Biopharmaceutical industry is a large pollutant, the discharge of waste water not only high concentration of organic pollutants, but also contains a variety of factors to inhibit microbial growth, the use of general wastewater treatment technology can achieve good treatment results. Biopharmaceutical industry is based on food as raw material, fermentation and culture of specific medicinal microorganisms, fermentation broth after filtration through the chemical method can be extracted. In the pharmaceutical process there are two main types of waste water: fermentation wastewater and wastewater extraction. Fermentation wastewater mixed with fermentation residues and microbial bacteria, suspended solids content of high, for some microbial have a strong inhibitory effect. Adding the coagulant can precipitate the suspended matter, the liquid on the inhibition of microbial significantly reduced. Extraction of waste water is the filtrate after chemical treatment of chemical ingredients.
In the case of polyacrylamide flocculants in the treatment of pharmaceutical wastewater, the cationic polyacrylamide product is generally selected if it is biochemical sludge treatment. If the organic concentration is high, even cationic polyacrylamide Ion degree of 60 or more the best results, if it is electrolytic treatment or the previous paragraph air handling situation. According to the water quality of the sewage, the most critical technical indicators are to see the size of the PH value to determine the choice of cationic polyacrylamide flocculant, the general principle of PH less than 7, then often use non-ionic polyacrylamide as coagulant or sludge Concentrated sinks.
Starch. If PH is 7 or more, the most commonly used is anionic polyacrylamide.
As far as I know polyacrylamide (PAM) is a water-soluble polymer, insoluble in most organic solvents, has good flocculation, can reduce the friction between the liquid resistance
PAM in water treatment mainly in two areas:
First, coagulation sedimentation, as coagulant
Second, the sludge dewatering, the sludge into a group, easy to dehydration.
PAM in the sewage treatment of the common process: wastewater pretreatment after coagulation treatment. Pretreatment processes typically include adsorption, filtration, and the like. Post-treatment process Depending on the nature of the sewage, can be used oxidation, biological treatment, air float and so on.
PH value of the wastewater treatment flocculation effect has a great impact.
1) can change the solid surface electrical and double layer thickness, thus affecting the PAM solid adsorption;
2) it can change the shape of the flocculant molecular chain. Under normal circumstances, NPAM for PH 1 to 6, APAM PH value of 6 to 10, CPAM PH value of 1 to 10.
The content of suspended solids in waste water will directly affect the amount of flocculant and flocculation effect. Over the General Assembly to allow the floss free settlement blocked, too small particles to reduce the chance of collision, affecting the floc formation. For wastewater with very low suspended solids, it may be desirable to increase the solid-liquid ratio by reflowing from the bottom of the sediment or by adding solid particles.
The effect of temperature on the flocculation effect of waste water is complicated. The temperature increases, the viscosity and density of the liquid decrease, which is favorable for the settlement of the floc. But the temperature is too high, will affect the adsorption of PAM particles in the surface.
PAM for the coagulant, generally with flocculant (master coagulant) PAC use.
PAC role is to sludge flocculation reaction, through the sedimentation network to form a granular suspension.
PAM for PAC, the role is to make the granular suspension of large alum, gathered into a larger floc, the formation of regional settlement. To achieve better SS removal effect.