Start-up of anaerobic fixed film reactors: technical aspects

• Published in: Water science and technology 1994-01, Vol.29 (10-11), p.297-308
• Main Authors: Austermann-Haun, U., Seyfried, C. F., Zellner, G., Diekmann, H.
• Format: Article
• Language: English
• Subjects: Anaerobic conditions; Butyric acid; Calcium; Dosage; Inoculum; Load distribution; Loading rate; Municipal wastewater; Organic loading; pH effects; Polypropylene; Reactors; Removal; Sludge; Sludge digestion; Substrata; Wastewater; Wastewater treatment; Wastewater treatment plants
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.1994.0773

For two years lab-scale experiments were done to find the conditions to enhance the start-up of anaerobic fixed film reactors. Five reactors were operated in parallel with a sythetic wastewater containing acetic, propionic and butyric acid in a weight relation of 2:1:1 resulting in a COD of 20,000 mg/l. Using polypropylene curlers (NOR-PAC R 92/1) as support medium (substratum) and mostly digested sludge of a municipal wastewater treatment plant as inoculum, we found that the activity of the starter culture, effluent recirculation, calcium dosage and the mode of increasing the organic loading rate had a significant influence on start-up behaviour. Depending on the way to run the start-up space loading rates of 10 to 30 g COD/(l·d) could be reached within 58 days. In contrast to these “manual” start-ups it is shown that the most efficient way is to run a start-up pH-statically with an automatic substrate feeding regulated by the pH measured in the top of the reactor. Within 36 days a space loading rate of 60 g COD/(l·d) with a COD removal efficiency of 70 % could be reached.