IWA Publishing
 IWA Publishing Journals   Subscriptions   Authors   Users   Librarians   FAQs 

Water Science & Technology—WST Vol 58 No 1 pp 83–87 © IWA Publishing 2008 doi:10.2166/wst.2008.648

A membrane biofilm reactor achieves aerobic methane oxidation coupled to denitrification (AME-D) with high efficiency

O. Modin, K. Fukushi, F. Nakajima and K. Yamamoto

Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan oskar@env.t.u-tokyo.ac.jp
Integrated Research System for Sustainability Science (IR3S), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan
Environmental Science Center, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


ABSTRACT

Methane would potentially be an inexpensive, widely available electron donor for denitrification of wastewaters poor in organics. Currently, no methanotrophic microbe is known to denitrify. However, aerobic methane oxidation coupled to denitrification (AME-D) has been observed in several laboratory studies. In the AME-D process, aerobic methanotrophs oxidise methane and release organic metabolites and lysis products, which are used by coexisting denitrifiers as electron donors for denitrification. Due to the presence of oxygen, the denitrification efficiency in terms of methane-to-nitrate consumption is usually low. To improve this efficiency the use of a membrane biofilm reactor was investigated. The denitrification efficiency of an AME-D culture in (1) a suspended growth reactor, and (2) a membrane biofilm reactor was studied. The methane-to-nitrate consumption ratio for the suspended culture was 8.7. For the membrane-attached culture the ratio was 2.2. The results clearly indicated that the membrane-attached biofilm was superior to the suspended culture in terms of denitrification efficiency. This study showed that for practical application of the AME-D process, focus should be placed on development of a biofilm reactor.

Keywords: biofilm; denitrification; membrane; methanotrophs


Full article (PDF Format)


eProduct: Buy this article for £24.00 (IWA MEMBER PRICE: £18.00)
All prices include VAT. For customers where VAT should not be applied, the VAT amount will be removed upon payment