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In order to reduce the energy consumption and membrane fouling of the conventional membrane bioreactor (MBR), a kind of low energy consumption vortex wave flow MBR was exploited based on the combination of biofilm process and membrane filtration process, as well as the vortex wave flow technique. The experimental results showed that the vortex wave flow state in the membrane module could be formed when the Reynolds number (Re) of liquid was adjusted between 450 and 1,050, and the membrane flux declined more slowly in the vortex wave flow state than those in the laminar flow state and turbulent flow state. The MBR system was used to treat domestic wastewater under the condition of vortex wave flow state for 30 days. The results showed that the removal efficiency for CODcr and NH3-N was 82% and 98% respectively, and the permeate quality met the requirement of 'Water quality standard for urban miscellaneous water consumption (GB/T 18920-2002)'. Analysis of the energy consumption of the MBR showed that the average energy consumption was 1.90±0.55 kWh/m³ (permeate), which was only two thirds of conventional MBR energy consumption. [ABSTRACT FROM AUTHOR]

The effects of drying method on the sugar conversion of corn stover during dilute sulfuric acid pretreatment were studied. Oven-dried corn stover (ODCS) was more sensitive to temperature and time during dilute sulfuric acid pretreatment than air-dried corn stover (ADCS). The yield of the total reducing sugar reached 43.9% when ODCS was pretreated for 50 min at 120°C, which was even higher than the value of the ADCS treated for 90 min. The glucose yield of ODCS was 1.6- to 1.9-fold higher than ADCS. These results indicate that rapidly losing water is a better drying method compared to air drying. [ABSTRACT FROM AUTHOR]

Corn stover silage is an attractive raw material for the production of biofuels and chemicals due to its high content of carbohydrates and easy degradability. The effects of Fe(NO) pretreatment conditions on sugar yields were investigated for corn stover silage. In addition, a combined severity factor was used to evaluate the effect of pretreatment conditions on the concentration of total sugars and inhibitors. Optimum pretreatment condition was obtained at 150 °C for 10 min with 0.05 M Fe(NO), at which the yields of soluble xylose and glucose in liquid achieved 91.80% of initial xylose, 96.74% of initial arabinose and 19.09% of initial glucose, respectively, meanwhile, 91.84% of initial xylose, 98.24% of initial arabinose, and 19.91% of initial glucose were removed. In addition, a severity analysis showed that the maximum sugar concentration of 33.48 g/l was achieved at combined severity parameter value of 0.62, while the inhibitor concentration was only 0.03 g/l. Fe(NO) is an effective catalyst to enhance hemicellulose hydrolysis in corn stover silage, the yields of monomeric xylose in the liquid fraction reached as high as 91.06% of initial xylose and 96.22% of initial arabinose, respectively. [ABSTRACT FROM AUTHOR]