Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4762777 | Chemical Engineering Journal | 2018 | 10 Pages |
â¢We propose a strategy for on-line estimation of the nitrification phase duration.â¢Estimation of nitrification phase duration depends on real-time measurements of both pH and dissolved oxygen.â¢We use feature extraction and support vector machines to solve the on-line estimation problem.â¢A database of 533 SBR cycles was used to train and test the proposed strategy.â¢We achieve 100% correct classification for both training and testing databases.
We present a strategy for the on-line estimation of the aerobic reaction phase length for a partial nitrification process with pH and dissolved oxygen closed-loop control. To overcome existing drawbacks associated to partial nitrification (e.g., non-linearities and time-variant behaviors), our strategy is based on feature extraction over manipulated variables to identify interesting patterns associated to the end-point of nitrification. We use a support vector machine (SVM) classifier as a decision tool to determine the end-point of the aerobic phase. A database of lab-scale sequencing batch reactor (SBR) cycles selected from ten months of operation was used to train and test the proposed decision-making strategy. Results for all 533 SBR cycles showed 100% correct classifications. Most aerobic phase lengths in the analyzed database had a reduction time around 20Â min, although time reductions greater than 60Â min were also achieved.