The Study On Development And Performance Of New Membrane Bioreactors

As a kind of high efficient equipment of water treatment, membrane bioreactor has many advantages, such as good effluent quality, steady operation, broad application scope, and it has a extensive application prospect in wastewater treatment and sewage reclamation. Therefore, it has important significance on prompt membrane bioreactor large-scale application to optimize membrane bioreactor design and operation and develop MBR equipment of low energy consumption, various function, and duration.By summarizing domestic and international research accomplishment on membrane bioreactor, optimum operation parameters and design parameters are found out in this paper. And two new kinds of MBR (biological hydrolysis MBR and pressurized MBR) are developed according to hydrolysis and pressurization dissolution principle. Through little examination, pilot study and actual project, influences on treatment effect of air-water rate, HRT, concentration of pollutant, operating pressure and temperature are researched; The law of membrane flux attenuation is studied, and corresponding measures reducing the fouling are tried, such as no- effluent aeration, air and water backflush, chemical cleaning; On the foundation of experiment and theoretical analysis, the composition of membrane fouling resistance is analyzed in this paper, Additionally the sludge properties of P-MBR is studied preliminarily. Experiment shows:1. Biological hydrolysis MBR has good effect in nitrogen removal When it is used to treat domestic wastewater of high ammonia-nitrogen in a housing estate, the NHj-N decrease from 85-115 mg/L of influent to less than 5 mg/L of effluent, and the removal rate of NHt-N is above 95%., and other effluent indexes meet the grey water standard of washing vehicle and cleaning (GJ25 .1-89).2. Biological h ydrolysis M BR h as good effect i n o rganism removal. W hen i t i s u sed t o t reat domestic wastewater of high concertration easy degradation organic wastewater (meal wastewater), COD and NHt-N of the influent are 2980 mg/L, and 17.26 mg/L, COD and NHrN of the effluent are 58.5 mg/L and 1.22 mg/L respectively, and the removal rates of COD and NHt-N reach 98% and 93%respectively; When it is used to treat refractory TNT water, by extra carbon source, concertration of TNT reduced from 70-80 mg/L to less than 0.5 mg/L, and the removal rate reach 92.9%.3. Pressurized MBR good efficiency in organism removal When it is used to treat the synthetic wastewater in which starch is the main pollutant, COD is reduced from 1545 mg/L to 20 mg/L, and the removal rate is 98.7%; The removal effect of organism is strengthened obviously after adding hydrolysis pretreatment. When COD of influent is 13,864 mg/L, COD of effluent only is 57.14 mg/L; When COD of influent is as high as 25,680 mg/L, volume load being 10.27 kgCOD/m3·d, the COD removal rate can be as high as 89.8%.4. The membrane of P-MBR fouling resistance was mainly completed of polarization layer resistance (Rp) and internal fouling resistance (/fy). Without hydrolysis pretrealment, polarization layer resistance (Rp) and internal fouling resistance (R$ take 36.1% and the 50% of total fouling resistance respectively, With hydrolysis pretreatment, polarization layer resistance (Rp) and internal fouling resistance (%) take 32.13% and the 44.94% of total fouling resistance respectively.