Study On The Method Of Synergistic Treatment Of Saline-Alkall Water Based On Electric Field And Electrospinning Membrane

Freshwater resources have become one of the important factors affecting the sustainable development of the global economy and society.Aiming at the problem of saline-alkali water desalination,this paper proposes a method based on electric field and electrospun membrane for the treatment of saline-alkali water desalination.Aiming at the permeability of membrane distillation membrane,based on the adjustment of solution parameters and spinning parameters,polymer nano-hydrophobic films with different physical structure characteristics were prepared,and hydrophobicity and flux characteristics were studied.Experiments show that the polymer film prepared at a solution concentration of 14wt%,a solvent ratio of 7/3,a voltage of 16kV and spinning for 90 minutes has a contact angle of 1 35.74°and a membrane flux of 0.74kg·h-1·m-2.Investigate the influence of the electric field on the membrane distillation process under the electrode type,polarity and voltage.It is believed that the external electric field promotes membrane flux.Multi-needle electrode,the membrane flux can be increased by 20.83%under the voltage of 5kV to 13kV;under the same voltage,the membrane flux of the single-needle negative polarity is increased by 26%than that of the positive polarity excitation;the multi-needle electrode is 51%higher than the single-needle electrode.Based on electric field simulation,the electric field distribution characteristics on both sides of the film are studied.The study found that under the needle electrode,the film surface electric field is normally distributed along the radius;under the multi-needle electrode,the film surface electric field mode is 1.614 times that of a single needle.Based on the calculation of the dissociation energy of water molecules,the dominant mechanism process of electric field assisted membrane distillation is discussed.The results show that the depolymerization of water molecular clusters under electric field excitation is the dominant mechanism process of electric field-assisted distillation;when the electric field on the membrane surface reaches 61×104V/m,the above-mentioned molecules depolymerize significantly;the electric field energy density under the multi-pin electrode is single 1.759 times under the needle electrode,which is more conducive to the increase of membrane flux.The research in this paper shows that the direct current electric field under the needle plate electrode can significantly promote the depolymerization of the electrospun membrane,indicating that the clusters of water molecules are depolymerized,thereby improving the saline-alkali water evolution efficiency of the polymer electrospun membrane.The research conclusions of this paper have certain guiding value for improving the efficiency of saline-alkali water desalination treatment.