The important role of polyacrylamide in water treatment
1. Adsorption bridge: PAM molecular chains are fixed on different particle surfaces, and a bridge of polymer is formed between the particles, so that the particles form aggregates and settle.
2. Surface adsorption: various adsorption of polar group particles on PAM molecules.
3. Enhancement: PAM molecular chain and dispersed phase implicate the dispersed phase through various mechanical, physical, chemical and other effects to form a network, thereby playing an enhanced role.
These principles of action are the most fundamental reasons why the flocculant polyacrylamide can exert excellent water treatment effect.
PAM is the abbreviation of polyacrylamide with extremely high molecular flocculant, which is commonly used in sludge dewatering, sewage flocculation, decolorization, turbidity removal, filtration aid, thickening and other purposes. The molecular weight of PAM flocculant is between 5 million and 25 million, and the commonly used models are divided into three types: cationic, anionic, and non-ionic. Many customers have encountered the poor flocculation effect of adding polyacrylamide during sewage treatment, and today we in Shaanxi Botaida will briefly talk about the reasons that affect the flocculation effect of PAM.
PAM flocculant is most commonly used in sewage treatment, adding a small amount of polyacrylamide solution to sewage can show strong flocculation function, but sometimes there will be poor flocculation effect, this reason can be basically divided into three categories:
1. The PAM model is selected incorrectly, and cationic polyacrylamide is suitable for sewage flocculation treatment and organic sludge dewatering process with high toxicity and organic substances when it is used as sewage flocculation. Anionic PAM is suitable for flocculation treatment of suspended particles with large particles, high turbidity, and positive charge sewage, and nonionic polyacrylamide can reflect strong flocculation function in acidic water quality due to the activity of acylamino on the side chain of non-ionic functional group molecules.
2. The proportion of PAM polyacrylamide when dissolved, the dissolution ratio of anionic PAM and non-ionic polyacrylamide is one thousandth, and the optimal dissolution ratio of cationic polyacrylamide is two thousandths.
3, dissolved water temperature, PAM for white crystal particles, use need to be dissolved with clean tap water, the general dissolution time is 60 minutes, but the autumn and winter dissolution time will increase generally in about 2 hours, if the dissolved water temperature can shorten the dissolution time, the general temperature is controlled below 60 °C, it is recommended to be between 40-50 °C.
4, dosage, dosage is generally according to the water quality of different dosage will be different, in the sewage dosage less can not achieve the flocculation effect, the dosage will appear liquid viscosity occurs, generally before the use of the machine is recommended to do beaker flocculation experiment.