Start-up of oxygen-limited autotrophic partial nitrification-anammox process for treatment of nitrite-free wastewater in a single-stage hybrid bioreactor

Assessment of the start-up of the passive aeration simultaneous nitrification and denitrification (PASND) process using activated sludge as a sole seed for low-energy C and N removal

“…Each reactor was filled with about 30% ( V carriers / V reactor ) polyethylene biocarriers (φ25 × 10 mm and surface area of >600 m 2 m −3 ) as used in the previous studies. 19 A mixture of zeolite-activated sludge was prepared by adding 40 g of zeolite into 1 L activated sludge (VSS = 6700 mg L −1 , collected from Zhenjiang Wastewater Treatment Plant, Jiangsu Province, China) followed with thorough mixing. A total volume of 2 L of this mixture was repeatedly and continuously loaded onto the biocarrier from the top for 48 h until more than 90% of the suspended solids (biomass and zeolite powder) were stuck to the biocarrier.…”

“…4a, during the anaerobic phase, the concentration of COD (i.e. acetate) gradually decreased to 0 mg L −1 , followed by the PHAs content increasing to 19 The transformation stoichiometry for carbon compounds was calculated. The anaerobic PHAs produced /VFA consumed ratio was 0.65 Cmmol/Cmmol, similar to the yields of sludge with a high abundance of Thauera and PHAs synthetic bacteria Environmental Science: Water Research & Technology Paper domesticated under SBR conditions, but lower than the values reported in some enriched GAO cultures.…”

Combining numerical simulation with response surface modelling for optimization of reject water partial nitritation/anammox in moving bed biofilm reactor

“…Similarly, Rosenvinkel and Cornelius [31] reported 80% removal efficiency gained in the full-scale MBBR system under DO up to 4 gO 2 /m 3 . Keeping DO between 0.9 and 1.2 gO 2 /m 3 allowed achieve high ammonium removal efficiency in a 'hybrid air-lift shaft reactor' with aerobic and anoxic zones [32]. In a completely mixed 'activated sludge/immobilized activated sludge' bioreactor with an additional treatment of recirculated activated sludge, optimal DO was determined at the lower level of 0.6 ± 0.2 gO 2 /m 3 [33].…”