This study investigated biocoagulation of dairy process wastewater with a new system of the microaerobic sequencing batch reactor (micro-aerobic SBR) at a batch bench scale.Lactobacillus caseiTISTR
1500 was inoculated to produce acid coagulants under non-sterile acid conditions. Colloidal proteins
were removed by employing a solid–liquid separation step as a pre-treatment. The micro-aerobic SBR
process had the efficiencies of organic reduction with 73.65.9%, 90.11.3%, and 85.70.6% of chemical
oxygen demand (COD), proteins, and sugars without adding external coagulant, and flocculant, respectively.
Sustained acid fermentation was achieved for at least 150 cycles by applying an indigenous fill-react-settledraw-idle sequence in the micro-aerobic SBR process and the use of different solid retention times at 3, 6, 9,
12 and 15 d, consecutively. The micro-aerobic SBR system was able to support lactic acid bacteria (LAB)
growth with long SRT (12 and 15 d), due to at least 3 factors: the large inoculum size employed, relatively
high concentration of lactic acid produced, and the change in pH during the restoring stage. Current process
offered a possible alternative to the more costly chemical and other biological pre-treatments