Article
Agricultural Engineering
Jibao Liu, Xianglin He, Hui Zhong, Pei Lei, Junya Zhang, Yufeng Xu, Yuansong Wei
Summary: Thermal hydrolysis reduces the content of methylmercury in sewage sludge, with high temperature promoting both mercury methylation and methylmercury demethylation. Ruminococcaceae, Peptococcaceae, and Lachnospiraceae are potential methylators during hydrolysis and acidogenesis stage, while methylmercury demethylation dominates in the late period of anaerobic digestion.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
Jibao Liu, Xianglin He, Yufeng Xu, Zhuang Zuo, Pei Lei, Junya Zhang, Yongguang Yin, Yuansong Wei
Summary: The fate of mercury and MeHg during full-scale anaerobic digestion was investigated, showing that demethylation of MeHg was dominant and likely due to physico-chemical impacts. Microbial methylation or demethylation seemed negligible in terms of MeHg transformation during the anaerobic digestion process.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
M. S. Romero-Guiza, J. Palatsi, X. Tomas, P. Icaran, F. Rogalla, V. M. Monsalvo
Summary: The study shows that alkaline pre-treatment of grease trap waste can improve the bioavailability of organic matter and facilitate its use as a co-substrate. Full-scale anaerobic co-digestion assays of pre-treated grease trap waste and sewage sludge did not show inhibitory or operational problems under experimental conditions. An economic assessment for a 160,000 population equivalent WWTP in a European scenario showed a relatively short payback period.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Engineering, Environmental
Qian Chen, Bing Zhao, Yuhui Zhang, Fenfen Zhu, Huan Wang, Jiawei Wang, Xingmin Fu
Summary: The environmental risk of heavy metals in sewage sludge from a full-scale Cambi (R) thermal hydrolysis + anaerobic digestion sludge treatment plant was discussed based on four seasons' data. Results showed that the heavy metal concentrations in the sludge increased significantly due to enrichment effect caused by organic degradation, except for Cd. The chemical fractions of different heavy metals varied greatly in the raw sludge, and their residual fractions slightly increased after treatment. Thermal hydrolysis and anaerobic digestion transformed some heavy metal fractions. Deep dehydration reduced the mass of heavy metals in the sludge (less than 10%). The potential ecological risk of heavy metals was low when sludge was applied to soil according to GB 4284-2018, and the accumulation amounts of heavy metals in test soil and rural soil did not exceed GB 36600-2018 and GB 15618-2018.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Review
Energy & Fuels
Sylwia Myszograj, Ewelina Pluciennik-Koropczuk
Summary: Operating and research experiments have shown that thermal treatment of sewage sludge before methane fermentation can lead to several benefits, including increased biodegradability of substrates, improved dewaterability and hygienization of fermentate, reduced odour emission, higher biogas production, and improved energy balance. Various methods such as mechanical homogenization, microwaves, ultrasonic waves, chemical agents, thermal methods, and biological processes can be used for disintegration (liquefaction). This article reviews the literature on thermal hydrolysis research and highlights its positive effects on hydrolysis, biogas potential, and sludge degradation during anaerobic digestion.
Article
Engineering, Environmental
Fang Zhang, Ding-Kang Qian, Zi-Qian Geng, Kun Dai, Wei Zhang, Mark C. M. van Loosdrecht, Raymond Jianxiong Zeng
Summary: The hydrolysis of alginate, a main component of extracellular polymeric substances (EPS) in waste-activated sludge, is crucial for enhancing methane production. The alginate-degrading consortia (ADC) showed a significant increase in methane production and biological methane potential, indicating the importance of alginate in EPS for methane recovery. Future research should focus on investigating the microbial changes in ADC for stable digestion of waste-activated sludge.
ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS
(2021)
Article
Environmental Sciences
Kai Feng, Luxin Yang, Liang Chen, Qi Jing, Huan Li, Debin Li, Jiayi Liu, Jiabai Cai, Zhou Deng
Summary: This paper proposes a method of anaerobic co-digestion of food waste and sludge to enhance their methane potential. The methane yield of this co-digestion is higher compared to the co-digestion of sludge with food waste. The addition of thermally hydrolyzed sludge weakens the synergistic effect, while the addition of THS filtrate enhances it.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Thermodynamics
Justyna Walczak, Beata Karolinczak, Monika Zubrowska-Sudol
Summary: This study investigated the applicability of co-digestion and hydrodynamic disintegration in methane production from sewage sludge and organic waste, taking into account carbon footprint assessment. The results showed that co-digestion at a specific mixing ratio resulted in the highest increase in methane production, while hydrodynamic disintegration was only effective at a lower energy density. The carbon footprint of monodigestion and co-digestion were comparable, with the highest carbon footprint observed in monodigestion of disintegrated sewage sludge.
Article
Energy & Fuels
Jakub Mukawa, Tadeusz Pajak, Tadeusz Rzepecki, Marian Banas
Summary: This paper presents the energy potential of biogas obtained from the anaerobic digestion of sewage sludge preceded by thermal hydrolysis. The study shows that this technology can efficiently process sludge and generate a significant amount of biogas. This research is important for meeting energy demand.
Article
Environmental Sciences
Xiuqin Cao, Haoyun Yuan, Yuqing Tian
Summary: Anaerobic co-digestion of sewage sludge with thermal hydrolysis pretreatment and food waste improved stability, methane production, and dewaterability of the reactor. The microbial community analysis showed enhanced bacterial diversity and richness, with acetoclastic methanogens becoming the dominant methanogenic microorganisms.
ENVIRONMENTAL TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yanfei Tang, Jing Sun, Bin Dong, Xiaohu Dai
Summary: This study attempted to alleviate the inhibitory effect of humic acids (HA) in sludge anaerobic digestion (AD) by directly treating sludge in the digestor with citric acid (CA). Results showed that CA treatment at appropriate dosages could effectively enhance methane production and promote sludge solubilization and hydrolysis. The study suggests that more attention should be given to HA produced and accumulated in AD rather than raw sludge to alleviate the inhibitory effect.
Review
Environmental Sciences
Perrine Devos, Mathieu Haddad, Helene Carrere
Summary: The research examines the optimal temperature for Thermal Hydrolysis Process (THP) applied to municipal sludge, suggesting a temperature range of 140-160 degrees Celsius to minimize the production of refractory compounds and maximize anaerobic digestion and dewatering performance.
WASTE AND BIOMASS VALORIZATION
(2021)
Article
Environmental Sciences
Chunsheng Qiu, Jiakang Li, Chenchen Wang, Nannan Liu, Li Qi, Dong Wang, Shaopo Wang, Liping Sun
Summary: The aim of this study was to investigate the migration and speciation transformation of heavy metals (HMs) in sewage sludge during the combined process of thermal hydrolysis, anaerobic digestion and heat-drying. The majority of HMs remained in the solid phase after treatment. Thermal hydrolysis led to a slight increase in the concentrations of Cr, Cu and Cd. Anaerobic digestion resulted in a significant concentration of all measured HMs. Heat-drying, on the other hand, caused a slight decrease in the concentrations of all HMs. The stability of HMs in the sludge samples was enhanced after treatment, reducing environmental risks in the final dried sludge samples.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Thermodynamics
D. Fernandez-Polanco, E. Aagesen, M. Fdz-Polanco, S. I. Perez-Elvira
Summary: Anaerobic digestion is commonly used for sludge treatment in WWTPs, with thermal hydrolysis being favored for its economic advantages. The decision to adopt TH technology varies based on local regulations and pricing, with different objectives leading to different optimal configurations. Pre-, inter- and post-treatments of TH process offer distinct advantages and drawbacks, with site-specific conditions being key in determining the best location within the WWTP.
Review
Environmental Sciences
Phuong Linh Ngo, Isuru A. Udugama, Krist Gernaey, Brent R. Young, Saeid Baroutian
Summary: Sewage sludge management is a topic of interest due to the challenges of overpopulation and its potential as a bioenergy source. Thermal hydrolysis is a promising technology for sludge pre-treatment, but faces challenges such as dark color affecting UV disinfection and the formation of inhibitors impacting methane production. Advanced thermal hydrolysis, an oxidative process, has been introduced to overcome these challenges.
