Mi Yan,Hongcai Su,Zhihao Zhou,Dwi Hantoko,Jianyong Liu,Jingyi Wang,Runpei Wang,Ekkachai Kanchanatip
The effluent of food waste (FWE) is generated during food waste treatment process. It contains high organic matter content and is difficult to be efficiently treated. In this study, the sample was collected from a 200 t/d food waste treatment center in Hangzhou, China. Subcritical and supercritical water gasification were employed to decompose and convert FWE into energy. The effects of reaction temperature (300–500 °C), residence time (20–70 min) and activated carbon loading (0.5–3.5 wt%) on syngas production and the remaining pollutants in liquid residue were investigated. It was found that higher reaction temperature and longer residence time favored gasification and pollutant decomposition, resulting in higher H 2 production and gasification efficiencies. It is noteworthy that the NH 3 -N was difficult to be converted and removed under current experimental conditions. The addition of activated carbon was found to increase the gasification efficiency. The highest total gas yield, H 2 yield, carbon conversion efficiency, gasification efficiency, total organic carbon removal efficiency and chemical oxygen demand removal efficiency were obtained from gasification at 500 °C for 70 min with 3.5 wt% activated carbon.
Mi Yan,Chuanhai Luo,Dicka Ar Rahim,Yu Liu,Haocheng Wang,Jinghao Ye,Yansong Sun,Ekkachai Kanchanatip
Hydrothermal carbonization has become increasingly prevalent in the pretreatment of food waste, leading to the generation of substantial volumes of liquid effluent. This hydrothermal liquid effluent from food waste (HLF) contains high content of organic compounds, making it challenging to treat using conventional methods. In this regard, the HLF was considered a potential source for energy production via supercritical water gasification (SCWG). This study aimed to develop effective bimetallic catalysts based on Ni/Al 2 O 3 with four different promoters (Cu, Co, La, and Ce), and investigated their performance in the catalytic SCWG for the treatment of HLF and hydrogen production. Among the tested promoters, the Ce-Ni catalyst was considered the most suitable in terms of its highest H 2 yield and H 2 selectivity. The optimal Ce content was found to be 5 wt%, with a catalyst dosage of 5 % by weight of HLF. These conditions resulted in the highest H 2 selectivity of 1.61 and a relatively high H 2 yield of 749.60 mmol/L under SCWG operating conditions of 480 °C and 30 min. Excessive catalyst dosages increased total syngas yield but reduced H 2 selectivity. The stability test demonstrated that the Ce promoter contributed to enhancing the catalyst resistance to deactivation by coke deposition. The hydrogen production of 5Ce-Ni decreased by 13.8 % after three reuses, whereas a larger decrease of 26.0 % was observed with Ni/Al 2 O 3 . These findings indicate that Ce-Ni catalyst show promise for enhancing H 2 -rich syngas production in the SCWG of hydrothermal liquid effluent from food waste.
Wang Qing,Jin Wenbiao,Han Wei,Song Kang,Chen Yidi,Chen Chuan,Jiang Guangming,Zhou Xu
In order to achieve strain improvement and reduction of fermentation medium cost, atmospheric and room temperature plasma (ARTP) mutagenesis and microbial microdroplet culture (MMC) high-throughput screening were used to obtain high-yield Aurantiochytrium sp. strain. Meanwhile, low-cost food waste liquid was added into culture medium to reduce cost. The results showed that the optimal treatment time of ARTP mutagenesis for Aurantiochytrium sp. was 25 s, and 20 mutant strains were screened out by MMC to investigate their performance. The most significant increase in DHA yield was mutant Aurantiochytrium sp. MA20, whose biomass, lipid, and DHA yield were 29.0 ± 0.24, 15.8 ± 0.11, and 9.22 ± 0.37 g/L and 5.77, 16.9, and 83.2% higher than those of original strain, respectively. Compared with the original strain, the DHA proportion in total fatty acids of Aurantiochytrium sp. MA20 increased from 37.2 to 58.3%, while the DHA proportion in biomass increased from 18.4 to 31.7%. The genetic stability for Aurantiochytrium sp. MA20 showed that the yield of biomass, lipid, and DHA of the 50th generation were 29.1 ± 0.13, 16.2 ± 0.31, and 9.47 ± 0.26 g/L, respectively, which was no significant difference between original strain, indicating that the mutant MA20 could be inherited stably. Using food waste liquid to replace 100% yeast extract and 50% sea water of the fermentation medium, the DHA yield reached 9.54 g/L, which was equivalent to that of traditional medium, while the cost of medium was reduced by 45% that achieved the recycle of food waste resource. Graphical abstract
危险品化学品经营许可证（带存储）