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Journal of Environmental Sciences 2021年第10期33卷 145-151页

作者： Jiajun Sun Junxue Song Wei Fang Hongbin Cao Beijing Engineering Research Center of Process Pollution Control Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China Xiong’an Group Ecological Construction Investment Co.Ltd. Baoding 071700China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Chemistry and Environmental Engineering China University of Mining and TechnologyBeijing 100083China

This study investigated a combined low-thermal and CaO_(2)pretreatment to enhance the volatile fatty acid(VFA)production from waste activated sludge(WAS).The fermentative product was added to a sequencing batch reactor(SBR)as an external carbon source to enhance nitrogen *** results showed that the combined pretreatment improved WAS solubilization,releasing more biodegradable substrates,such as proteins and polysaccharides,from TB-EPS to LB-EPS and *** maximum VFA production of 3529±188 mg COD/L was obtained in the combined pretreatment(0.2 g CaO_(2)/g VS+70℃for 60 min),which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test,***,when the fermentative liquid was added as an external denitrification carbon source,the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.

关键词： Waste activated sludge Anaerobic digestion Calcium peroxide Low-thermal pretreatment volatile fatty acids

A novel online analyzer for accurate and rapid measurement of volatile fatty acids in anaerobic wastewater treatment

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Journal of Environmental Sciences 2022年第12期34卷 72-82页

作者： Qingshan Lin Yanchao Yuan Feixiang Zan Hui Lu Zongping Wang Gang Guo School of Environmental Science and Engineering Huazhong University of Science and Technology(HUST)Key Laboratory of Water and Wastewater TreatmentMOHURDWuhan 430074China Department of Environmental Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

volatile fatty acids(VFAs), which are largely generated during the anaerobic acidification process, are considered to be reliable indicators of the stable process operation. However,the common methods for monitoring VFAs are offline, and they are typically manual requiring time-consuming, costly and complex instruments. This study aims to develop a novel online analyzer for automatic measuring VFAs, which was based on the 5-p H point titration, embedded with a proportional-integral-derivative(PID) feedback control system. The results show that it can achieve accurate and rapid monitoring of VFAs ranging between 0-400 mg/L(<9 min/sample) but simultaneously faces the problems of overtitration and interference of complex characteristics of wastewater. In order to improve its accuracy and stability, the effects of three general coefficients(K_(I),K_(P), and K_(D)) of PID on the titration were investigated, and the optimal values of K_(I), K_(P), and K_(D)were found to be 1.5, 1.0, and-1.0~0.5,respectively. Besides, the initial titration speed was set at 0.06 m L/min, equal to the minimum speed of the peristaltic pump, and the dichotomy approach was integrated into the PID feedback controller. Owing to the above improvements, the relative mean deviation and standard deviation of measuring VFAs in both synthetic and real wastewaters were mostly lower than 5.0% and 5.0 mg/L, proving the online analyzer is rapid, accurate and reliable.

关键词： volatile fatty acids Online analyzer 5-pH point titration PID feedback control Anaerobic process

Effects of sludge age on anaerobic acidification of waste activated sludge: volatile fatty acids production and phosphorus release

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Journal of Environmental Sciences 2021年第7期33卷 11-21页

作者： Sisi Chen Xiaohu Dai Dianhai Yang Bin Dong State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China

Effects of sludge age on volatile fatty acids (VFAs) production and Phosphorus (P) release during anaerobic acidification of waste activated sludge (WAS) were *** batch reactors (SBR) fed with simulating domestic sewage were applied to produce WAS of different sludge ages,and batch tests were used for anaerobic *** maximum dissolved total organic carbon,release of PO_(4)^(3+)-P,and accumulation of acetate (C2),propionate (C3),butyrate (C4),and valerate (C5) decreased by 56.2%,55.8%,52.6%,43.7%,82.4%and 84.8%,respectively,as the sludge age of WAS increased from 5 to 40 *** degradation of protein played a dominating role in decreasing DTOC and VFAs ***,the increase in molecular weight of organics and organic nitrogen content in the supernatant after acidification suggested that the refractory protein in WAS increased as sludge age *** the production of C2,C3,C4,and C5 from WAS decreased as the sludge age increased,the proportions of C2 and C3 in VFAs increased,which might be due to the declined production of C5 from protein and the faded genus *** sludge age of WAS at a relatively low level (<10 days) is more appropriate for anaerobic acidification of WAS as internal carbon sources and P resource.

