【摘要】：入海排污是沿海地區(qū)污水處理廠尾水處置的主要途徑,但不合理的排污口布設也會對海洋環(huán)境和敏感功能區(qū)造成不利影響。因此,如何科學合理地選取排污口位置是污水處理廠工程設計中的一項重要內容。大連長興島經濟區(qū)計劃新建的西部污水處理廠設計處理能力為8萬t/d,處理后的污水將執(zhí)行《城鎮(zhèn)污水處理廠污染物排放標準》一級A標準,初步設計方案在近岸四類海洋功能區(qū)中擬選了離岸距離不同的三處排污口位置。本文選用近年來廣泛應用于水動力和水質模擬的"環(huán)境流體動力學模型(EFDC)"商業(yè)化軟件,分別預測各排污口尾水排放對受納海域和功能區(qū)的水質影響,并綜合相關指標構建排污口選址適宜性評價體系,以達到對排污口位置方案優(yōu)選的目的。首先應用EFDC模型對長興島附近海域的水動力條件進行數(shù)值模擬,計算結果與監(jiān)測站點的潮流和潮位實測數(shù)據(jù)吻合較好。然后針對三處入海排污口的設計位置,應用EFDC模型模擬計算了兩個全潮周期的代表性污染物的最大濃度包絡范圍。得到在正常工況時,三處排污口的各污染物超四類水質標準值包絡面積分別為 COD:0.04、0、0.03km~2,無機氮(DIN):1.57、0.76、0.47km~2,活性磷酸鹽(AP):0.15、0.09、0.08km~2;在事故狀態(tài)下污水直接排放時各污染物濃度超標的包絡面積分別為 COD:2.49、3.78、2.30km~2,DIN:9.73、7.32、9.50km~2,AP:12.2、5.91、7.09km~2,且漲潮時會造成部分一類功能區(qū)內不同污染物濃度的超標,因此應避免在漲潮期直排。為綜合比較不同排污口位置的環(huán)境影響和經濟成本,基于海域受污染程度和工程建設費用相關指標,構建了排污口選址適宜性的綜合評價體系。權重確定采用了比層次分析法更為簡便實用的有序二元對比法,在對各指標進行重要性定性排序的基礎上,通過依次兩兩對比,根據(jù)模糊比較結果獲得權重。對三處候選排放口的綜合分析結果表明,選擇離岸距離適中且距一類功能區(qū)較遠的一處作為排污口,在環(huán)境影響和成本費用方面具有相對最佳的綜合適宜性。本文提出的研究方法和體系對于入海排污口的選址優(yōu)化問題具有較好的推廣應用價值。
[Abstract]:Sewerage into the sea is the main way to dispose the tail water of sewage treatment plants in coastal areas, but the unreasonable layout of sewage outlets will also have adverse effects on the marine environment and sensitive functional areas. Therefore, how to select the location of sewage outlet scientifically and reasonably is an important content in the design of sewage treatment plant. The designed treatment capacity of the western sewage treatment plant planned for construction in Dalian Changxing Island Economic Zone is 80,000 t / d. The treated sewage will comply with the "Municipal sewage treatment Plant Pollutant discharge Standard" Class A Standard. In the four coastal marine function zones, the preliminary design scheme selected three locations of sewage outlets with different distance from shore. In this paper, the commercial software "Environmental fluid Dynamics Model (EFDC)", which has been widely used in hydrodynamic and water quality simulation in recent years, is used to predict the effect of tail water discharge from each sewage outlet on the water quality of the receiving sea area and the functional area. The evaluation system of location suitability of sewage outlet is constructed by synthesizing relevant indexes to achieve the purpose of optimal selection of the location scheme of sewage outlet. Firstly, the EFDC model is used to simulate the hydrodynamic conditions in the sea area near Changxing Island. The calculated results are in good agreement with the measured data of tidal current and tidal level at the monitoring station. Then the EFDC model is used to simulate and calculate the maximum concentration envelope range of the representative pollutants in two full tidal periods according to the design location of the three sewerage outlets. At normal working conditions, The envelope area of the standard values of the four kinds of pollutants in the three sewerage outlets is COD:0.04,0,0.03km~2, inorganic nitrogen (DIN): 1. 57 7 0. 76% 0.47 km2, and the active phosphate (AP): 0. 15 0. 09 0. 08 km2. The envelope area of each pollutant concentration exceeding the standard when the sewage is discharged directly under the accident condition is COD:2.49,3.78,2.30km~2,DIN:9.73,7.32,9.50km~2,AP:12.2,5.91,7.09km~2, and rises respectively. The tide will cause the concentration of different pollutants in some functional areas to exceed the standard. Therefore, direct discharge should be avoided during the high tide period. In order to comprehensively compare the environmental impact and economic cost of different location of sewage outlet, a comprehensive evaluation system of site selection suitability of sewage outlet was established based on the indexes of pollution degree and construction cost. The weight is determined by using the ordered binary contrast method which is more convenient and practical than the analytic hierarchy process. On the basis of the qualitative ranking of the importance of each index, the weight is obtained according to the fuzzy comparison result by two and two comparisons in turn. The results of comprehensive analysis of three candidate discharge outlets show that the relatively optimal comprehensive suitability in terms of environmental impact and cost can be obtained by selecting a place with a moderate offshore distance and far from a class of functional areas as a sewage discharge outlet. The research method and system proposed in this paper have a good value in popularizing and applying to the location optimization of sewerage outlet.
【學位授予單位】：大連海事大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：X703

【參考文獻】

相關期刊論文 前10條

1 樊喬銘;丁志斌;;基于EFDC的港口污水處理廠排放標準及排污口選劃研究[J];環(huán)境工程;2016年12期

2 賈卓;湯友華;李秀;郭振華;;基于WebGIS的入海排污口信息管理系統(tǒng)的設計與實現(xiàn)[J];海洋技術學報;2016年02期

3 謝森揚;王翠;王金坑;鄭斌鑫;郭洲華;;基于EFDC的九龍江口-廈門灣三維潮流及鹽度數(shù)值模擬研究[J];水動力學研究與進展A輯;2016年01期

4 陳法興;;基于EFDC模型的明湖水庫水質數(shù)值模擬及預測[J];人民黃河;2016年01期

5 徐婉珍;;基于EFDC的潘家口水庫富營養(yǎng)化模擬[J];安徽農業(yè)科學;2015年34期

6 黃軼康;李一平;邱利;薛Pr琦;章雙雙;;基于EFDC模型的長江下游碼頭溢油風險預測[J];水資源保護;2015年01期

7 李孟國;李文丹;韓志遠;肖輝;麥苗;;大連長興島深水港開發(fā)研究[J];水道港口;2014年04期

8 田濤;趙坤;布e，

本文編號：2211464