What is the mechanism of action of the water treatment agent polyaluminum chloride flocculant?
Date of publication：2019-08-01 15:54:23
The colloidal particles in the water are small, the surface is hydrated and charged to make it stable. The flocculant is added to the water and then hydrolyzed into a micelle with a charged colloid and its surrounding ions to form an electric double layer structure. The rapid agitation after administration of the drug promotes the collision chance and the number of collisions between the colloidal particles of the water and the micelles hydrolyzed by the flocculant. The impurity particles in the water first lose stability under the action of the flocculant, and then agglomerate into larger-sized particles, and then precipitate or float in the separation facility.
The product GT of the velocity gradient G and the stirring time T generated by the agitation can indirectly represent the total number of particle collisions throughout the reaction time, and the effect of the coagulation reaction can be controlled by changing the GT value. Generally, the GT value is between 104 and 105. Considering the influence of impurity particle concentration on the collision, the GTC value can be used as the control parameter to characterize the coagulation effect, where C is the mass concentration of the impurity particles in the sewage, and the GTC value is recommended. About 100.
The process of causing the flocculant to diffuse rapidly into the water and mix well with all of the wastewater is to mix. The impurity particles in the water act on the flocculant, and the process of generating the micro-flocs is called agglomeration by compressing the electric double layer and electrically neutralizing the mechanism, etc., to lose or reduce the stability. The process of agglomerating micro-flocs under the agitation of bridging materials and water flow, and growing into large flocs through adsorption bridges and sediment nets is called flocculation. Mixing, coagulation, and flocculation are collectively referred to as coagulation, and the mixing process is typically accomplished in a mixing tank where agglomeration and flocculation are carried out.