污泥厌氧发酵过程中基于近红外光谱的COD定量分析

采用厌氧序批式反应器(ASBR)对污水厂剩余污泥进行的中温发酵处理,利用小波去噪对其上清液近红外光谱进行预处理,基于间隔偏最小二乘法(i PLS)建立COD值的校正模型。结果表明两者建立的校正模型线性相关性r=0.9786,校正均方根误差RMSECV=39.13。利用小波去噪与间隔最小偏二乘法进行建模不但可以减少变量数和运算过程,同时模型预测精度也较高,该研究为污泥发酵过程中COD的变化规律提供了一种快速检测的可行分析方法。

Quantitative Analysis of COD in the Anaerobic Sludge Digestion Process through the use of Near Infrared Spectroscopy

The excess active sludge from wastewater treatment plants was fermented with anaerobic sequence batch reactor(ASBR). The near infrared (NIR) spectra of the supernatant was pretreated with wavelet denoising method and the correlation model was established between NIR spectra and chemical oxygen demand (COD) using iternative partial least squares(iPLS) method. Results showed that the correlation coefficients of the model was 0.9786 and root mean square errors of cross validation (RMSECV)of the model was 39.13. The variables could be decreased and the operation time could be shortened using the wavelet denoising pretreatment combined with iPLS method, and the prediction accuracy could also be increased, which provides a feasible and rapid method for the COD determination of the supernatants during the sludge fermentation process.