Nutrients recycle and the growth of Scenedesmus obliquus in synthetic wastewater under different sodium carbonate concentrations

Abstract

This study illustrated the growth of Scenedesmus obliquus and recycle of nutrients in wastewater combined with inorganic carbon under autotrophic conditions. Scenedesmus obliquus was cultivated under different conditions by adding sodium carbonate (Na 2 CO 3 ) at 15–40 mg l −1 separately in wastewater containing high nitrogen and phosphorus content. The growth characteristics of S. obliquus , pH and dissolved inorganic carbon (DIC) changes of microalgae liquid, the recycle rate of ammonia and phosphorus and lipid content were determined. The changes of pH and DIC showed that S. obliquus could use Na 2 CO 3 to grow, with lipid contents of 18–25%. Among all Na 2 CO 3 concentrations, 20 mg l −1 was the optimum, of which S. obliquus had the highest NH 3 -N recycle of 52% and P O 4 3 – P recycle of 67%. By the 14th day, its biomass production also reaches the maximum of 0.21 g l −1 . However, inorganic carbon fixation rate was inversely proportional to its concentration. Moreover, the biomass was in positive correlation with the Na 2 CO 3 concentration except 20 mg l −1 , which provided a possibility that S. obliquus could be acclimatized to adjust to high concentrations of inorganic carbon to promote biomass accumulation and recycle of nutrients.

Mutual impacts and interactions of antibiotic resistance genes, microcystin synthetase genes, graphene oxide, and Microcystis aeruginosa in synthetic wastewater

“…It indicated that hormesis mechanism would be triggered in M. aeruginosa and ARGs abundance when the GO presents. The presence of GO at finite concentration in aquatic environment can aggravate the harm of M. aeruginosa and spread of ARGs (Duan et al 2020.…”

Effects of simultaneous CO2 addition and biomass recycling on growth characteristics of microalgal mixed culture

“…4,7 Several microalgae species have been reported to have the capability for CO 2 fixation and also to grow in urban wastewaters among which Scenedesmus obliquus and Chlorella vulgaris are the most promising candidates. [8][9][10][11][12] Su et al 13 compared the nutrient removal efficiency of high-potential microalgae species C. vulgaris and Scenedesmus rubescens cultivated in secondary effluent urban wastewater, and reported nitrogen (N) and phosphorus (P) removal efficiencies of >99% for both microalgae species. Liu et al 14 evaluated the influence of CO 2 concentration from 1% to 20% on C. vulgaris in domestic wastewater, and determined a maximum microalgal biomass concentration of 1.12 g L −1 with 10% CO 2 as feed gas.…”

A novel nanoemulsion-based microalgal growth medium for enhanced biomass production

“…To overcome these limitations, chemical absorption of CO 2 has been considered in the past, which involves the addition of solvents like carbonates and amines. Duan et al [ 17 ], cultivated Scenedesmus obliquus in wastewater and obtained an increase in lipid content (from 16 to 25%) as well as biomass concentration (from ~ 0.13 to 0.21 g L −1 ) upon adding 20 mg L −1 sodium carbonate to the wastewater. Enhanced protein (67.1 mg L −1 d −1 ) and lipid (46.9 mg L −1 d −1 ) productivity were obtained by adding monoethanolamine during the fed-batch cultivation of Chlorella fusca LEB 111 although the biomass productivity was found to be similar to the control [ 18 ].…”