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• We present a novel integration for reducing CO 2 emissions in blast furnaces. • It combines top gas recycling, oxy-fuel regime, power to gas and biomass pyrolysis. • The integration was modelled using the extended operating line methodology. • The best performance was found for pyrolysis at 700 °C. • The CO 2 emissions were reduced by 58% (9.8 MJ/kg CO2 energy consumption) The paper introduces a novel approach for mitigating CO 2 emissions in blast furnaces by integrating top gas recycling, an oxy-fuel regime, power to gas, and biomass pyrolysis. Various case studies were conducted, involving the adjustment of pyrolysis temperatures (300 °C, 500 °C, 700 °C, and 900 °C) and varying the quantity of blast furnace gas directed to methanation for carbon recycling. Pinus radiata, abundant and cost-effective in Chile and Spain, was chosen as the biomass source. The integration was modeled using the extended operating line methodology and evaluated through 12 key performance indicators, such as flame temperature, coke consumption, CO 2 emissions, and specific primary energy consumption per unit of CO 2 avoided. Optimal performance was observed with pyrolysis at 700 °C and no blast furnace gas recycled through methanation. This configuration achieved a 58 % reduction in CO 2 emissions, with an energy consumption of 9.8 MJ/kg CO2 , and obviated the need for geological storage. Comparing this innovative proposal with other oxygen blast furnace approaches from the literature revealed a 13 percentage point improvement in CO 2 reduction over the second-best alternative. Additionally, the required electrolysis capacity, influencing capital expenditure, was 57 % lower, and energy consumption was reduced by 44 %. [ABSTRACT FROM AUTHOR]

• Novel control method of solar-assisted SMR with no thermal storage. • Designed system produces 148.6 tonne/d of H 2 with heat cogeneration rate of 1.28 MW. • Dried product output is 121 tonne/day, and 931.2 kW of power generation. • The estimated payback period of the proposed system is 9.4 years. • Daily-averaged energy and exergy efficiencies are 65.1% and 46.4%, respectively. This paper proposes a multigeneration plant to produce hydrogen, heat and power, and achieve product drying using the heat recovered from the solar-thermochemical system and a pyrolysis system where biomass and petroleum cokes are utilized to manage those sources for an environmentally benign operation. The developed system is then applied for a case study in the Kingdom of Saudi Arabia and uses three energy sources: biomass, petroleum coke and solar thermal energy. The biomass and petroleum coke blend is first hydro-gasified adiabatically, and then the product gas is steam-reformed in a reactor installed atop a solar tower of a large heliostat field. The steam-methane reactor is maintained hot and producing during nighttime by setting the reaction conditions to autothermal mode. Through the AspenPlus simulations performed, the optimum H 2 /C ratio in an adiabatic hydro-gasifier is found to be 1.5, which maximizes synthetic methane production at about 1300 °C. Most of the exergy destructions takes place in the system components, mainly the compressors with 53%, followed by the reactors with 38%, and heat exchangers with 9% at nighttime operation. The proposed system produces 148.6 tonne/d of H 2 with a heat cogeneration rate of 1.28 MW. Moreover, the dried product output is 121 tonnes/day and 931.2 kW of power generation. The average energy and exergy efficiencies of the present system for over a 24-hour period are obtained to be 65.1% and 46.4%, respectively. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present an improved way of collection and compilation of data about solid biomass consumption in households in order to improve accuracy of official energy statistics data. The accurate, timely and reliable energy data significantly contribute to the consistency in national energy statistics, energy balance, as well as for many other obligatory reporting procedures which are requested and prescribed by national and international standards. When compiling energy statistics, statistics on renewables, particularly biomass consumption, it is often the most questionable as little or no available official data exists in the country. According to the international standards and definitions, solid biomass covers organic, non-fossil material of biological origin which may be used as fuel for heat production or electricity generation. In households, the most commonly used biomass are fuelwood and wood residues. In the process of compiling national energy statistics, national institutions responsible for official energy statistics usually estimate biomass consumption based on the reports on fuelwood cuts in state forests and official biomass production, although it is known that consumption is much higher. Over the past two decades, Energy Institute Hrvoje Požar worked intensively on the energy consumption data collection and particularly on the development of the tailored-made surveying methods for different final energy consumption sectors, particularly for the household sector. The similar methods were recommended to national statistics institutes in the countries in the region when providing technical assistance in developing energy statistics. This paper describes the survey results and methods applied for the determination of energy consumption in households and particularly biomass consumption in three selected countries: Croatia, Bosnia and Herzegovina and Macedonia, and recommendations for the further improvements. [ABSTRACT FROM AUTHOR]

