Showing papers by "Dongsheng Shen published in 2021"
TL;DR: In this paper, the authors examined the environmental impacts and energy consumption of three solid digestate treatment scenarios to quantify their impacts on the entire food waste-based biogas system: (1) incineration; (2) composting, and; (3) landfill.
34 citations
TL;DR: HMF evidently played the most important role in hydrochar formation, and was consumed approximately seven times more rapidly than either fructose or LA, and the hydro char formation mechanism reported herein may be applicable to other similar hydrothermal processes.
22 citations
TL;DR: In this paper, a batch of acid-tolerant inoculation sludge was domesticated as inoculum, and different concentrations of nano-magnetite were added to the propionic acid (PA) anaerobic digestion system to explore its effect on the PA degradation.
22 citations
TL;DR: Modulation of QS in denitrifying bacteria, possibly through quorum quenching or QS inhibition, could help to improve the reduction of nitrate in wastewater treatment.
Abstract: The bacterium Pseudomonas aeruginosa negatively regulates denitrification under anerobic conditions by two acyl-homoserine lactone quorum-sensing (QS) systems called las and rhl. However, it is unknown whether these systems have the same effect on denitrification in aerobic conditions. In this study, we investigated the regulation of las and rhl systems on aerobic denitrification. We showed that the removal of nitrate in P. aeruginosa PAO1 was repressed by both the las and rhl systems. The las and rhl systems had negative effects on activities of denitrifying enzymes NAP, NIR, NOR, and NOS. At the level of transcription, both QS systems inhibited the expression of target genes napA, nirS, norB, norC, and nosZ. Furthermore, the addition of an acylase, which degrades the acyl-homoserine lactone signals (AHLs), to wild type resulted in an increase in the removal of nitrate. Additionally, in aerobic denitrification process, the transcription factor DNR, which controls denitrification, was repressed by both QS systems. The results implied that modulation of QS in denitrifying bacteria, possibly through quorum quenching or QS inhibition, could help to improve the reduction of nitrate in wastewater treatment.
18 citations
TL;DR: Surprisingly, membrane fouling of electrically-assisted AnMBR (AnEMBR) at -0.5 V was increased, which was attributed to a dense biofilm-like structure formation, contrary to the conventional cognition that negative potential could mitigate the membrane fouled.
15 citations
TL;DR: In this article, a two-stage treatment method combining mechanical ball milling and microwave hydrothermal treatment (MHT) was investigated to improve the 5-hydroxymethylfurfural (HMF) yield.
15 citations
TL;DR: In this paper, the authors examined the economic benefits of food waste treatment projects in China and factors affecting them, including regional location, service population size, processing technique, and urban income.
Abstract: This study examines the economic benefits of food waste treatment projects in China and factors affecting them. National-level pilot projects for food waste treatment located in 29 cities were selected as samples. The economics of food waste recycling from the investors’ perspective, in terms of investment during the construction phase and cost and benefit during the operation phase, was assessed. Results indicate that the average tonnage investment of food waste treatment projects was RMB 700.0±188.9 thousand yuan, with a profit to cost ratio of 0.08±0.37. This ratio increased to 0.95±0.57 following the application of government subsidies. It highlights the limited economic benefits of food waste treatment facilities, which rely on government subsidies to maintain their operations in China. Further analysis using a multi-factor analysis model revealed that regional location, service population size, processing technique, and urban income exerted varying impacts on the economy of food waste treatment. Population size exerted the highest impact (P = 0.016) during the construction stage, and processing techniques notably influenced the project economy during the operation stage. The study highlights the need to prioritize service population size and processing techniques during economic decision-making and management of food waste recycling projects. The results of this study can serve as a valuable practical reference for guiding future policies regarding food waste treatment and related planning.
14 citations
TL;DR: Results showed that temperature, reaction time, and pH were significant interacting factors with respect to hydrolysis and melanoidins formation while the C/N ratio and moisture content of food waste had little impact.
