First, the dissolution of PAM: powder PAM is added to water and will be produced immediately; Second, the dissolution and stirring conditions: the dissolving tank is preferably cylindrical type, and the liquid level in the cylinder; Third, the dissolution concentration of PAM: powder PAM generally uses a content of 0; Fourth, precautions: As mentioned earlier, PAM has almost no toxicity, part; PAM powder products if unopened exposed to air, more than one year quality; Automobile painting wastewater is treated with polyacrylamide, automobile painting wastewater treatment; The disadvantage of inorganic flocculants is that the amount of sludge produced is large, and a small amount is used; It is understood that the dissolution of steam First, the dissolution of PAM: powder PAM added to water, will immediately produce swelling, if a large amount is too much, it will agglomerate, forming the so-called "longan, fish eye", not only difficult to dissolve, but also often cause the blockage of the dosing pump; Secondly, too fine PAM powder, when put into the dissolving tank, because of its lightness, it is easy to fly in the air, resulting in pollution of the working environment. The correct dissolution method, usually in the case of stirring, a small amount of continuous quantitative addition to the water, using one side of the spread and the other side of the dissolution method, which can effectively avoid the "fish eye" type insoluble matter, and effectively shorten the dissolution time. Second, dissolution and stirring conditions: the dissolving tank is preferably cylindrical, and the liquid level height in the cylinder is about 1.2-1.5 times of the cylinder diameter is the ideal liquid level. The four corners of the square cylinder are easy to produce dead angles due to the turbulence effect, and in order to avoid the accumulation of dead angles of undissolved particles, they should be avoided as much as possible. The mixer can be vertical or horizontal. Third, the dissolution concentration of PAM: powder PAM generally uses an aqueous solution with a content of 0.05-10%, and the specific concentration must be determined according to the specific characteristics of sludge. 4. Precautions: As mentioned earlier, PAM has almost no toxicity, and some hydrolysates may be irritating. During the operation, the inhalation of PAM powder and the adhesion of dissolved liquid to the eyes and nose should be avoided as much as possible, and once it occurs, it should be immediately rinsed repeatedly with a large amount of running water. When dissolving operations, it is best to wear protective equipment such as goggles and rubber gloves. Around the site, where the dissolved liquid is splashed, because sticky and slippery will be more dangerous, try to rinse with clean water and keep it dry. If the PAM powder product is not opened and exposed to the air, the quality will not change for more than one year, but because the product has strong hygroscopicity, it must be sealed and stored after opening, and may be preferred. The storage period of liquid products is short, glue PAM is generally within 6 months, latex PAM is generally 3-6 months, stirring slightly before use, 1% PAM solution should not be stored for more than 1 month. PAM should be stored in a dry, ventilated dark place at a temperature not exceeding 400C. When loading, unloading and transporting glue and latex products, try to avoid contact between PAM and iron and copper metals, and diaphragm pumps and piston pumps are preferred. Automobile painting wastewater is treated with polyacrylamide, and the effluent water quality indicators in automobile painting wastewater treatment projects are normal, but the amount of sludge generated is too large, and the reason is not known. The flocculant is aluminum sulfate, and the pH value is adjusted with sodium hydroxide. The disadvantage of inorganic flocculants is that the amount of sludge produced is large, and a small amount of polyacrylamide is used as a coagulant. If the organic cationic coagulant, the amount added is one of 1/10 of the inorganic coagulant, the amount of sludge produced should be reduced, it is recommended not to use polyaluminum, it is better to use polyferric sulfate, and it must use PAM. It is understood that the painting of automobiles and their parts is one of the links that produces the most wastewater discharge in the automobile manufacturing process. Automobile painting wastewater contains resin, surfactants, heavy metal ions, Oil, pigments and other pollutants, especially the electrophoretic wastewater and painting wastewater have complex components, high concentration and poor biochemistry. For this type of wastewater, the traditional method is to directly coagulate the mixed wastewater, the treatment effect is not ideal, the effluent quality is unstable, and it is difficult to meet the discharge standards. In particular, the spray painting wastewater contains a large amount of organic solvents dissolved in water, and the direct treatment effect of coagulation method is very poor. According to the characteristics of coating wastewater, the two-step treatment method of pretreatment and subsequent treatment was adopted, and the Fenton oxidation-coagulation precipitation and air flotation physicochemical process were selected to meet the emission standard, and the CODCr removal rate reached more than 80%. The treatment of coating wastewater by separating treatment, coagulation precipitation, coagulation air flotation, sand filtration and other processes will generally achieve good results. Among them, for the electrophoresis waste liquid of coating wastewater, the cathodic electrophoresis wastewater contains a large number of polymer organic matter, CODCr up to 20000mg/L, and also contains a large amount of electrophoresis residue, which is a fine suspended solids or negative colloidal in water. Appropriate cationic polyacrylamide (PAM) and polyaluminum chloride (PAC) are added as coagulants in the treatment, and the adsorption bridging effect of the flocculant is used to quickly remove pollutants in wastewater. The pH value of the electrophoresis waste liquid is required to be between 11~12 during pretreatment, which has a good precipitation effect. The CODCr of the reacted effluent was about 2000 mg/L. Recently, many customers have consulted whether they can directly use polyacrylamide or polyaluminum chloride to purify their own well water, the following by polyacrylamide direct manufacturer professionals after testing to tell you the answer, the answer concluded: whether polyacrylamide or polyaluminum chloride is not feasible this method. Although it is said on the Internet that water companies use polyaluminum chloride and water companies use polyacrylamide, these are for water companies. The water treatment of the water company is to first add polyacrylamide or polyaluminum chloride to the water for reaction, and then put it into the sedimentation tank for precipitation, and then filter, if filtered, more quartz sand or activated carbon is used, and finally the water is supplied to each household through the pipeline.