Publications by authors named "Yunhui Pu"

Lactic acid (LA) is a crucial chemical which has been widely used for industrial application. Microbial fermentation is the dominant pathway for LA production and has been regarded as the promising technology. In recent years, many studies on LA production from various organic wastes have been published, which provided alternative ways to reduce the LA production cost, and further recycle organic wastes.

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Recycling of construction and demolition wastes contributes to achieve carbon summit and carbon neutrality early in the construction industry. Accelerated carbonation is a promising new technology for enhancing the properties of recycled concrete aggregates (RCAs) as well as mitigating global warming. This study performed a comparative life cycle assessment on RCAs modified by accelerated carbonation treatment and traditional methods.

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Caproic acid (CA) production from food waste (FW) is a promising way for waste recycling, while the fermentation processes need further exploration. In this study, FW acidogenic fermentation under different pH (uncontrolled, 4, 5, 6) using indigenous microbiota was investigated. Result showed that substrate hydrolysis, carbohydrate degradation and acidogenesis increased with the increase of pH.

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Article Synopsis
  • The study focused on improving methane production and reducing pollutants from swine wastewater using an anaerobic dynamic membrane bioreactor (AnDMBR) combined with microalgae cultivation.
  • Results indicated that reducing the hydraulic retention time (HRT) from 20 days to 10 days boosted methane production, but dropping it to 5 days decreased it significantly.
  • The microalgae effectively removed ammonia and phosphate, achieving the best biomass and lipid production with a 20% digestate ratio, but high digestate concentrations negatively affected growth.
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Article Synopsis
  • The study focused on understanding how membrane fouling occurs in anaerobic membrane bioreactors (AnMBR) when treating swine wastewater at various organic loading rates (OLR).
  • Results indicated that AnMBR effectively removes pollutants and produces energy, but higher OLR leads to worse fouling due to sludge and organic matter buildup.
  • Microbial analysis revealed that increased OLR causes a change in bacterial communities, particularly the growth of fouling-related bacteria, while backwashing can help restore membrane efficiency.
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The present study introduced a new method for enhanced biomethane production and pollution control of swine wastewater (SW) using anaerobic membrane bioreactor (AnMBR). Results confirmed 35 °C as the optimum temperature for enhanced anaerobic digestion which resulted in relatively higher methane production rate and potential. In AnMBR system, robust pollutants removal and conversion rate were achieved under various hydraulic retention time (HRT) ranging from 20 to 10 days, while the highest methane yield (0.

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Fermentation slurry from food waste (FSFW) produced at different temperatures (20, 37, and 55 °C) was utilized as external carbon source for promoting nitrogen removal in this study. It was found that high temperatures improved the hydrolysis rate by promoting the hydrolytic enzyme activity. Mesophilic temperature (37 °C) was favorable for organic acid (especially lactic acid) production by selectively enriching the Lactobacillus (with a relative abundance of 90.

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Fermentation slurry from food waste (FSFW) generated by acidogenic fermentation at mesophilic temperature was utilized to improve the nutrients removal from wastewater. Organic acids (such as lactate and volatile fatty acids) in the FSFW behaved as readily biodegradable carbon sources, while the particulate and macromolecular organics acted as slowly biodegradable carbon sources during denitrification processes. The FSFW dosage significantly influenced the nitrogen removal performance, and a C/N ratio (in terms of chemical oxygen demand to nitrogen ratio) of 8 could achieve complete denitrification in the batch tests.

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Enhancement of nitrogen and phosphate removal using thermophilic fermentation slurry from food waste (FSFW) as external carbon source was investigated. Based on the batch tests, the soluble and particulate fractions of the FSFW acted as easily and slowly biodegradable carbon sources, respectively, and the fermented slurry showed the combined nutrients removal properties of soluble and solid organics. During the long-term operation of a sequencing batch reactor (SBR) with FSFW for wastewater treatment, the sludge particle size increased obviously, the bacterial metabolic capacity improved significantly, and some functional microorganisms were enriched selectively, which significantly promoted the nitrogen removal efficiency (approximately 90%) by enhancing the anoxic denitrification and simultaneous nitrification and denitrification (SND) processes.

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In this study, nitrogen removal using the lactic acid fermentation products from food waste and other external chemical carbon sources (sodium acetate, sodium lactate and starch) was investigated. Similar to sodium acetate and lactate, the lactic acid-enriched fermentation liquid from food waste (FLFW) exhibited a high denitrification rate (5.5 mg NO-N/(g-VSS h)) and potential (0.

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