Review
Biotechnology & Applied Microbiology
Santosh Kumar, Roy Posmanik, Sabrina Spatari, Victor C. Ujor
Summary: Due to climate change and drought, it is crucial to develop new technologies for water recovery from nutrient-rich effluents. Anaerobic digestate contains valuable minerals that can be used as nutrients for fermentation, enabling water recovery and bio-production of chemicals.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2022)
Article
Engineering, Environmental
F. Granzotto, C. Aita, D. D. Silveira, F. D. Mayer, S. B. Pujol, J. A. Pinas, R. Hoffmann
Summary: Anaerobic digestion proved to be an efficient method for treating organic wastes from university restaurants, achieving high removal rates of pollutants and producing biogas and digestate for potential use as organic fertilizer.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Review
Agricultural Engineering
Wei Wang, Jo-Shu Chang, Duu-Jong Lee
Summary: The flourishing of anaerobic digestion (AD) in waste treatment highlights the importance of valorization of digestate, which determines the benefits of the AD process. The perception of digestate has shifted from waste to products to realize the concept of circular economy and maximize its benefits. This review provides an overview of the current status of digestate valorization, focusing on thermal-chemical methods, and summarizes novel valorization methods from recent research, highlighting prospects for digestate valorization.
BIORESOURCE TECHNOLOGY
(2023)
Article
Agricultural Engineering
Konstantin Dinkler, Bowen Li, Jianbin Guo, Benedikt Huelsemann, Gero C. Becker, Joachim Mueller, Hans Oechsner
Summary: The study found that the majority of phosphate in biogas digestate is inorganic, and it is essential to analyze inorganic phosphate for optimal nutrient recovery. Phosphate concentration in extracts was found to be independent of extraction time, highlighting the importance of controlling parameters during different extraction stages to prevent phosphate losses.
BIORESOURCE TECHNOLOGY
(2021)
Article
Engineering, Environmental
Ambrogio Pigoli, Massimo Zilio, Fulvia Tambone, Stefania Mazzini, Micol Schepis, Erik Meers, Oscar Schoumans, Andrea Giordano, Fabrizio Adani
Summary: This study successfully transformed organic wastes into N fertilizers and organic fertilizers using high-solid thermophilic anaerobic digestion (HSAD). The produced fertilizers showed high nitrogen concentration, neutral pH, and readily available phosphorus, making them suitable for agricultural use as soil improvers.
Article
Agricultural Engineering
Wei Wang, Jo-Shu Chang, Duu-Jong Lee
Summary: The flourishing of anaerobic digestion highlights the importance of digestate valorization, which is crucial in determining the benefits of the process. Recently, digestate has gradually been perceived as a product rather than waste, in order to achieve the concept of a circular economy and maximize its benefits. Land application is the simplest way for valorization, but legislative restrictions and environmental concerns necessitate novel valorization methods. This review outlines the current methods for solid/liquid digestate valorization, nutrient recovery, microalgae cultivation, and integration with biological and thermochemical processes. The proposed novel valorization routes and their challenges and prospects are discussed, with the integration of anaerobic digestion and thermochemical methods showing potential market value for hydrochar/biochar-derived products.
BIORESOURCE TECHNOLOGY
(2023)
Article
Energy & Fuels
Taha Abdelfattah Mohammed Abdelwahab, Mahendra Kumar Mohanty, Pradeepta Kumar Sahoo, Debaraj Behera
Summary: The addition of iron nanoparticles (Fe NPs) was found to enhance biogas production and improve effluent chemical composition in anaerobic digestion of cattle manure. The optimal effect was achieved with 15 mg/L Fe NPs, leading to higher biogas production and methane yield compared to cattle manure alone. Furthermore, the addition of Fe NPs reduced hydrogen sulfide production.
