MERINO: Maximizing energy recovery through innovative nitrogen removal

This project aims to transform wastewater treatment plants (WWTPs) from a large energy consumer to a net renewable energy exporter by developing innovative technologies to enable maximum energy recovery from wastewater while achieving excellent pollutant removal.

The current wastewater treatment practice consumes a large amount of electricity to aerobically oxidize the organic matter in wastewater, and hence destroying the chemical energy embedded. The need for a paradigm shift from an energy-consuming wastewater treatment process to an energy recovery process has been recognised by the wastewater industry. Through substantial laboratory works The project team has developed innovative technologies, including: (1) a technology to enhance anaerobic methane production based on sludge pre-treatment using free nitrous acid (FNA or HNO­2), (2) a technology to selectively suppress the growth of NOB in the nitritation reactor using FNA to achieve stable partial nitritation (FNA project), (3) a technology to augment nitrogen removal in the by coupling Anammox and DAMO microorganisms (DAMO project). We will demonstrate the process design and those technologies with the use of three pilot plants located in Queensland, South Australia and Washington DC, respectively.

Funding

• Industrial Partners

Collaborators

• DC Water for Life
• Melbourne Water
• Urban Utilities
• SA Water
• Sydney Water

Project Outcomes

Laboratory experimental results showed that stable partial nitritation could be achieved through side-stream sludge treatment using FNA at 1.83 mg N/L. 

Publications

Papers

• Xueming Chen, Jianhua Guo, Guo-Jun Xie, Zhiguo Yuan, Bing-Jie Yuan. Achieving complete nitrogen removal by coupling nitritation-anammox and methane-dependent denitrification: A model-based study. Biotechnology and Bioengineering, 2016, DOI:10.1002/bit.25866.
• Jianhua Guo, Liang Zhang, Lu Fan, Bing-Jie Ni, Boran Kartal, Yongzhen Peng, Mike S.M. Jetten, Zhiguo Yuan. Metagenomic analysis of anammox community structure in three different microbial aggregates. Environmental Microbiology, 2016, DOI: 10.1111/1462-2920.13132.
• Wang, Q., Hao, X., Yuan, Z. (2016). Towards energy positive wastewater treatment by sludge treatment using free nitrous acid. Chemosphere, 144, 1869-1873.