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Fire risk analysis of electric vehicles and internal combustion vehicles in open car parks: part 2: fire safety and reliability analysis In order to counteract climate change, it is necessary to switch from vehicles with combustion engines to electric vehicles. Consequently, an increasing number of electric vehicles can be observed in Germany. In this context, the question arises whether and if how this development influences the fire risks in open car parks. Answers to this question are the subject of a research project under the leadership of the Institute of Steel Construction of Leibniz University Hannover in cooperation with the iBMB, Division of Fire Safety, of TU Braunschweig. In particular, the project is investigating the influence of a fire scenarios with electric vehicles compared to vehicles with combustion engines on the load‐bearing behaviour structure of an open car park. In this paper, the methodological approach to evaluate the fire risk based on a reliability analysis for the load‐bearing structure of these car parks is explained. By means of the reliability analysis, the fire risk assessment procedure is illustrated for the composite beam using exemplary fire scenarios. As a result, it can be concluded from the fire risk analysis that fire scenarios with electric vehicles do not have a higher fire risk than conventional vehicles with combustion engines and fulfil the required safety level. [ABSTRACT FROM AUTHOR]

On a cold single-phase test stand, the effect of central air on the exit flow field of Babcock, Germany, burner was investigated. Industrial measurements were taken for a 700 MW wall-fired pulverized-coal utility boiler with above burners. Gas temperature, gas composition and concentration in the burner area were measured at 444 MW, 522 MW and 645 MW loads, respectively. Only when the central air mass flow was zero did a center reflux zone exist in the burner outlet area. The steady combustion of faulty coal was aided by early mixing of primary and secondary air, which was made possible by the decreased central air mass flow. At all different loads, the pulverized coal in center region took a long distance to ignite. The temperature in center steadily dropped as central air mass flow decreased, while the temperature in secondary air region gradually rose. Within 1.5 m from the primary air duct outlet, the highest CO concentration was 25 ppm and the highest O2 concentration was close to 21% under all loads. The gas concentration near sidewall was more influenced by load. With all valves opening of burner center air at 30%, the boiler was able to operate safely and stably without oil at a load of 262 MW. The furnace chamber temperature in burner area reached 1056.1 °C. [ABSTRACT FROM AUTHOR]

In view of the tremendous emissions of toxic gases and particulate matter (PM) by low-power firewood-fueled fireplaces, there is an urgent need for effective measures to lower emissions to keep this renewable and economical source for private home heating available in the future. For this purpose, an advanced combustion air control system was developed and tested on a commercial fireplace (HKD7, Bunner GmbH, Eggenfelden, Germany), complemented with a commercial oxidation catalyst (EmTechEngineering GmbH, Leipzig, Germany) placed in the post-combustion zone. Combustion air stream control of the wood-log charge combustion was realized by five different control algorithms to describe all situations of combustion properly. These control algorithms are based on the signals of commercial sensors representing catalyst temperature (thermocouple), residual oxygen concentration (LSU 4.9, Bosch GmbH, Gerlingen, Germany) and CO/HC-content in the exhaust (LH-sensor, Lamtec Mess- und Regeltechnik für Feuerungen GmbH & Co. KG, Walldorf (Germany)). The actual flows of the combustion air streams, as calculated for the primary and secondary combustion zone, are adjusted by motor-driven shutters and commercial air mass flow sensors (HFM7, Bosch GmbH, Gerlingen, Germany) in separate feedback control loops. For the first time, the residual CO/HC-content (CO, methane, formaldehyde, etc.) in the flue gas is in-situ monitored with a long-term stable AuPt/YSZ/Pt mixed potential high-temperature gas sensor, which allows continuous estimation of the flue gas quality with an accuracy of about ±10%. This parameter is not only an essential input for advanced combustion air stream control but also provides monitoring of the actual combustion quality and logging of this value over a whole heating period. By many firing experiments in the laboratory and by field tests over four months, it could be demonstrated that with this long-term stable and advanced automated firing system, depression of the gaseous emissions by about 90% related to manually operated fireplaces without catalyst could be achieved. In addition, preliminary investigations at a firing appliance complemented by an electrostatic precipitator yielded PM emission depression between 70% and 90%, depending on the firewood load. [ABSTRACT FROM AUTHOR]