• An innovative hybrid solar-biomass system in a multi-family building was studied. • Deep reinforcement learning was applied to improve the control of the system. • Energy consumption was reduced by 35% in winter compared to a standard control. • No significant energy savings were obtained in summer despite innovative elements. Concerns related to climate change put renewable energy at the centre of most of the policies aimed at achieving a deep decarbonisation of the building sector. The combined use of two or more renewable energy sources in the same energy system can lead to an increase in the total share of renewable energy and in the flexibility of the system. In this direction, the SolBio-Rev project aims to develop an innovative system that uses solar thermal collectors and a biomass boiler to meet energy demand in buildings in different climatic regions. An advanced control that used deep reinforcement learning techniques was considered in this paper to find an optimal control strategy for a specific SolBio-Rev system installed in a standard multi-family residential building located in Madrid. The advanced control was developed to minimize the total cost of operation of the system. The results indicated that the advanced control strategy achieved a cost reduction of 35% in winter, compared to a standard rule-based control strategy. However, the improved control was not able to produce a significant cost reduction in summer. [ABSTRACT FROM AUTHOR]

Abstract: The increasing global energy demand and mounting pressures for CO2 mitigation call for increased efficient utilization of biomass, particularly for heating domestic and commercial buildings. The authors of the present paper are investigating the optimization of the combustion performance and NO x emissions of a 50kW biomass pellet boiler fabricated by a UK manufacturer. The boiler has a number of adjustable parameters including the ratio of air flow split between the primary and secondary supplies, the orientation, height, direction and number of the secondary inlets. The optimization of these parameters provides opportunities to improve both the combustion efficiency and NO x emissions. When used carefully in conjunction with experiments, Computational Fluid Dynamics (CFD) modelling is a useful tool for rapidly and at minimum cost examining the combustion performance and emissions from a boiler with multiple variable parameters. However, modelling combustion and emissions of a small-scale biomass pellet boiler is not trivial and appropriate fixed-bed models that can be coupled with the CFD code are required. This paper reviews previous approaches specifically relevant to simulating fixed-bed biomass boilers. In the first part it considers approaches to modelling the heterogeneous solid phase and coupling this with the gas phase. The essential components of the sub-models are then overviewed. Importantly, for the optimization process a model is required that has a good balance between accuracy in predicting physical trends, with low computational run time. Finally, a simple combustion model written within a FLUENT user defined function is described, together with the preliminary modelling results obtained for modelling the combustion of wood pellets in a 50kW fixed-bed biomass pellet boiler. [Copyright &y& Elsevier]

The aim of this work is to assess the feasibility of a Biomass Integrated Gasifier Fuel Cell (B-IGFC) plant. High temperature Solid Oxide Fuel Cells (SOFC) are the most efficient energy systems currently being developed and they show good fuel flexibility thanks to their high operational temperature. For the application here discussed, the fuel major active species are H 2 ,CO and CH 4 ; yet, in wood-derived syngas small amounts of higher hydrocarbons are produced too. Among them, tars are claimed to be biomass Achille’s heel, causing severe issues in internal combustion engines and turbines. Conversely, SOFCs might be able to decompose tars with a gain on cell performance. However, in order to avoid fast degradation, tars concentrations have to be below a critical threshold. In this work, SOFC operation with real wood syngas from a pilot batch gasifier is firstly demonstrated. Then, longer tests are repeated under controlled conditions, artificially reproducing wood syngas with and without tars. Tests demonstrated that commercial NiYSZ-anode cells are able to work on syngas with a model tar (toluene) concentration up to 10 g / N m 3 , exhibiting a voltage gain with regard to performances on syngas without model tar. No material degradation was observed after the experiments. As a final result, this paper aims at providing a proof of concept of a simplified B-IGFC system design, in order to reach its cost-effectiveness on small-scale installations. [ABSTRACT FROM AUTHOR]

This paper presents the consumption of energy needed to heat a detached house located in the north-east of Poland, as well as the cost of heat generation by combustion of wood briquettes compared to other biomass fuels and fossil fuels. The annual average consumption of briquettes during three heating seasons was 6.93–7.42 t/year and the annual consumption of fuel energy was 121–130 GJ/year. Expressed as energy per unit area of the house, the consumption of heat ranged from 0.40 to 0.42 GJ/m 2 /year. The average annual consumption of heat per person was 20.22–21.65 GJ. The annual cost of production of heat from briquettes for a house ranged from €772 to €986 during the three seasons under study. The cost of energy production from this fuel was much lower compared to fuel oil, natural gas, coal and pellets, but was higher compared to willow chips. Briquettes, which are produced in Poland in piston briquetting presses and which can be used as fuel in automatic boilers, is a prospective and promising feedstock for generating heat for family houses. The high price of new automatic biomass boilers is the main barrier in the modernisation of boiler houses. [ABSTRACT FROM AUTHOR]

