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The European Union has set ambitious targets of raising the share of EU energy consumption produced from renewable resources from 20% by 2020 to 27% by 2030. The aim of this paper is to assess the role of woody biomass in renewable energy as gross final energy consumption in the European Union (the EU-28). The paper identifies leading and lagging countries in biomass development by focusing on their current biomass use and forecasts future perspectives. The research compares and evaluates the role of biomass in renewable energy in the EU-28 focusing on countries' potential resources and policy support. The study shows that all countries are making efforts to reach the 20% target in 2020 and exhibit a trend of increasing renewable energy as gross final energy consumption towards the new target of 2030. Solid biomass plays an important role in reaching the EU's renewable energy targets. The majority of the EU-28 countries are close to reaching their national renewable energy targets and show a very attractive biomass development. Unless energy consumption decreases however, some member states will face serious problems in reaching their renewable energy target in 2020. Following our analysis, the largest problems occur in those MS having a relative high-energy consumption pattern: France, Germany and the United Kingdom. It is unlikely that they can comply with expected renewable energy demand, unless they mobilize more woody biomass from their available domestic potential (France, Germany) or considerably increase their woody biomass imports (mostly wood pellets) from elsewhere (United Kingdom).

Abstract The presence of hazardous trace elements (HTE) in the chemical recovery cycle of Kraft pulp mills is the main obstacle for the utilization of the inorganic residues of the process. Electrostatically precipitated (ESP) recovery boiler fly ash (RBFA), consisting mainly of sodium sulfate Na2SO4, is a solid side stream where HTE are concentrated. Unlike most other ashes, RBFA is to a great extent water-soluble. A novel reverse leaching method, based on the dissolution behavior of RBFA in water, is introduced in this paper. The method is founded on the use of an appropriate liquid/solid mass ratio and a favorable pH, which together contribute to the formation of a small and readily settling solid residue where almost all HTE are concentrated. This paper focuses on evaluating the influence of the treatment conditions on HTE removal, energy consumption and material losses. The results of this study show that the removal efficiency of the investigated HTE and other analyzed metals was excellent under alkaline conditions, the apparently suitable pH range for the removal of most of these metals being approximately 11.7–12.2. Lead was observed to be the most difficult HTE to remove: the highest obtained degree of removal of Pb was 89%. The removal rate of Cd and Zn was approx. 100% within the mentioned pH range.

Biomass torrefaction is a pre-treatment technology with high potential to convert biomass into a valuable commodity. The heat integration of torrefaction and combined heat and power (CHP) plant was investigated in previous work (Sermyagina et al., 2015). The aim of the present study is to assess possible economic benefits from integration. Three most promising integration concepts from the previous work were studied in terms of seasonal operational changes of district heating demand and varying ambient conditions. The performance of two integration concepts were evaluated together with stand-alone and co-located plants. The integration leads to a higher utilization of the CHP boiler capacity during part-load operation, possible increase of the operation time and growth of electricity generation as a result. The total efficiencies of the integrated cases (around 72% in higher heating value terms) are slightly higher than the stand-alone CHP plant (69%) or the co-located option (71%). The integration requires 40% more capital investments than the stand-alone CHP. On the other hand, the total capital investments of the integration cases are 20% lower than in co-located plants, and a profitability evaluation shows that lower investment costs may make integration schemes advantageous over the non-integrated plants. Feedstock price and investment costs are the main economic drivers affecting the profitability of the integrated options. An integration case which uses back pressure steam to account for the torrefaction heat demand showed the highest profitability due to a longer annual operating time, resulting in a growth of electricity and DH production over the stand-alone CHP plant.

AbstractCurrent biomass production and trade volumes for energy and new materials and bio‐chemicals are only a small fraction to achieve the bioenergy levels suggested by many global energy and climate change mitigation scenarios for 2050. However, comprehensive sustainability of large scale biomass production and trading has yet to be secured, and governance of developing biomass markets is a critical issue. Fundamental choices need to be made on how to develop sustainable biomass supply chains and govern sustainable international biomass markets. The aim of this paper is to provide a vision of how widespread trade and deployment of biomass for energy purposes can be integrated with the wider (bio)economy. It provides an overview of past and current trade flows of the main bioenergy products, and discusses the most important drivers and barriers for bioenergy in general, and more specifically the further development of bioenergy trade over the coming years. It discusses the role of bioenergy as part of the bioeconomy and other potential roles; and how it can help to achieve the sustainable development goals. The paper concludes that it is critical to demonstrate innovative and integrated value chains for biofuels, bioproducts, and biopower that can respond with agility to market factors while providing economic, environmental, and societal benefits to international trade and market. Furthermore, flexible biogenic carbon supply nets based on broad feedstock portfolios and multiple energy and material utilization pathways will reduce risks for involved stakeholder and foster the market entry and uptake of various densified biogenic carbon carriers. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd

Spargers are multi-hole injection pipes used in Boiling Water Reactors (BWR) and Advanced Pressurized (AP) reactors to condense steam in large water pools. A steam injection induces heat, momentum ...

