Optimization of Oxygen-based CFBC Technology with CO2 Capture

O2GEN project was running during more than three years and it was successfully finished in January 2016. The main target was to develop the 2nd generation oxyfuel circulating fluidized bed (CFB) power plants based on higher oxygen concentrations with the aim of decreasing flue gas recirculation and the energy penalty. Remarkable advances have been achieved in Air Separation (ASU) and Compression and Purification Units (CPU) reducing significantly their energy consumption. CFB boiler concept was proposed by scaling-up from past designs. No special drawbacks were found regarding combustion, heat transfer and emissions. Finally, a process integration methodology was applied and overall efficiency was increased by heat integration. Energy penalty was reduced from 10.5 to 7.3 efficiency points. The new power plant lay-out avoids technical restrictions in the use of complex heat exchangers and facilitates the operational flexibility of the system

Power to Gas-biomass oxycombustion hybrid system: Energy integration and potential applications

A promising hybridization which increases the chances of deployment of Power to Gas technology is found in the synergy with oxycombustion of biomass. This study assesses the efficiency of an energy integrated system under different sizes and potential applications. District heating and industrial processes are revealed as the most suitable potential applications for this hybrid technology. Global efficiency of the combined system may be increased through thermal energy integration. The relative increment of efficiency achieved for those designs which avoid the requirement of an air separation unit and for those which completely consumed the generated CO2, are 24.5% and 29.7% respectively. A 2 MWth district heating case study is also analysed, revealing that 81.2% of the total available heat from the PtG–oxy system could be integrated raising the global efficiency up to 78.7% at the adequate operational point. Further ‘full-fuel-cycle’ analysis will be required prior to decide the interest of the concept under a specific scenario in comparison to other available energy storage technologies

Power to Gas projects review: Lab, pilot and demo plants for storing renewable energy and CO2

Power to Gas (PtG) processes have appeared in the last years as a long-term solution for renewable electricity surplus storage through methane production. These promising techniques will play a significant role in the future energy storage scenario since it addresses two crucial issues: electrical grid stability in scenarios with high share of renewable sources and decarbonisation of high energy density fuels for transportation. There is a large number of pathways for the transformation of energy from renewable sources into gaseous or liquid fuels through the combination with residual carbon dioxide. The high energy density of these synthetic fuels allows a share of the original renewable energy to be stored in the long-term. The first objective of this review is to thoroughly gather and classify all these energy storage techniques to define in a clear manner the framework which includes the Power to Gas technologies. Once the boundaries of these PtG processes have been evidenced, the second objective of the work is to detail worldwide existing projects which deal with this technology. Basic information such as main objectives, location and launching date is presented together with a qualitative description of the plant, technical data, budget and project partners. A timeline has been built for every project to be able of tracking the evolution of research lines of different companies and institutions

Power to gas-electrochemical industry hybrid systems: A case study

Several researchers have proposed in literature different Power to Gas (PtG) hybridizations to improve the efficiency of this energy storage technology. Some of the synergies of this hybrid systems are already being tested under real conditions (e.g. PtG-Amine scrubbing, PtG-wastewater treatment) while others have only been studied through numerical simulations (e.g., PtG-oxyfuel combustion). Here, a novel hybridization between Power to Gas and electrochemical industries is proposed for the first time. This PtG-Electrochemical hybridization avoids to implement the typical water electrolysis stage of PtG since hydrogen is already available in the plant. This study thoroughly analyzes the implementation of Power to Gas in a real electrochemical plant that sub-produces hydrogen from the lines of production of chlorate, chlorine, and potassium hydroxide. It is shown that the required carbon dioxide for methanation can be captured from the flue gas of the factory''s boilers without additional energy penalty thanks to energy integration. The methanation plant has been designed according to the H2 and CO2 availability, taking into account the number of operating hours and the degree of usage of by-products. Results show that this PtG hybridization could operate more than 6000 h per year at large scale concepts (nominal H2 inputs of 2000 m3/h (NTP)), which represents 2000 h more than pilot/commercial demonstrations of classic PtG concepts. Besides, a detailed economic analysis demonstrates the economic feasibility of the system under current scenarios. It is shown that the capital investment would be recovered in 8 years, generating a 4.8 M€ NPV at the end of the project lifetime. Thus, this work presents a suitable way to avoid the subsidy dependency that current PtG research projects have

An operational approach for the designing of an energy integrated oxy-fuel CFB power plant

