Repozytorium publikacji - Politechnika Gdańska

The activated sludge process of the digestate liquors after chemical separation was conducted using a 10 L lab-scale sequencing batch reactor (SBR) and a 0.50 m3 pilotscale SBR independently (with pH control). Due to the relatively high concentration of free ammonia (FA), clear inhibitory effects of the digestate liquors on the nitrifying bacteria were observed. The adaptation of the activated sludge to the toxicity was evaluated with the trends of ammonia uptake rate (AUR) and nitrate utilization rate (NUR). The lab-scale AUR values decreased from 5.3 to 2.6 g N/(kg VSS·h) over time after the addition of digestate liquors (5–10% of the reactor working volume), indicating an apparent FA inhibition on the nitrification process in the FA concentration range of 0.3–0.5 mg N/L. The pilot-scale AUR values increased from 1.8 to 3.6 g N/ (kg VSS·h) in the first two weeks and then decreased to 2.4 g N/(kg VSS·h), showing a lag of the inhibition on the nitrifying bacteria at the FA concentration ≈ 0.15 mg N/L. The lab-scale NURs increased from 2.6 to 10.4 g N/(kg VSS·h) over time, and the pilot-scale NURs increased from 1.0 to 4.0 g N/(kg VSS·h) in a similar pattern. The clear dependence of both the lab- and pilot-scale NURs on time indicated the adaptation of the heterotrophic biomass to the digestate liquors. Ethanol – used instead of fusel oil – was found to be a more efficient external carbon source for better adaptation of the activated sludge under unfavorable conditions.

Autorzy

• dr inż. Joanna Majtacz link otwiera się w nowej karcie ,
• dr inż. Przemysław Kowal link otwiera się w nowej karcie ,
• inż. Lu Xi,
• dr inż. Hussein Al-Hazmi link otwiera się w nowej karcie ,
• prof. dr hab. inż. Jacek Mąkinia link otwiera się w nowej karcie