Summary: Obviously, the use of insulation materials from renewable resources in buildings could provide benefits regarding environmental protection and sustainable management. Nevertheless, their market share in Germany is estimated to be about 7% because of a partial lack of knowledge about their properties, and therefore, of construction certifications. This work was intended to close a knowledge gap concerning emissions during pyrolysis, smoldering, and combustion of commercial insulating materials made from wood, cellulose, meadow grass, hemp, jute, cork, and seaweed as well as polystyrene for comparison reasons. Laboratory‐scale experiments were conducted and the measurement of thermal decomposition products was done with gas chromatography combined with mass spectrometry (GC/MS). It was realized that almost all the products could be assigned to the following eight substance classes: carbohydrates, aldehydes/ketones, carbonic acids/esters, substituted phenols, furans, aliphatic hydrocarbons, substituted benzenes, and polycyclic aromatic hydrocarbons. Substance spectra were generated that showed certain conformities, especially between the insulating materials made from wood, cellulose, and meadow grass as well as hemp and jute. Comparisons of the sum of peak areas in the GC/MS‐chromatograms provided indications of the relative extent of thermal decomposition product emissions. Calculations according to (∑peak areas renewable material)/(∑peak areas polystyrene) revealed factors between 0.18 (wood, cork) and 0.028 (meadow grass). In the thermal emissions, defined hazardous substances or substance groups were frequently measured. These were included in a toxicity evaluation by which, inter alia, advantages of the natural products compared to polystyrene could be demonstrated. [ABSTRACT FROM AUTHOR]

It is a well-established fact that the quality and quantity of landfill gas (LFG) start declining after a landfill is closed to further waste intake. Conventional gas treatment and utilisation systems such as flares and gas-driven engines require a certain quality of LFG: specifically, a sufficient methane concentration. Various measures are utilised to maintain the necessary quality of LFG, including a turn-down of gas extraction rates and a shutdown of low-quality gas wells, resulting in a decline of LFG production. This, however, does not have to be the case. The low calorific value (LCV) LFG capture and treatment technology developed by e-flox and referred to in this article as 'LCV LFG System' can significantly increase the collection rate and the amount of treated methane in an old landfill. This article introduces such new treatment measures, describes gas capture calculation methodologies and presents actual results based on a medium-sized landfill in Germany. The study demonstrates, among other things, that the LCV LFG system can reduce the CO2 avoidance costs to roughly 10 €/tCO2eq. We present this new technology as a quick and straightforward measure of dealing with the climate issues related to methane emissions of old landfills. [ABSTRACT FROM AUTHOR]

Contamination of wood chip fuels with soil material, e. g. during logging operations, might result in a deterioration of fuel quality and in elevated gaseous and particulate emissions, corrosion, or slag formation during combustion in biomass boilers. In contrast, fuel upgrading by washing/screening might improve combustion behaviour. To investigate these effects, wood chips from stemwood and forest residues originating from three different forest growing regions (A to C) in Bavaria, Germany, were deliberately contaminated with mineral soils at two mixing ratios (5 %, 10 %) or were mechanically upgraded by screening or washing (only fuels from region A). Contamination was performed using three typical forest soils from Bavaria that corresponded to the selected fuel growing areas (soil A, B and C). Wood chips were tested for fuel quality according to ISO standards for solid biofuels and combusted in a 30 kW biomass boiler. Throughout the trials, fuel upgrading usually improved combustion behaviour. Total particulate matter (TPM) emissions increased for wood chips from stemwood when contaminated with soil A and C from 50 mg/m3 up to 236 mg/m3 (STC), compared to the reference fuel, while emissions for wood chips contaminated with soil B remained constant at approx. 50 mg/m3 (STC). Carbon monoxide (CO) emissions decreased for contaminated wood chips by up to 89 %. For NO X emissions, no clear effect was observed. In addition, contamination mostly increased slagging of fuels when contaminated with soil. Overall, the contamination of woody biomass had a noticeable effect on pollutant emissions and slag formation and should be avoided. • Wood chips were contaminated with mineral soil or upgraded by screening/washing. • Fuels were analyzed for physical/chemical fuel quality and combusted in a 30 kw boiler. • In contrast to contamination, fuel upgrading usually improved combustion behaviour. • TPM emissions increased for wood contaminated with soil A and C but not for soil B. • Slagging of fuels occurred when wood chips were contaminated with soil material. [ABSTRACT FROM AUTHOR]

