Recent Perspectives in Pyrolysis Research

Recent Perspectives in Pyrolysis Research presents and discusses different routes of pyrolytic conversions. It contains exhaustive and comprehensive reports and studies of the use of pyrolysis for energy and materials production and waste management

Energetic valorisation of agricultural by‐products in the sub‐Saharan zone: Biomass pre‐conditioning via flash pyrolysis

Sub-Saharan West Africa lacks of natural resources, especially for energy production. By-products of agro-industry as cashew nut shells (CNS), jatropha (Jc) and shea (Sc) press cakes were identified as available resources for energetic valorisation. These biomasses are characterised by high extractive contents (cashew nut shell liquid/CNSL or triglycerides) which are the reason for toxic fumes during combustion. The thesis investigated the feasibility of flash pyrolysis as alternative process for these resources, more specifically the impact of the extractives on yields, the composition and the stability of flash pyrolysis oils. The feedstock were derived into samples covering the whole range of extractive contents (from de-oiled press cakes, ~0 wt%; to pure extractives, 100 wt%) which were characterised and pyrolysed in two laboratory devices (TGA and tubular furnace), then by applying flash pyrolysis conditions in a fluidised bed reactor. No significant interaction in-between the solid matrix and the extractives during pyrolysis were observed but different products were identified. CNSL volatises between 250 and 320°C, several phenolic compounds and typical compounds of crude CNSL were found to be present in the pyrolysis oil. In contrast, triglycerides are entirely decomposed at 380 to 420°C to give linear hydro-carbon chains. Some interaction products of the triglycerides with proteins were identified. Additionally, the experiments with the pilot plant have shown operational difficulties in the fluidised bed, which are linked to specific properties of the press cakes. Thus, further optimisations of process conditions are suggested. To overcome the observed phase separation of the pyrolysis oils mixtures with other biofuels were studied. The obtained emulsions are more homogeneous but the physical stability is still insufficient despite the addition of surfactants. (Résumé d'auteur

Upgrading of bio-oil from palm empty fruit bunch fibre with non-acidic oxides via catalytic intermediate pyrolysis

In response to the concerns regarding environmental pollution and energy security, renewable energy has been perceived as a solution. As liquid fuel is the most consumed form of energy in the world, much attention has been paid to pyrolysis for the production of bio-oil. Bio-oil may be derived from biomass and is a potential fuel supplement and source of chemicals. However, lignocellulosic biomass-derived bio-oil is generally highly acidic and highly oxygenated than crude oil. Consequently, the bio-oil is unstable and has a comparatively low energy density. Hence, bio-oil has to be upgraded in order to use directly as fuel and other applications. One of the upgrading methods is catalytic pyrolysis using non-acidic oxides. The current project investigated the effects of calcium oxide (CaO), magnesium oxide (MgO), and zinc oxide (ZnO) on the upgrading of palm empty fruit bunch fibre (EFBF)-derived bio-oil. Apart from that, cellulose was used as feed to study the effects of the oxides on lignocellulosic biomass at its simplest form upon intermediate pyrolysis. The possible reaction pathways involved upon the utilization of the oxides were also summarized. Thermogravimetric studies revealed that the addition of MgO and ZnO did not affect the degradation behaviour of both cellulose and EFBF. However, because CaO is prone to adsorb moisture and carbon dioxide (CO2), an additional weight loss stage was observed. Even though the oxides did not affect the activation energy and mechanism of EFBF devolatilization, the amount of volatiles released reduced due to the restriction posed by the oxides. Despite the catalytic effects posed by the oxides, the reaction of the oxides with CO2 and water categorizes CaO, MgO, and ZnO as catalytic additives, rather than catalysts. Based on the results obtained when cellulose was used as feed, the reaction pathways involved in the catalytic upgrading of bio-oil were compiled. Nevertheless, upon comparing the results of the results with literature, it was concluded that the results may be used as a reference of the reactions involved during catalytic pyrolysis of biomass but it may not exactly reflect the absolute effects of the oxides on the physical properties of all bio-oils. All three oxides showed evidence in enhancing the physical properties of cellulose and EFBF-derived bio-oil, in terms of reducing the amounts of acids and oxygenated compounds. However, the oxides reacted with carbon dioxide (CO2) and water. Hence, the oxides may be considered as catalytic additives rather than as catalysts. Among the three oxides, CaO exhibited the best performance in the matter of reducing the acidity for both cellulose and EFBF-derived bio-oils, without affecting the bio-oil yield substantially. CaO also showed potential in stabilizing the EFBF-derived bio-oil without influencing the surface structure of the bio-oil

