Domestic wastewater treatment using biological aerated filtration system with modified zeolite as biofilm support

Abstract

Modified zeolite and natural clinoptilolite were applied to treat domestic wastewater in two two-stage up-flow biological aerated filters (BAF) to compare their abilities to act as biofilm supports. The results showed that the two-stage BAF with modified zeolite brought a relative superiority to natural clinoptilolite two-stage BAF in terms of chemical oxygen demand and ammonia nitrogen removal under the conditions of temperature 20–26°C and dissolved oxygen above 4.00 mg l⁻¹. In addition, the detection of the amount of heterobacteria and nitrobacteria of two two-stage BAFs also showed that modified zeolite medium was more suitable to the attached growth of nitrobacteria, which is helpful to the improvement of nitrification performance in two-stage BAF with modified zeolite.

Keywords:

• Modified zeolite
• Biological aerated filter
• Start-up
• Ammonia nitrogen
• CODcr

Acknowledgements

This work was funded by the Natural Science Foundation of Shandong Province (ZR2012EEL21，ZR2011EEM003 and ZR2011EEM018), the Special Fund of Harbin Science & Technology Innovation Talents (for outstanding subject leaders, RC2013XK015009), and National Natural Science Foundation of China (NSFC51178207 and NSFC 50978121).