Showing papers on "Biogas published in 2020"
Journal Article•
TL;DR: A review of the turn of events and points of view of biogas in and its utilization for power, heat and in transport in the European Union (EU) and its Member States is presented in this article.
Abstract: This paper presents a review of the turn of events and points of view of biogas in and its utilization for power, heat and in transport in the European Union (EU) and its Member States. Biogas creation has expanded in the EU, empowered by the sustainable power strategies, notwithstanding monetary, ecological and atmosphere benefits, to arrive at 18 billion m3 methane (654 PJ) in 2015, speaking to half of the worldwide biogas creation. The EU is the world chief in biogas power creation, with more than 10 GW introduced and various 17,400 biogas plants, in contrast with the worldwide biogas limit of 15 GW in 2015. In the EU, biogas conveyed 127 TJ of warmth and 61 TWh of power in 2015; about half of absolute biogas utilization in Europe was bound to warm age. Europe is the world's driving maker of biomethane for the utilization as a vehicle fuel or for infusion into the petroleum gas network, with 459 plants in 2015 creating 1.2 billion m3 and 340 plants taking care of into the gas network, with a limit of 1.5 million m3. Around 697 biomethane filling stations guaranteed the utilization 160 million m3 of biomethane as a transport fuel in 2015.
703 citations
TL;DR: Four modes of pretreatment on lignocellulosic biomass and their impact on biogas production process is the major focus of this review article.
279 citations
TL;DR: The role of aerobic and anaerobic digestion technologies for the advancement of a bio-based circular society is explored and an emphasis was made on the innovative models for improved economics and process performance, which include co-digestion of various organic solid wastes, recovery of multiple bio-products, and integrated bioprocesses.
268 citations
TL;DR: The potential of biogas production from agricultural waste, its upgradation and utilization along with the government initiatives, policy regulations, and the future research opportunities to meet the growing needs for agri-waste management, energy production and climate change mitigation are discussed.
179 citations
TL;DR: In this article, the authors reviewed the innovations and optimizations in biogas production from the biological perspective reported by recently published patents and research works and categorized them into three different groups, i.e., upstream, mainstream, and downstream approaches.
175 citations
TL;DR: In this paper, a review of two-stage anaerobic digestion of food waste is presented, focusing on the parameters to be monitored and controlled for maximum performance, influence on efficiency and process stability.
Abstract: Two-stage anaerobic digestion is a substantial breakthrough in the field of renewable and sustainable energy technology that potentially transforms organic wastes into biohythane and simultaneously resolves the threat of energy crisis and waste disposal. Two-stage anaerobic system provides optimal process stability, increased energy efficacy and better control over crucial parameters governing assured performance and energy recovery. This review mainly focuses on the parameters to be monitored and controlled for maximum performance, influence on efficiency and process stability. The current findings and advanced research prospects in the field of two-stage anaerobic digestion of food wastes are analyzed. Increasing interest in utilizing this method for food waste management lies in understanding the influence of process parameters for maximal benefits.
157 citations
TL;DR: Mainstream biological techniques, bioaugmentation is highly advised to accelerate start-up periods at commercial scale while anaerobic co-digestion is recommended to not only enhance biogas yield throughout the operation but also to take advantage of different waste streams.
145 citations
TL;DR: In this paper, the authors presented an integrated techno-environmental assessment of hydrogen production from natural gas and biomethane, combined with CO2 capture and storage (CCS).