Article
Agronomy
Francesc X. Prenafeta-Boldu, Belen Fernandez, Marc Vinas, Joan Noguerol, Joan Soler, Josep Illa
Summary: Solar drying of pig slurries was tested in a pilot-scale greenhouse under Mediterranean conditions, utilizing acidification and biofiltration to prevent gaseous emissions and controlling ventilation regime for drying. The water content of pig slurries stabilized around 10%, meeting regulations for solid organic fertilizers, with further discussions on operational costs and fertilizing quality parameters.
Review
Energy & Fuels
Raquel Iglesias, Raul Munoz, Maria Polanco, Israel Diaz, Ana Susmozas, Antonio D. Moreno, Maria Guirado, Nely Carreras, Mercedes Ballesteros
Summary: This paper reviews the role of biogas as advanced biofuel in the renewable energy system, highlighting the main raw materials and technologies used for biogas production and upgrading. Biomethane could be competitive in the transport and power generation sectors, but production issues need to be addressed.
Article
Engineering, Environmental
C. Gonzalez, B. Fernandez, F. Molina, M. A. Camargo-Valero, C. Pelaez
Summary: Struvite from nutrient-rich wastewaters has been identified as a potential substitute for commercial mineral fertilisers, reducing threats to global food security and prolonging phosphate rock reserves. It increases the uptake of N and P in grass, with lower heavy metal concentration compared to Biosolids and compliance with Colombia and European fertiliser regulations. The efficacy as a slow-release fertiliser is dependent on crystal particle size, with potential for nutrient recovery and reuse in agriculture.
WATER SCIENCE AND TECHNOLOGY
(2021)
Article
Energy & Fuels
D. G. Rosero, N. L. Diaz, C. L. Trujillo
Summary: The way to organize the generation, storage, and management of renewable energy and energy consumption features has become increasingly important in recent years. This article discusses tasks associated with a microgrid cluster under a machine learning perspective, focusing on elements considered to define a cloud-based architecture for real-time energy management using machine learning techniques.
Article
Agriculture, Dairy & Animal Science
M. Devant, A. Perez, C. Medinya, J. Riera, J. Grau, B. Fernandez, F. X. Prenafeta-Boldu
Summary: This study evaluated the effects of dietary crude protein concentration on animal performance, nitrogen excretion, and manure nitrogen volatilization. The results showed that decreasing dietary protein content can reduce nitrogen excretion and manure nitrogen losses without impairing animal performance.
Article
Environmental Sciences
Lorenzo Rambaldo, Hector Avila, Monica Escola Casas, Miriam Guivernau, Marc Vinas, Rosa Trobajo, Javier Perez-Burillo, David G. Mann, Belen Fernandez, Carme Biel, Luigi Rizzo, Josep M. Bayona, Victor Matamoros
Summary: Groundwater pollution has increased due to intensified agricultural and livestock activities, leading to a reduction in freshwater resources. This study investigated a green technology using a photobioreactor and cork filter to remove pollutants from groundwater. The results showed that the technology was moderately effective in removing nitrates, antibiotics, and pesticides, but its efficiency decreased with shorter hydraulic retention time, with pesticides being the most affected compounds.
Meeting Abstract
Agriculture, Dairy & Animal Science
Lourdes Llonch, Sonia Marti, Belen Fernandez, Francesc X. Prenafeta-Boldu, Marcal Verdu, Xavier Salsa, Maria Devant
JOURNAL OF ANIMAL SCIENCE
(2022)
Article
Agricultural Engineering
A. Otero, C. Segura, L. Tey, G. Masferrer, J. Comaposada, B. Fernandez
Summary: This study evaluates the feasibility of using a handheld near infrared spectrometer to predict moisture, fat, and protein content in animal by-products (ABP) mixtures for biogas production. The spectrometer was calibrated using partial least square regression and tested with independent data. The results showed good determination coefficient values and low root mean square errors. The handheld NIR spectrometer was compared to a benchtop NIR spectrometer and found to be a useful tool for rapid characterization of feedstocks in biogas plants.
