Publications by authors named "Youl Han"

This study coupled anaerobic digestion with vacuum stripping to achieve stable digestion at higher organic loading rates. Besides mitigation of ammonia inhibition, vacuum stripping of digestate improves solids solubilization and dewaterability due to vacuum-enhanced low-temperature thermal and mild-alkaline treatment under the vacuum stripping conditions (65 °C, 25-27 kPa, and pH 9). Batch vacuum stripping for 8 h removed 97.

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Ammonia can be accumulated to a level inhibitory to methanogenesis. There are large discrepancies in the reported inhibition thresholds. Through extended batch digestion experiments (up to 110 d) at 6 ammonia concentrations (0.

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Anaerobic digestion is a technology that simultaneously treats waste and generates energy in the form of biogas. Unfortunately, when a high organic loading rate is applied, anaerobic digestion can suffer from volatile fatty acid accumulation that results in pH drop and decreased biogas production. In particular, propionic acid has shown to inhibit biogas production even at a very low concentration.

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Simultaneous nitritation/anammox and nitrification/denitrification (SNAND) is a promising method to increase nitrogen removal from ammonium- and nitrate-rich wastewater. This study examined the effects of influent nitrogen concentrations on plant assimilation and microbial nitrogen removal via SNAND in three free water surface wetlands. Anammox and denitrification contributed 78 and 22%, respectively, of microbial removal of total inorganic nitrogen (TIN).

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