Papers by Keyword: Sequencing Batch Reactor (SBR)

Abstract: With influent distribution, high sludge concentration and low substrate state are carried out in ECOSUNIDE technics, bring in high nutrient removal efficiency. The “influent distribution” was introduced into conventional SBR for the treatment of municipal sewage, aiming to improve the nutrient removal efficiency. The whole process included an anaerobic and multiple anoxic/ aerobic units. The distribution ratios and modes are studied in this paper. The results show that the average sludge concentration reaches high to 6000mg/L. The influent mode has significant influences on the nutrient removal in the new SBR system. The mode of instantaneous influent in anaerobic stage and intermittent in frequent aeration stage is optimal, with the distribution ratio of 0.4/0.6, and the removal rates of NH3-N, TN and TP reach 99%, 87%, and 98%, respectively.

Abstract: This work aims to investigate the effects of carbon black (CB) and carbon nanotube (CNT) on mechanical properties and thermal behaviors of natural rubber (NR)/styrene butadiene rubber (SBR) blend at NR/SBR weight ratio of 80/20. CB loadings from 3-9 phr and CNT with 0.1-0.4 phr loadings were used as fillers in this study. The composites were prepared by latex compounding method. The specimens were examined for their tensile and dynamic mechanical properties and thermal stability using the universal testing machine, dynamic mechanical analyzer and thermal gravimetric analyzer, respectively. The tensile strength and modulus of the composites were improved as a result of the incorporation of CB and CNT. Dynamic mechanical analysis showed that the CB and CNT filled composites possessed high stiffness and low damping characteristics. Thermal stability of the composites was also proved to be better than the unfilled-rubber blend.

Abstract: In order to investigate low-temperature influence on the SBR process and sludge bulking, the SBR process pollutants removal effect was studied with normal and low temperature. The experimental results showed that the effluent water quality was better with temperature 22~24°C and DO 2mg/L. During this period, sludge bulking did not happen and the SVI was stable for 30d at the range of 60~80mL/g. The sludge settlement became worse when the temperature sharply dropped to 13~15°C and DO concentration was unchanged, the SVI was sharply increased to 240~270mL/g from 60~80mL/g in several cycles, and it was in the state of sludge bulking for 60d. The system denitrification effect was almost lost and the nitrification effect had been seriously affected. When the temperature returned to normal, the nitrification effect was gradually improved. The effluent water was clear and the SVI returned gradually, but the SVI eventually maintained at 150mL/g without retune to previous range.

Abstract: In this paper, the influences of different binders (Hydroxypropyl Methyl Cellulose (HPMC), Carboxymethyl Cellulose Sodium (CMC), Polytetrafluoroethylene (PTFE) and Styrene- butadiene Rubber (SBR)) on high-rate discharge performances at low temperature for the negative electrode of Ni/MH battery have been studied by orthogonal experimental design. Electrochemical measurements have been conducted to investigate the capacity, charge-discharge performance, cyclic voltammetry and electrochemical impedance characteristics. The surface morphology and chemical compositions have been investigated by SEM and EDS. Based on the range analysis, the primary and secondary influence factors as well as the optimization results were obtained. From the CV characteristic curves, the oxidization peaks and reduction peaks are not clearly shown, which indicates that the redox reaction does not occur clearly after binders added. The EIS experiments show that the deterioration of the voltage characteristic of the battery is due to drying out of the separator that increases the ohmic resistance (Rs ), and the decay of the discharge capacity is due to the passivity surface that increases the charge-transfer resistance (Rt) of the battery.

Abstract: Styrene-butadiene rubber (SBR) nanocomposites were prepared from organically modified montmorillonite (OMMT). To enhace the dispersion properties of OMMT in SBR matrix, polybutadiene was modified with tetramethyl siloxane substituted with benzylamine, and the master batches of those were prepared by a solution process using tetrahydrofuran. SBR/master batch nanocomposites could be obtained by melt-compounding followed by hot-press vulcanization. Xray diffraction (XRD) studies revealed that the interlayer distances of OMMT were increased and the nanocomposites had the intercalated and exfoliated structures of OMMT by the nanocomposition of SBR with the master batch. Mechanical and dispersion properties of the nanocomposites from the master batch are superior to those of nanocomposites without master batch.