When it comes to sewage treatment agents, polyaluminium chloride must be mentioned first. Why can it become the main force in sewage treatment? The pH range of polyaluminium chloride is much wider than that of traditional aluminium salts. Generally, in low-temperature water (<5°C), the coagulation and turbidity removal efficiency of traditional coagulants is significantly reduced and the water quality of the effluent is deteriorated. However, the use of polyaluminium can achieve better coagulation and turbidity removal effects regardless of low or normal temperature water. In addition, polyaluminium chloride can significantly improve the efficiency of solid-liquid separation, improve sedimentation filtration and sludge dewatering functions, thereby shortening the residence time of the sedimentation tank and increasing the water output. In addition, because the generated floccules are large and compact, they are easy to filter and dewater. The residual aluminium content in the water after aluminium chloride treatment is very low. The residual aluminium content in the water treated with traditional aluminium sulfate is generally 150~255μg/L, while the residual aluminium content in the water treated with polyaluminium is only 40~55μg/L.
In the actual application process, polyaluminium chloride not only has a strong coagulation and turbidity removal effect, but also has a significant decolorization and humus removal effect. Under the same treatment conditions, the dosage of polyaluminium is reduced by 2/3 compared with traditional aluminium salts to achieve the best flocculation effect. Under the same dosage conditions, the use of polyaluminium can achieve lower residual turbidity than traditional aluminium salts, so the same treatment results can be obtained with a lower dosage.
Henan Xinhuan Water Treatment Materials Co., Ltd. is a manufacturer engaged in the production of polyaluminum chloride flocculants for many years. After research, it was found that in order to make the water purification effect of polyaluminum chloride PAC good, it is necessary to understand its influencing factors, but the influence of water quality is one of them. The content of suspended particles has an impact on the flocculation and coagulation stages. When the dosage is too large, the charge of the colloid system will change and appear stable. The dosage of coagulant required for the precipitate is inversely proportional to the concentration of suspended particles, and it will not appear stable again. According to the alkalinity and suspended matter content in the water, it can be roughly divided into the following 4 types of treatment:
1. The suspended matter content is high and the alkalinity is low. After adding the coagulant, the system PH <7. At this time, the hydrolysis product is mainly positively charged, and coagulation can be completed through adsorption and electrical neutralization. The best PH value for aluminum should be between 6-7, and for iron between 5-7;
2. The suspended matter content and alkalinity are both high. When the alkalinity is high, so that the pH value still reaches 7.5 or above after adding the coagulant, the hydrolysis products of the coagulant are mainly negatively charged, and adsorption and electrical neutralization cannot be used to achieve coagulation. At this time, the precipitation net capture method is generally used, and sufficient coagulant needs to be added, or polyaluminum chloride can also be used to achieve better results;
3. The suspended matter content is low and the alkalinity is high. At this time, the hydrolysis products of the coagulant are mainly negatively charged, so the precipitation net capture method is used to achieve coagulation. The amount of coagulant added is inversely proportional to the suspended matter concentration. Therefore, coagulant aids are often added to increase the colloidal particle concentration of the raw water and reduce the amount of coagulant added accordingly;
4. The suspended matter content and alkalinity are both low. This is a more difficult situation to deal with. At this time, the coagulant can form a hydrolysis product with a positive charge, but because the suspended particle concentration is too low, there is little chance of collision and aggregation, and it is difficult to achieve effective coagulation. At this time, the method of adding alkalinity or suspended matter concentration to cause turbidity is often used to convert it into other types of water for treatment.
The above is the experience summarized by Xinhuan Company, a high-quality polyaluminium chloride manufacturer, after long-term research. Regarding the impact of purification on different water bodies, we hope that the vast majority of users will understand it. If you have any questions, you can contact us at any time.
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