关键词： Sludge age Waste activated sludge Acidification volatile fatty acids Microbial community

Dietary pectic oligosaccharide supplementation improves rat reproductive performance via regulating intestinal volatile fatty acids during middle gestation

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Animal Nutrition 2020年第2期6卷 210-216页

作者： Minghui Liu Xiangbing Mao Daiwen Chen Bing Yu Jun He Ping Zheng Jie Yu Junqiu Luo Yuheng Luo Jianping Wang Quyuan Wang Huifen Wang Animal Nutrition Institute Sichuan Agricultural UniversityChengdu611130China Key Laboratory of Animal Disease-Resistance Nutrition Chinese Ministry of EducationChengdu611130China Key Laboratory of Animal Disease-resistant Nutrition and Feed Chinese Ministry of Agriculture and Rural AffairsChengdu611130China Key Laboratory of Animal Disease-resistant Nutrition SichuanChengdu611130China

As a kind of green additive,pectic oligosaccharide(POS) may regulate some physiological functions of animals,such as gut health,antioxidant capacity,immunity and lipid *** study aimed to identify whether POS administration can improve maternal reproduction,and to determine the possible metabolism.A total of 48 pregnant Wistar rats randomly allotted into 2 groups,and each group was fed a diet supplemented with 0 or 800 mg/kg of *** oligosaccharide administration increased rat born number(P volatile fatty acid concentrations of cecal digesta(P volatile fatty acid concentrations in rat gut improving hormone and inflammatory-cytokine productions,and antioxidant capacity.

关键词： Pectic oligosaccharide Rat reproductive performance volatile fatty acids Hormone and cytokine generations Antioxidant capacity

Valorisation of industrial hemp (Cannabis sativa L.) residues and cheese whey into volatile fatty acids for single cell protein production

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Environmental Science and Ecotechnology 2024年第5期21卷 369-380页

作者： Carlo Moscariello Silvio Matassa Francesco Pirozzi Giovanni Esposito Stefano Papirio Department of Civil Architectural and Environmental EngineeringUniversity of Napoli Federico IIvia Claudio 2180125NapoliItaly

The production of single cell protein(SCP)using lignocellulosic materials stands out as a promising route in the circular bioeconomy ***,multiple steps are necessary for lignocellulosics-to-SCP processes,involving chemical pretreatments and specific aerobic *** there are no studies that investigated the SCP production from lignocellulosics by using only biological processes and microbial biomass able to work both anaerobically and *** this view,the valorisation of industrial hemp(Cannabis sativa L.)biomass residues(HBRs),specifically hurds and a mix of leaves and inflorescences,combined with cheese whey(CW)was investigated through a semi-continuous acidogenic co-fermentation process(co-AF).The aim of this study was to maximise HBRs conversion into VFAs to be further used as carbon-rich substrates for SCP *** process conditions were tested by either removing CW or increasing the amount of HBRs in terms of VS(i.e.,two and four times)to evaluate the performance of the co-AF *** HBRs resulted in a proportional increase in VFA production up to 3115 mg HAc L^(-1),with experimental production nearly 40%higher than theoretical *** synergy between HBRs and CW was demonstrated,proving the latter as essential to improve the biodegradability of the *** produced VFAs were subsequently tested as substrates for SCP synthesis in batch aerobic tests.A biomass concentration of 2.43 g TSS L^(-1) was achieved with a C/N ratio of 5.0 and a pH of 9.0 after two days of aerobic fermentation,reaching a protein content of 42%(g protein per g TSS).These results demonstrate the overall feasibility of the VFA-mediated HBR-to-SCP valorisation process.

