Preparation Of Hydrophobic And Controllable Cellulose-based Flocculation Material And Its Sludge Properties Evaluation

With the rapid development of Chinese industry,the pollution of our environment is becoming more and more serious,the discharge of industrial wastewater is the most serious.Flocculation method is a kind of method that it is widely used and enterprise in wastewater treatment,because it can effectively remove the suspended particles in wastewater,and both economic and simple operation,but it could produce a byproduct of sludge in the flocculation precipitation treated wastewater.At present,natural macromolecular flocculant is popular among scholars,because its wide range of raw materials,environmental protection,renewable and degradable.Because this kind of flocculant was strong hydrophilicity,water content was high of flocs formed when it treated wastewater,caused lots of sludge,increased the cost of sludge late shipping and handling,to the hydrophobic modification of flocculant is significant.In this study,used low cost and renewable bamboo cellulose as substrate material to prepare the cellulose based flocculant by free radical polymerization.In the synthesis process,used sodium hydroxide and urea system dissolved cellulose(cellulose concentration is 2%),ammonium persulfate initiated at 55 ?,added polyacrylamide reaction for 1.5 hours,finally anionic cellulose-based flocculant was prepared.The flocculant flocculated simulated wastewater kaolin solution,found its excellent flocculation performance,finally applied to industrial wastewater treatment,also showed good flocculation performance,but water content was high of flocs formed,resulted in large amount of sludge.In order to solve the problem that water content was high of flocs formed after flocculation,cellulose-based flocculant with 3-aminopropyltriethoxysilane coupling agent to prepare the hydrophobic and controllable cellulose-base flocculation material.First applied one of the four factors three levels orthogonal experiments to optimize the preparation of hydrophobic and controllable cellulose-base flocculation material,the preparation process conditions: the best solution pH = 9,the amount of APTES 0.2 g/g(relative to the quality of the cellulose),reaction time is 10 hours,reaction temperature at 70?.By infrared spectroscopy to verifiy the molecular structure of cellulose,thermogravimetric analysis to research its thermostability,scanning electron microscope to explore the morphology change of product.Finally the hydrophobic and controllable cellulose-base flocculation material applied to mechanical wastewater treatment,because the composition ofprinting and dyeing wastewater is more complex,so we adopted the coagulation of hydrophobic and controllable cellulose-base flocculation material and the coagulant PAC to treat dyeing wastewater,and through the experiment was discovered we found that the hydrophobic and controllable cellulose-based flocculant material had excellent properties and sludge flocculation performance,even better than that of the unmodified cellulose-base and business of anionic polyacrylamide flocculant.Studied the mechanism of sludge dewatering properties after the hydrophobic and controllable cellulose-based flocculation treated mechanical wastewater and dyeing wastewater by Zeta potential and sludge compression factor to verify the sludge dewatering mechanism.