Abstract: This study presents an integrated techno-environmental assessment of hydrogen production from natural gas and biomethane, combined with CO2 capture and storage (CCS). We have included steam methane reforming (SMR) and autothermal reforming (ATR) for syngas production. CO2 is captured from the syngas with a novel vacuum pressure swing adsorption (VPSA) process, that combines hydrogen purification and CO2 separation in one cycle. As comparison, we have included cases with conventional amine-based technology. We have extended standard attributional Life Cycle Assessment (LCA) following ISO standards with a detailed carbon balance of the biogas production process (via digestion) and its by-products. The results show that the life-cycle greenhouse gas (GHG) performance of the VPSA and amine-based CO2 capture technologies is very similar as a result of comparable energy consumption. The configuration with the highest plant-wide CO2 capture rate (almost 100% of produced CO2 captured) is autothermal reforming with a two-stage water-gas shift and VPSA CO2 capture – because the latter has an inherently high CO2 capture rate of 98% or more for the investigated syngas. Depending on the configuration, the addition of CCS to natural gas reforming-based hydrogen production reduces its life-cycle Global Warming Potential by 45–85 percent, while the other environmental life-cycle impacts slightly increase. This brings natural gas-based hydrogen on par with renewable electricity-based hydrogen regarding impacts on climate change. When biomethane is used instead of natural gas, our study shows potential for net negative greenhouse gas emissions, i.e. the net removal of CO2 over the life cycle of biowaste-based hydrogen production. In the special case where the biogas digestate is used as agricultural fertiliser, and where a substantial amount of the carbon in the digestate remains in the soil, the biowaste-based hydrogen reaches net-negative life cycle greenhouse gas emissions even without the application of CCS. Addition of CCS to biomethane-based hydrogen production leads to net-negative emissions in all investigated cases.
137 citations
TL;DR: In this paper, a case study of the potential of using biochar and neutral red (phenazine) additives in one of the commercial landfills in the North Island of New Zealand was presented.
135 citations
TL;DR: In this paper, a critical and comprehensive review on the key issues and perspectives of microalgal biogas in terms of current knowledge and future developments is presented, which can draw a complete picture on microalgae and provide necessary perspectives for conducting further research efforts.
Abstract: Production of biogas from microalgae has been receiving significant attention since 1950s, as microalgae are capable of rapidly growing in the non-arable land area and accumulating high quantity of digestible macromolecules in the biomass. Nevertheless, commercial production of microalgae-based biogas is still in its immature stage for some existing technoeconomic challenges, as exemplified by the requirement of a costly and energy consuming step in biomass harvesting, recalcitrance of the components, low biomass loading rate, and interferences of various operational factors. Real-world research and developments are therefore necessary for achieving a state-of-the-art technology to produce microalgal biogas. In this context, extensive research efforts have been devoted since decades as attempts to improve efficiency and sustainability of this bioprocess. This paper presents a critical and comprehensive review on the key issues and perspectives of microalgal biogas in terms of current knowledge and future developments. Over the contemporary reviews published on this topical area, present paper distinctly covers almost all the relevant aspects, which might draw a complete picture on microalgal biogas and provide necessary perspectives for conducting further research efforts. Specifically, this paper discusses potentials of microalgae as the biogas feedstocks, screening and selection approaches of potent strains, technological aspects of microalgal biogas production, reactor design for anaerobic digestion (AD), operational conditions affecting AD, strategies for improving strains and biogas yield, biogas upgrading, kinetics, modelling and economics, life cycle assessment (LCA), and challenges coupled with further research opportunities.
134 citations
TL;DR: Anaerobic digestion from organic waste has gained worldwide attention in reducing greenhouse gas emissions, lowering fossil fuel combustion, and facilitating a sustainable renewable energy supply as discussed by the authors, however, the amount of organic materials currently available for biogas production is still limited.
Abstract: Anaerobic digestion (AD) from organic waste has gained worldwide attention in reducing greenhouse gas emissions, lowering fossil fuel combustion, and facilitating a sustainable renewable energy supply. Biogas mainly consists of methane (CH4) (50–75%), carbon dioxide (CO2) (25–50%), hydrogen sulphides (H2S), hydrogen (H2), ammonia (NH3) (1–2%) and traces of other gases such as oxygen (O2) and nitrogen (N2). Methane can replace fossil fuels in various applications such as heat and power generation and the transportation sector. The degradation of organic waste through an AD process offers many advantages, such as the decrease of pathogens and prevention of odour release. The digestate from anaerobic fermentation is a valuable fertilizer, however, the amount of organic materials currently available for biogas production is still limited. New substrates, as well as more effective conversion technologies, are needed to grow this industry globally. This paper reviewed the latest trends and progress in biogas production technologies including potential feedstock. Recycling of waste has recently become an important topic and has been explored in this paper.
