Do you know why caking occurs in polyaluminum chloride (PAC) before and after its use?

　　When we use polyaluminum chloride (PAC), it typically appears as a powdered or flake-like granular substance that dissolves easily and rapidly induces flocculation of suspended solids in wastewater. If it forms lumps, the effectiveness of PAC will be severely compromised.

　　Causes of caking in polyaluminum chloride (PAC) before use:

　　1.Polyaluminum chloride may directly cake before use, primarily due to being soaked by rainwater or caking caused by moisture. If the caking is not severe, it can be placed in the sun to allow the internal moisture to evaporate and dry, after which it can be ground into powder and reused. If the caking is severe, it is advisable not to continue using it, as this may lead to the formation of insoluble substances.

　　2.Another issue is the normal extrusion and agglomeration of polyaluminum chloride (PAC) during transportation. During the production process of PAC, some moisture may not fully evaporate before packaging, leading to caking during extrusion. This type of caking is normal and can be completely dissolved by directly adding it to water for use. It should be noted that if the caked lumps are relatively large, they can be broken into smaller pieces by tapping before use.

　　Causes of caking during the use of polyaluminum chloride (PAC):

　　1.Polyaluminum chloride (PAC) dissolves slowly and has high viscosity. If it is added too quickly or unevenly during dissolution, or if an excessive amount of dry powder is introduced during preparation without sufficient time to dissolve, it may result in incomplete dissolution and subsequent caking of the PAC.

　　If the dosing rate is too fast and polyaluminum chloride (PAC) is added too rapidly, it can lead to the formation of a gelatinous, mucus-like mass. Simply pouring it into a bucket and adding water will cause it to solidify into plastic-like lumps resembling waste material.

　　The water used to prepare the polyaluminum chloride (PAC) solution is unclean and contains suspended solids and impurities, which can cause caking in the solution.

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