Performance enhancement of SBR applying real-time control

This paper presents the applications of a real-time oxidation reduction pot ential (ORP) and pH control system to enhance the system performance of a c ontinuous-inflow sequencing batch reactor (SBR). The real-time controlled S BR showed better performances than sequential control regarding substrate r emoval efficiency and cost reduction. In substrate removal efficiency, good GOD, total Kjeldahl nitrogen, and NH4+ removals were achieved by real-time and conventional sequential controlled systems. However, the poor removal of total nitrogen caused by incomplete denitrification in the sequential co ntrolled SBR was improved significantly to 91% by real-time control. Moreov er, in contrast with sequential controlled SBR, the real-time controlled SB R can save 14-32% of aeration energy and 11-29% of reactor capacity. Observ ation of nitrogen compound variations showed nitrites accumulated during th e aerobic phase of the real-time controlled SBR. In addition, the kinetics of nitrification and denitrification also proved that the real-time control led SBR performed the nitrite-type nitrification, which was identified as t he key-point of system performance enhancement in the real-time controlled SBR.