The immobilized Alcaligenes faecalis strain WT14 for removing high strength nitrate and reducing nitrite accumulation.
Environ Technol
; 43(1): 131-138, 2022 Jan.
Article
in En
| MEDLINE
| ID: mdl-32508276
ABSTRACT
Microbial immobilization is considered as one of the effective denitrification techniques in the treatment of high load wastewater. In this study, the immobilized cells consisting of polyvinyl alcohol (PVA), sodium alginate (SA), and calcium chloride (CaCl2) were inoculated with Alcaligenes faecalis strain WT14 to treat wastewater with high nitrate-nitrogen (NO3--N) concentrations. After 48â
h of wastewater treatment, 26.2-89.4% of total nitrogen (TN) was removed by the immobilized Alcaligenes faecalis strain WT14. The response surface methodology revealed the highest TN removal efficiency by Alcaligenes faecalis strain WT14 occurred at the immobilized ratio of 9.3% of PVA, 2.2% of SA and 1.9% of CaCl2. Under the optimal ratio of PVA, SA, and CaCl2, the conditions for the maximum denitrification efficiency and TN removal were pH of 7, temperature of 40°C, and shaking speed of 60â
rpm·min-1. Compared to the free cells, the immobilization cells had no obvious negative effect on denitrification efficiency, additionally reduced the nitrite accumulation, and thus improved the TN removal. Furthermore, the immobilized cells still maintained 95.4% of NO3--N removal after the eighth cycle reuse. These results demonstrated the immobilized Alcaligenes faecalis strain WT14 can remove TN effectively and additionally reduce nitrite accumulation in treating high strength NO3--N wastewater.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Alcaligenes faecalis
/
Nitrites
Language:
En
Journal:
Environ Technol
Journal subject:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Year:
2022
Document type:
Article