三磷酸腺苷及生物威胁指数与活性污泥法常规指标的相关性分析:以某精细化工废水处理设施为例

CORRELATION ANALYSIS AMONG ATP, BIOLOGICAL STRESS INDEX AND COMMON INDICES IN ACTIVATED SLUDGE PROCESS, ILLUSTRATED BY A CASE OF TREATMENT FACILITIES IN A FINE CHEMICAL FACTORY

以江苏某精细化工厂好氧工艺为研究对象,在进行常规活性污泥工艺运营监测的基础上,通过监测活性污泥三磷酸腺苷(adenosine triphosphate, ATP)浓度来表征微生物状态,并利用ATP数据计算工艺的生物威胁指数(biological stress index, BSI)。运用Spearman相关系数法探究ATP、BSI与常规活性污泥指标的相关性,并运用LOESS(locally estimated scatterplot smoothing)法探究ATP与常规参数协同评估预测生化处理工艺运行状况的可能性。结果表明:cATP与MLSS在0.01显著性水平上具有相关性,且cATP与MLSS相关系数达到0.622。BSI的变化趋势与COD负荷、C∶N、SV_(30)和SVI均具有较好的相关性,其中BSI与SV_(30)和SVI的Spearman相关性系数相对更高,分别达到0.613和0.691。LOESS分析表明:BSI的变化趋势较SVI和SV_(30)提前14 d,可作为污泥膨胀的预警指标;同时,为避免工艺恶化,建议日常运营中BSI维持在20%以下。

In this paper, the concentration of Adenosine Triphosphate(ATP) in the aerobic tank from a biological wastewater treatment process, in addition to conventional operation indicators, was monitored at a fine chemical factory in Jiangsu Province, China. And then, biological stress index(BSI) was calculated based on the ATP data. Correlations among ATP, BSI and other conventional activated sludge indicators were investigated by using Spearman correlation coefficient method. Furthermore, the feasibility of using ATP and BSI to evaluate and predict the operation status of biochemical treatment process was explored by using locally estimated scatterplot smoothing(LOESS) method. The results showed that cATP was correlated with MLSS at a significance level of 0.01, and the Spearman correlation coefficient between them was 0.622. BSI can be used as an early warning indicator for sludge bulking, and the fluctuation of BSI was significantly correlated to COD loading, carbon-nitrogen ratio, SV_(30), and SVI. The LOESS curve showed that BSI can be used as an early prediction for the trend of SVI and SV_(30) with a 14-days lead. The analysis suggested that maintaining a relative low level of BSI(<20%) can be used in practice as a control line to evaluate the status of the activated sludge process.