• Compares three low-carbon technologies: battery electric vehicles, vehicles with hydrogen-based fuel cell, and vehicles with internal combustion engine based on decarbonized fuels. • Identifies, characterizes and compares the technologies' uncertainties • Distinguishes and compares five uncertainty clusters. • Outlines all three drive technologies to be affected by a similar number and quality of uncertainties. • Emphasizes importance of simultaneous advancement of all options to avoid lock-in decisions. Road transport remains to be one of Germany's main obstacles to effective greenhouse gas emissions reduction. Even though the climate ambition is clear, disagreement about the preference of alternative low-carbon drive technologies for road transport persist to this day. While uncertainty is a main reason for this disagreement it has been largely ignored in the comparison of the three main options: battery electric vehicles, vehicles with hydrogen-based fuel cell, and vehicles with internal combustion engine based on decarbonized fuels. By combining argument mapping with uncertainty analysis we identify, characterize and compare the uncertainties on Germany's energy transition of road transport. We find that all drive technologies are affected by a similar number and quality of uncertainties. Our results emphasize why any final drive technology preference is still unjustified and why all options should be advanced alongside each other to avoid lock-in decisions. [ABSTRACT FROM AUTHOR]

Bioenergy conversion technologies have been frequently described and analysed in the literature, but a comprehensive and detailed comparison between the complex individual characteristics of each technology is still lacking. Therefore, the paper contains a description of the technical, economic and environmental properties of each technology with a special focus on the German bioenergy sector. The study presents an analysis of different bioenergy applications with regard to their specifications, power/heat output range and their areas of application. Due to the fact, that biomass combustion applications are the most widespread and market proven renewable conversion technologies, a detailed analysis of decentralised, biomass-fired CHP plants is presented in the paper. The overview of the individual characteristics of different biomass conversion routes shows that biogas plants achieve high electrical efficiencies, are available with a broad range of capacities and belong to the established technologies. Although the investment costs of biogas plants are relatively high, biomass conversion with anaerobic digestion can be seen as one of the most promising option for a sustainable energy supply in Europe. [ABSTRACT FROM AUTHOR]

Miscanthus (ANDERSSON) is considered a promising perennial industrial crop for providing biomass in a growing bioeconomy. One approach to increasing the biodiversity-enhancing ecosystem services of Miscanthus is the co-cultivation of flower-rich native wild plant species (WPS), for example, the perennial WPS common tansy (Tanacetum vulgare L.) and mugwort (Artemisia vulgaris L.), as well as the biennial WPS wild teasel (Dipsacus fullonum L.) and yellow melilot (Melilotus officinalis L.). This study tested whether these selected WPS would be as suitable for combustion as Miscanthus, in this case the sterile hybrid Miscanthus x giganteus Greef et Deuter, allowing for a mixing of the biomasses. By doing so, no additional value chain (e.g. biogas production) would be necessary to economically exploit the diversification of the agricultural system for bioenergy production. Feedstock samples of Miscanthus and the four above-mentioned WPS from a field trial in southwest Germany were used to investigate the combustion characteristics as well as the higher heating value (HHV). It was found that all WPS exhibited better combustion properties than Miscanthus with respect to ash melting behavior at similar HHVs of 16.3–17.5 MJ kg−1. From an admixture of >30% WPS to the Miscanthus biomass, a significant increase in the ash melting temperature by 20% from 1000 to 1200 °C was shown. Thus, the mixture of WPS and Miscanthus could potentially improve the combustion quality, leading to reduced costs in the incineration plant operation process. However, the reduced costs of incineration should be greater than the loss in productivity due to the lower biomass yields from the WPS. This is highly dependent on the particular site conditions and the establishment success of the WPS and needs to be investigated in long-term studies. • Four types of wild plant (WP)- Miscanthus biomass blending series were investigated. • WP biomass addition improved ash melting behavior of Miscanthus biomass. • The higher heating value was not affected by WP biomass addition. • Co-cultivating Miscanthus and WPs could increase agrobiodiversity and resilience. • WPs help improve sustainability of Miscanthus utilization for energy production. [ABSTRACT FROM AUTHOR]