关键词： Hemp biomass residues Cheese whey volatile fatty acids Acidogenic fermentation Single cell protein

A combined pig model to determine the net absorption of volatile fatty acids in the large intestine under different levels of crude fiber

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Animal Models and Experimental Medicine 2023年第4期6卷 375-380页

作者： Shengjun Zhao Liangkang Lv Taotao Wu Zhi Feng Qiang Li Long Lei Zhengya Liu Hui Zhang Ying Ren Hubei Key Laboratory of Animal Nutrition and Feed Science Wuhan Polytechnic UniversityWuhanChina State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina

Background:This study aimed to develop a combined model to quantify the net absorption of volatile fatty acids(VFA)in the large intestine(LI)of ***:Fifteen female growing pigs(Duroc×Large White×Landrace)were ranked by body weight(30±2.1 kg)on day 0 and assigned to one of three treatments,namely the basal diet containing different crude fiber(CF)levels(LCF:3.0%CF,MCF:4.5%CF,and HCF:6.0%CF).The pigs were implanted with the terminal ileum fistula and the cannulation of the ileal mesenteric vein(IMV),portal vein(PV),and left femoral artery(LFA)from days 6 to 7.[13 C]-Labeled VFA and P-aminohippuric acid were constantly perfused into the terminal ileum fistula and the cannulation of the IMV(day 15),*** samples were collected from the PV and the LFA during perfusion(5 h),and LI samples were ***:The net flux of[12 C]-acetic acid in the PV was greater for LCF versus MCF(p=0.045),but no difference was observed in the net flux of[12 C]-propionic acid(p=0.505)and[12 C]-butyric acid(p=0.35)in the PV among *** deposition of[12 C]-acetic acid in the LI was greater for LCF versus MCF(p=0.014),whereas the deposition of[12 C]-propionic acid(p=0.007)and[12 C]-butyric acid(p=0.037)in the LI was greater for LCF versus ***:In conclusion,this pig model was found conducive to study the net absorption of VFAs in the LI,and LCF had more net absorption of VFAs in the LI than MCF and HCF.

关键词： crude fiber growing pigs large intestine T-type fistula volatile fatty acids

Enhancing corn stalk-based anaerobic digestion with different types of zero-valent iron added during the acidification stage:Performance and mechanism

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Journal of Environmental Sciences 2024年第11期145卷 64-74页

作者： Xiang Liu Yue Liu Min Wang Qianzhen Deng Hao Yang College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution Wenzhou UniversityWenzhou 325035China Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse Anhui Jianzhu UniversityHefei 230009China

Anaerobic digestion has been defined as a competitive approach to facilitate the recycling of corn ***,few studies have focused on the role of direct interspecies electron transfer(DIET)pathway in the acidification stage under the addition of different particle sizes of zero-valent iron(ZVI).In this study,three types of ZVI,namely iron filings,iron powder and nanoscale iron,were investigated,respectively,to enhance its high-value *** in volatile fatty acids(VFAs)and methane(CH4)production associated with the underlyingmechanisms were emphatically *** indicated that the addition of ZVI could increase the concentration of VFAs,with the most outstanding performance observed with the use of nanoscale ***,the conversion of propionic acid to acetic acid was driven by adding ZVI with no between-group differences in acidizing ***,the substrate was more fully utilized when supplied with iron powder compared with other groups in methanogenic phase,thereby displaying the maximumCH4 yield with a value of 263.1 mL/(g total solids(TS)).However,adding nanoscale iron could signally shorten the digestion time(T80),saving 7 days in comparison to the group of iron powder.

关键词： Zero-valent iron Corn stalk Anaerobic digestion volatile fatty acids Methane

Potassium ferrate pretreatment promotes short chain fatty acids yield and antibiotics reduction in acidogenic fermentation of sewage sludge

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Journal of Environmental Sciences 2022年第10期34卷 41-52页

作者： Zihao Qiao Suyun Xu Wanqiu Zhang Shuyin Shi Wei Zhang Hongbo Liu School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai 200093China Centillion Resource Recycling(Wuxi)Co.Ltd. Wuxi 214000China

