Fabrication Of High Permeability Hollow Fiber Membrane Used In MABR

MABR (Membrane Aeration Biofilm Reactor) is a combined waste watertreatment technical, which combines traditional biofilm technology with membranetechnology, this has a good advantage in dealing with organic waste water andvolatile contaminants containing waste water. MABR membrane module is the coreof MABR process. The gas permeability and surface characteristics are directlyrelated to the performance of MABR wastewater treatment. So far there is nospecialized membrane for industrial MABR process, which constrained to thedevelopment of MABR industrial applications. MABR composite membrane isconsisted of a porous support layer with a good perviousness performance andfunction skin with excellent permselectivity. But all the production processes of thecomposite membrane are complex and expensive, and cannot keep a stableperformance, which is very easily to produce defects. In this paper, a simple methodfor preparing a composite porous polypropylene film with a biological affinity skinwhich suitable MABR process was developed. By melt-spun stretch method, a mixedgroup to prepare porous membrane discussed.After experiments, a porous membrane was prepared by melt-spun stretch (MS-S)method at appropriate condition, including a lower spinning temperature, a highermelt draw ratio and a suitable post processing method.A no-defect composite hollow fiber membrane was prepared through L-DOPAoxidation since its strong adhesion and film forming properties in alkaline aqueoussolution. The effects of L-DOPA concentrations, reaction time and pH value ofsolution in the modification were studied. The properties of modified membrane, suchas surface topography and membrane hydrophobicity before and after themodification were analyzed, respectively. The no-defect surface can be formed at theconcentration of1.5g/L (pH9.5) after7h reaction, with a gas flux of0.3176ml/(cm2s) and water contact angel of75.1°were achieved. The MABR tests indicate thatthe COD removals and bioadhesive properties of the modified membrane wereimproved efficiently.This paper explored the polypropylene/inorganic nanoparticle compositematerials to prepare hollow fiber membrane by melt spun stretching method. For the incompatibility between different materials, these composite hollow fiber membranesare with lacerate shaped porous, which ensure high porosity. After tests, with theincrease of the content of nanoparticles, gas flux increase, contact Angle andmechanical strength is slightly reduced. Polypropylene/nanoparticles can blendspinning.