This article investigates greenhouse gas (GHG) emissions from commercial and industrial (C&I) waste treatment considering five sector-specific waste compositions and four different treatment scenarios in Germany. Results show that the highest share of CO2-equivalent emissions can be avoided in each of the analysed industrial sectors if solid recovered fuel (SRF) is produced for co-incineration in cement kilns. Across all industries, emissions of approximately 680 kg CO2-eq. Mg−1 C&I waste can be avoided on average under this scenario. The combustion of C&I waste in waste incineration plants without any previous mechanical treatment generates the lowest potential to avoid GHG emissions with a value of approximately 50 kg CO2-eq. Mg−1 C&I waste on average in all industries. If recyclables are sorted, this can save emissions of approximately 280 kg CO2-eq. Mg−1 C&I waste while the treatment in SRF power plants amounts to savings of approximately 210 kg CO2-eq. Mg−1 C&I waste. A comparison of the treatment scenarios of the waste from these five sectors shows that waste treatment of the craft sector leads to the lowest CO2-equivalent reduction rates of all scenarios. In contrast, the treatment of waste from catering sector leads to the highest CO2-equivalent reduction rates except for direct incineration in waste incineration plants. The sensitivity analysis of the different scenarios for this paper shows that the efficiency and the substitution factor of energy have a relevant influence on the result. Changes in the substitution factor of 10% can result in changes in emissions of approximately 55 to 75 kg CO2-eq. Mg−1 in waste incineration plants and approximately 90 kg CO2-eq. Mg−1 in the case of cement kilns. [ABSTRACT FROM AUTHOR]

Currently, in ten coal-fired power plants in Germany solid recovered fuels from mixed municipal waste and production-specific commercial waste are co-combusted and experiments have been conducted at other locations. Overall, in 2010 approximately 800 000 tonnes of these solid recovered fuels were used. In the coming years up to 2014 a slight decline in the quantity of materials used in co-combustions is expected. The co-combustion activities are in part significantly influenced by increasing power supply from renewable sources of energy and their impact on the regime of coal-fired power plants usage. Moreover, price trends of CO2 allowances, solid recovered fuels as well as imported coal also have significant influence. In addition to the usage of solid recovered fuels with biogenic content, the co-combustion of pure renewable biofuels has become more important in coal-fired power plants. The power plant operators make high demands on the quality of solid recovered fuels. As the operational experience shows, a set of problems may be posed by co-combustion. The key factors in process engineering are firing technique and corrosion. A significant ecological key factor is the emission of pollutants into the atmosphere. The results of this study derive from research made on the basis of an extensive literature search as well as a survey on power plant operators in Germany. The data from operators was updated in spring 2011. [ABSTRACT FROM AUTHOR]

Abstract: RWE Power, BASF and Linde entered into a cooperation in 2007 to adapt the CO2-scrubbing technology for application in power plants and to optimize significantly the technical and economic performance of CO2 post-combustion capture. All aspects of the capture process on the basis of new energy-efficient solvents developed by BASF and the improved plant technology by Linde are investigated in a pilot plant at RWE Power''s lignite-fired power station in Niederaussem, Germany. Some 250 measurements and an online-gas analysis system allow a detailed validation of the operational performance of the plant and a precise determination of the energy demand for the CO2 capture process. In extensive accompanying analysis programs, solvent stability and the formation of degradation products and emissions are investigated. Including commissioning, start up and extensive parameter studies, the pilot plant was in operation for more than 5000h with 30%-weight MEA as benchmark solvent from mid-2009 until January 2010. During this time, all aspects of the optimized process configuration were tested and compared with modeling results and literature data. This paper describes the performance validation approach on the basis of the results of the measurement program (specific energy demand: 3.5GJ/tCO2) and the investigation of the time-dependence of MEA degradation and organic acid formation under real power plant operating conditions (MEA loss: 0.3kg/tCO2; after 5000h of operation weight-related content of acetate: 1.8%, formate: 0.2% and oxalate: <0.1%). [Copyright &y& Elsevier]

Abstract: Ambient PM10 concentration monitoring as well as dispersion calculations were conducted to determine the influence of emissions from domestic heating on ambient PM10 concentrations in Augsburg, Germany. Based on the Augsburg emission inventory for domestic heating an average emission factor for particulate emissions from the combustion of different solid fuels (wood logs, pellets, briquettes) in different types of stoves under various combustion conditions was found to be 120 mg MJ−1 related to energy input. Hence an emission model as well as a wind field model were created for dispersion calculation of the emitted PM from wood combustion within Augsburg. The results of the dispersion calculation concurred with the ambient PM10 monitoring data measured during the heating period 2007/2008. One result found that in residential areas with a high density of stoves the observed maximum concentration value of 9 μg m−3 from wood combustion was up to 50% higher than in the city center. Ambient monitoring as well as dispersion calculation have shown a significant influence of wood combustion on ambient PM10 concentrations in Augsburg. Based on these results the impact of wood combustion in a city can be estimated. [Copyright &y& Elsevier]