During the acidogenic fermentation converting waste activated sludge (WAS) into shortchain fatty acids (SCFA), hydrolysis of complex organic polymers is a limiting step and the transformation of harmful substances (such as antibiotics) during acidogenic fermentation is unknown. In this study, potassium ferrate (KFeO) oxidation was used as a pretreatment strategy for WAS acidogenic fermentation to increase the hydrolysis of sludge and destruct the harmful antibiotics. Pretreatment with KFeOcan effectively increase the SCFA production during acidogenic fermentation and change the distribution of SCFA *** the dosage of 0.2 g/g TS, the maximum SCFA yield was 4823 mg COD/L, which is 28.3times that of the control group;acetic acid accounts for more than 90% of the total SCFA. The higher dosage (0.5 g/g TS) can further increase the proportion of acetic acid, but inhibit the overall performance of SCFA production. Apart from the promotion of hydrolysis and acidogenesis, KFeOpretreatment can also simultaneously oxidizes and degrades part of the antibiotics in the sludge. When the dosage is 0.5 g/g TS, the degradation efficacy of antibiotics is the most significant, and the contents of ofloxacin, azithromycin, and tetracycline in the sludge are reduced by 69%, 42%, and 50%, respectively. In addition, KFeOpretreatment can also promote the release of antibiotics from sludge flocs, which is conducive to the simultaneous degradation of antibiotics in the subsequent biological treatment process.

关键词： Acidogenic fermentation Antibiotics Potassium ferrate Oxidation pretreatment Sewage sludge volatile fatty acids

Machine learning enabled prediction and process optimization of VFA production from riboflavin-mediated sludge fermentation

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Frontiers of Environmental Science & Engineering 2023年第11期17卷 181-193页

作者： Weishuai Li Jingang Huang Zhuoer Shi Wei Han Ting Lü Yuanyuan Lin Jianfang Meng Xiaobing Xu Pingzhi Hou College of Materials and Environmental Engineering Hangzhou Dianzi UniversityHangzhou 310018China China-Austria Belt and Road Joint Laboratory on Artificial Intelligence and Advanced Manufacturing Hangzhou Dianzi UniversityHangzhou 310018China Zhejiang Province Environmental Engineering Co.Ltd. Hangzhou 310012China M-U-T Maschinen-Umwelttechnik-Transportanlagen GmbH Stockerau 2000Austria

Riboflavin is a redox mediator that promotes volatile fatty acids(VFAs)production from waste activated sludge(WAS)and is a promising method for WAS ***,time-and labor-consuming experiments challenge obtaining optimal operating conditions for maximal VFA *** this study,three machine learning(ML)models were developed to predict the VFAs production from riboflavin-mediated WAS fermentation *** the three tested ML algorithms,eXtreme Gradient Boosting(XGBoost)presented the best prediction performance and excellent generalization ability,with the highest testing coefficient of determination(R^(2)of 0.93)and lowest root mean square error(RMSE of 0.070).Feature importance analysis and their interactions using the Shepley Additive Explanations(SHAP)method indicated that pH and soluble protein were the top two input features for the *** intrinsic correlations between input features and microbial communities corroborated this *** the optimized ML model,genetic algorithm(GA)and particle swarm optimization(PSO)solved the optimal solution of VFA output,predicting the maximum VFA output as 650 mg COD/g *** study provided a data-driven approach to predict and optimize VFA production from riboflavin-mediated WAS fermentation.

关键词： Machine learning volatile fatty acids Riboflavin Waste activated sludge eXtreme Gradient Boosting

Transformation of organic matters in fresh leachate during anaerobic degradation under long hydraulic retention time

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Journal of Environmental Sciences 2009年第9期21卷 1302-1308页

作者： XU Suyun,HE Pinjing,LU Fan,LI Min,SHAO Liming State Key Laboratory of Pollution Control and Resources Reuse,Key Laboratory of Yangtze River Water Environment,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China [a]State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

This study investigated the biodegradability of fresh leachate from a young municipal solid waste landfill at the inoculum to substrate ratios （V/V） of 10/100, 25/100, 50/100 and 100/100, as well as the transformation of organic matters in leachate under prolonged hydraulic retention time （HRT） of 50 d. Fresh leachate showed a good biodegradability, with chemical oxygen demand （COD） removal efficiency as high as 87%-92% and cumulative methane yield close to theoretical value （0.35 L CH4/g CODdeg）. Methane production and COD depletion presented biphasic characteristics associated with the successive utilization of two major intermediates, acetate and propionate, The biphasic degradation of fresh leachate was resulted from the different hydrolysis rates of diverse substrates and the changes in microorganism community structure. After 50 d, the effluents were dominated by high-MW organic compounds （MW 〉 10 kDa） at each inoculum ratio, which might be refractory compounds released from cell lyses.

关键词： biodegradability biomass lyses methane production ratio of inoculum to substrate volatile fatty acids