No matter what kind of Polyacrylamide products, as a Flocculant use, its principle of action is basically the same, the role of play mainly depends on three stages, which is an important reference basis for product selection in the beaker test. Cup test selection is an important reference for its role in the introduction of the current industry, most people believe that the adsorption of bridging, flocculation and precipitation process, and then in more detail that can be divided into coagulation, flocculation, sedimentation of the three phases, both in the laboratory test or on the machine operation of these three phases can be a good indication of the choice of whether the product applies, this paper will be for the coagulation of flocculants, flocculation, sedimentation process for a This paper will introduce the coagulation, flocculation and sedimentation process of flocculant in detail.
1.Coagulation stage: when we add the liquid (flocculant or Polymeric Aluminium Chloride), the liquid is injected into the coagulation tank and the raw water is rapidly coagulated in a very short period of time to form a fine alumina process, at this time, the water body becomes more turbid, which requires that the water flow can produce intense turbulence. Beaker experiments should be fast (250-300 rpm) stirring 10-30S, generally no more than 2min. this time the effect is the best. 2.Flocculation stage: the process of alum growth and coarsening, requiring the appropriate degree of turbulence and sufficient residence time (10-15min), to the late stage can be observed in a large number of alum gathered slowly sinking, the formation of a clear surface layer. For the beaker test, stir at 150 rpm for about 6 minutes, then at 60 rpm for about 4 minutes until it is in suspension. Check how the reaction, if the effect is not ideal to adjust in time.
3.Settling stage: the treatment of domestic sewage and organic wastewater, the product in the matching or alkaline medium are showing cationic, so that the suspended particles in the sewage with a negative charge sewage Flocculation and precipitation. It is in the settling tank for flocculant settling process, the requirement of slow water flow, in order to improve the efficiency of the general use of inclined tube (plate) settling tank (the best use of air flotation method to separate flocs), a large number of coarse alumina by the wall of the inclined tube (plate) blocked and deposited on the bottom of the pool, the upper water for the clarified water, the remaining small particle size, density of the small view of the flower while slowly falling, while continuing to collide with each other knot big, to the late residual turbidity is basically unchanged.
