Polyacrylamide applications in different water treatment

Release time:

Jan 17,2024

The main function of polyacrylamide is as a flocculant. In water treatment, by adding an appropriate amount of polyacrylamide, tiny particles suspended in the water can be caused to aggregate into larger flocs, thereby facilitating sedimentation and filtration. This flocculation can effectively remove suspended solids, turbidity and organic matter, and improve the water purification effect. The application of polyacrylamide in water treatment can improve water quality and meet the needs of environmental protection and human health. In addition, polyacrylamide also has excellent adsorption capacity and can be used as an adsorbent to remove harmful substances in wastewater. It can also be used as an oil-displacing agent in oil field development.

Currently, polyacrylamide is the most widely used and most efficient polymer organic synthetic water treatment agent in the world. Let’s briefly talk about some of the uses of polyacrylamide in water treatment:

1. Application of polyacrylamide in water supply treatment

The purpose of water supply treatment is to remove impurities in the water through appropriate treatment and purification methods to meet the standards of domestic or industrial water. The application of polyacrylamide in water supply treatment mainly includes the treatment of low turbidity water and high turbidity water.

Research and experiments have shown that when using aluminum sulfate to treat low turbidity water, adding polyacrylamide at the same time can improve the water treatment capacity. When the concentration of aluminum sulfate is 3mg/L~9mg/L and the concentration of polyacrylamide is 0.0008mg/L When ~0.0125mg/L, the treated water turbidity is lower than 3 degrees. During the research, it was found that adding polymerized aluminum and polyacrylamide at the same time when treating low turbidity water can significantly improve the turbidity removal effect. In the experiment, when the concentration of polyacrylamide added is 0.03 mg/L, the settling time can be shortened to half that of when polymerized aluminum is used alone, and the amount of polymerized aluminum can be reduced by 22%. Studies have shown that when treating the Yellow River water with high turbidity, adding polyaluminum chloride and polyacrylamide at the same time can save costs and improve the quality of the effluent. At present, most water plants in my country add polyacrylamide when producing drinking water from high turbidity water.

2. Application of polyacrylamide in domestic sewage treatment

The main pollutants of urban domestic sewage are organic matter, which is eutrophic, and there are also pathogenic bacteria and inorganic salts. It is characterized by relatively high chemical oxygen demand (COD), turbidity, total phosphorus (TP), and total nitrogen (TN). The water is dark in color and smelly. For water bodies with complex components, single-component flocculants often fail to meet the requirements of water treatment, so composite flocculants have become the focus of research. Composite flocculants not only retain their respective advantages, but also make up for the shortcomings of single use and play a role in synergistic flocculation. There are three types of composite flocculants: organic, inorganic and organic-inorganic composite flocculants. The most commonly used is organic-inorganic composite flocculant. First, inorganic flocculants are added to the sewage for preliminary treatment, and then organic polymer flocculants such as polyacrylamide are added to further promote flocculation through their adsorption and bridging effect.

Studies have shown that when flocculating urban domestic sewage, the simultaneous use of liquid polyaluminum ferric chloride and polyacrylamide as coagulants and filter aids can increase the total phosphorus removal rate by 14.51%, from 75.61% to 90.12%. . Polyaluminum ferric chloride was also used as the coagulant, and at the same time, together with the coagulant polyacrylamide, the simulated urban polluted river water was treated by pneumatic flocculation, and good treatment results were achieved. Of course, polyacrylamide can also be modified to obtain modified derivatives that can be used alone to treat domestic sewage. The attapulgite composite polyacrylamide flocculant was made by in-situ polymerization of thermally modified attapulgite and acrylamide, which was used to treat polluted river water. Finally, it removed 66.3% of turbidity and 45.6% of COD.

3. Application of polyacrylamide in other industrial wastewater treatment

There are many types of other industrial wastewater with different properties and components. Individual conditions need to be analyzed individually and different polyacrylamides should be selected according to needs. The application of water-dispersed cationic polyacrylamide in papermaking wastewater treatment was studied. The test results show that the effect is better when the water-dispersed cationic polyacrylamide is used in combination with inorganic polyaluminum chloride, and when the two are used together When the dosage is 50 and 600 mg/L respectively, the treatment effect is the best, and the removal rates of suspended solids and chemical oxygen demand are 96.8% and 87.5% respectively. In the field of pharmaceutical wastewater, polyacrylamide is used as a coagulant and polymeric ferric sulfate is used as a flocculant to treat high-concentration xanthate production wastewater. The final result is a chemical oxygen demand removal rate of 84% and a xanthate removal rate of 100 %. In the dairy industry, due to the relatively high content of protein, sugar and fat in wastewater, the chemical oxygen demand COD is very high. The use of aluminum sulfate-polyacrylamide compound to treat dairy production wastewater has achieved good results. No matter how the chemical oxygen demand and biological oxygen demand of the raw water sample change, the removal rates are 62%~68% and 62% respectively. Between %~72%.

Polyacrylamide has a variety of functions and uses. When choosing polyacrylamide, the most important thing is to select a suitable polyacrylamide model and polyacrylamide with stable quality. Guangdong Shouxin Environmental Protection Materials Technology Co., Ltd. is a global brand of polyacrylamide with stable quality. We have developed more than 100 product models that are required by end customers in various industries, which can provide customers with more accurate selections. In addition, Capital Xin implements strict supervision from the control of raw materials, research and development of formulas, and double supervision and inspection when entering and exiting the warehouse, and has no concerns about the production cost of the manufacturer. It always chooses products with stable quality and qualified to leave the warehouse, so it is more able to Ensure product stability.