TL;DR: A high flexibility of the biogas microbiome is highlighted, allowing it to modify its composition and to adapt to the environmental conditions, including temperatures and a wide range of substrates.
Abstract: Microorganisms in biogas reactors are essential for degradation of organic matter and methane production. However, a comprehensive genome-centric comparison, including relevant metadata for each sample, is still needed to identify the globally distributed biogas community members and serve as a reliable repository. Here, 134 publicly available metagenomes derived from different biogas reactors were used to recover 1635 metagenome-assembled genomes (MAGs) representing different biogas bacterial and archaeal species. All genomes were estimated to be > 50% complete and nearly half ≥ 90% complete with ≤ 5% contamination. In most samples, specialized microbial communities were established, while only a few taxa were widespread among the different reactor systems. Metabolic reconstruction of the MAGs enabled the prediction of functional traits related to biomass degradation and methane production from waste biomass. An extensive evaluation of the replication index provided an estimation of the growth dynamics for microbes involved in different steps of the food chain. The outcome of this study highlights a high flexibility of the biogas microbiome, allowing it to modify its composition and to adapt to the environmental conditions, including temperatures and a wide range of substrates. Our findings enhance our mechanistic understanding of the AD microbiome and substantially extend the existing repository of genomes. The established database represents a relevant resource for future studies related to this engineered ecosystem.
TL;DR: In this paper, the authors investigated some of the key factors in proposing food waste for anaerobic digestion, with particular reference to China and South East Asian countries, and found that food waste shows variable chemical composition and a high content of biodegradable material (carbohydrates, protein and lipid).
Abstract: Rapid economic growth in Asia and especially in China, will lead to a huge increase of food waste (FW) production that is expected to increase by 278–416 million tonnes. Among various waste management practices, anaerobic digestion (AD) is a useful method to transform food waste, producing renewable energy/biofuel and bio-fertilizers. This review aims to investigate some of the key factors in proposing FW for anaerobic digestion, with particular reference to China and South East Asian countries. Food waste shows variable chemical composition and a high content of biodegradable material (carbohydrates, protein and lipid). This composition led to consistent biogas production that was reported, as average for Chinese FW, of 480 ± 88 LCH4 kg−1 VS (n = 42). Since these data are higher than those reported for energy crops (246 ± 36 LCH4 kg−1 VS), this makes FW a good candidate to substitute for energy crops, avoiding food-energy conflicts. FW co-digestion with different substrates improved total bio-methane production (on average), from 268 ± 199 mL g−1 VS to 406 ± 137 mL g−1 VS. Food waste pretreatment, also, seems to be very useful in increasing total biogas production. Physical and thermal treatments were the best, increasing biogas production by 40% and 30%, respectively. Techno-economic evaluation seems to indicate the feasibility of substituting EC with FW for producing biogas and reducing total biomass costs. To achieve this, separate collection sources need to be put into place, assuring high FW quality to promote a Circular Economy approach in FW management.
TL;DR: An urban biorefinery technology chain has been developed at pilot scale in the territorial context of the Treviso municipality for the production of biopolymers and biogas from waste of urban origin and a preliminary insight into potential social acceptance and barriers regarding organic waste-derived products was obtained.
TL;DR: In this review, the most recent advances in UASB reactor applications are critically summarized and discussed, with outline on the most critical aspects for further possible future developments.
