TY - JOUR N2 - A new method for measurement of sludge blanket height (SBH) based on image analysis is presented. The proposed method uses a histogram back-projection algorithm to distinguish between the settling sludge and supernatant and can be used with sludge possessing different coloring characteristics both in the sludge color and the color of supernatant produced. Individual pixels in the acquired image are compared with a histogram of a representative sludge region. Therefore, the proposed method relies neither on the assumed shape of light intensity profile nor on the dominant sludge or supernatant color. Batch sedimentation tests are presented for different initial sludge concentrations and different background colors to simulate different sludge characteristics. Parameters of a settling velocity function are estimated based on the obtained results. Additionally, an algorithm is proposed that enables the zone settling velocity (ZSV) to be estimated before the batch sedimentation test is completed. L1 - http://journals.pan.pl/Content/119077/PDF/29_01580_Bpast.No.69(1)_17.01.21_K1_A.pdf L2 - http://journals.pan.pl/Content/119077 PY - 2021 IS - No. 1 EP - e136187 DO - 10.24425/bpasts.2021.136187 KW - batch sedumentation test KW - activated sludge KW - image analysis KW - control of recycle in WWTPs A1 - Nocoń, Witold A1 - Pośpiech, Jakub A1 - Kopciński, Jacek VL - 69 DA - 26.01.2021 T1 - Automatic batch sedimentation test based on histogram back-projection image analysis SP - e136187 UR - http://journals.pan.pl/dlibra/publication/edition/119077 T2 - Bulletin of the Polish Academy of Sciences Technical Sciences ER -