In the process of treating industrial wastewater and domestic sewage, polyaluminium chloride plays a vital role as a water treatment coagulant. However, in practical applications, sometimes we encounter the problem of large particles of alum flocs rising on the surface of the sedimentation tank, which not only affects the efficiency of water quality treatment, but also may have an adverse effect on the subsequent treatment process. Today, Henan Xinhuan Company will discuss with you the reasons for the rise of alum flocs on the surface of the sedimentation tank in polyaluminium chloride treatment.
Reasons for the rise of alum flocs after adding polyaluminium chloride PAC:
Too small dosage: the alum flocs formed are loose, and the suspended matter fails to be effectively separated and precipitated, which may cause the alum flocs to float.
Too large dosage: counter-ion phenomenon is generated, which makes it difficult for the alum flocs to condense, and the floating phenomenon will also occur.
Water temperature changes: Sudden changes in air temperature or water temperature may cause changes in water flow, which in turn affects the stability of the alum flocs and causes them to float.
Too fast stirring speed: Too fast stirring speed may break up the alum flocs that have been formed, causing them to float to the water surface.
Process flow problems: If there are problems with the polyaluminium chloride treatment process, such as the inability of activated sludge to return, it may cause the alum flocs to float along the pool wall.
Untimely sludge discharge or too high sludge layer: A high sludge layer or untimely sludge discharge may cause alum flowers to float.
Types of polyaluminium chloride: In sewage treatment, high-content and spray-type polyaluminium chloride are more likely to cause alum flowers to float.
Solution to the problem of alum flocs rising after adding polyaluminium chloride PAC:
Adjust the dosage of coagulant: According to the water quality and treatment requirements, appropriately increase or decrease the dosage of polyaluminium chloride PAC. If the dosage is too small, the dosage should be gradually increased until the best effect is achieved; if the dosage is too large, the dosage should be appropriately reduced to avoid the occurrence of counter-ion phenomenon.
Control water temperature and water flow rate: When changing seasons or when the temperature changes suddenly, make preparations in advance to control the stability of water temperature and water flow rate. Consider using heating or cooling equipment to maintain the stability of water temperature.
Adjust stirring speed: Control the speed of the mixer to avoid breaking the alum flocs too fast. Generally speaking, the stirring speed should not be greater than 200 rpm. If the alum flocs have been broken, polyaluminium chloride PAC can be added as appropriate for re-flocculation.
Check and optimize the process flow: Check the process flow regularly to ensure that the activated sludge can flow back normally. If problems are found in the process flow, they should be repaired and optimized in time.
Discharge sludge and adjust the height of the sludge layer in time: Discharge sludge regularly to avoid the sludge layer being too high. Adjust the sludge discharge cycle and time according to the actual situation.
Change the type of polyaluminium chloride: If the use of high-content or spray-type polyaluminium chloride causes the alum flocs to float, you can consider replacing it with industrial-grade polyaluminium chloride or flocculant products with high iron content.
In summary, solving the problem of large alum flocs rising on the surface of the sedimentation tank during polyaluminium chloride treatment requires multiple aspects. Through the comprehensive application of these measures, the problem of alum flocs floating can be effectively solved and the water quality treatment effect can be improved.
The main products of flocculant manufacturer Xinhuan Water Treatment are:
White polyaluminium chloride (food grade), drinking grade polyaluminium chloride, industrial grade polyaluminium chloride, anionic polyacrylamide, cationic polyacrylamide, nonionic polyacrylamide, petroleum recycling polyacrylamide, oil recovery polyacrylamide, polyacrylamide, polymer flocculant polymer flocculation coagulant, polymeric ferrous sulphate, polyferric aluminium chloride and other water treatment chemicals. Welcome customers to write to us to negotiate business! Tel/WhatsApp：+8619003830067 Email：joanna@xhwtm.com Contact:Joanna
