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To-Hung Tsui

Bio: To-Hung Tsui is an academic researcher from Hong Kong Baptist University. The author has contributed to research in topics: Medicine & Anaerobic digestion. The author has an hindex of 1, co-authored 1 publications receiving 60 citations.

Papers
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Journal ArticleDOI
01 Nov 2019
TL;DR: A critical review of various technologies, with their updated progress, involved in the exploitation of MSW as a renewable resource, along with the critical advantages and limitations on energy and material cycling for sustainable MSW management is presented in this article.
Abstract: Municipal solid waste (MSW) management has emerged as probably the most pressing issue many governments nowadays are facing. Traditionally, Waste-to-Energy(WtE) is mostly associated with incineration, but now, with the emergence of the bioeconomy, it embraces a broader definition comprising any processing technique that can generate electricity/heat or produce a waste-derived fuel. Under the ambit of the circular economy many nations are looking for, additional effort must be made to be sure of acquiring the most updated information and paving a sustainable path for managing MSW in such a frame. In this regard, we have undertaken a critical review of various technologies, with their updated progress, involved in the exploitation of MSW as a renewable resource, along with the critical advantages and limitations on energy and material cycling for sustainable MSW management. Incineration, the most widely used method, is nowadays difficult to further apply due to its dubious reputation and social opposition. Meanwhile, to address the organic fraction of MSW which currently is mostly unrecycled and causes disposal issues, the biological approach presents an attractive option. The new emphasis of bioeconomy leads us to understand how environmental biotechnologies should be better connected/integrated for more sustainable MSW management. This article is concluded with advances of future prospects, which can serve as a timely reminder to encourage competent authorities/researchers to work towards further improvement of the present MSW management system.

109 citations

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TL;DR: In this paper , a systematic investigation regarding how and to what extent can DIET-conductive materials (especially biochar) mitigate relevant anaerobic digestion (AD) away from the environmental burdens of hydrogen sulfide generation is provided.
Abstract: The sustainability of anaerobic digestion (AD) is often challenged by the low energy efficiency of sulfur-contaminated waste and subsequent high carbon emission in biogas desulfurization. Recent advances in the direct interspecies electron transfer (DIET) mechanism present a unique biotechnological means to cope with relevant fundamental constraints of microbial competition. This study aims to provide a systematic investigation regarding how and to what extent can DIET-conductive materials (especially biochar) mitigate relevant AD away from the environmental burdens of hydrogen sulfide generation. Through the experimental validation of biochar applications in bioreactor trials, the profiles of intermediates pathways and electron diversion were first examined together with microbiological analysis. Instead of suppressing the notorious growth of sulfate-reducing bacteria, the results revealed an interesting phenomenon of enriched coexistence but a reduced hydrogen sulfide generation with DIET application. In a stoichiometric relationship, around 26.6% of the total electrons were migrated from hydrogen sulfide production back to methane generation. Sensitivity analysis of life cycle assessment (LCA) was applied to better understand the environmental significance of electron diversion by biochar application in the systematic context of bioenergy recovery and biogas desulfurization. The LCA results characterized the benefits and limitations of DIET-driven desulfurization for the environmental performance of each impact category, while the potential improvement through better resource circularity in the desulfurization unit was also highlighted. Overall, built on experimental validation, this study frames relevant evaluations to achieve insights into the pivotal roles of biochar application as well as the quantitative interdependencies between DIET-driven desulfurization and AD sustainability.

36 citations

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TL;DR: In this article , the status of machine learning (ML) applications in four critical biorefinery systems (i.e., composting, fermentation, anaerobic digestion, and thermochemical conversions) as well as their advancements against traditional modeling techniques of mechanistic approach are scrutinized.

16 citations

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TL;DR: In this paper , the combination of biochar and bioaugmentation was evaluated by growing Methanosarcina thermophila on biochar support particles prior to augmentation of thermophilic food waste anaerobic digestion.

15 citations


Cited by
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TL;DR: This review is presented to provide an overview of the opportunities combining both hydrothermal and biological techniques for biomass valorization, and to assess the energy balance and economic feasibility of different integrated options reported in previous studies.
Abstract: Biomass valorization for the production of various value-added biochemicals and biofuels plays a significant role in modern biorefineries/bioenergy towards a climate neutrality future. Among the developed valorization techniques for biorefining, hydrothermal and biological treatments have been demonstrated to valorize raw biomass materials or upgrade biorefinery intermediate products to afford respectably desired product yields. From the perspective of both green chemistry and circular bioeconomy, whether the inter-disciplinary approach could achieve complete biomass valorization with balanced energy and extra profits remains questionable. This review is presented to provide an overview of the opportunities combining both hydrothermal and biological techniques for biomass valorization. Combinations including (1) hydrothermal pretreatment followed by biological valorization (such as enzymatic hydrolysis, fermentation, anaerobic digestion, or composting) and (2) hydrothermal valorization of substrates generated from biological techniques (such as enzymatic hydrolysis pretreated food waste, or anaerobic digestion produced digestate) for the production of biochar, biocrude or syngas are comprehensively reviewed. The recent advances regarding treatment conditions, synergies between hydrothermal and biological techniques, and optimal performances are summarized and compared. Assessment of the energy balance and economic feasibility of different integrated options reported in previous studies is also compared. Finally, challenges and perspectives for advancing integrated hydrothermal and biological techniques toward complete biomass valorization are concluded.

98 citations

Journal ArticleDOI
TL;DR: Reduced nitrogen loss and high quality compost could be produced from food waste digestate by adapting mitigation strategies, and the nitrogen dynamics cycle considering high ammonium nitrogen content in the digestate is evaluated.

84 citations

Journal ArticleDOI
TL;DR: Artificial Intelligence based Hybridized Intelligent Framework (AIHIF) has been proposed for automated recycling to optimizing the waste management process and results show that the proposed method enhances performance and accuracy when compared to other existing methods.

65 citations

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TL;DR: In this paper, the potential applications and challenges for hydrothermal carbonization (HTC) as green and sustainable way were presented, which will provide prospect for hydrochar as clean and renewable biofuel.

64 citations

Journal ArticleDOI
TL;DR: In this article , a review of municipal solid waste (MSW) to energy technologies taking the circular economy perspective is presented, and the critical characteristics of technologies for the MSW to energy routes are scrutinised.

62 citations