Growth of microalgae in diluted process water of the animal wastewater treatment plant

Abstract

The growth of microalgae was investigated using diluted process water from an animal waste treatment plant as a substrate. Batch experiments were carried out to determine the growth characteristics of three microalgae strains: Microcystis aeruginosa, Chlorella vulgaris and Euglena gracilis. The two types of process water with different dilution rates were used for the experiments. The biokinetic parameters of each culture were estimated from the logistic growth curves for comparative analysis. In aerobic effluent, most growth parameters were significantly better than in anaerobic effluent regardless of the dilution rates. This suggests that the concentration of organic matter, such as volatile fatty acids, affects microgal growth. Euglena gracilis, which was the largest in size, had the highest growth rates among the three species in both pure and mixed cultures.

The transcriptome of Euglena gracilis reveals unexpected metabolic capabilities for carbohydrate and natural product biochemistry

“…85% of its' dry weight. These compounds are produced even under adverse conditions such as those encountered in acid mine drains, 11 which suggests potential for the use of this taxa in waste water management 12 and/or the production of biodiesel. In contrast, under anaerobic conditions wax esters 9,10 comprise over 50% of the dry weight of some strains of Euglena.…”

Control of nitrogen behaviour by phosphate concentration during microalgal-bacterial cultivation using digestate

“…However, nitrogen or phosphorus still can limit the recycling of the whole N and P pools. Indeed, most N:P ratios of anaerobic digestate from livestock waste vary from 3 to 30 g N-NH 4 gP À1 in literature (Cañizares-Villanueva et al, 1994;Park et al, 2009;Levine et al, 2011;Chen et al, 2012). The heterogeneity of N:P ratios in digestate is due to AD inputs for nitrogen and phosphorus, the anaerobic digestion process and its management but also, concerning phosphate, functions of separation processes and chemical properties of digestate during anaerobic digestion.…”

Utilization of secondary-treated wastewater for the production of freshwater microalgae

“…STWW also contained an excess of phosphorus with respect to the nitrogen content, although lower than that observed in Arnon medium. The N/P ratio for Arnon and STWW was 1 and 1.7, respectively; the ratio cited in the literature varied between 3 and 30 (Park et al 2009). In any case, Table 1 demonstrates that Arnon medium provided excess nutrients whereas STWW contained low nutrient concentrations; thus, we expect the cultures grown in this culture medium to be nutrient limited.…”