BIOMASS CONVERSION AND BIOREFINERY
(2022)
Article
Environmental Sciences
Richard O'Shea, Richen Lin, David M. Wall, James D. Browne, Jerry D. Murphy
Summary: Increased biogas production has led to an oversupply of digestate applied to agricultural land, resulting in the need for long distance digestate transportation. This study evaluated the performance of three digestate management options – whole digestate application, digestate separation, and digestate separation with evaporation – combined with centralized or decentralized digestate storage.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Chemistry, Multidisciplinary
Marcin Debowski, Joanna Kazimierowicz, Marcin Zielinski
Summary: Chemical toilets are becoming more prevalent, especially in tourist destinations where waste treatment systems are lacking. In this study, the viability of anaerobic digestion for chemical toilet sewage (CTS) co-fermented with maize silage biomass was tested. It was found that CTS does not hinder anaerobic digestion as long as it is not more than 30% of the diluting fluid. The biogas yield reached 400 cm(3)/gVS, with 57 +/- 2.6% methane content.
APPLIED SCIENCES-BASEL
(2023)
Article
Agricultural Engineering
Daniel Pleissner, Astrid Victoria Lindner, Nicole Handel
Summary: The study explores the non-sterile heterotrophic cultivation of Galdieria sulphuraria in the presence of digestate and straw hydrolysate. Results indicate that proteolytic treatment of digestate can enhance growth rates and cell concentrations of G. sulphuraria, and the algae can utilize glucose obtained after straw hydrolysis. This research may offer promising strategies for utilizing agricultural waste streams to produce algal biomass rich in proteins.
BIORESOURCE TECHNOLOGY
(2021)
Review
Green & Sustainable Science & Technology
Madelaine Quiroz, Maria Teresa Varnero, Jaime G. Cuevas, Hugo Sierra
Summary: Opuntia ficus-indica, or cactus pear, has the potential to be a high-yielding energy crop for methane production through anaerobic digestion. Proper agronomic management is crucial for maximizing productivity and quality, with adjustments needed in raw material mixing, C/N ratio, and pH levels. Challenges remain in validating Opuntia as a sustainable energy source considering economic, social, and environmental factors.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Engineering, Environmental
Gaozhong Yang, Keda Jin, Mohamed Eraky, Jingjing Peng, Qiang Li, Liang Meng, Haorui Zhang, Ping Ai
Summary: The addition of Ca in anaerobic digestion can passivate the heavy metals in digestate. This study investigated the effects of different Ca compounds on the anaerobic digestion process and the speciation changes of Cu and Zn in SFD. It also explored the effects of applying Ca-containing SFD on Cu and Zn speciation changes in soil and the enrichment of Cu and Zn by ryegrass. The results showed that Ca(OH)2 addition facilitated the transfer of Cu and Zn from LFD to SFD, and SFD-Ca promoted biomass increase, inhibited Cu and Zn enrichment by ryegrass, and had the best passivation effect on Cu and Zn in soil.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Physical
S. S. Timofeeva, J. V. Karaeva, A. A. Kovalev, D. A. Kovalev, Yu. V. Litti
Summary: This study investigates the possibility of using steam gasification of digestates after anaerobic digestion and dark fermentation to obtain syngas with high hydrogen content. The syngas from digestates after dark fermentation has a high H2/CO ratio, making it promising for conversion to liquid fuel through Fischer-Tropsch synthesis. This research is significant for the processing of agricultural industrial waste and the production of high value-added products.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Environmental
Katarzyna Mikula, Krzysztof Trzaska, Dawid Skrzypczak, Grzegorz Izydorczyk, Ma lgorzata Mironiuk, Filip Gil, Mateusz Samoraj, Anna Witek-Krowiak, Katarzyna Chojnacka
Summary: Efficient nutrient cycling is crucial for sustainable agriculture, and using waste products from different industries can contribute to this process. This study explored the potential of using anaerobic digestate from food industry waste as a nutrient source for fertilizer production. Different sanitization methods were used, with acidic hydrolysate yielding a higher concentration of amino acids compared to alkaline. Granular fertilizers were formulated using various ingredients, and nitrogen balances were analyzed. The effectiveness of the fertilizers was evaluated through wheat germination tests, and the results indicated the potential of using anaerobic digestate for nutrient recycling in agroecosystems.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Engineering, Environmental
Barbara Lamolinara, Amaury Perez-Martinez, Estela Guardado-Yordi, Christian Guillen Fiallos, Karel Dieguez-Santana, Gerardo J. Ruiz-Mercado
Summary: Digestate is a nutrient-rich by-product from organic waste anaerobic digestion, but it can contribute to nutrient pollution without comprehensive management strategies. This study explores various aspects of digestate production, including feedstocks, processing technologies, economics, product quality, impurities, incentives, and regulations. The results indicate that feedstock, processing technology, and process operating conditions significantly influence the characteristics of digestate products. Incentive policies and regulations play a crucial role in promoting economic benefits. However, there is a lack of quality assurance certification systems for commercializing digestate products. Further development of technologies, processes, incentives, quality regulation, and social awareness is necessary for the sustainable and safe use of digestate in different applications. Future research should focus on circular business models and standardized international regulations for digestate products.
