| With the development of economy and the improvement of people’s living standard, therequirement of water area in people’s life is increasing. Artificial landscapes have so manyfunctions, such as beautifying the environment, flood protection and adjusting the ecologicalenvironment, that they are widely used in people’s lives. At the same time, problems causedby water quality deterioration cannot be ignored. Therefore, it is essential to carry out thewater quality identification and the research of controlling pollutions discharging. It will makesense to ensure its functions and improve the aquatic ecological environment.In this paper, an artificial river system in Qingdao National High-tech IndustrialDevelopment Zone was investigated. Facing the polluted status and the main environmentalissues, water quality identification and eutrophic evaluation were taken after a long-timemonitoring of water quality and field investigation. The influence caused by the water qualityindexes to the eutrophication of the artificial river system was also analyzed. Besides, thewastewater advanced treatment process was optimized in order to utilize the reclaimed waterfor landscape. The research mainly includes as follows:(A) The water quality analyzing andidentification of the artificial river system. They were done by a long-time monitoring of mainpollutants concentration and the situation of water quality.(B) The eutrophic evaluation andanalyzing of influencing factors. Utilizing the monitoring data, the eutrophic level of theartificial river system were determined by the eutrophic evaluation. And the influence to theriver system caused by certain water quality indexes was analyzed.(C) The wastewateradvanced treatment process optimization of WWTP whose effluent would discharging intolandscape. To avoid the damage causing by reusing the effluent of the WWTP, the feasibilityof coagulation/sedimetation technique was investigated and the reasonable coagulant dosageand pH value in the wastewater advanced treatment process were determined.(A) The water quality analyzing and identification results are as follows:The water temperature benefited the growing of algae at most of the year. The salinitychanged between different sampling points during the whole year. The high concentration ofsuspended solids、turbidity and colority brought people uncomfortable feelings. The waterwas slightly alkaline. The oxygen concentration was supersaturated because of the growing of algae. The artificial river system had a high concentration of organic pollutants and poorbiochemical quality. The main pollution factor was total nitrogen. Destroying its ornamentalvalue, eutrophication has occured in the artificial river system.Water was polluted in the artificial river system in which main polluted factors were TN、CODCrand potential polluted factor was CODMn. The percentage of water quality which couldsatisfy the fifth kind of <Environmental standards of surface water> in the eight samplingpoints were3.0%、97.1%、48.5%、53%、63.6%、26.5%、67.7%and69.7%.(B) The eutrophic evaluation and influencing factors’ analyzing results are as follows:Eutrophication which occurred at most of the sampling points except for only onesampling point in the artificial river system was serious. Their eutrophic level were mezzoeven severe.The concentration rate of nitrogen and phosphorus was conductive to the algae growing.Phosphorus was the primary limiting factor of eutrophication. The adapted hydrauliccondition、water temperature、dissolved oxygen and pH value could bring about the releasingof phosphorus from sludge to water, which would lead to eutrophication of the artificial riversystem.(C) The results of WWTP’s advanced treatment process optimization are as follows:Considering the concentration of phosphorus and SS in the artificial river system andeffluent of the WWTP, the optimizing dosage were10mg/L、20mg/L、25mg/L adjusting to thedifferent concentration of phosphorus in the raw water while the optimizing pH value were7.0、6.0、6.0. The effluent after advanced treated under the optimizing condition would notdeteriorate the water quality as it could dilute the concentration of alkalinity、turbidity andcolority. Discharging of the effluent from WWTP could promote the improving of waterquality in the artificial river system. |
PDF Full Text Request