Swine wastewater, containing a high concentration of COD and ammonia nitrogen, is suitable for the
growth of microalgae, leading to simultaneous COD/nutrients removal from the wastewater. In this
study, an isolated carbohydrate-rich microalga Chlorella vulgaris JSC-6 was adopted to perform swine
wastewater treatment. Nearly 60–70% COD removal and 40–90% NH3-N removal was achieved in the
mixotrophic and heterotrophic culture, depending on the dilution ratio of the wastewater, while the
highest removal percentage was obtained with 20-fold diluted wastewater. Mixotrophic cultivation by
using fivefold diluted wastewater resulted in the highest biomass concentration of 3.96 g/L. The carbohydrate
content of the microalga grown on the wastewater can reach up to 58% (per dry weight). The results
indicated that the microalgae-based wastewater treatment can efficiently reduce the nutrients and COD
level, and the resulting microalgal biomass had high carbohydrate content, thereby having potential
applications for the fermentative production of biofuels or chemicals.