Abstract
The recovery of nutrients from wastewater and its valorization into single cell protein (SCP) is a promising approach to promote the transition of current economy into a circular economy. Acetate and NH4-N are both prevalent in anaerobic digestion (AD) effluent treating various agricultural and industrial wastes. The organic carbon and nitrogen source can be recycled as a feedstock for specific microorganisms, i.e. brewer’s yeast Saccharomyces cerevisiae, whose biomass is rich in protein and can be harvested as the
next-generation protein source for human beings.
In this study, a three-chamber electrodialysis cell (ED) was applied to simultaneously recover acetate and NH4-N from AD effluent.
The recovery was further concentrated as a feedstock for S.cerevisiae by a forward osmosis (FO) process. Using the recovered
nutrients from AD effluent, S. cerevisiae was incubated in serum bottles and finally harvested as SCP.
A higher voltage of ED within the range of 1-3 V could recover more acetate and NH4-N, however, exhibited lower current efficiency
due to some electrochemical side reactions. At 2 V, 4.5 g/L acetate and 0.76 g/L NH4-N were reclaimed into the middle chamber, accounting for 42.2% and 60.1% of the raw AD effluent. In the FO process, acetate and NH4-N were enriched by 14 and 10 times along with undesired Cl- permeation into the recovery. The amino acids of S. cerevisiae’s SCP were consistent with rich leucine, lysine, threonine, and valine, above the FAO recommendation as a high-quality protein by 2.1, 4.2, 3.8, and 1.6-fold. The energy cost of the entire recovering process was mostly derived from the pump of FO. When a single ED recovering system was applied without further concentration by the FO process, 7143 L AD effluent was required to produce 1 kg SCP and the total operation
cost of manufacturing SCP was €20.4/kg SCP.
This work for the first time proved the feasibility of SCP generation by brewer’s yeast S. cerevisiae using the recycled nutrients from AD effluent. Acetate and NH4-N were simultaneously extracted from AD effluent and the operation cost of manufacturing SCP was competitive with the current SCP products on the market. The results revealed that AD effluent could be a valuable nutrient sink for sustainable SCP generation by S. cerevisiae.
next-generation protein source for human beings.
In this study, a three-chamber electrodialysis cell (ED) was applied to simultaneously recover acetate and NH4-N from AD effluent.
The recovery was further concentrated as a feedstock for S.cerevisiae by a forward osmosis (FO) process. Using the recovered
nutrients from AD effluent, S. cerevisiae was incubated in serum bottles and finally harvested as SCP.
A higher voltage of ED within the range of 1-3 V could recover more acetate and NH4-N, however, exhibited lower current efficiency
due to some electrochemical side reactions. At 2 V, 4.5 g/L acetate and 0.76 g/L NH4-N were reclaimed into the middle chamber, accounting for 42.2% and 60.1% of the raw AD effluent. In the FO process, acetate and NH4-N were enriched by 14 and 10 times along with undesired Cl- permeation into the recovery. The amino acids of S. cerevisiae’s SCP were consistent with rich leucine, lysine, threonine, and valine, above the FAO recommendation as a high-quality protein by 2.1, 4.2, 3.8, and 1.6-fold. The energy cost of the entire recovering process was mostly derived from the pump of FO. When a single ED recovering system was applied without further concentration by the FO process, 7143 L AD effluent was required to produce 1 kg SCP and the total operation
cost of manufacturing SCP was €20.4/kg SCP.
This work for the first time proved the feasibility of SCP generation by brewer’s yeast S. cerevisiae using the recycled nutrients from AD effluent. Acetate and NH4-N were simultaneously extracted from AD effluent and the operation cost of manufacturing SCP was competitive with the current SCP products on the market. The results revealed that AD effluent could be a valuable nutrient sink for sustainable SCP generation by S. cerevisiae.
Original language | English |
---|---|
Publication date | 2022 |
Number of pages | 1 |
Publication status | Published - 2022 |
Event | 8th International Society for Microbial Electrochemistry and Technology Global Conference: ISMET8 - Crete, Greece, Chania, Greece Duration: 19 Sept 2022 → 23 Sept 2022 Conference number: 8 https://www.ismet8.org/en/home |
Conference
Conference | 8th International Society for Microbial Electrochemistry and Technology Global Conference |
---|---|
Number | 8 |
Location | Crete, Greece |
Country/Territory | Greece |
City | Chania |
Period | 19/09/2022 → 23/09/2022 |
Internet address |