In order to increase the overall net electric efficiency and consequently to decrease the energy penalty in oxy-fired systems, heat integration configurations must be proposed. Coupling among the Air Separation Unit (ASU), the Compression and Purification Unit (CPU) and flue gases leaving the boiler becomes critical to obtain good efficiency figures. Many solutions have tried to show outstanding efficiency results but practical proposals are necessary to develop the technology. The use of flue gases waste energy to recycle flue gases heating up, oxygen preheating and increasing temperature of feedwater to steam cycle has been proposed to surpass the efficiency reduction. Nevertheless, care should be taken as potential problems would appear if only theoretical analysis is carried out. This work deals with a suitable and flexible design to increase the overall efficiency of an oxy-fuel combustion power plant working with high O2 concentration. Waste energy has been integrated avoiding any potential risk/damage into a new designed steam cycle. Applied solutions try to use lower cost proven materials in heat exchangers and simple equipment designs avoiding gas-gas heaters. Novel arrangements are presented, such as indirect heat exchangers, plastic heaters or different configurations integrating high pressure feedwater and low pressure condensate mass flows. Finally, results are compared with a previously optimized power plant design without operational restrictions and just a slight reduction in power plant net efficiency (less than 1%) was observed between both concepts

Power to Gas technology under Spanish Future Energy Scenario

Power to Gas (PtG) has been pointed out in the last years as a promising energy storage technology to smartly manage the renewable intermittent power generation that limits the operational flexibility of the network. In this work, we present a prospective study for the Spanish case, in which the implementation potential of PtG technology is evaluated in terms of the estimated renewable surpluses. We found that the annual surplus for the year 2050 would vary between 1.4 TWh and 5.2 TWh, and the PtG capacity required would be in the range 7.0 - 13.0 GW, depending on the renewable production pattern considered

D3.4 + D3.6: Annex 2 Results logistical case studies Aragon

In the S2Biom project the logistical case study in Burgundy was the first that wasperformed. The data were based on the results of the LogistEC project, which had already performed a thorough assessment of the case. Therefore, the S2Biom case study was especially used to develop the new tool LocaGIStics, and to illustrate the possibilities of such a new logistical tool in combination with an existing tool, the BeWhere model. So the results of the case study were not primarily intended to further assess the real life case or to advise an actual company for taking decisions on their biomass supply chain yet.The BeWhere model has been applied for the case study of Burgundy in order toidentify the optimal locations of bioenergy production plants. It should be emphasized that the locations of the plants were highly driven by the location and amount of the demand of heat over the transport collection of the feedstock at least for this particular case study. The collection points of the biomass are nevertheless very well concentrated around the production plants. Anyhow to validate those results, LocaGIStics is a valuable tool for the simulation of the feedstock collection from the plants determined from BeWhere. The quality check controls the feedstock collection, capacity and therefore the validity of the chosen location.The LocaGIStics model has especially been developed using the Burgundy casestudy. Several logistical concepts have been tested in the Burgundy case. These are:i) mixing different biomass types (straw as a biomass residue and Miscanthus as an energy crop), ii) applying pretreatment technology (pelletizing) to densify the material in order to lower the transportation costs and increase handling properties, iii) switching between different types of transport means (truck and walking floor vehicle)and iv) direct delivery to a power plant versus putting an intermediate collection point in the value chain. Due to the nature of this development case less value should be given to the exact results of the five variants that are described in this report. However, these variants are perfect examples of what effects can be achieved if the set-up of a lignocellulosic biomass value chain is changed, even if that change is only slightly. So the case was used successfully to build a first version of the locaGIStics tool. However, many improvements are still possible and could be achieved in future project cases

D3.4 + D3.6: Cover report Results logistical case studies

The S2Biom project - Delivery of sustainable supply of non-food biomass to support a “resource-efficient” Bioeconomy in Europe - supports the sustainable delivery of nonfood biomass feedstock at local, regional and pan European level through developing strategies, and roadmaps that will be informed by a “computerized and easy to use” toolset (and respective databases) with updated harmonized datasets at local, regional, national and pan European level for EU28, Western Balkans, Moldova, Turkey and Ukraine. A case based approach was followed, where optimal logistical concepts (conceptual designs) were matched with the specific regional situation. This was done in three logistical case studies that were performed: 1. Small-scale power production with straw and Miscanthus in the Burgundy region (France); 2. Large-scale power production with straw and with residual woody biomass in the Aragon region (Spain); 3. Advanced wood logistics in the Province of Central Finland

Results logistical case studies

S2Biom project grant agreement n 60862

D3.4 + D3.6: Cover report Results logistical case studies

The S2Biom project - Delivery of sustainable supply of non-food biomass to support a “resource-efficient” Bioeconomy in Europe - supports the sustainable delivery of nonfood biomass feedstock at local, regional and pan European level through developing strategies, and roadmaps that will be informed by a “computerized and easy to use” toolset (and respective databases) with updated harmonized datasets at local, regional, national and pan European level for EU28, Western Balkans, Moldova, Turkey and Ukraine. A case based approach was followed, where optimal logistical concepts (conceptual designs) were matched with the specific regional situation. This was done in three logistical case studies that were performed: 1. Small-scale power production with straw and Miscanthus in the Burgundy region (France); 2. Large-scale power production with straw and with residual woody biomass in the Aragon region (Spain); 3. Advanced wood logistics in the Province of Central Finland