Advanced Materials Research Vols. 838-841

Abstract: The research on ultrafiltration membrane assisted by powdered zeolite for the treatment of secondary effluent from a municipal wastewater treatment plant was studied. The results show that membrane fouling rate is reduced by pre-coating the ultrafiltration membrane with powdered zeolite, and the treatment performance of secondary effluent is enhanced. UV-vis, three-dimensional excitation emission matrix (3D-EEM) fluorescence spectra and scanning electron microscopy (SEM) images for ultrafiltration were also discussed.

Abstract: Photo-degradation alkali lignin was prepared in sunlight by the system of TiO₂ and squaraine dye (QSC). The influence of the ratio of QSC to TiO₂ on the solar energy conversion efficiency was tested; the principle of degradation alkali lignin by TiO₂ photocatalyst in sunlight was researched. The results showed that the number-average and mass-average molecular mass of degradation alkali lignin and the control lignin were 1,548 and 2,822, respectively, the phenolic hydroxyl of degradation alkali lignin is 5.63% with the control is 4.64%, and alcoholic hydroxyl of degradation alkali lignin is 3.21% with the control is 3.77%.

Abstract: The objective of this work was to study the effect of some operating condition on the simultaneous removal of NO and SO₂ from simulated flue gas in the lab-scale agitated bubbling reactor. The experimental results showed that NO removal efficiency increased with the increase in the molar ratio of O₃/NO, while removal efficiency of SO₂ decreased. When absorption liquid changed from distilled water to Na₂CO₃ solution, it is observed that removal efficiencies of NO and SO₂ increase with the increase in the concentration of Na₂CO₃ solution. At 0.08 mol/L of Na₂CO₃ solution, the removal efficiencies of SO₂ and NO are 100% and 93%, respectively

Abstract: The research progress on the oxic-settling-anaerobic sludge reduction process at home and abroad was reviewed, which was focused on the progress of sludge reduction mechanism, operating performance, impact factors and microbiological characteristics of OSA process. Then the shortcomings of the OSA process were analyzed and its development was also predicted.

Abstract: In allusion to Cr³⁺s toxic effect on activated sludge in SBR process system, by determination of the Cr³⁺ adsorption rate, mlvss under different initial SVIs and different chromium loads, the Cr³⁺s toxic effect on activated sludge and the Cr³⁺s influence on chromium adsorption of activated sludge were studied. The research shows that within tolerance range, the activated sludge of SBR system can adsorb 60% chromium ion within 10min reaction. Moreover, with the increase of chromium load, the final chromium remnant rate decreases; within tolerance range, the increase of chromium load contributes to the adsorption of chromium ion and the acceleration is subject to initial SVI. Within non-tolerance range, the ability of SBR process system to adsorb chromium decreases greatly; The whole curve of chromium remnant rate shifts upward with the increase of chromium load level. Within 10mins reaction, the adsorption rate of chromium is about 50% under best condition.

Abstract: A novel process for improving the energy use and treatment efficiency of the biological nitrogen removal process, up-flow microaerobic-oxic (M/O) process which is composed of up-flow micro-aerobic and aeration was proposed based on a laboratory scale for domestic wastewater treatment, the dissolved oxygen (DO) in up-flow micro-aerobic was in the range of (0~0.5) mg/L. The M/O process performance under different hydraulic retention time (HRT) and Internal return ratio (r) was investigated. Under the optimal conditions, the average removal efficiencies of chemical oxygen demand (COD), total nitrogen (TN) and ammonium nitrogen (NH₄⁺-N) were 89.1%, 64.1%, and 96.6 % with effluent concentrations of COD, TN and NH₄⁺-N less than 50,15 and 8mg/L, respectively. The distribution of sludge particles diameter and microbial activity of activated sludge were also measured, the mean particle diameter was in the range of 180~250μm and the SOUR_T was 13.11 mgO₂/(gMLVSSh). Up-flow micro-aerobic (M/O) reactor has the advantages of more stable performance and better resistance to the load shock than the conventional A/O process within continuous running period of 130 days.

