| The malodorous urban rivers not only hamper the exploitation and sustainable development of city economy, but also have a serious impact on the coastal residents. It has many advantages of using eco-technology to treat the malodorous river, more stability, higher efficiency, lower energy cost and easier management. This thesis was based on the major National Water Pollution Control Project (2009ZX07317-006) " Research and Demonstration on Sewage Interception, Engineering Remediation and Ecological Restoration of the Malodorous Urban Rivers". By using ecological techniques to treat the seriously-polluted urban rivers of Shanghai as a demonstration project, the research investigated the coupling effect, mechanism and demonstrative effect in water quality purification and habitat improvement malodorous urban rivers. The study could provide scientific basis for technical design and engineering application to improve the water quality of polluted urban river.Static adsorption and desorption experiments were carried out to study a new type of substrate's adsorption of pumice, The results suggested that:(1)the adsorption reaction of ammonia nitrogen by pumice was rapid, but dynamic adsorption equilibrium, difficult to desorption. The adsorption kinetics analysis fitted it well with the pseudo-second order kinetic reaction model; (2)the adsorbing amount of pumice increased with the rise of initial concentration of ammonia nitrogen, but high initial concentration (> 535 mg/L) could inhibit the adsorption by the fitting result of Langmuir formula; (3)because of the chemical absorption of pumice, the influence of temperature expressed the duality, the balanced adsorbing increased with the temperature rising when it was lower than 313 K, but decrease as it was higher than 313 K; (4)the adsorption isotherm conformed to the Langmuir and Fredulich isothermal equation very well. It's a kind of favorable absorption from both RL value and 1/n value.This study focused on the clonal plant cultured by the malodorous river water, detected morphological indexes of four plants(plant height, stem diameter, leaf area, tiller number, spacer length) and dynamic drift of chlorophyll content in the leaves(chla, chlb). Though regression analysis of clonal plant's responses and strategies under high nutrient levels and the drift ratio of N/P, the results showed that: (1)Exogenous nitrogen had obvious effects on phenotypic plasticity of clonal plant, however, exogenous phosphorus had no significant effects on it; (2) different types of exogenous nitrogen had a significant different influence on four kinds of clonal plants phenotypic plasticity: in terms of the morphological characteristics, there was a significant negative correlation between four hydrophytes and ammonia nitrogen concentration, and a significant positive correlation with nitrate nitrogen. For the chlorophyll content, there was a significant negative correlation between Nymphaea tetragona and Myriophyllum verticillatum and nitrate nitrogen, and a significant positive correlation in the case of Pontederia cordata. However, Hydrocotyle vulgaris is not obvious. (3)the distribution of nutrients in complete stool of four hydrophytes was not influenced by exogenous nitrogen,but it had significant variance in different organs: there was a significant positive correlation between Pontederia cordata root's N/P and nitrite concentration, Nymphaea tetragona tuber's N/P and ammonia nitrogen, Myriophyllum verticillatum root's N/P and total nitrogen .however, there was a significant negative correlation between Hydrocotyle vulgaris and total nitrogen.Based on the pre-research, this paper performed the enhanced treatment of malodorous river water using the combined process of Biofilm Grid -Integrated Vertical flow Constructed Wetland with pumice and fiber filler as packing material, the hydraulic loading was designed as 0.80 m3/(m2.d).After 6 months study, the results were summarized as follows:(1)It had a better efficiency on the removal of major pollutants. The removal rate of COD was 57.20-75.00%, average removal rate of TN was 58.14% and TP was 58.13-83.25%; (2)Compared with pumice and fiber filter, the phosphatase and urease activities were higher in fiber filter, and had a better degradation ability of organic nitrogen, while the phosphorus removal rate was better by using pumice. (3)Using gene library technology to analysis the dominant microorganisms on packing material, there are Acinetobacter sp, Flavobacteriaceae bacterium, Pseudomonas putida and Uncultured Alphaproteobacteria.A set of sequential cascade sunken floating bed was designed for the treatment of malodorous river by simulating ecological niche distribution of hydrophyte in natural water, when HRT is 8h and it was studied for about 6 months. The results were summarized as follows:(1)Based on the traditional floating bed, by choosing a set of hydrophyte in different ecological niche and running by cascade sinking mode. Concentration of DO increased gradually along the water flow, while effluent concentrate increased for about 0.38-3.38 mg/L,with its average 1.51 mg/L. The phosphorus removal ratewas promoted by the aerobic environment which could help the oxidation and fixation of Fe2+and S2-,also Fe2+in the malodorous water could help the sedimentation of phosphorus; (2)The removal rate of NH4+-N was 40.60%-95.90%, with the average is 71.9%.The effluent concentrate of NO3--N and NO2--N were higher than the influent. The average removal rate of total inorganic nitrogen was 45%, mainly in the units of emergent macrophyte, where the ANAMMOX mechanism existed on the packing material according to the analysis of gene library technique. Also, the removal of total inorganic nitrogen pathway involved anaerobic ammonium oxidation reaction.(3)The bacterial community differed significantly from its adjacent purified unit, which present dominated bacterial community from facultative anaerobes to aerobic bacteria and facultative anaerobe along the water flow; (4)The system had a significant effect on the species diversity index of phytoplankton by shielding effect of plants and water quality improvement.On the basis of preliminary studies, by using Staged Floating Treatment Wetlands as a Demonstration Project in Xin Jiao Pu river, lies in Shanghai HongQiao Transport Bub area, and set four types of river cross section as a reference object, design 40 three-dimensional Floating Treatment Wetlands were designed and applied, which could make surface coverage to 22%. Compared with the control areas (CK), results from regular monitoring showed that the concentration of dissolved oxygen rised to 2.16-11.08 mg/L in the demonstrate region, transparency increases 22.22%, the removal rate of phosphorus can reach to 92.50%, but planktonic algae density and species Margalef diversity index lower than CK.This study used pumice as new packing material and two optimized new technics: Biofilm Grid & Integrated Vertical-flow Constructed Wetlands (BFG-IVCWs) and Staged Floating Treatment Wetlands (SFTWs) to treat malodorous river, discussed the mechanism of coupling effect of multiple technologies, which could supply a theoretical basis and technical support for its application.
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