As a commonly used inorganic polymer coagulant, polyaluminium chloride (PAC) plays an important role in the field of sewage treatment. The aluminium hydroxide colloid produced by its hydrolysis can effectively adsorb and remove suspended solids, colloidal substances and some soluble organic matter in water, thereby improving water quality. However, in practical applications, the amount of PAC added is not the more the better. Excessive addition of PAC will not only increase the treatment cost, but also may cause a series of problems such as turbidity rebound. Today, Yisheng Company will analyze the turbidity rebound problem caused by excessive addition of polyaluminium chloride in depth.
Reasons for turbidity rebound caused by polyaluminium chloride PAC:
Formation of new balance of colloid particles: When the amount of polyaluminium chloride PAC is appropriate, the aluminium hydroxide colloid produced by its hydrolysis can effectively break the stable state of sewage, adsorb colloidal particles to form alum flowers and settle. However, excessive addition of PAC will cause the colloidal particles in the water to re-form a stable state and form a new balance, making it impossible for the colloidal particles to settle effectively, resulting in turbid water.
pH value decrease: Excessive addition of polyaluminium chloride (PAC) will cause the pH value of sewage to decrease, affecting the effluent and flocculation effects. The decrease in pH value may destroy the stability of colloidal particles, causing them to redisperse in the water, thereby causing turbidity rebound.
Salinity increase: Excessive addition of polyaluminium chloride (PAC) will increase the salinity in the water, change the density of the solution, and prevent the flocculants from sinking. This not only affects the water purification effect, but may also have an adverse effect on subsequent treatment processes.
Iron residue: Some polyaluminium chloride (PAC) products may contain a certain amount of iron. Excessive addition of PAC will cause iron to remain in the water, causing the water to turn yellow, further affecting the clarity of the water.
Countermeasures for turbidity rebound caused by polyaluminium chloride:
Adjust the dosage of PAC: According to the water quality test results and the performance characteristics of PAC, reasonably adjust the dosage of PAC. Determine the optimal dosage through small tests and machine tests to avoid excessive dosage.
Strengthen water quality monitoring: Regularly monitor the water quality before and after treatment, including turbidity, pH value, dissolved oxygen and other indicators. Once problems such as turbidity rebound are found, take timely measures to adjust.
Optimize coagulation process: Combined with actual conditions, optimize coagulation process parameters, such as stirring intensity, stirring time, etc., to improve the coagulation effect and reduce the possibility of turbidity rebound.
Use decolorizer: For the yellowing problem of water caused by residual iron, decolorizer can be used for decolorization to improve the clarity of water quality.
Strengthen equipment maintenance: Regularly inspect and maintain sewage treatment equipment to ensure the normal operation of the equipment. Avoid problems such as uneven or excessive addition of polyaluminium chloride PAC due to equipment failure.
In summary, the turbidity rebound problem caused by excessive PAC addition cannot be ignored. To ensure the sewage treatment effect, the PAC dosage should be reasonably adjusted, water quality monitoring should be strengthened, coagulation process should be optimized, decolorizing agents should be used, and equipment maintenance should be strengthened. If you encounter any other problems during use, please feel free to contact us. We will arrange professional technicians to communicate with you to assist you in solving the problem and provide you with free testing, selection, sample and other services.
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