BIOMASS & BIOENERGY
(2023)
Article
Environmental Sciences
Monica Escola Casas, Miriam Guivernau, Marc Vinas, Belen Fernandez, Rafaela Caceres, Carme Biel, Victor Matamoros
Summary: About 13% of monitored groundwater stations in Europe exceed the permitted levels of nitrates, while about 7% exceed the permitted levels of pesticides. This study evaluated the performance of using wood pellets and granulated cork as carbon sources in biofilters for removing nitrates and pesticides. The water-saturated wood biofilter achieved the best nitrate removal, while the cork biofilters lost their denitrification power over time. All biofilters showed high removal rates for certain pesticides.
Article
Energy & Fuels
D. G. Rosero, E. Sanabria, N. L. Diaz, C. L. Trujillo, A. Luna, F. Andrade
Summary: This paper evaluates the integration of tools such as the internet of things, cloud computing, and machine learning into a microgrid real-time energy management system. The proposed cloud-based system is tested by solving an economic power dispatch problem in a multi-microgrid environment. As demonstrated by the experimental evidence, combining machine learning techniques and internet of things tools with a scalable and autonomous real-life cloud-based energy management system architecture improves functionality, enhances energy forecasting, and reduces costs.
Article
Environmental Sciences
L. Morey, B. Fernandez, L. Tey, C. Biel, A. Robles-Aguilar, E. Meers, J. Soler, R. Porta, M. Cots, V. Riau
Summary: The increasing energy and fertilizer consumption in agriculture necessitate the development of sustainable alternatives. This study investigated the use of solar drying technology combined with acidification to reduce the water content and gaseous emissions of manure-derived digestate and solid fraction of digestate. The acidified products showed higher nitrogen and ammonia nitrogen recovery, as well as significant reductions in ammonia and methane emissions. However, N2O emissions increased. The dried products met EU regulations for organic fertilizers, but zinc concentrations exceeded legal limits in some cases.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Computer Science, Information Systems
Luis Fernando Rico-Riveros, Cesar Leonardo Trujillo-Rodriguez, Nelson Leonardo Diaz-Aldana, Catalina Rus-Casas
Summary: To ensure society's survival, a significant amount of energy is needed for economic and social development. Agricultural biomass, as an alternative energy source, has the potential to produce electrical and thermal energy in rural areas, reducing reliance on fossil fuels.
Article
Agriculture, Dairy & Animal Science
Lluis Morey, Alex Bach, Daniel Sabria, Victor Riau, Belen Fernandez, Marta Terre
Summary: Two feeding trials were conducted on dairy cows to evaluate the effects of a precision feeding strategy on nutrient adjustment and N emissions. The results showed that precision feeding can reduce N excretion without affecting milk production performance, but it increases methane and carbon dioxide emissions from manure.
ANIMAL FEED SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Nelson L. Diaz, Francesc Guinjoan, Guillermo Velasco-Quesada, Adriana C. Luna, Josep M. Guerrero
Summary: This paper proposes a cooperative strategy for the flexible integration of stand-alone AC microgrids using an intermediate multiterminal DC link based on voltage source converters. The strategy manages cooperative power exchange between microgrids through a knowledge-based fuzzy inference system that relies on the current operating conditions of the microgrids. The effectiveness and expandability of the proposed cooperative energy exchange strategy for enhancing the overall operation of multiple integrated microgrids have been fully verified by simulation and experimental validation.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2023)
Article
Energy & Fuels
Calloquispe Huallpa Ricardo, Luna Hernandez Adriana, Diaz Aldana Nelson
Summary: This paper presents two methodologies for equalization and energy management in a microgrid. The first method prioritizes equalization, achieving it quickly at the expense of grid usage, while the second method focuses on energy management and achieves slower equalization, reducing overall costs. A genetic algorithm is used to optimize the current delivery of each battery in the microgrid. Two case studies in MATLAB and Simulink demonstrate the effectiveness of the proposed optimizations, showing that both methods achieve energy management and equalization without compromising the optimal operation of the microgrid. The first method achieves equalization in 29 seconds with a consumption of 47 kW*s from the grid, while the second method achieves equalization in 110 seconds with no energy consumption from the grid.
JOURNAL OF ENERGY STORAGE
(2023)