Abstract: A strain isolated from activative sludge, on microbial degradation of malachite green and its enzymatic mechanism was studied. The isolation of microorganism, malachite green degradation and enzyme activity assay experiment, was determined the effects of microbial degradation of malachite green and its mechanism. The 16SrDNA gene sequence of a malachite degrading bacterial isolated was 99.8% similar to Pseudomonas aeruginosa AS2 and identified as Pseudomonas aeruginosa. The P. aeruginosa strain could degrade malachite green in the 4000 mg.L^-1, and its degrading volcity was positively related to PPO and CMCase activities. The isolation has ability on degrading of high concentration of malachite green.

Abstract: Coking wastewater RO brine is considered to be refractory, toxic, mutagenic and carcinogenic. Electrochemical oxidation has attracted wide attention in wastewater treatment because of its strong oxidation performance and ease of control. In this paper, the electrochemical degradation of NH₃-N and COD were investigated at different anodes materials and current densities .The electrochemical oxidation using Ti/RuO₂IrO₂ anode was effective and promising for advanced treatment of coking wastewater RO brine. COD and NH₃-N concentration degraded 86% and 100% in 80min at the current density of 5 mA cm^-2. Current density is the most important factor of organic degradation and energy consumption. When the current density was 10mA cm^-2, the COD removal ratio quickly increased to 52.94% in 20min reaction time, but under high current density, the life of the electrode will be reduced. When the current density is too low, the electrolytic reaction time to reach standard needs to be 2h or more, which will perpetuate the equipment bulky, increase the cost of the equipment. The optimal current density is 5.0 ~ 7.5 mA cm^-2. Unit per COD energy consumption is 114.4 kWh kgCOD^-1, and unit per cubic meter wastewater energy consumption is 5.9 kWh m^-3 at the current density of 5 mA cm^-2.

Abstract: Jin 45 heavy oil block in Liao he oil field has entered the late steam huff and puff period,Flooded serious,Average single well daily oil producing is 0.74t/d, Water recovery rate reaches as high as 260%, It is extremely urgent to convert to Steam flooding development mode ,but without corresponding theoretical basis in heavy water flooded area. Take two test well groups with scale out two well spacing as object of study, Use Petrel software for accurate geologic modeling, Bring into steam huff and puff history matching through CMG software, and then make a steam flooding feasibility prediction in heavy water flooded area. During the prediction, the huge edge water and bottom water body was set up around the model. The result of numerical simulation manifested that Water invasion rule give priority to bottom water coning, Edge water invasion is not large, Outside casing wall channeling formed water flooded in severe cases; Reservoir has been formed basically thermal union;Reservoir remaining oil saturation is 44.96%,Formation pressure is 2.91 MPaContinuous steam injection make the formation pressure increases, inhibit water cut increasing rate and water cut increasing rate, The serious water invasion problem could be effectively relieved; In the five years forecast after steam flooding, the cumulative recovery degree is 7.74%, the development effect is improved. It proved that Liao he oil field Jin 45 heavy oil heavy water flooded area turn steam flooding development is feasible. The study provides a theoretical basis for heavy flooded area of heavy oil reservoirs to turn to steam flooding development.

Abstract: The flow distribution in flue pipes has a great effect on collection efficiency.Gas pressure and velocity distribution in flue pipes upstream electrostatic precipitator were investigated using computational fluid dynamics (CFD) in this paper. The flue pipe model was established on the basis of standard straight and bended flue pipe which were widely used in engineering. And the availability of numerical simulation model was verified by comparing the empirical curve and the numerical simulation results of a common pipe bend without inner supports. In the same condition, these two flue pipes were simulated. The result shows that inner supports have great impact on flue pipe and the values of the pressure drops are closely linked to airflow directions. These results can provide theoretical basis and method guidance for design of inner support.