The capacity to calculate and communicate the beneficial environmental impact of products and services is lacking in scientific guidelines. To fill this gap, this article presents a new approach for calculating the carbon handprint of products. The core of the suggested approach involves comparing the carbon footprint of an improved product with the carbon footprint of the baseline product, and subsequently calculating the reduction in greenhouse gas emission that can be achieved by utilizing the improved product. The proposed approach is founded on the standardized life cycle assessment methodology for footprints until the use stage, and it provides a framework to recognize the effects of the remaining life cycle stages in the actual operational environment. This calculation is meant to be used by manufacturers that wish to show potential customers the positive climate impacts offered by the manufacturer's product. The carbon handprint approach complements the existing methodologies by introducing new definitions and consistent guidelines for comparing the baseline product and the improved product. This article presents the developed calculation approach and demonstrates the approach with one case study about renewable diesel. Results of the diesel handprint calculation indicate that a driver can reduce greenhouse gas emissions by choosing renewable diesel over baseline fuel. Thus, the producer of the renewable diesel will create a handprint. Organizations can use carbon handprints for quantifying the greenhouse gas reductions their customers can achieve by utilizing the product. Thus, the carbon handprint can be a powerful tool in communications and marketing. By conducting carbon handprint assessments, a company can also find out how their product qualifies in comparison to baseline products. Therefore, carbon handprints can also support decision-making and lifelong product design.

Abstract The main objective of this work comprises the investigation of biodiesel production from rapeseed oil using potassium impregnated Fe3O4-CeO2 nanocatalyst. The various concentration of potassium impregnated Fe3O4-CeO2 was screened for catalytic conversion of rapeseed oil to triglyceride methyl ester. The 25 wt % potassium impregnated Fe3O4-CeO2 nanocatalyst showed best biodiesel production. Nanocatalyst was characterized by FTIR, XRD, SEM, TEM, BET and Hammett indicator for basicity test. The characterization of biodiesel was performed with GC-MS, 1H and 13C NMR. Moreover, the optimum reaction parameters such as catalyst amount (wt %), oil to methanol ratio, reaction time and reaction temperature for transesterification reaction was analyzed and yield was determined by 1H NMR. The maximum yield of 96.13% was obtained at 4.5 wt % catalyst amount, 1:7 oil to methanol ratio at 65 °C for 120 min. The properties of biodiesel such as acid value and kinematic viscosity were observed as 0.308 mg KOH/g and 4.37 mm2/s respectively. The other fuel parameters such as flash point and density were also determined. The reusability of catalyst was observed and it showed stability up to five cycles without considerable loss of activity. The recovery of excess methanol after transesterification reaction was achieved using distillation process setup.

Energy costs typically dominate the life-cycle costs of centrifugal compressors used in various industrial and municipal processes, making the compressor an attractive target for energy efficiency improvements. This study considers the achievable energy savings of using three different diffuser types in a centrifugal compressor supporting a typical end-use process in a waste water treatment plant. The effect of the energy efficiency improvements on the annual energy use and the environmental impacts are demonstrated with energy calculations and life-cycle assessment considering the selected compressor task in the waste water aeration. Besides the achievable energy saving benefits in the wastewater aeration process, the presented study shows the influence of the additional material needed in the diffuser manufacturing on the total greenhouse gas emissions of the compressor life-cycle. According to the calculations and assessment results, the studied diffuser types have a significant effect on the compressor energy use and environmental impacts when the compressor is operated in the aeration task. The achievable annual energy savings in this case were 2.5–4.9% in comparison with the baseline scenario. Also, the influence of the additional material and energy use for manufacturing the diffuser are insignificant compared with the avoided greenhouse gas reduction potential.

Abstract Direct contact condensation of steam bubbles in a boiling water reactor suppression pool has long been studied utilizing video recording of experiments. The use of video recording enables observation of the behaviour of the bubble surface area and can assist in validation of computational fluid dynamics models. A direct contact condensation experiment of the suppression pool test facility PPOOLEX was recorded using high-speed cameras. The recorded video material was used for development of a pattern recognition and data analysis algorithm. 300 fps video of 48 s duration was cut into frames with a resolution of 768 px × 768 px . The side profile of the bubbles was identified and the volumes and surface areas of the bubbles were evaluated using a voxel-based method. The purpose of the algorithm was to determine the shape and size of steam bubbles during their formation, expansion, collapse and re-formation. The most probabilistic chugging frequencies were estimated. The bubble geometry data were also used to determine the velocity and acceleration of the phase interface, as condensation induced Rayleigh-Taylor instability develops on the bubble surface during the bubble collapse, as the heavy phase accelerates towards the light phase. Knowledge of the critical wave length is necessary for mesh spacing in CFD calculations. The algorithm appears to be promising. Some limitations exist and approximations need to be made due to the challenging video shooting conditions. The algorithm works well for cylindrical bubbles and provides important data on the dynamics of the phase interface necessary for numerical modelling of direct contact condensation.

Abstract In order to achieve targets set by the Paris Agreement and limit global average temperature increase to well below 2 °C above pre-industrial levels, an assessment and a low carbon transformation is needed for all types of human activities. Cement production is associated with high levels of CO2 emissions, with an average of 866 kg of CO2 emitted per ton of cement produced. This positions the cement industry as one of the main sources of anthropogenic greenhouse gas emissions accounting for about 5% of the total, right after the chemical industry and more relevant than the iron and steel industry. About 50% of the emissions are caused by burnt fuel, related transport and other inputs, which can be currently substituted by other measures. However, the CO2 emissions which originate from input limestone cannot be avoided. These process CO2 emissions present a potential for carbon capture and utilisation. This research proposes a global potential analysis of CCU as a possible solution for the CO2 emissions of cement production. Cement CCU may establish a substantial route to use CO2 for synthetic hydrocarbons production and thus contribute towards mitigating the non-substitutable CO2 content of the limestone-based raw material. The production of renewable electricity based synthetic hydrocarbon fuels by CO2 captured from cement plants, counts for a potential to produce between 3639 TWhth and 7355 TWhth of liquid hydrocarbons, or 6298 TWhth and 12723 TWhth of synthetic natural gas, or a mix of both at the expected global cement peak production in 2040.