Techno-economic analysis of sidestream ammonia removal technologies

Techno-economic analysis of sidestream ammonia removal technologies: Biological options versus thermal stripping

Ochs, Pascal (Cranfield University; Thames Water Utilities Ltd.)
Martin, Ben (Thames Water Utilities Ltd.)
Germain-Cripps, Eve (Thames Water Utilities Ltd.)
Stephenson, Tom (Cranfield University)
van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology)
Soares, Ana (Cranfield University)

2023

Over the past twenty years, various commercial technologies have been deployed to remove ammonia (NH₄–N) from anaerobic digestion (AD) liquors. In recent years many anaerobic digesters have been upgraded to include a pre-treatment, such as the thermal hydrolysis process (THP), to produce more biogas, increasing NH₄–N concentrations in the liquors are costly to treat. This study provides a comparative techno-economic assessment of sidestream technologies to remove NH₄–N from conventional AD and THP/AD dewatering liquors: a deammonification continuous stirred tank reactor (PNA), a nitrification/denitrification sequencing batch reactor (SBR) and thermal ammonia stripping process with an ammonia scrubber (STRIP). The SBR and PNA were based on full-scale data, whereas the STRIP was designed using a computational approach to achieve NH₄–N removals of 90–95%. The PNA presented the lowest whole-life cost (WLC) over 40 years, with £7.7 M, while the STRIP had a WLC of £43.9 M. This study identified that THP dewatering liquors, and thus a higher ammonia load, can lead to a 1.5–3.0 times increase in operational expenditure with the PNA and the SBR. Furthermore, this study highlighted that deammonification is a capable and cost-effective nitrogen removal technology. Processes like the STRIP respond to current pressures faced by the water industry on ammonia recovery together with targets to reduce nitrous oxide emissions. Nevertheless, ammonia striping-based processes must further be demonstrated in WWTPs and WLC reduced to grant their wide implementation and replace existing technologies.

Deammonification
Denitrification
Nitrification
Sludge dewatering liquors
Wastewater

http://resolver.tudelft.nl/uuid:728312a7-2249-46df-bf5b-7b86543a9e5d

https://doi.org/10.1016/j.ese.2022.100220

Environmental Science and Ecotechnology, 13

Institutional Repository

journal article

© 2023 Pascal Ochs, Ben Martin, Eve Germain-Cripps, Tom Stephenson, Mark C.M. van Loosdrecht, Ana Soares