Advanced Materials Research Vols. 518-523

Abstract: The process parameters and operation effect of the treatment of comprehensive wastewater of chemical industry park by anaerobic/aerobic bio-contact oxidation process was introduced. This provided a reference of application. Taking a project as an example, process flows, parameters and the size of structures were introduced. Combining with treatment effect, the design features were discussed. The practical operation result showed that the effluent treated by the baffled submerged bio-film process could meet the requirement of classⅡ of the “Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant” (GB18918-2002).

Abstract: An ecological floating beds system was constructed to treat natural urban malodorous river in Changzhou at low temperature. Taking Lolium multiflorum as an example of water plant, the characteristics and contribution of its uptake to total nitrogen (TN), NH4+-N, total phosphorus (TP) and chemical oxygen demand (CODMn) in the system were studied in a period of 80 days. Significant growth of the plant Lolium multiflorum was observed with total biomass ranging from 53 g to 785 g, and the highest growth rates were 8.82 and 9.23 for biomass of above water and under water part, respectively. Different concentrations of TN, NH4+-N, TP and COD were found between in the floating beds and out the floating beds. The highest removal rates of TN, NH4+-N, TP and CODMn using Lolium multiflorum ecological floating beds system were 16.8%, 33.0%,10.8% and 17.8%, respectively. The purification effect of ecological floating beds shows it can be well applied to cleaning natural rivers at low temperatures.

Abstract: The research on the species selection of constructed wetland plants and the purification effects of the plants is crucial in ecological wastewater treatment technology. This paper studies the purification effects of different residence time of sewage water, different constructed wetland plants and their synergistic effect on COD disposal in domestic sewage. The results indicate that the best plant combination in purifying COD is that of Phragmites communis, Typha orientalis and Canna generalis, followed by that of Phragmites communis, Arundo donax and Canna generalis. The best plant species in purifying COD is Typha orientalis, followed by Phragmites communis.

Abstract: At present the point source soil contaminations by toxic chemicals are very serious, and many methods are used for the rapid disposal. In recent years, Fenton’s reagent has been paid more and more attention because of its high oxidative potential and simplicity. In this work, pentachlorophenol (PCP) was used to simulate contaminated soils, and a tilted soil reactor was designed to study its decomposition by Fenton’s reagent. The effects of six variables on PCP degradation were evaluated: (1) initial soil-water ratio; (2) reaction time; (3) H2O2-Fe2+ molar ratio; (4) dosing method; (5) reaction tank rotating speed and (6) initial H2O2 concentration, and the optimum operating conditions were identified. However, further research is required for practical application.

Abstract: To make full use of existing facilities , process reconstruction line is proposed including three precipitation, floatation and biological treatment after the analysis of the problems in existing treatment process of the paper-making wasterwater, The results showed that: after the reconstructive wastewater treatment system, the quality of effluent has reached the secondary standard of Integrated Wastewater Discharge Standard (GB8978-96).

Abstract: The possible use of biowaste-banana skin as an alternative, low-cost biosorbent and reductant for removal of Cr from aqueous solutions was investigated. Effects of pH, contact time, Cr(VI) initial concentration and temperature on the reduction and biosorption of Cr by banana skin were studied. Experimental results showed that 1 g of dried banana skin could reduce about 230 mg of Cr(VI) to Cr(III), at the condition of 30°C, pH 2 and 300 rpm. The maximum Qeq of Cr(III) by banana skin was 6.3mg g^-1 at the Cr(VI) initial concentration of 200mg L^-1, 30°C , pH 2 and 300 rpm.

Abstract: In recent years, researches of functions of REE on Hydrogeology are carried out all over the world. However, little is known about REE characteristics in polluted place that was affected by human beings. In this article, REE characteristics in groundwater which is polluted by Jiaozishan landfill are summarized, furthermore, hydrogeology condition and current pollution situation of research area are combined to analyze the correlativity between ∑REE and other pollution index, which provide a new thinking for groundwater polluted by garbage dump.

Abstract: In this study, the removal of a di-azo dye, C.I. Acid Red 73 synthetic wastewater was investigated using advanced Fenton process based on nanoscale zero-valent iron (NZVI) that was synthesized by the aqueous phase borohydride reduction method in the laboratory. NZVI has been characterized by SEM. The influences of NZVI dosage, H2O2 concentration and initial pH value in the process of dye removal by advanced Fenton process were studied in a batch setting. The color removal efficiency was found to be decreased with increase of initial pH, and increased with increase of NZVI and H2O2 concentration. By using proposed process with NZVI dose of 0.02 g/L and H2O2 concentration of 1.0 mM, at 30 min the Acid Red 73 color removal was more than 90%.

Abstract: Adsorption experiment was conducted to investigate the removal of cadmium (Cd) from aqueous solutions by blast furnace slag. Results showed that the pH, initial Cd concentration, contact time and blast furnace slag dosage had significant effects on Cd removal from aqueous solution. The Cd removal rate was more than 98% with 2 h contact time, 0.200g slag dosage, neutral and alkaline solution and 10 mg L-1 initial Cd concentration. Our results have shown that blast furnace slag is an efficient adsorbent for the removal of Cd from aqueous solution.

Abstract: This paper presents a study of the removal of trace Cd2+ from light-polluted water by using weak base epoxy anion-exchange resin as adsorbent. A series of experiments was conducted to examine the effects of resin dosage, contacting time and coexisting ions. In the present research, it was found that Cd2+ can be effectively removed from light-polluted water with high concentrations of alkaline and alkaline earth metals by weak base epoxy anion-exchange resin. The adsorption isotherm can be well described by Langmuir isotherm. The adsorption processes followed the first-order rate kinetics.