Papers by Edward J Anthony
Current Opinion in Green and Sustainable Chemistry
Renewable and Sustainable Energy Reviews, 2020
Carbon dioxide (CO2) is the major contributor to greenhouse gas (GHG) emissions and the main driv... more Carbon dioxide (CO2) is the major contributor to greenhouse gas (GHG) emissions and the main driver of climate change. Currently, CO2 utilization is increasingly attracting interest in processes like enhanced oil recovery and coal bed methane and it has the potential to be
Chemical Engineering Journal, 2019
Alkali metal nitrate-/nitrite-promoted MgO sorbents are promising candidates for intermediate-tem... more Alkali metal nitrate-/nitrite-promoted MgO sorbents are promising candidates for intermediate-temperature (200-500 °C) CO 2 capture. However, the structure-performance relationship and kinetic characteristics of NaNO 2-promoted MgO remain unclear. Here the effects of physical-chemical properties on the CO 2 sorption performance of NaNO 2-promoted MgO and the sorption kinetics were comprehensively studied to elucidate the detailed role of NaNO 2. Samples were characterized by X-ray diffraction, scanning electron microscopy, N 2 adsorption, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The sorption kinetics were obtained by isothermal thermogravimetry and elucidated using a double exponential model. Compared with pure MgO and NaNO 3-promoted MgO, NaNO 2-modified MgO had a lower initial sorption temperature and a unique bimodal sorption characteristic. Characterizations results revealed that such bimodal sorption
Chemical Engineering Journal, 2018
A series of mesoporous MgO samples with different morphologies were synthesized through a simple ... more A series of mesoporous MgO samples with different morphologies were synthesized through a simple hydrothermal treatment and NaNO 3 /NaNO 2 were used as promoters to enhance CO 2 capture capacity at an intermediate temperature range (200-400 °C). The effects of hydrothermal solution pH and content of promoters were examined to determine the optimal synthesis conditions. The influence of operational temperatures, CO 2 partial pressure, and performance over repeated cycles was investigated and the reaction mechanism was discussed. The mesoporous MgO promoted by NaNO 3 /NaNO 2 exhibited a CO 2 capture capacity as high as 19.8 mmol•g-1 at 350 °C in the presence of 0.85 bar of CO 2 within only 50 min. A "three-stage" reaction process was proposed based on a detailed sorption kinetics study, namely Stage I: initiating interactions between CO 2 and exposed MgO; Stage II: generation and accumulation of Mg 2+ and CO 3 2-; and Stage III: fast carbonation. Gradual deterioration of sorbents was found over the first 5 cycles followed by stable regenerability in the 5-15 th cycles. A kinetic study of the 15 th cycle suggests that the deactivation of sorbents inhibited the accumulation of Mg 2+ and CO 3 2in Stage II and suppressed the carbonation in Stage III. A range of characterizations were undertaken revealing the morphology and structure of both fresh and regenerated sorbents. The results confirmed that, other than the sintering effect due to phase transition, the transformation of MgO skeleton is also an important contributor to the gradual deactivation of the sorbents over the first 5 cycles. More severe sintering effect under harsh decarbonation conditions suppressed the stability of the sorbents over cycles.
Journal of Materials Chemistry A, 2019
The preparation of CaO/CuO composites with high performance is essential for combined Ca–Cu loopi... more The preparation of CaO/CuO composites with high performance is essential for combined Ca–Cu looping process, where the exothermic reduction of CuO with methane is used in situ to calcine CaCO3.
Progress in Clean Energy, Volume 2, 2015
Oxyfuel combustion is one of the major carbon capture technologies, and a very promising techniqu... more Oxyfuel combustion is one of the major carbon capture technologies, and a very promising technique to facilitate CO 2 Capture and Sequestration (CCS) for new and existing coal/biomass-fired power plants. In this research experimental and simulation oxy-combustion trials are carried out at Cranfield University by co-firing mixtures of pulverised coal and biomass using a 100kW retrofitted oxy-combustor. The parent fuels are coal (Daw Mill) and biomass cereal co-product (CCP) and experimental work was done for 100% coal (w/w), 100% biomass (w/w) and a blend of coal 50% (w/w) and biomass 50% (w/w). The recirculation flue gas (RFG) rate was set to be of 52% of the total flue gas. The maximum percentage of CO 2 observed was 56.7% wet-based (73.6% on a dry basis) when 100% Daw Mill coal was fired. Major and minor emissions species and gas temperature profiles were obtained and analysed for different fuel mixtures. A drop in the maximum temperature of more than 200K was observed when changing the fuel from 100% Daw Mill coal to 100% cereal co-product biomass. Deposits formed on the ash deposition probes were also collected and analysed using the Environmental Scanning Electron Microscopy (ESEM) with Energy Dispersive X-ray (EDX) technique. The high sulphur, potassium and chlorine contents detected in the ash generated using 100% cereal co-product biomass are expected to increase the corrosion potential of these deposits. In addition, a rate-based simulation model has been developed using Aspen Plus® and validated by comparison with the experimental results. It is concluded that the model provides an adequate prediction for the gas composition of the flue gas. INTRODUCTION Oxy-fuel combustion is one of the main options for the capture of CO 2 from fossil fuel-fired power generation. Oxyfuel combustion has several characteristics which make it a very attractive technology to implement in both existing air-firing and new power plants. These include, generation of a stream of flue gas with a high percentage of CO 2 which is easy to be captured, reduction in the size of the flue gas conditioning equipment, no additional space required for the post combustion capture equipment and also reduced environmental impacts compared with other carbon capture technologies (Corsten et al., 2013). The main disadvantage of oxy-fuel combustion technology is the efficiency loss and elevated cost associated with generating high-purity O 2 by cryogenic separation. Nonetheless, oxy-firing remains an extremely promising option as it requires minimal modification of existing coal-fired plants, and for coal-firing at least it can already be considered to be near commercial technology. This is, however, not the case for co-firing with biomass. Such studies that have been done on co-firing of coal and biomass (Arias et al., 2008 ; Toftegaard et al., 2010) have noted that the ignition temperature decreases as the proportion of biomass in the fuel increases. It is found that the fuel burnout improves when oxy-firing blends of coal and biomass (
