TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Paulsen, Svea
A1  - Ott, Fabian
A1  - Grömping, Markus
T1  - Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant
JF  - Water and Environment Journal
N2  - The present work aimed to study the mainstream feasibility of the deammonifying sludge of side stream of municipal wastewater treatment plant (MWWTP) in Kaster, Germany. For this purpose, the deammonifying sludge available at the side stream was investigated for nitrogen (N) removal with respect to the operational factors temperature (15–30°C), pH value (6.0–8.0) and chemical oxygen demand (COD)/N ratio (≤1.5–6.0). The highest and lowest N-removal rates of 0.13 and 0.045 kg/(m³ d) are achieved at 30 and 15°C, respectively. Different conditions of pH and COD/N ratios in the SBRs of Partial nitritation/anammox (PN/A) significantly influenced both the metabolic processes and associated N-removal rates. The scientific insights gained from the current work signifies the possibility of mainstream PN/A at WWTPs. The current study forms a solid basis of operational window for the upcoming semi-technical trails to be conducted prior to the full-scale mainstream PN/A at WWTP Kaster and WWTPs globally.
KW  - Anammox
KW  - Mainstream
KW  - Nitrogen removal
KW  - Partial nitritation
KW  - Wastewater
Y1  - 2023
U6  - http://dx.doi.org/10.1111/wej.12898
SN  - 1747-6593
N1  - Corresponding author: Dheeraja Cheenakula
IS  - Early View
SP  - 1
EP  - 12
PB  - Wiley
CY  - Chichester
ER  - 
TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Griebel, Kai
A1  - Montag, David
A1  - Grömping, Markus
ED  - Huang, Xiaowu
T1  - Concept development of a mainstream deammonification and comparison with conventional process in terms of energy, performance and economical construction perspectives
JF  - Frontiers in Microbiology
N2  - Deammonification for nitrogen removal in municipal wastewater in temperate and cold climate zones is currently limited to the side stream of municipal wastewater treatment plants (MWWTP). This study developed a conceptual model of a mainstream deammonification plant, designed for 30,000 P.E., considering possible solutions corresponding to the challenging mainstream conditions in Germany. In addition, the energy-saving potential, nitrogen elimination performance and construction-related costs of mainstream deammonification were compared to a conventional plant model, having a single-stage activated sludge process with upstream denitrification. The results revealed that an additional treatment step by combining chemical precipitation and ultra-fine screening is advantageous prior the mainstream deammonification. Hereby chemical oxygen demand (COD) can be reduced by 80% so that the COD:N ratio can be reduced from 12 to 2.5. Laboratory experiments testing mainstream conditions of temperature (8–20°C), pH (6–9) and COD:N ratio (1–6) showed an achievable volumetric nitrogen removal rate (VNRR) of at least 50 gN/(m3∙d) for various deammonifying sludges from side stream deammonification systems in the state of North Rhine-Westphalia, Germany, where m3 denotes reactor volume. Assuming a retained Norganic content of 0.0035 kgNorg./(P.E.∙d) from the daily loads of N at carbon removal stage and a VNRR of 50 gN/(m3∙d) under mainstream conditions, a resident-specific reactor volume of 0.115 m3/(P.E.) is required for mainstream deammonification. This is in the same order of magnitude as the conventional activated sludge process, i.e., 0.173 m3/(P.E.) for an MWWTP of size class of 4. The conventional plant model yielded a total specific electricity demand of 35 kWh/(P.E.∙a) for the operation of the whole MWWTP and an energy recovery potential of 15.8 kWh/(P.E.∙a) through anaerobic digestion. In contrast, the developed mainstream deammonification model plant would require only a 21.5 kWh/(P.E.∙a) energy demand and result in 24 kWh/(P.E.∙a) energy recovery potential, enabling the mainstream deammonification model plant to be self-sufficient. The retrofitting costs for the implementation of mainstream deammonification in existing conventional MWWTPs are nearly negligible as the existing units like activated sludge reactors, aerators and monitoring technology are reusable. However, the mainstream deammonification must meet the performance requirement of VNRR of about 50 gN/(m3∙d) in this case.
KW  - anammox
KW  - energy efficiency
KW  - mainstream deammonification
KW  - nitrogen elimination
KW  - wastewater
Y1  - 2023
U6  - http://dx.doi.org/10.3389/fmicb.2023.1155235
SN  - 1664-302X
VL  - 14
IS  - 11155235
SP  - 1
EP  - 15
PB  - Frontiers
ER  -