Polyacrylamide use features a) flocculation: PAM suspended material can call in and through, bridging adsorption, flocculation effect. 2) adhesion: through mechanical, physical, chemical action, from the bonding effect. 3) reduction in resistance: PAM can effectively reduce the fluid friction, water trace PAM can drop 50-80%. 4) Thickening: PAM in neutral and acid conditions are thickening effect, when the PH value of 10 or more easily hydrolyzed PAM. Semi-mesh structure, thickening more apparent.