Abstract: Up-flow anaerobic sludge blanket (UASB) reactor belongs to high-rate systems, able to perform anaerobic reaction at reduced hydraulic retention time, if compared to traditional digesters. In this review, the most recent advances in UASB reactor applications are critically summarized and discussed, with outline on the most critical aspects for further possible future developments. Beside traditional anaerobic treatment of soluble and biodegradable substrates, research is actually focusing on the treatment of refractory and slowly degradable matrices, thanks to an improved understanding of microbial community composition and reactor hydrodynamics, together with utilization of powerful modeling tools. Innovative approaches include the use of UASB reactor for nitrogen removal, as well as for hydrogen and volatile fatty acid production. Co-digestion of complementary substrates available in the same territory is being extensively studied to increase biogas yield and provide smooth continuous operations in a circular economy perspective. Particular importance is being given to decentralized treatment, able to provide electricity and heat to local users with possible integration with other renewable energies. Proper pre-treatment application increases biogas yield, while a successive post-treatment is needed to meet required effluent standards, also from a toxicological perspective. An increased full-scale application of UASB technology is desirable to achieve circular economy and sustainability scopes, with efficient biogas exploitation, fulfilling renewable energy targets and green-house gases emission reduction, in particular in tropical countries, where limited reactor heating is required.
TL;DR: This study conducted a series of co-AD of different urban derived organic wastes in a semi-continuous mode, and the corresponding dynamic evolutions of microbial community structure were followed by using real-time quantitative polymerase chain reaction (qPCR).
TL;DR: Pyrolysis is an important thermochemical route to decompose lignocellulose biomass into biogas, bio-oil, and biochar, which can be then converted into value-added biofuels, chemicals, and biomateri...
Abstract: Pyrolysis is an important thermochemical route to decompose lignocellulose biomass into biogas, bio-oil, and biochar, which can be then converted into value-added biofuels, chemicals, and biomateri...
TL;DR: Recent developments in dry, bi-, and tri-reforming, where the CO2 in biogas is used as an oxidant/partial oxidant, are reviewed.
TL;DR: In this article, the authors provide an in-depth analysis of various biogas valorization methods (physical, chemical and biological) for its efficient and eco-friendly utilization.
TL;DR: In this article, the influence of solid loading on the composition of hydrochar and process water was studied, together with an evaluation of product yields, solubilisation of organic carbon and biomethane potential of process waters from HTC processing.
TL;DR: In this article, a review of the potential organic waste sources and the way in which the bioenergy is produced through efficient conversion processes is presented, focusing on providing a keen view on the potential organics sources and how they can be converted to bioenergy.
TL;DR: In this article, a review describes existing pretreatment processes for POME and recommends recently manufactured high-rate anaerobic reactors as the most suitable and efficient pretreatment technique for maximising the extraction of biogas from POME.
Abstract: Palm oil is one of the leading agricultural crops in the world, as it dominates 34% of the global vegetable oil market, with approximately 64.6*103 million kgs of production in 2017. However, along with its breakthrough, the generation of palm oil mill effluent (POME) as uncontrolled waste has become a serious matter and requires proper management to reduce its negative effects on the environment. Subsequently, the high organic content of POME makes it possible to convert waste into value-added products, such as biogas. A ratio of 0.5 for biological oxygen demand to chemical oxygen demand (BOD/COD) indicates a high possibility for biological treatment. Recently, the utilisation of POME as a cheap source for biogas production has gained an extraordinary amount of attention, and intensive research has been conducted on the upstream to downstream process. Finding the most suitable and efficient pretreatment technique and reactor configuration are vital parameters for the treatment and conversion of POME to biogas. This review describes existing pretreatment processes for POME and recommends recently manufactured high-rate anaerobic reactors as the most suitable and efficient pretreatment technique for maximising the extraction of biogas from POME.
TL;DR: In this article, the impact of interspecies electron transfer (DIET) via abiotic conductive materials and nanoscale materials on anaerobic digestion has been discussed and the positive and negative impacts of nanoscales on biogas production have been discussed.
TL;DR: In this article, the turning of food waste into biogas via anaerobic fermentation is widely recognized as the most efficient method for converting food waste to bio-diesel.
Abstract: Foodwaste (hereinafter, FW) is the most voluminous solid waste and its amount is growing rapidly all over the world. The turning of FW into biogas via anaerobic fermentation is widely recognized as...