Upgrading of bio-oil from palm empty fruit bunch fibre with non-acidic oxides via catalytic intermediate pyrolysis

In response to the concerns regarding environmental pollution and energy security, renewable energy has been perceived as a solution. As liquid fuel is the most consumed form of energy in the world, much attention has been paid to pyrolysis for the production of bio-oil. Bio-oil may be derived from biomass and is a potential fuel supplement and source of chemicals. However, lignocellulosic biomass-derived bio-oil is generally highly acidic and highly oxygenated than crude oil. Consequently, the bio-oil is unstable and has a comparatively low energy density. Hence, bio-oil has to be upgraded in order to use directly as fuel and other applications. One of the upgrading methods is catalytic pyrolysis using non-acidic oxides. The current project investigated the effects of calcium oxide (CaO), magnesium oxide (MgO), and zinc oxide (ZnO) on the upgrading of palm empty fruit bunch fibre (EFBF)-derived bio-oil. Apart from that, cellulose was used as feed to study the effects of the oxides on lignocellulosic biomass at its simplest form upon intermediate pyrolysis. The possible reaction pathways involved upon the utilization of the oxides were also summarized. Thermogravimetric studies revealed that the addition of MgO and ZnO did not affect the degradation behaviour of both cellulose and EFBF. However, because CaO is prone to adsorb moisture and carbon dioxide (CO2), an additional weight loss stage was observed. Even though the oxides did not affect the activation energy and mechanism of EFBF devolatilization, the amount of volatiles released reduced due to the restriction posed by the oxides. Despite the catalytic effects posed by the oxides, the reaction of the oxides with CO2 and water categorizes CaO, MgO, and ZnO as catalytic additives, rather than catalysts. Based on the results obtained when cellulose was used as feed, the reaction pathways involved in the catalytic upgrading of bio-oil were compiled. Nevertheless, upon comparing the results of the results with literature, it was concluded that the results may be used as a reference of the reactions involved during catalytic pyrolysis of biomass but it may not exactly reflect the absolute effects of the oxides on the physical properties of all bio-oils. All three oxides showed evidence in enhancing the physical properties of cellulose and EFBF-derived bio-oil, in terms of reducing the amounts of acids and oxygenated compounds. However, the oxides reacted with carbon dioxide (CO2) and water. Hence, the oxides may be considered as catalytic additives rather than as catalysts. Among the three oxides, CaO exhibited the best performance in the matter of reducing the acidity for both cellulose and EFBF-derived bio-oils, without affecting the bio-oil yield substantially. CaO also showed potential in stabilizing the EFBF-derived bio-oil without influencing the surface structure of the bio-oil

