1.
[Cultivating an oleaginous microalgae with municipal wastewater].
Lü, S, Zhang, W, Peng, X, Chen, X, Liu, T
Sheng wu gong cheng xue bao = Chinese journal of biotechnology. 2011;(3):445-52
Abstract
Municipal wastewater is usually problematic for the environment. The process of oleaginous microalgal culture requires large amounts of nutrients and water. Therefore, we studied the feasibility of oleaginous microalgal culture of Scenedesmus dimorphus in bubbled column photobioreactor with municipal wastewater added with different nutrients. S. dimorphus could adapt municipal nutrient-rich wastewater by adding some nutrients as nitrogen, phosphorus, ferric ammonium citrate and trace elements, and the amounts of such nutrients have significant effects on cell growth, biomass yield and lipid accumulation. At optimum compositions of wastewater medium, the algal cell concentration could reach 8.0 g/L, higher than that of 5.0 g/L in standard BG11. Furthermore, S. dimorphus had strong capacity to absorb inorganic nitrogen and phosphorus from its culture water. There was almost no total nitrogen and phosphorus residues in culture medium after three or four days culturing when the adding mounts of nitrate and phosphate in wastewater medium were no more than 185.2 mg/L and 16.1 mg/L respectively under the experimental conditions. As a conclusion, it was feasible to cultivate oleaginous microalgae with municipal nutrient-rich wastewater, not only producing feedstock for algal biodiesel, but also removing inorganic nitrogen and phosphorus from wastewater.
2.
[Relation analysis of phosphorus removal and BOD5 loading using PHB monitoring in A2/O process].
Gao, S, Dai, XC, Chen, X, Gao, Y, Zhu, Y, Huang, Y, Huang, MS, Wang, GH
Huan jing ke xue= Huanjing kexue. 2008;(11):3093-7
Abstract
In a pilot-scale anaerobic-anoxic-oxic experimental system for municipal wastewater treatment, PHB consumption in an oxic tank and PHB production in an anaerobic tank had been monitored overtime, and relations among PHB consumption/production, phosphorus removal/release and BOD5 loading had been analyzed. The results indicated that the consumption of PHB was positively related with phosphorus removal, and about 140 mg PHB consumption could result in 1 mg P removal. In the anaerobic tank, about 1.17 mg P release could result in 100 mg PHB production. The PHB production at the loading of 0.176 g/(g x d) was 4 mg/g MLSS less than that at 0.413 g/(g x d). No significant relevance was observed between PHB and BOD5 removal. The PHB of microorganism synthesizes was increased with the increase of temperature. Compared with the lowest temperature (17.1 degrees C), 20% of the total PHB content was increased at the maximum temperature (33.2 degrees C) in active sludge.