Review
Environmental Sciences
Andreia F. Santos, Paula Alvarenga, Licinio M. Gando-Ferreira, Margarida J. Quina
Summary: Water resources face global pressure, leading to scarcity and degradation of freshwater quality. European directives suggest that increasing the reuse of treated wastewater, reducing impacts on water bodies, and promoting water recycling can relieve pressure on water resources in urban areas. Besides addressing water supply challenges, wastewater treatment systems demonstrate environmental stewardship and innovative practices. The use of reclaimed water for agricultural irrigation is gaining interest, especially in drought-prone Europe, and it may restore nutrients to natural biogeochemical cycles. This review emphasizes the importance of water reuse, current legislation, and existing technologies in wastewater treatment systems for producing reclaimed water for agricultural irrigation.
Article
Biochemistry & Molecular Biology
Rafaela P. Rodrigues, Ana M. Sousa, Licinio M. Gando-Ferreira, Margarida J. Quina
Summary: The optimization of phenolic compounds extraction from grape pomace using solvents was studied. Ethanol and acetone were found to be the best solvents for extraction. The main extraction parameters were optimized using a central composite design. The optimized conditions for ethanol extraction were 60°C temperature, 1.5 hours extraction time, and 25 mL/gdryGP liquid-solid ratio. For acetone extraction, the optimal conditions were 50°C temperature, 1.5 hours extraction time, and 25 mL/gdryGP liquid-solid ratio. The yields of phenolic compounds were increased by three-stage extraction.
Article
Chemistry, Applied
Jonathan S. Cardoso, Zhi Lin, Paulo Brito, Licinio M. Gando-Ferreira
Summary: This article discusses the use of zeolites as fillers in mixed matrix membranes (MMMs) for gas separation. The difficulties in achieving high selectivity and low defects in the zeolite/polymer interface are well-documented. Researchers have found that functionalizing the zeolite surface with silane groups, amine groups, or ionic liquids improves the gas permeability and separation efficiency. This study focuses on a specific case of MMMs using SAPO-34 and compares surface modifications, proposing new membrane modifications and treatments.
SEPARATION AND PURIFICATION REVIEWS
(2023)
Review
Environmental Sciences
Joao R. F. Santos, Rafaela P. Rodrigues, Margarida J. Quina, Licinio M. Gando-Ferreira
Summary: Value-Added Compounds (VACs) in winery wastewater (WW) have potential for integration into existing processes or products. This study conducted a bibliometric analysis and literature review to explore the trends and strategies for recovery of VACs from WW. Membrane processes were identified as a promising technology, and the importance of circular economy and biorefinery in knowledge transfer was highlighted.
Article
Environmental Sciences
Maria Ines Roque, Joao Gomes, Igor Reva, Artur J. M. Valente, Nuno E. E. Simoes, Paula V. V. Morais, Luisa Duraes, Rui C. C. Martins
Summary: Ensuring drinking water quality is crucial for public health, especially in the context of increasing industrialization. Disinfection is a key process, but it leads to the formation of unwanted disinfection byproducts (DBPs) that negatively impact human health. Stricter regulations and techniques for DBP removal have been developed, but further research is needed to monitor and control these contaminants in water distribution systems.
Review
Green & Sustainable Science & Technology
Denner Deda, Helena Gervasio, Margarida J. Quina
Summary: Higher education institutions (HEI) worldwide are striving to assess and minimize their environmental impacts for sustainability. This paper conducts a bibliometric analysis to benchmark the sustainability of HEI in terms of key areas, impacts, and barriers. The analysis reveals that HEI have not systematically adopted life cycle assessment (LCA) in their assessments, with a primary focus on carbon emissions calculation. Lack of internal information and managerial commitment are the main barriers to LCA adoption in HEI.
