Composite membrane for mabr and preparation method thereof

Abstract

The present invention relates to the technical field of MABR composite membranes, in particular to a composite membrane for MABR and a preparation method thereof, including composite hollow fiber membranes and multi-dimensional holes arranged on the composite hollow fiber membranes, and the preparation method thereof comprises the following steps: polyvinylidene fluoride The diluent of 5% mass ratio of ethylene raw material and polyvinylidene fluoride raw material is placed in the reactor and melted at a high temperature at the same time; silk; under the traction of the take-up wheel, the spun film silk enters the extraction solution of 70% mass ratio of the polyvinylidene fluoride raw material for extraction, and the phenomenon of phase separation occurs during cooling to form holes, and the composite film for MABR is obtained. Throughout the experiment, by controlling the content of polyvinylidene fluoride, types of diluent and extractant, heating and standing temperature, winding rate and cooling temperature, etc., the properties of hollow fiber membrane surface pore morphology and membrane wall thickness were controlled.

Description

technical field [0001] The invention relates to the technical field of MABR composite membranes, in particular to a composite membrane for MABR and a preparation method thereof. Background technique [0002] Membrane-aerated biofilm reactor (membrane-aerated biofilmreactor, MABR) is the product of the combination of membrane technology and biofilm technology. This technology supplies oxygen through a gas-permeable membrane. Oxygen enters the outside of the lumen through the micropores on the membrane wall to achieve bubble-free aeration. The mass transfer efficiency of bubble-free aeration is high, and the oxygen utilization rate can be close to 100%, which is 5 to 7 times that of traditional aeration. [0003] The membrane material of MABR can be used as a carrier, and a microbial film can be formed on the surface of the membrane. The oxygen from the inside of the membrane lumen diffuses from the inside of the biofilm to the outside, and the substrate from the sewage diffu...

AI Technical Summary

Problems solved by technology

[0004] Membrane materials suitable for membrane aerated biofilm reactors can be roughly divided according to their surface properties and structures: hydrophobic microporous membranes and dense non-porous silica gel membranes. Among them, hydrophobic microporous membranes have the following disadvantages: (1) Due to its low bubble point pressure, the transfer of gas through the membrane pores can easily destroy the biofilm layer formed on the membrane surface; (2) During the growth of the biofilm, some biological debris from cells shed will adhere to the membrane surface, and even further block the pores on the surface, resulting in an increase in the gas mass transfer resistance of the membrane, a decrease in the gas flux, and finally the growth of the biofilm is affected due to insufficient oxygen supply; (3) some proteins and biological debris will make The hydrophobic performance of the membrane surface decreases and the liquid enters the membrane, so this membrane is not suitable for long-term operation

Although the dense non-porous silica membrane has certain advantages in bubble point pressure and pollution prevention, its low oxygen flux limits its application in MABR.

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