Performance, carotenoids yield and microbial population dynamics in a photobioreactor system treating acidic wastewater: Effect of hydraulic retention time (HRT) and organic loading rate (OLR).
Effects of hydraulic retention time (HRT) and influent organic loading rate (OLR) were investigated in a photobioreactor containing PNSB (Rhodopseudomonas palustris)-chemoheterotrophic bacteria to treat volatile fatty acid wastewater. Pollutants removal, biomass production and carotenoids yield in different phases were investigated in together with functional microbial population dynamics. The results indicated that properly decreasing HRT and increasing OLR improved the nutrient removal performance as well as the biomass and carotenoids productions. 85.7% COD, 89.9% TN and 91.8% TP removals were achieved under the optimal HRT of 48h and OLR of 2.51g/L/d. Meanwhile, the highest biomass production and carotenoids yield were 2719.3mg/L and 3.91mg/g-biomass respectively. In addition, HRT and OLR have obvious impacts on PNSB and total bacteria dynamics. Statistical analyses indicated that the COD removal exhibited a positive relationship with OLR, biomass and carotenoids production. PNSB/total bacteria ratio had a positive correlation with the carotenoids yield.
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Shuli
S
Liu
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China; School of Environment and Resource, Renmin University of China, Beijing 100872, China. Electronic address: zgm@ruc.edu.cn.
Guangming
G
Zhang
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Jie
J
Zhang
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Xiangkun
X
Li
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Jianzheng
J
Li
D018533:Biomass; D002338:Carotenoids / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D058433:Photobioreactors / Q000382:microbiology*; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
D002338:Carotenoids; D005232:Fatty Acids, Volatile; D062065:Wastewater
Acidic wastewater; Carotenoids yield; Hydraulic retention time; Organic loading rate; Photobioreactor