In order to better flocculate and precipitate polyaluminum chloride, the type of polyaluminum chloride should be selected in combination with the water quality of the sewage. Only by finding the right type can achieve twice the result with half the effort. Below, polyaluminum chloride manufacturers will analyze the four processes of polyaluminum chloride in the suitable water treatment process.
1. The coagulation stage of PAC polyaluminum chloride flocculant: the liquid injection coagulation and the rapid coagulation of the raw water form a process of fine alum in a very short time. At this moment, the water body becomes more polluted, which requires the water flow to have severe turbulence. In the beaker test, it is advisable to mix quickly (250-300 rpm) for 10-30s, generally not exceeding 2min.
2. The flocculation stage of PAC polyaluminum chloride flocculant: First, the process of the growth and thickening of the flocculent flower requires an appropriate degree of turbulence and sufficient residence time (10-15min). Shen, forming a clear layer on the outside. In the beaker test, the mixture was first stirred at 150 rpm for about 6 minutes, and then stirred at 60 rpm for about 4 minutes to a suspended state.
3. Settlement stage of PAC polyaluminum chloride flocculant: it is the process of floc settling in the settling tank, which requires slow water flow. In order to improve the efficiency, the inclined tube (plate type) settling tank is generally used (the air flotation method is preferably used to separate the flocs). ), a lot of thick alum flowers are obstructed by the wall of the inclined pipe (plate) and accumulate at the bottom of the pool, the upper layer water is clarified water, and the remaining alum flowers with small particle size and small density slowly descend while continuing to collide with each other. The residual turbidity does not change at all. The beaker test should be slowed at 20-30 rpm for 5 minutes, and then quiet for 10 minutes to measure the residual turbidity.
4. Strengthening filtration is mainly to reasonably select the filter layer structure and filter aid to improve the removal rate of the filter, which is an important measure to further purify the water quality.