Advanced Materials Research Vols. 518-523

Abstract: The concentration of soluble inert organics and the mass distribution of organic matter in inflow wastewater of one wastewater treatment plant (WWTP) in Qingdao city in China were studied in this paper. The results showed that the concentration of soluble inert organics in the influent which cannot be degraded by microbe was about 20 mg/L, accounts for 2%～5% of all dissolved organic matter. The small organic molecules (<1 ku) took up the largest proportion of all organics in influent, which was about 40% of dissolved organic carbon (DOC). Moreover, the residual organic molecules after biological treatment process and coagulation sedimentation process might be transformed into disinfection by-products (DBPs) by chlorination in advanced treatment process, so the combined process of ozone and activated carbon was suggested to be used to remove the small organic molecules in inflow water in this WWTP.

Abstract: Microbubble generators are the most important part for microbubble flotation technology, especially for water treatment. The paper introduced many types and functions of microbubble generators and their development Tendency. It found an efficient method for analyzing mechanical microbubble generators and summarized applications of microbubble generators. It will be useful for analyzing and applying microbubble generators.

Abstract: Sediment dredging is currently the most commonly selected option for getting rid of contaminated sediments. In this study, the effects of estuary dredging on removing nitrogen and phosphorus were investigated by comparing the different vertical nutrient content between the dredged and un-dredged areas in Dianchi Lake. The results showed that the contents of total nitrogen and total phosphorus in the un-dredged areas were relatively higher than that in dredged areas. Besides, the contents of bio-available nitrogen and phosphorus represented the similar results, only a few dredged spots showed a higher potential releasing capacity. Therefore, with the reduction of internal nutrient loading, it indicated that sediment dredging might be an effective and reliable way to improve such eutrophic lakes.

Abstract: A soil column leaching experiment was conducted to investigate the influence of citric, oxalic and acetic acid on release characteristics of phosphorus. The results showed that for 5 mmol/L organic acid concentration, the ability of three organic acid to activate phosphorus in the soil was at the order of: citric>acetic>oxalic acid. Different treatments result in various phosphorus release characteristics. For citric acid treatment, phosphorus concentrations of effluents increased with effluent volume at the begining, there was a comparatively steady state at high level during 1000-3050 ml leachate volume after reached the highest value, then P concentration declined and became lower than the detection limit finally. For the oxalic acid, a regular decrease of P concentration was observed during the column leaching, and it droped to extremely low concentration rapidly. During the column leaching with acetic acid, the amount of P in the effluents initially increased, and then declined gradually. Though P_max and P_max/T are not significantly higher than the values of oxalic acid treatment and CK, acetic acid treatment showed a relatively strong sustainability during column study. The variations of pH during column leaching with citric, oxalic and acetic acid followed the trend: citric>acetic>oxalic acid, which is the same as the order of the mobilizing ability of organic acids for phosphorus.

Abstract: This paper studies on the field application of microbial technology used in bioremediation of urban polluted river. Xuxi River, a heavily polluted urban river, had been maken the treatment as the research object. In this treatment, Xuxi River was directly added indigenous microorganism agent and microbiological accelerating agent into the river water and sediment in the special inoculation way, without artificial aeration and sediment dredging. After this treatment， the removal rates of COD, TP and NH₃-N are up to 43%、56% and 58%, DO increases to 2mg/L, the Nemerow index reduces to 2.2 from 6.4, and a lot of water earthworms and a school of fish reappear. The results indicate that this microbial technology can effectively alleviate the pollution, promote the water quality, and restore the river ecosystem.

Abstract: Baiyangdian lake is typical macrophytic lake, located in North China. With the economic and social development, as well as the impact of global climate change, the water pollution problem has been being a serious impact on the salubrious development of regional ecosystems. The local government has adopted a change of water storage basin to approach to fundamentally solve the problems of water pollution with the ecological water transfer in lake basins. In this paper, collecting the typical water pollutants data before and after ecological water transfer, using of ArcGIS software we have researched the diffusion mode and the enrichment regulation of the water pollutants from the perspective of spatial distribution caused by the ecological water transfer. The results show that there has a strong detention of the pollutants spread in Baiyangdian lake. With the ecological water transfer, there is a positive significance onto the local water deterioration, but not a fundamental solution onto the whole lake environmental issues. It still needs to develop the integrated control-rehabilitation managements and technologies for water pollutants combined with special land-water broken terrain and the local climate in Baiyangdian lake.

Abstract: This paper analyze the operation condition of some waste-water stations based on DEA , find the optimization operation model of waste-water treatment stations in oilfield with C2R model with negative pollutants. The calculating examples has proved that the efficiency of waste-water treatment is obviously improved in this method.

Abstract: TiO₂/active carbon (AC) photo catalysts are prepared by sol-gel method. We have designed a fluidized bed reactor to decontaminate the formaldehyde. In our experiment, active carbon and TiO₂/AC are used as the air purification materials in the reactor. Flat aluminum sheets and electric field are introduced into the reactor. Our result shows that TiO₂/AC materials have high removal rate, and it can reach 80%. When we add flat sheets and stable electric field, the removal rate reach over 90%.

Abstract: The paper is aimed at studying the purification effects of COD, TN, TP and SS to waste kitchen water by using three different wetlands constituted by a single oenanthe javanica, single acorus calanmus, oenanthe javanica+acorus calanmus mixed configuration under the same load and the same hydraulic conditions. The results showed that oenanthe javanica is effectual for removing COD and TN, acorus calanmus is effectual for removing TP. As for the way of configuration, single configuration is preferred for removing COD, mixed configuration is preferred for removing TN and TP, the effect of the three configurations for removing SS is generally of the same level.

Abstract: Graphene oxide–polyamine composites have been synthesized which have metal ion capacities as high as 97.94% for cadmium ions removed from aqueous solutions. The chemical structure of obtained graphene oxide–polyamine composites was confirmed by FT-IR, XRD and SEM. The results revealed that these composites can effectively extract heavy metal ions from waste water. Using these composites the concentration of heavy metal ions is reduced to below allowable discharge limits and the recovery of heavy metal ions from waste water was realized.