Conceptual design of alternative energy systems from biomass

El sector energético se está dirigiendo hacia un nuevo paradigma, favoreciendo la aparición de procesos de conversión más eficientes, el uso de las fuentes de energía renovables y la micro-generación. La bioenergía es una solución prometedora para la futura combinación de energías. Los conceptos de ingeniería deben de integrarse junto con los aspectos económicos, ambientales y sociales en el desarrollo de proyectos. Los sistemas de energía centralizados y distribuidos necesitan enfoques a medida para explotar las características de cada posible sistema. Esta tesis investiga el potencial del sector bioenergético, mediante el estudio de la gasificación de biomasa a través de técnicas avanzadas de modelización de procesos y de la incorporación de la gestión de la cadena de suministro, en el marco del diseño conceptual para la toma de decisiones. Los sistemas estudiados son: (i) gasificación integrada con ciclo combinado y con métodos de captura y almacenamiento de CO2 (IGCC-CCS, 285 MWe) para los sistemas de energía centralizados, y (ii) un gasificador de biomasa combinada con un motor de gas (BG-GE, 14 kWe) para los sistemas de energía distribuidos. La superestructura concebida puede ser utilizada en el diseño preliminar de alternativas para los diferentes procesos considerados, para adaptar los ya existentes y para adquirir conocimiento sobre las condiciones de operación de plantas de gasificación. El problema de optimización multi-objetivo considerado evalúa el equilibrio entre los criterios técnico-económicos y ambientales de 25 escenarios, con mezclas de diferentes materias primas y cambios topológicos: mezclas de carbón, coque y biomasa y la generación de electricidad a partir de gas de síntesis, la generación de electricidad a partir de H2 y la producción de H2 puro, considerando o no el uso del gas de purga del PSA en el ciclo combinado. El análisis de Pareto revela que como mejores escenarios el que utiliza coque de petróleo como materia prima para producir H2, con reciclo del gas de purga del PSA y el que utiliza biomasa residual sin reaprovechamiento del gas de purga del PSA. La implementación de la tecnología CCS conlleva una penalización en la eficiencia de un 8,7% en términos de potencia neta, si el H2 se utiliza en el ciclo combinado. La gestión de cadenas de suministro de sistemas centralizados, señalan que España tiene potencial de biomasa residual, invirtiendo en nuevas centrales IGCC-CCS, o para producir electricidad mediante co-combustión en las centrales térmicas de carbón ya existentes. Para el primer caso, el valor actual neto óptimo es 230 millones de € para un periodo considerado de 25 años. Para el segundo caso, se ha calculado que las políticas de subvención en este tipo de proyectos deben de tener en cuenta la sostenibilidad económica, cubriendo en un rango de 5,84% a 20,25% el aumento de los precios de la electricidad. El caso de estudio propuesto y optimizado como ejemplo de un sistema distribuido tiene en cuenta una comunidad de Ghana en el marco de la electrificación rural, a abastecer con peladuras de yuca y mediante sistemas BG-GE. Los resultados revelan una red inviable. De las cadenas de suministro resultantes como óptimas, se puede deducir que cierto nivel de centralización es necesario para que las propuestas sean sostenibles en el tiempo. El sector de la bioenergía cumple ofrece ventajas en términos de impacto ambiental y social. Su implementación es posible con el apoyo de las tecnologías actuales de conversión de energía. Los principales retos están en la mejora de los procesos de pretratamiento de la biomasa y en su almacenamiento. La conversión de la biomasa, junto con los métodos de captura y almacenamiento de CO2, necesitan de incentivos políticos para poder penetrar definitivamente en el mercado, como sería el caso de cualquier otra tecnología alternativa de conversión de energíaThe energy sector faces a new energy paradigm, with more efficient conversion processes, renewable sources and micro-generation. Bioenergy is a promising solution. Engineering aspects must be integrated with economic, environmental and social aspects in bioenergy projects. Biomass properties enhancement is crucial. It concerns energy and matter densifications, for stabilisation and easier transport. Tailor-made approaches are needed to account for the characteristics of each potential system, being it centralised or distributed. This thesis has assessed the bioenergy potential using advanced modelling techniques, enlarged with supply chain management strategies, in the framework of conceptual design for decision-making. The studied energy systems are (i) an integrated gasification combined cycle power plant combined with carbon capture and storage (IGCC-CCS, 285 MWe) for centralised energy systems, and (ii) a biomass gasifier with a gas engine (BG-GE, 14 kWe) for distributed energy systems. Process system modelling and optimisation approaches are integrated with supply chain management to analyse co-gasification and co-production of electricity and hydrogen alternatives in IGCC-CCS, and co-combustion of biomass and coal in pulverised coal power plants in the light of economic and environmental considerations. Process modelling is integrated with supply chain management optimisation for rural electrification by BG-GE systems, considering economic, environmental and social issues. The superstructure can be used for the design of process alternatives, retrofit of existing ones and to gain knowledge on operation of IGCC-CCS. The multi-objective optimisation problem evaluates the trade-off between techno-economic and environmental criteria of 25 scenarios. Considerations comprise different coal, petcoke and biomass combinations and electricity generation from syngas, electricity generation from H2 and purified H2 production without and with PSA purge gas use in the combined cycle. The Pareto frontier analyses reveals that the scenario with petcoke as feedstock for H2 production with PSA flue gas profit is the best in terms of techno-economic optimisation. The scenario with residual biomass without PSA flue gas profit is the best in terms of environmental optimisation. CCS technology implementation leads to an efficiency penalty of 8.7% in net power terms if H2 is used in the IGCC. To maintain the same power level than that obtained with the combustion of syngas, the feedstock should be increased by 21% on a mass basis. Supply chain studies highlight, for Spain, a huge biomass waste potential for electricity and H2 production by investing on new IGCC-CCS power plants, or adaptation of existing plants. For the first case, the optimal NPV is around 230M€ for a period of 25 years. The sensitivity of the optimal solutions to changes in prices is demonstrated. For the second case, policy subsidies or alternatively price increases range from 5.84% to 20.25%. The investment is within 549M€ and 1640M€. A supply chain in a specific community from Ghana is proposed for rural electrification using cassava peels. Optimisations considers 9 communities and an overall electricity demand of 118 MWh/yr. The results reveal an unviable network. From the resulting networks, distributed approaches need a certain level of centralisation to be feasible on time. Bioenergy offers decisive advantages in terms of environmental and social impacts. Its deployment is straightforward to support with current energy conversion technologies. Challenges concern the biomass pre-treatment and storage. Despite all the striking advantages, political incentives are needed for definitive market entry, as would be the case for any energy conversion alternative.Postprint (published version