Abstract: Situated in the near of Schwarze Pumpe power station southeast of Berlin, Germany, Vattenfall operates a 30 MWth pilot plant in order to investigate the Oxyfuel process. Hitachi Power Europe delivered a DST-burner (DST-Brenner®) for the indirect firing system of the plant which was installed without modifications to the pressure part of the boiler. The combustion behavior during Oxyfuel operation was investigated and optimal burner settings for different operation points were established. The results show that the burner can be operated in a wide range of oxygen concentrations in the oxidant gas flow. The burner is characterized by low emissions of carbon monoxide and nitrogen oxides. The high flame stability was found to be unaffected by operational influences such as fluctuations in the coal mass flow, coal quality or soot blowing. Due to the high flame stability the change-over from air blown to Oxyfuel combustion can be realized very easily and is automated. During Oxyfuel operation measurements of temperatures and flue gas species in the flame were performed. The measurement values were compared with the values of the combustion modeling by computational fluid dynamics. The good agreement between both measurement and modeling shows the suitability of the applied models to predict the combustion behavior under Oxyfuel conditions. [Copyright &y& Elsevier]

The dominant sink of atmospheric molecular hydrogen (H2) is its enzymatic destruction in soils. Quantitative estimates of the global sink strength, as derived from bottom-up process studies, are, however, still associated to large uncertainties. Here we present an alternative way to estimate atmosphere-to-soil flux densities, respectively deposition velocities of H2, based on atmospheric H2 and 222Rn observations in the boundary layer. Two and a half years of continuous measurements from a polluted site in the Rhine-Neckar area have been evaluated and night-time flux densities were calculated for situations of strong nocturnal boundary layer inversions using the Radon-Tracer Method. The influences from local anthropogenic combustion sources could be detected and successfully separated by parallel measurements of carbon monoxide. Inferred daily uptake fluxes in the Heidelberg catchment area range from 0.5 to 3 × 10−8 g H2 m−2 s−1 with a mean value of (1.28 ± 0.31) × 10−8 g H2 m−2 s−1. Uptake rates are about 25% larger during summer than during winter, when soil moisture is high, and diffusive transport of H2 into the soil is inhibited. The mean deposition velocity is 3.0 ± 0.7 × 10−2 cm s−1, which is very well in line with direct measurements on similar soil types in Europe and elsewhere. [ABSTRACT FROM AUTHOR]

The hydrogen-to-carbon monoxide (H2/CO) emission ratio of anthropogenic combustion sources was determined from more than two years of quasi-continuous atmospheric observations in Heidelberg (49°24′ N, 8°42′ E), located in the polluted Rhein-Neckar region. Evaluating concurrent mixing ratio changes of H2 and CO during morning rush hours yielded mean molar H2/CO ratios of 0.40 ± 0.06, while respective results inferred from synoptic pollution events gave a mean value of 0.31 ± 0.05 mole H2/mole CO. After correction for the influence of the H2 soil sink on the measured ratios, mean values of 0.46 ± 0.07 resp. 0.48 ± 0.07 mole H2/mole CO were obtained, which are in excellent agreement with direct source studies of traffic emissions in the Heidelberg/Mannheim region (0.448 ± 0.003 mole H2/mole CO). Including results from other European studies, our best estimate of the mean H2/CO emission ratio from anthropogenic combustion sources (mainly traffic) ranges from 0.45 to 0.48 mole H2/mole CO, which is about 20% smaller than the value of 0.59 mole H2/mole CO which is frequently used as the basis to calculate global H2 emissions from anthropogenic combustion sources. [ABSTRACT FROM AUTHOR]

