Polyacrylamide  is used in the application of a variety of complex water conditions, and after coagulation it can produce a large size, heavy and strong alum, get the coagulation sedimentation effect satisfactory solution to handle a variety quality problems of water production from complex raw water, the follows are three stages in the treatment process of analysis using polyacrylamide.
  1 The combination stage: is the liquid produced by the injection of polyacrylamide to raw water to form a small alum rapidly in a very short period, then the water becomes more turbid, it requires water can generate intense turbulence. During the beaker experiment we should fast (250-300 rev / min) stir 10-30S, generally no more than 2min. At this moment the effect is the best.
  2 The flocculation stages: alum is growing thicker, requiring an appropriate degree of turbulence and sufficient residence time (10-15min), later it can be observed that a lot of alum are sinking slowly to gather, forming clear surface layer. Beaker experiment at first it should be stirred for about 6 minutes at 150 rpm/min, and then to 60 rpm/min for about 4 minutes to a suspended state. See how they react, if the effect is not obvious, you should adjust.
  3 The settlement stages: sewage and organic wastewater treatment, this product in alkaline medium shows that it’s cationic, so that the sewage effluent suspended particles with a negative charge flocculation. It is the process of settling floc performing in settling tank, requiring slow water flow, in order to improve the efficiency generally oblique tube (plate) is used as settling pond (best to use the flotation separation of floc), a lot of thick alum are prevented by inclined tube (plate) deposited to the bottom of the barrier, the upper is the clarified water, the rest alums with small particle size and small density are gradually decreased, while continuing to collide knot large, substantially unchanged until the latter part of the residual turbidity. Beaker experiment should be slow stirred by 20-30 rpm/min for 5 minutes, and then to settle for 10 minutes, and then measure the turbidity, getting the best dosage to prepare for the follow-up work.
    While learning the flocculation process of polyacrylamide, we can see the second stage flocculation stage is the most important stage, in order to achieve the best effect of water treatment, to let the water quality achieve the discharging standards, we must understand the whole flocculation process of polyacrylamide.
    We also have some points that we should pay some attentions.
  1.Before using flocculantsproduct, you should perform a series of small beaker experiment to determine the amount of the scope and terms of use. According to experience, in general the amount of sewage settling PAM 0.5 ~ 5ppm, the specific amount to determine the best dosage according to SS effluent quality content and miscellaneous.
  2. Before using the product, must be sufficiently soluble to chain extend sufficiently obtained, typically about 0.1% dilution, dissolving operation to be carried out in a plastic container, ceramics, or concrete or the like. Must not dissolve when mixed with the colloidal or PAC, PFC, or else lose efficacy.
  3. In the process, stirring to dissolve, stirring not too much or too severe, cannot place a long time after dissolution, generally not more than 48 hours, PAM solution is to try not to prolonged exposure to iron-like object. Bubble drug ambient temperature must not exceed 60 ℃.
  4. PAM solution delivery, piping to be rough, less elbow to minimize piping losses and turbulence. Pump to use a peristaltic pump (or easy to break so that the effect of lowering the molecular chains).
  5. The use of the process must first add PAC\PFC and other inorganic flocculants, and add after alum to be produced.