TL;DR: In this article, the authors provided a detailed critical commentary on recent developments in cathode materials and their role in the bioconversion of methane and adopted efficient BES-AD designs.
TL;DR: In this paper, the authors present an overview of various thermo-chemical and biochemical routes that are being explored for the sustainable production of bio-methanol from waste biomass, and provide a brief account of their basic principles and also indicate the issues to be addressed through further technological upgradations for satiating the future energy demand.
TL;DR: In this paper, the authors summarized the developments in biogas design and operation, while highlighting the main factors that affect the efficiency of the anaerobic digestion process, and identified the negative conditions that should be avoided while operating a biOGas plant.
Abstract: The biogas production technology has improved over the last years for the aim of reducing the costs of the process, increasing the biogas yields, and minimizing the greenhouse gas emissions. To obtain a stable and efficient biogas production, there are several design considerations and operational parameters to be taken into account. Besides, adapting the process to unanticipated conditions can be achieved by adequate monitoring of various operational parameters. This paper reviews the research that has been conducted over the last years. This review paper summarizes the developments in biogas design and operation, while highlighting the main factors that affect the efficiency of the anaerobic digestion process. The study’s outcomes revealed that the optimum operational values of the main parameters may vary from one biogas plant to another. Additionally, the negative conditions that should be avoided while operating a biogas plant were identified.
TL;DR: P recovery from acid leaching of the hydrochar obtained at 180 °C, via precipitation with CaO at pH up to 9, led to a brown solid precipitate with total P content close to 42 mg g-1, in the range of low grade phosphorus ores, fairly interesting as solid fuels.
TL;DR: In this paper, the authors reviewed the feasibility of membrane separation for biogas upgrading by membrane separation and discussed gas permeation, membrane materials, membrane modules, multi-stage configurations, process configurations, and commercial biOGas plants.
Abstract: Global warming caused by increasing CO2 atmospheric levels is calling for sustainable fuels For instance, biomethane produced by biogas upgrading is a promising source of green energy Technologies to upgrade biogas include chemical absorption, water scrubbing, physical absorption, adsorption, cryogenic separation and membrane separation Historically, water scrubbing was preferred because of the simplicity of this operation However, during the last decade, membrane separation stood out due to its promising economic viability with investment costs of 3500–7500 €/(m3/h) and operational costs of 75–125 €/(m3/h) Here we review biogas upgrading by membrane separation We discuss gas permeation, membrane materials, membrane modules, process configurations and commercial biogas plants Polymeric materials appear as most adequate for membranes aimed to upgrade biogas Concerning membrane modules, hollow fibers are the cheapest (15–9 €/m2) Multistage configurations provide high methane recovery, of 99%, and purity, of 95–99%, compared to single-stage configurations
TL;DR: In this article, the authors compared the biogas status and related policies between China and Europe and tried to find the shortage and potential implications of the potential implications in order to promote China's Biogas industry development.
Abstract: In order to promote China's biogas industry development, this paper comprehensively compared the biogas status and related policies between China and Europe and tried to find the shortage and potential implications. China has access to abundant biomass resources, with considerable biogas potential and an annual theoretical output of 73.6 billion m3. Household-based biogas digesters coexist with medium and large-scale biogas plants (MLBPs) in China. Although the number of MLBPs in China was almost two times higher than Europe, the annul biogas production yield was only half of those in Europe. In China, biogas is mainly used for heating and cooking, and its power generation capacity is far lower than that in Europe. Overall, biogas industry is more commercialized in Europe than China. In terms of biogas related policies, China has an advantage in quantity, but is weak in their implementation. Biogas related policies in China mainly focus on agricultural and rural development, while in Europe, they are aimed at increasing the utilization of renewable energy and reducing greenhouse gas emissions. In addition, policies in China are mostly filled with encouragement, lacking detailed subsidy schemes and modes, whereas in European countries are more targeted and scientific. Based on the dissimilarity of current status and the disparity in policies, a series of countermeasures and suggestions for the development of the Chinese biogas industry are presented.