Preparation Of Industrial-grade PSF And The Influence Factors Of The Flocs

Coagulation has been became the preferred technology in process of wastewater treatment because of simple operation,low price and high coagulation efficiencies. For the coagulant is the core of the coagulation process, develope an efficient,low price coagulant is the key to treat wastewater.Poly-silicic-ferric coagulant is a new type of polymer inorganic coagulant,the coagulation efficiency is better than traditional coagulants. In order to promote the industrial application of poly-silicic-ferric coagulant,adopt industrial-grade materials prepare is a low cost and easy application method. Due to the purity is low,the performance of the industrial-grade PSF is different from AR PSF.It is difficult to compliance just on biological treatment,as the acrylic wastewater contains many biodegradable substances.With wastewater discharge standard increasingly strict, it requires advanced method to treat this wastewater.In this paper,acrylic fiber wastewater as the research object,research on influence factors in the preparation process of the coagulant,and find the best preparation conditions;in order to make the effect optimal,considerring the effect of the reaction conditions at the time of acrylic fiber wastewater treatment and optimizing reaction conditions;research on industrial-grade PSF coagulation mechanism,and improve it performance,so as to provide a theoretical basis for the application of low-cost,high-performance coagulant.The main contents and results as following:With ferric sulfate,sodium silicate,sodium chlorate and sulphuric acid as industial materials,the industrial-grade PSF coagulant was prepared,the experiment apply response surface methodology to optimize the preparation conditions of the industrial-grade PSF coagulant,obtain the optimal conditions are:initial pH of the flocculation is 1.72, Fe-Si molar ratio is 1.31, the activation time is 1.05 h.Using scanning electron microscopy and transmission electron microscopy analysis concluded that, the industrial-grade PSF coagulant netted and sweeped to remove the contaminants from water for it has a smaller structure and uniform gap.Optimization reaction conditions on industrial-grade PSF coagulant treatment of acrylic wastewater using response surface methodology,obtaining the optimum reaction conditions are: pH value of 7.44, the dosage of 1.74 g / L, the settling time of 17.26 min.Under optimum conditions the CODcr removal rate is 54.12%, turbidity removal rate is92.39%,TN removal rate is 17%.Using the UV spectrophotometer and three-dimensional fluorescence scan the wastewater before and after treatment,we find that protein-like substances and UV humic substances are removed.Research on the change of the when using the industrial-grade PSF coagulant treat the acrylic wastewater,including the growth,crushing and recovery of the floc.Coagulant dosage and pH impact the growth of floc and the intensity factor of the floc,and it has charge neutralization and the trap swept volume under the best of coagulant dosage;the flocs large,dense and settling efficience under neutral conditions;the floc strength factor large at high dosage and under acidic conditions.The recovery ability related to the shearing time,the shearing time and the poorer recovery ability,so it is important to choose the right stirring time in the process of water treatment.