Abstract: The occurrence of the Maillard reaction and melanoidins formation during the hydrothermal treatment of food waste can reduce the yield of volatile fatty acids (VFA); however, few studies have investigated the adverse effects of the Maillard reaction. This study identified the impact of hydrothermal treatment parameters on hydrolysis and melanoidins formation and optimized the hydrothermal treatment conditions to enhance VFA production by minimizing the impact of the Maillard reaction. A response surface methodology was employed to optimize the hydrothermal treatment parameters and VFA production was evaluated. Results showed that temperature, reaction time, and pH were significant interacting factors with respect to hydrolysis and melanoidins formation while the C/N ratio and moisture content of food waste had little impact. The optimal conditions for hydrothermal treatment (temperature of 132 °C, reaction time of 27 min, and a pH of 5.6) enhanced VFA production by 22.1%. Under optimal hydrothermal treatment conditions, a higher initial C/N ratio further increased VFA production.
14 citations
TL;DR: In this paper, microwave hydrothermal treatment (MHT) was used to produce HMF from food waste (FW) by optimizing the holding temperature (230°C) and the holding time (15min).
11 citations
TL;DR: The results show that the fluidization performance of the filling is the best under the one-side aeration mode with 30% filling ratio and the aeration intensity of MBBR was optimized by CFD model from the point of view of fluid mechanics.
9 citations
TL;DR: In this article, the authors compared and selected the computational fluid dynamics turbulence model to study the influence of aeration parameters on membrane fouling control and showed that the DES turbulence model had a higher precision and accuracy in predicting the average shear forces and the instantaneous shear force distribution on the membrane surface than the k-e turbulence model.
TL;DR: In this article, the As(III) was rapidly oxidized to As(V) via microbial activity, and substantial As was fixed in the solid phase, and the abundance of arsenite oxidase genes (aioA) was about four times higher in the moderate As (III) stressed treatment than in the untreated control.
TL;DR: In this paper, seventeen typical ARG subtypes were quantitatively investigated in refuse samples from small and medium-sized landfills with ages of  0.05 in abundance for other ARGs, including tetQ, tetW, ampC, blaCTX-M, BLaSHV, emrA, mefA, qNRD, qnrS, and mexF.
TL;DR: In this article, the effect of Fe2O3 on the leaching behavior of Cr in hazardous waste incineration fly ash (HWFA) after thermal treatment was investigated.
Abstract: The effect of Fe2O3 on the leaching behavior of Cr in hazardous waste incineration fly ash (HWFA) after thermal treatment was investigated. Addition of Fe2O3 could inhibit the static leaching behavior of Cr at most temperature conditions: the maximum reduction in leaching was 98.3% at 1200 °C. Long-term dynamic leaching behavior of Cr could be inhibited when using a thermal treatment temperature of 1200 °C and proportion of Fe2O3 exceeding 14.3%. At 1200 °C, Fe2O3 reacted strongly with the hazardous fraction of Cr in HWFA to form a stable chromite (Fe + 2 Cr2O4). The study results illustrate that the leaching behavior of Cr in HWFA after thermal treatment is affected by addition of Fe2O3 and treatment temperature. Adding Fe2O3 could effectively control the static and dynamic leaching behavior of Cr in HWFA after thermal treatment at 1200 °C, but excessive Fe2O3 addition accelerated dynamic leaching rate of Cr in HWFA after thermal treatment at 1100 °C.
TL;DR: It is found that water and air had a strong influence on the release of Cl−, and lower COD/Cl and -N/Cl ratios in ASL and RASL after day 175 indicated that lower Cl− pollution risk than that in AL and RAL.
Abstract: Landfill leachate has a high chloride (Cl−) content. Because it is highly mobile, and cannot be sorbed or transformed bio-chemically, it is important to have detailed information about how it migra...
TL;DR: In this paper, the influence of the root exudates of hyperaccumulator Sedum alfredii on Pseudomonas aeruginosa based on QS was explored.
TL;DR: In this paper, the conversion of zinc into a sulfide-containing plating sludge via a microwave hydrothermal sulfidation (MHS) process for use in heavy metal remediation by flotation is described.
Abstract: The present study describes the conversion of zinc into a sulfide-containing plating sludge via a microwave hydrothermal sulfidation (MHS) process for use in heavy metal remediation by flotation. T...