活性污泥系統處理製革廢水之性能評析及模式模擬

Performance evaluation and model simulation of full-scale activated sludge system treating tannery wastewater

蔣春茂(Chun-Mao Chiang)

指導教授 ： 黃汝賢

共同指導教授 ： 周信賢(Hsin-Hsien Chou)

崑山科技大學/工程學院/環境工程研究所/碩士(2011年)

https://doi.org/10.6828/KSU.2011.00087

摘要

本研究對象為南部某製革廠處理實際廢水之活性污泥系統實廠，為了評估該活性污泥系統之處理性能，除了收集過去ㄧ年該廠之操作數據(進流量、處理前後水質及曝氣池污泥濃度)外，吾人亦進行七次之採樣分析、生物相觀察及測定污泥容積指數(SVI)、污泥比攝氧率(SOUR)。本研究亦依據質量平衡關係建立活性污泥系統處理製革廢水之基質降解動力模式，模式中涵蓋之基質降解動力式包括：modified Monod kinetics、Grau kinetics及modified Grau kinetics。上述各種基質降解動力式所需之生物動力參數，則由該活性污泥系統取出污泥混合液，再以批次反應器進行皮革廢水基質降解試驗求得，最後以該活性污泥系統之操作數據驗證動力模式之適用性。
該製革廠之平均廢水進流量為1200 m3/d，進流COD及SS分別濃度分別為6000~8000 mg/L及2000~3000 mg/L，經化學混凝程序處理後，COD濃度降至2500~3600 mg/L，SS濃度則降至90~200 mg/L。後續之活性污泥系統在COD進流濃度2500~3600 mg/L、曝氣池污泥濃度2970~5110 mg MLVSS/L (MLVSS/MLSS ≒ 0.45)、有機負荷率1.0~1.4 kg COD/m3-d (食微比F/M = 0.22~0.5 kg COD/kg MLVSS-d)之操作條件下，COD去除率為87~92% (出流水COD濃度為188~440 mg/L)。該活性污泥系統之污泥混合液以批次反應器(加入製革廢水基質)求得之modified Monod生物動力參數k及Ks分別為2.4~3.6 mg COD/mg VSS-d及290~381 mg COD/L；Grau生物動力參數kG為0.4~2.1 mg COD/mg VSS-d；modified Grau生物動力參數則為1.0~4.3 mg COD/mg VSS-d。最後以活性污泥系統實廠之實驗數據驗證三種動力模式之適用性，結果以modified Monod動力式模擬所得之COD去除率與實驗值之誤差為最小(-0.3%)，其次為modified Grau動力式者(-6.4%)，Grau 動力式者之誤差則最大(-8.1%)。

關鍵字

活性污泥 ； 製革廢水 ； 基質降解動力 ； 動力模式 ； 模式驗證

並列摘要

A full-scale activated sludge system treating tannery wastewater in southern Taiwan was chosen in the present study. In order to evaluate the performance of the activated sludge system, not only the operating data (inflow rate, inflow and outflow water quality, and biomass concentration in aeration tanks) in the past year were collected but seven-time sampling and analyzing works, microbial (protozoa) examination, sludge volume index (SVI) and specific oxygen utilization rates (SOUR) were also carried out or determined by us. In addition, three kinetic models that can be used for simulating variations in substrate (COD) residual concentrations in the activated sludge system were also respectively formulated in a way that included modified Monod kinetics, Grau kinetics, and modified Grau kinetics. All the essential kinetic parameters (k, Ks, kG, kG,M) for model simulation were determined by using a batch reactor method together with suspended biomass removed from the activated sludge system. Finally, the three kinetic models were validated by experiments (i.e., the performance data of the activated sludge system).

The average inflow rate of the activated sludge system treating tannery wastewater was 1200 m3/d with COD concentrations of 6000–8000 mg/L and SS concentrations of 2000–3000 mg/L. After chemical coagulation treatment, the COD and SS concentrations declined to 2500–3600 and 90–200 mg/L, respectively. When the activated sludge system was operated at influent COD concentrations of 2500–3600 mg/L, biomass concentrations of 2970–5110 mg MLVSS/L (MLVSS/MLSS = 0.45), and organic loading rates of 1.0–1.4 (F/M = 0.22–0.5 kg COD/kg MLVSS-d), the COD removal efficiencies were 87%–92% (i.e., outflow COD concentrations = 188–440 mg/L). By using the batch reactor method, the obtained modified Monod kinetic parameters k and Ks were 2.4–3.6 mg COD/mg VSS-d and 290–381 mg COD/L, respectively, the Grau kinetic parameter kG was 0.4–2.1 mg COD/mg VSS-d, and the modified Grau kinetic parameter kG,M was 1.0–4.3 mg COD/mg VSS-d. Finally, the simulated results of COD residual concentrations indicate that the modified Monod model achieves the least deviation from the performance data (-0.3%), the modified Grau model achieves the next deviation (-6.4%), the Grau model achieves the greatest deviation (-8.1%).

並列關鍵字

activated sludge ； tannery wastewater ； substrate degradation kinetics ； kinetic model ； model validation by experiments

參考文獻

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