Experimental investigation and modelling of the heating value and elemental composition of biomass through artificial intelligence

Abstract: Knowledge advancement in artificial intelligence and blockchain technologies provides new potential predictive reliability for biomass energy value chain. However, for the prediction approach against experimental methodology, the prediction accuracy is expected to be high in order to develop a high fidelity and robust software which can serve as a tool in the decision making process. The global standards related to classification methods and energetic properties of biomass are still evolving given different observation and results which have been reported in the literature. Apart from these, there is a need for a holistic understanding of the effect of particle sizes and geospatial factors on the physicochemical properties of biomass to increase the uptake of bioenergy. Therefore, this research carried out an experimental investigation of some selected bioresources and also develops high-fidelity models built on artificial intelligence capability to accurately classify the biomass feedstocks, predict the main elemental composition (Carbon, Hydrogen, and Oxygen) on dry basis and the Heating value in (MJ/kg) of biomass...Ph.D. (Mechanical Engineering Science

Porous Materials for Environmental Applications

The development of porous materials has attracted the attention of the research community for years. Porosity characteristics have specific impacts on the material properties and materials that are applied in many areas, such as pollutant removal, CO2 capture, energy storage, catalytic oxidation and reduction processes, the conversion of biomass to biofuels, and drug delivery. Examples of porous materials are activated carbons, clays, and zeolites. The aim of this book is to collect the recent advances and progress regarding porous materials and their applications in the environmental area

Gas, Water and Solid Waste Treatment Technology

This book introduces a variety of treatment technologies, such as physical, chemical, and biological methods for the treatment of gas emissions, wastewater, and solid waste. It provides a useful source of information for engineers and specialists, as well as for undergraduate and postgraduate students, in the areas of environmental science and engineering

WP3 – Innovation in Agriculture and Forestry Sector for Energetic Sustainability

The papers published in this Special Issue “WP3—Innovation in Agriculture and Forestry Sector for Energetic Sustainability” bring together some of the latest research results in the field of biomass valorization and the process of energy production and climate change and other areas relevant to energetic sustainability [1–20]. Moreover, several works address the very important topic of evaluating the safety aspects for energy plant use [21–24]. Responses to our call generated the following statistics:• Submissions (21);• Publications (15);• Rejections (6);• Article types: research articles (13), reviews (2). Of the submitted papers, 15 have been successfully published as articles. Reviewing and selecting the papers for this Special Issue was very inspiring and rewarding. We also thank the editorial staff and reviewers for their efforts and help during the process. For better comprehension, the contributions to this Special Issue are divided into sections, as follows

Adsorbents for Water and Wastewater Treatment and Resource Recovery

Adsorption is a well-established operation used for water decontamination and the remediation of industrial effluents. It is also recognized as a key technology for recovering substances of economic interest or those at risk of scarcity. The new sustainability paradigm of the circular economy and the current context of promoting the efficient use of natural resources, water and energy have been motivating the search for eco-friendly adsorbents for water and wastewater treatment and resource recovery. This Special Issue compiles 21 papers (17 research articles and 4 reviews), addressing the removal of heavy metals, toxic metalloids, precious metals and organics from aqueous solution, using a wide variety of adsorbents derived from natural and waste materials