Flocculant polyacrylamide for sewage treatment
The flocculant polyacrylamide for sewage treatment is suitable for dewatering of urban sewage, urban sludge, papermaking sludge and other industrial sludge. Sand prevention and fixation: dissolve the non-ionic polyacrylamide into 0.3% concentration, add crosslinking agent, and spray it on the desert to prevent and fix sand. Soil humectant: used as the basic raw material of soil humectant and various modified polyacrylamide. Cationic polyacrylamide label: cationic polyacrylamide (CPAM) linear polymer, because it has a variety of active groups, which can form hydrogen bonds with many affinity and adsorption. The form of cationic polyacrylamide product: cationic polyacrylamide can be divided into two forms according to the different forms. Solid particles are widely used in the market.
Flocculant polyacrylamide for sewage treatment has certain toxicity
When the processing temperature is low, such as boiling with water, the water of acrylamide is quite low. Water content is also an important factor affecting the formation of acrylamide, which is higher when the water and surface temperature rise after baking and frying food; Except that it decreased in the later stage of baking. The main precursor of acrylamide is free aspartic acid (a representative acid in potatoes and cereals) and reducing sugar, which react to produce acrylamide. Comparison of acrylamide formed in food; Except that the acrylamide content increases with storage time. Acrylamide has mutagenic effects both in vitro and in vivo, and can cause mammalian somatic and cellular mutations and chromosomal abnormalities, such as micronucleus formation, sister chromatid exchange, polyploidy, aneuploidy and other filamentous abnormalities. The dominant lethal test is positive. It was proved that epoxy Propionamide, a metabolite of acrylamide, was its main mutagenic activity. Epidemiological investigation on the occupational population of acrylamide and the population accidentally exposed to acrylamide due to accidents. Cationic polyacrylamide emulsion as a new form of products is less applied in the market. The so-called hydrolysis degree of polyacrylamide refers to the ability of weak ions in polyacrylamide solution to combine with water to form weak alkali or weak acid, or the strength of weak acid and weak alkali in polyacrylamide aqueous solution. For strong acids and bases, the greater the ionization degree, the stronger the corresponding acidity and alkalinity, and the weaker the degree of hydrolysis. For some soluble polyacrylamide, the greater the ionization degree, the more ionized ions, and the weaker the degree of hydrolysis. Generally, the greater the ionization degree, the weaker the degree of hydrolysis. On the contrary, the smaller the ionization degree, the greater the degree of hydrolysis. Characteristics: good water solubility and can be dissolved in cold water. Cationic polyacrylamide can be greatly flocculated by adding a small amount of cationic polyacrylamide products. Generally, only 0.01 ~ 10ppm (0.01 ~ 10g / m3) needs to be added.
Flocculant polyacrylamide for sewage treatment is widely used in industry
At the same time, cationic polyacrylamide products and inorganic flocculants (polymeric iron, polyaluminium chloride, iron salt, etc.) can show greater effect. Precautions for the use of cationic polyacrylamide: the size of floc: too small floc will affect the drainage speed, and too large floc will restrict more water and mud. The molecular weight of polyacrylamide can the size of floc. Sludge characteristics. Point to understand the source, characteristics, composition and proportion of sludge. According to different properties, sludge can be divided into organic and inorganic sludge. The anionic type is mostly PAM water disintegration (HPAM). There are a large number of amide groups on the main chain of polyacrylamide with high chemical activity. It can be modified to prepare many polyacrylamide derivatives. The products have been widely used in papermaking, mineral processing, oil extraction, metallurgy, building materials, sewage treatment and other industries. Polyacrylamide is used as flocculant.
Application skills of flocculant polyacrylamide for sewage treatment
The molecular chain of high molecular weight polyacrylamide is very long, the long molecular chain must curl, and they must be entangled together. Therefore, the rapid dissolution of polyacrylamide depends on the rapid infiltration and attack of solvent water molecules, net hydrogen bond dissociation and molecular chain entanglement. The dissolution rate of polyacrylamide is related to its molecular weight, ionic degree, molecular geometry, dissolution temperature, stirring and feeding. The dissolution rate decreases with the increase of molecular weight and the degree of chemical crosslinking. The overall crosslinking will make polyacrylamide insoluble first. In powder manufacturing, high drying temperature and long drying time will make the product partially branched or slightly crosslinked, and the dissolution time will even appear partially insoluble. Due to the immature production process of some manufacturers, the dissolution speed is very slow and there are many insoluble substances after dissolution for a certain time. Dissolution temperature and stirring rate are conducive to molecular diffusion, while dissolution rate. However, higher dissolution temperature (above 50 ℃) and strong stirring rate will reduce the temperature of polyacrylamide. When the turbidity is high, the concentration is low, and when the turbidity is low, the concentration can be appropriately proportioned). The recommended concentration is 0.2-0.5%. Precautions for the use of polyacrylamide: when preparing polyacrylamide aqueous solution, it should be carried out in enamel, galvanized, aluminum or plastic barrels. It cannot be prepared and stored in iron containers. When dissolving, It should be noted that polyacrylamide products should be evenly and slowly added to the dissolver with stirring and heating measures.