Article
Green & Sustainable Science & Technology
Andreia D. Santos, Diana Goncalves, Rui C. Martins, Marta Gmurek, Anabela Nogueira, Sergio Castro-Silva, Luis M. Castro, Rosa Quinta-Ferreira
Summary: The increasing demand for fresh water requires industries to reduce the need for it, especially in the winemaking industry, which has a significant impact on water resources due to high water consumption and wastewater production. The sun-driven photooxidation process is widely used for wastewater treatment, and this study employed four photosensitizers to remove pollutants from wastewater for water reuse. Among the photosensitizers used, ZnPcS4 showed better removal of chemical oxygen demand (COD) and phenolic compounds (TPH). The study also evaluated the effect of pH and concentration on ZnPcS4, finding that alkaline solutions improved the removal efficiency but also caused bleaching of the photosensitizer.
Article
Chemistry, Physical
Eryk Fernandes, Pawel Mazierski, Tomasz Klimczuk, Adriana Zaleska-Medynska, Rui C. Martins, Joao Gomes
Summary: Graphitic carbon nitride (g-C3N4) catalysts were synthesized using melamine, urea, and thiourea as precursors, and their influence on photocatalytic performance was investigated. Urea-based catalyst (UCN) showed the best results under all radiation sources, followed by thiourea and melamine. UCN achieved higher degradation of parabens under UVA compared to visible light, while natural sunlight had the highest removals using UCN. UVA lamps consumed 45% less energy and costs. Photocatalytic ozonation using UCN and MCN showed superior performance and complete removal under 12 minutes.
Article
Biotechnology & Applied Microbiology
Sofia A. Vaz, Sara M. Badenes, Helena M. Pinheiro, Rui C. Martins
Summary: The conventional wastewater treatment process is being improved to reduce pollutant content in effluent. Microalgae cultivation on wastewater shows promise in both water purification and nutrient recovery. Further directing algal biomass to anaerobic co-digestion with wastewater sludge improves biogas yield and energy recovery. However, more data on the distribution of carbon, nitrogen, and phosphorus are needed for future studies.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2023)
Article
Biochemistry & Molecular Biology
Manorma Sharma, Patricia Alves, Licinio M. Gando-Ferreira
Summary: This study investigated the recovery of lignin from black liquor using nanofiltration. The highest lignin rejection rate was observed at a pressure of 12 bar. Furthermore, an economic evaluation showed that although the cost of nanofiltration membranes is relatively high, the process of recovering lignin and hemicellulose is economically feasible.
Article
Engineering, Environmental
B. S. Bandarra, C. Mesquita, H. Passos, R. C. Martins, P. A. L. F. Coelho, J. L. Pereira, M. J. Quina
Summary: This study evaluated the mechanical behavior and environmental hazardous potential of municipal solid waste incineration bottom ash (IBA), including ecotoxicity assessment, to explore its potential for safe utilization.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Environmental Sciences
Mariana Silva, Ines Oliveira-Inocencio, Rui C. Martins, Rosa Quinta-Ferreira, Marta Gmurek, Anabela Nogueira, Sergio Castro-Silva
Summary: In this study, the optimization of heterogeneous photosensitized oxidation treatment of winery effluents using chitosan carriers immobilized with Zn(II) Phthalocyanine tetrasulfonic acid was investigated. The effects of initial pH, aeration flow rate, photocatalyst load, and photosensitizer concentration on the treatment process were studied. The best reductions in COD and phenolic content (TPh) were achieved after 30 min of treatment in natural sunlight at an initial pH of 4.0 and an aeration flow rate of 2.8 L/min, with COD reduction of 45% and TPh reduction of 73%. The possibility of reusing the photocatalysts was also evaluated, and it was found that acidic pH allowed for their reuse without leaching of the photosensitizer.
Article
Environmental Sciences
Eva Domingues, Joao Lincho, Maria J. Fernandes, Joao Gomes, Rui C. Martins
Summary: Untreated swine wastewater can have serious consequences on water quality, but physical-chemical processes can effectively improve its quality. This study evaluated the performance of four low-cost materials and found that some of them showed promising results in removing COD. Additionally, the combination of adsorption and Fenton's process yielded interesting outcomes.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)