Abstract: In 2007 RWE Power, BASF and Linde entered into a cooperation to develop an optimized post combustion capture technology for power plants. In mid-2009 a CO2 capture pilot plant will be commissioned at RWE Power’s lignite-fired power plant at Niederaussem, Germany. The pilot plant comprises all significant components of a large post combustion capture plant but on a smaller scale. Some capture process optimization measures are implemented that should increase the overall efficiency and reduce the costs of a commercial capture plant. The design of the pilot plant - engineering, procurement and construction by Linde - allows testing the performance and stability of optimized CO2 solvents, which BASF is currently developing. On the basis of an elaborated solvent selection methodology (pre-selection, screening, etc.) comprehensive experiments are carried out in order to examine solvent performance, and some measures for the optimization of the process configuration are developed. The 18-month pilot plant testing programme will allow the performance of the optimized solvent and the process to be evaluated. [Copyright &y& Elsevier]

The emission from industries and the mobility sector is under strong legal regulations in many countries worldwide. In Germany, the amendment to the 17th BlmSchV (Federal pollution control ordinance), which has been in force for waste incineration plants since 2013, has given rise to a new limit for nitrogen oxides of 150 mg/m3 as the daily mean level from 2019 on. A similar focus is on biomass-fired plants. According to the MCP (medium combustion plant) guideline of the EU, as a consequence, existing plants are required to either increase their consumption of ammonia water for nitrogen oxide reduction (SNCR process) or back fit SCR catalysts as secondary measures, which is a costly procedure. This paper presents a novel two-stage process in which an oscillating supply of secondary air allows nitrogen oxides to be reduced by approx. 50% at a good burnout level, which may obviate the need for secondary measures. Besides experimental investigations in a fixed bed reactor, CFD simulations confirm a high potential for reduction of nitrogen oxides. Together with the company POLZENITH, this process is under development for scale-up in a biomass incineration plant as a next step. [ABSTRACT FROM AUTHOR]

A technique was developed to measure stable carbon isotope ratios (13C/12C) of light volatile organic compounds (VOCs) such as isoprene, methacrolein (MACR) and methyl vinyl ketone (MVK) using gas chromatography combustion isotope ratio mass spectrometry (GCC-IRMS). An automated sampling and cryofocussing system allowed for the extraction of VOCs from air samples of up to 140 L of air collected over 3 h, and the subsequent 13C/12C analysis of the VOCs by GCC-IRMS. Chromatography using selective transfer between two columns was used to improve the separation for selected compounds, increasing peak resolution and attaining less noisy baselines. Still, some target compounds could not be completely separated from co-eluting peaks. To reduce the bias of isotope ratio determinations, which can result from incomplete peak resolution, a peak-fitting procedure has been developed. In cases of overlapping peaks or substantial baseline drift, this peak fitting allows more accurate determination of isotope ratios than conventional integration schemes. Comparisons between off-line IRMS measurements and a peak-evaluation procedure using a prepared VOC gas-phase standard show that isotope ratios derived from large (>1 ng of carbon per peak) and well-resolved peaks have a reproducibility of ±0.3‰. With smaller masses in the range of 0.1–1 ng of carbon, reproducibility decreased to ±(0.5–0.8)‰. For a 140 L sample of air, such small masses of carbon correspond to mixing ratios in the low pptV range. The developed measurement technique was applied to a small set of ambient air samples taken during hot, sunny periods from late May to early August, 2005, at Forschungszentrum Jülich, Germany, a semi-rural area. The range of δ13C values determined for isoprene, benzene, and toluene are consistent with those reported in the literature. GCC-IRMS results of δ13C for ambient samples of isoprene, MACR, and MVK, measured at mixing ratios of 15–280 pptV, are presented and discussed. [ABSTRACT FROM AUTHOR]

Abstract: Significant differences exist in the flue gas composition in hot recycle Oxyfuel conditions as e.g. the high CO2 partial pressure (>90vol%, dry), the very high SO2 concentration and the high water content (approx. 30vol%). Therefore certain design and operation criteria have to be observed for the flue gas desulphurization with forced oxidation under Oxyfuel combustion conditions. Several performance tests have been executed at the 30MWth Oxyfuel pilot plant in Schwarze Pumpe to evaluate the main performance parameters and to assess the influence of the major operation parameters. The results show that there are no fundamental problems for the operation of the flue gas desulphurization unit under Oxyfuel combustion conditions. High removal rates could be reached and no negative impact of the high CO2 partial pressure was observed under the tested operating conditions. No major differences in the gypsum quality have been observed between air firing and Oxyfuel conditions. [Copyright &y& Elsevier]