Papers by Keyword: High Concentration

Abstract: The marine oil and gas transmission pipelines should be washed by phosphoric acid solution before they were used. The washing wastewater, containing high level of phosphorus, was treated by calcium chloride. The response surface method (RSM) based on Box-Behnken was adopted to consider the impact of n (Ca):n (P), pH and reaction temperature on total phosphorus (TP) removal rate. In this work, the Design-Expert 8.0.6 was employed to design and analyze the results. Then, a quadratic polynomial model was built with TP removal rate as the response value. It was shown that the n (Ca):n (P) and pH have a significant effect on TP removal rate. The interaction of pH and temperature is significant. The optimum conditions were X₁=3.40, X₂=10.97, X₃=38.12. In this condition, the predicted value of TP removal rate is 99.9242% while the average removal rate of verification is 99.9365%, which was shown that the predicted value was identical with experiment value.

Abstract: In past years, the exploitation of mineral resource in our country was stressed on capacity and the solid waste recycle and innocent treatment was ignored. Much valuable metal is associated and coexist with waste, it is in difficult position for present technology to recycle valuable composition in that waste, which leads to valuable component loss and environment pollution. Therefore, the development and utilization of copper refining slag is in significance. In this paper, the advantages and difficulties to process refining slag by flotation method are discussed based on property analysis of copper refining slag. The refining slag is featured by high specific gravity, high concentration, and its particles distributing at both ends of small and large size. A flotation cell with special structure of barrier grid plate and multi-loop channel is developed for refining slag processing, which provides a proper way to solve the sediment problem during refining slag flotation. The application of CLF-40(effective volume,40m3) flotation cell for processing slag mixture from flash furnace and converter is expounded, the production index shows that the Cu grade is up to 27.18% at recovery of 83.93% when slurry concentrate being 70%

Abstract: High-concentration anaerobic fermentation of dairy manure was investigated using an anaerobic batch reactor under laboratory conditions at 20°C. Daily average productive rate of COD_VFA was used as response functions, and three factors (temperature, liquid concentration, and retention time) were selected as input variables in the process of hydrolysis and acidogenesis of dairy manure. The study used a central composite rotatable orthogonal experimental design. The influential regularities of every parameter on every index were analyzed with a single-parameter method. The ranges of temperature, liquid concentration and retention time were 25°C to 35°C, 6% to 10%,and 2 to 12 days respectively. Experimental results showed that daily average productive rate of COD_VFA was greatly influenced by temperature, with retention time a secondary influence, and liquid concentration having the least influence.

Abstract: Dynamic and thermodynamic characteristics of gasoline vapor adsorption at 0.3 mol/mol on different activated carbons (ACs) were investigated. The adsorption capacities of AC1 and AC3 were 0.295 g/g and 0.189 g/g at 20 oC, and 0.284 g/g and 0.165 g/g at 30 °C, respectively. Bed temperature rise was up to 50°C to 60°C in the adsorption of gasoline vapor at 0.3 mol/mol.The heat effect formula for high concentration vapor adsorption was deduced to evaluate the relationship of the adsorption capacity of the activated carbons, the mole fraction of the inlet gasoline vapor, the recovery efficiency of the gasoline vapor with the temperature rise.

Abstract: Conductive ink, especially the nano-silver ink is becoming more and more popular in printable electronic field. In order to synthesize high concentration, stable nano-silver colloid, liquid chemical reduction is used and different ratios of PVP to silver nitrate are studied. After precise adjustments of the parameters, colloid with silver content of wt7.8% is obtained. Particle size distribution, UV-Vis spectra, thermo gravimetric analysis and SEM images are conducted to characterize the silver particles. The results show that when molar ratio of PVP to silver nitrate is 0.6, the average particle size is 170nm and some deposit can be seen, while the ratio increases to 1.5, the size decreases to 68nm, and the residue quality of the silver colloid showed in the TG analysis is 7.88%. After aging for 1 month, the colloid is still stable and the color keeps to the original dark green. When the ratio continues increasing to 2.5, particle size becomes 112nm and some larger particles beyond 3μm can be observed.

Abstract: One new kind of gas distribution plate used for high concentration electrostatic precipitator (herein after briefing ESP) designed in this content in order to solve the problem that gas discharges can not reach the required standard existed in high concentration ESP. Research the influence that the structure type of gas distribution plate to gas flow distribution plate by compare and analysis the experimental object analogue and computer data analogue. Advantage the gas distribution plate design according to experiment and outstandingly improve the gas-purging performance of high concentration ESP and ensure the electric field section flows velocity evenly in industry application ESP.

Abstract: Cuprous oxide nanoparticles at high concentration (up to 0.3M) were successfully synthesized by modified polyol process. The redispersion stability could be controlled by optimizing various conditions like polymer concentration, temperature, reductant, and catalyst. Reductant and catalyst play a crucial rule in redispersion of cuprous nanoparticles. Under poor conditions, particles grow to larger sizes due to aggregation of nanoparticles. This modified polyol process allows monodispersed cuprous oxide to be obtained on gram scale in a single reaction and make possible a high synthetic yield of more than 80%.

Abstract: This paper reports a new laser conditioning method for micro-wheels with ultra-fine grit diamond, which are used for the micro grinding of micro-aspherical optics. Resinoid-bonded micro-wheels with ultra-fine grit diamonds are used for micro grinding. Such small wheels have the problem of poor ground surface roughness due to their few effective cutting edges and low peripheral speeds. In the present work, new truing and dressing methods are proposed to produce many effective cutting edges. The new method uses the third harmonic of a Nd:YAG laser, which is suitable for processing resinoid bond material. It was found that a SD1500B wheel treated using the new method had a higher cutting edge density than one treated using a conventional method, the cup truer method. A good surface roughness was obtained using the new method.