Detection of Equipment Faults at Sequencing Batch Reactor Using Dynamic Time Warping

동적시간와핑을 이용한 연속회분식 반응기의 장비고장 감지

  • Kim, Yejin (Department of Environmental Engineering, Catholic University of Pusan)
  • 김예진 (부산가톨릭대학교 환경공학과)
  • Received : 2016.01.26
  • Accepted : 2016.02.26
  • Published : 2016.04.30


The biological wastewater treatment plant, which uses microbial community to remove organic matter and nutrients in wastewater, is known as its nonlinear behavior and uncertainty to operate. Therefore, operation of the biological wastewater treatment process much depends on observation and knowledge of operators. The manual inspection of human operators is essential to manage the process properly, however, it is impossible to detect a fault promptly so that the process can be exposed to improper condition not securing safe effluent quality. Among various process faults, equipment malfunction is critical to maintain normal operational state. To detect equipment faults automatically, the dynamic time warping was tested using on-line oxidation-reduction potential (ORP) and dissolved oxygen (DO) profiles in a sequencing batch reactor (SBR), which is a type of wastewater treatment process. After one cycle profiles of ORP and DO were measured and stored, they were warped to the template profiles which were prepared already and the distance result, accumulated distance (D) values were calculated. If the D values were increased significantly, some kinds of faults could be detected and an alarm could be sent to the operator. By this way, it seems to be possible to make an early detecting of process faults.


Supported by : 한국연구재단


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