Catalytic pyrolysisof biomass to prepare high-quality liquid fuels to assist carbon neutrality. [Display omitted] • The research progress of catalytic pyrolysis of biomass to produce liquid fuels and chemicals is reviewed. • The distribution of products is affected by raw materials, pretreatment, co-pyrolysis, reaction conditions. • The reaction mechanisms can be clarified from one-step, two-step and platform compounds transformation. • The advantages and limitations of various catalysts of biomass catalytic conversion are reviewed. • Catalytic conversion of biomass prospects and required further research are discussed. Considering the pressures of energy and the environment, using renewable resource—biomass to obtain hydrocarbon fuels and high-value chemicals has important application value and broad market prospects. However, due to the complex pyrolysis process of biomass, low calorific value, high oxygen content and strong acidity of bio-oil, the application of bio-oil as liquid fuel and chemicals are restricted. It is urgent to improve the quality of bio-oil. In this paper, the effects of biomass raw materials, pretreatment methods, co-pyrolysis of hydrogen donors and pyrolysis reaction conditions on the preparation of bio-oil by fast pyrolysis of biomass are described in detail. The article further discusses the research progress of biomass pyrolysis to prepare liquid fuel and high-value chemicals, including direct catalytic pyrolysis of biomass to prepare high-quality bio-oil, fast pyrolysis to prepare bio-oil and then catalytic upgrading, pyrolysis to prepare ketone and furan platform compounds, and then aldol condensation and catalytic hydrogenation. The main achievements and problems of three different synthesis techniques are reviewed objectively. Finally, the catalytic characteristics of catalysts are introduced by classification, and the specific applications and reaction mechanisms of different catalysts in catalytic pyrolysis, catalytic cracking and catalytic hydrogenation are systematically summarized, which provides a new direction for the research of lignocellulose biomass energy utilization. [ABSTRACT FROM AUTHOR]

Abstract: A great fraction of worldwide energy carriers and material products come from fossil fuel refinery. Because of the on-going price increase of fossil resources, their uncertain availability, and their environmental concerns, the feasibility of oil exploitation is predicted to decrease in the near future. Therefore, alternative solutions able to mitigate climate change and reduce the consumption of fossil fuels should be promoted. The replacement of oil with biomass as raw material for fuel and chemical production is an interesting option and is the driving force for the development of biorefinery complexes. In biorefinery, almost all the types of biomass feedstocks can be converted to different classes of biofuels and biochemicals through jointly applied conversion technologies. This paper provides a description of the emerging biorefinery concept, in comparison with the current oil refinery. The focus is on the state of the art in biofuel and biochemical production, as well as discussion of the most important biomass feedstocks, conversion technologies and final products. Through the integration of green chemistry into biorefineries, and the use of low environmental impact technologies, future sustainable production chains of biofuels and high value chemicals from biomass can be established. The aim of this bio-industry is to be competitive in the market and lead to the progressive replacement of oil refinery products. [Copyright &y& Elsevier]

This paper presents the results and analysis of a study conducted with the objective of investigating the cooking energy requirements in the Sri Lanka domestic sector and the environmental emissions associated with it.The study was conducted out through a sample and showed that the main household energy supply sources were biomass, liquefied petroleum gas (LPG), electricity and kerosene with electricity being used largely for water boiling in all subsectors. It was observed that the urban sector cooking is largely dominated by LPG (95% of urban households) while the rural sector cooking is confined mainly to biomass (95% of rural households). The suburban sector consists of a mixture of all the sources (LPG-70% and biomass-85% of suburban households). Similarly, LPG dominates in electrified households (76.4% of electrified households), while biomass dominates in all non-electrified households.It was found in the analysis that the highest level of gaseous emissions due to cooking activity occurs in the rural areas, mainly due to the relatively large use of biomass, while the lowest level of emissions is recorded in a typical suburban household. Also, the analysis shows that fuel switching in domestic cooking activities from biomass to LPG and kerosene can be used as a measure to reduce emissions due to higher stove efficiencies and lower emission factors associated with these fuels. Substitution of 50% of biomass usage by kerosene in the rural households will result in 39–50% reduction in emissions within the rural sector. Further, substitution of 50% of biomass usage in urban and suburban sectors by LPG results in 4–49% reduction in emissions within these sectors. [Copyright &y& Elsevier]