Study On Ship Ash-water Treatment And Membrane Surface Modify Using MBR

With the continuous development of shipping trade, inevitably, ship sewage is beingdischarged into marine environment directly or indirectly. It not only does great harm to localmarine eco-environment but also to local social economic and public health..At the same time,the promulgating of IMO-VI puts forwards higher requirement for ship operability dischargestandard and adds more difficulty for ship sewage treatment. As the technological processesof Membrane bio-reactor that used in sewage treatment has many advantages itself, it issuitable for the treatment of ship sewage. This article is directed against the hot point problemthat how to control membrane fouling in Membrane bio-reactor and aims to improveanti-contamination ability of Membrane module by using Fe（OH）3coating. Several aspectsare mainly studies as below.（1）Observe the effects of Fe（OH）₃coating consistency, coating time and rotate speedof pump on pure water flux of modified membrane by doing orthogonal test. Research showsthat the best coat time is6hours, the best coat consistency of Fe（OH）3is0.15%and the bestrotate speed of pump is150r/min.（2） Do analysis on characteristics of membrane coated by Fe（OH）3, the scanningelectron microscope shows that there is an uniform adhesive layer on the membrane modulewhich is having being coated. The smooth surface of membrane becomes unsmooth at thesame time. Energy spectrum analysis shows that the surface of membrane is composed byC,O,F and Fe elements and the adhesive layer is iron compounds.（3）Do contrast experiment of continues flow on MBR which is not being modified.Observe the pollutants removal efficiency and running period of modified MBR. Researchshows that these two groups of MBR have the same pollutants removal efficiency to CODCr,ammonia nitrogen and phosphorus. Both of which can reach to the primary standard ofdomestic sewage discharging. But the running period of MBR being modified is much longerthan MBR not being modified obviously.（4）Cleans the membrane using the technology of ultrasonic cleaning, observe theeffects of cleaning time, distance between vibrating board and membrane being cleaned,ultrasonic cleaning power and aeration rate when using ultrasonic-aeration combined cleaning on membrane cleaning efficiency. Research shows that the best ultrasonic cleaning parametersare as below, ultrasonic time15min, ultrasonic distance5cm, ultrasonic power200W. Observethe surface of the membrane both before and after ultrasonic through the scanning electronmicroscope, the results showed that the surface of membrane irreversible damaged easilywhen using excess ultrasonic which will does harm to the service life of membrane module.