Energy conversion and management, 2018
A probabilistic modelling approach was developed and applied to investigate the energy and enviro... more A probabilistic modelling approach was developed and applied to investigate the energy and environmental performance of an innovative sanitation system, the "Nano-membrane Toilet" (NMT). The system treats human excreta via an advanced energy and water recovery island with the aim of addressing current and future sanitation demands. Due to the complex design and inherent characteristics of the system's input material, there are a number of stochastic variables which may significantly affect the system's performance. The non-intrusive probabilistic approach adopted in this study combines a finite number of deterministic thermodynamic process simulations with an artificial neural network (ANN) approximation model and Monte Carlo simulations (MCS) to assess the effect of system uncertainties on the predicted performance of the NMT system. The joint probability distributions of the process performance indicators suggest a Stirling Engine (SE) power output in the range o...
Fuel, 2017
The use of biomass-templating materials with a cheap production method as an enhanced sorbent for... more The use of biomass-templating materials with a cheap production method as an enhanced sorbent for CO2 uptake has been proposed recently. However, the attrition and fragmentation behaviour of this type of material, which is a vital parameter for calcium looping sorbents, has not yet been investigated in detail. In this work the attrition and fragmentation behaviour of biomass-templated sorbents is investigated. Three types of materials were prepared using a mechanical pelletiser: 1. lime and cement (LC); 2. lime and flour (LF); and 3. lime, cement and flour (LCF). These samples were heat treated in a pressurised heated strip reactor (PHSR) and in a bubbling fluidised bed (BFB) and changes in particle size distribution were measured to assess fragmentation. Results indicated that the addition of biomass enhances the propensity to undergo fragmentation. Upon heat treatment in the PHSR the particle size of LC was not modified significantly; on the contrary the mean particle diameter of LF decreased from 520 µm to 116 µm and that of LCF from 524 µm to 290 µm. Fragmentation tests in the BFB confirmed the trend: 67% of the particles of LF fragmented, against 53% of LCF and 18% of LC samples. The addition of biomass to the LC samples partially counteracts this performance degradation with respect to attrition. However, calcium aluminate pellets (LC) showed the lowest rate of fragmentation amongst all of the samples tested.
International Journal of Greenhouse Gas Control, 2015
Abstract Carbon capture and storage (CCS) is expected to provide a cost-effective means of CO 2 e... more Abstract Carbon capture and storage (CCS) is expected to provide a cost-effective means of CO 2 emission reduction from the power sector. Amine scrubbing, which is the closest CCS technology to the market, is a suitable option for coal-fired power plants in retrofit scenarios. However, the energy requirement for solvent regeneration in chemical absorption CO 2 capture processes causes a substantial reduction in the power plant efficiency and power output. Therefore, novel technologies with lower efficiency penalties need to be developed. One promising option is calcium looping (CaL) which is based on the reversible carbonation/calcination reaction of calcium-based sorbent that takes place at high temperature. For the purpose of this study, the CaL process was model was developed and then linked to a high-fidelity model of a reference 580 MW el supercritical coal-fired power plant. A secondary steam cycle was also modelled for recovery of high-grade heat from the CaL process. The results of the process analysis revealed that the efficiency penalty imposed in the CaL plant retrofit scenario was 6.7–7.9% points. Such performance compares favourably to the monoethanolamine and chilled ammonia scrubbing retrofit scenarios, which have efficiency penalties of 9.5% and 9.0%, respectively. Moreover, the retrofit of the CaL process was found to be less complex, and would result in two times higher net power output compared to the chemical solvent scrubbing scenarios. This is an important advantage of the CaL plant over the more mature CO 2 capture technologies, especially for the power plant operators who are looking to increase the system capacity to meet the increasing electricity demand and, at the same time, to reduce the CO 2 emissions.
Energy & Environmental Science, 2015
A nearly complete decarbonisation of the power sector is essential to meet the European Union tar... more A nearly complete decarbonisation of the power sector is essential to meet the European Union target for greenhouse gas emissions reduction.
Powder Technology, 2011
Emission of sulphur dioxide (SO 2) from combustion of fossil fuel is an important environmental i... more Emission of sulphur dioxide (SO 2) from combustion of fossil fuel is an important environmental issue. Circulating fluidized bed combustion (CFBC) technology can use limestone sorbent to achieve in situ SO 2 emissions control. This paper presents the chemical and physical analysis results of two fly ash samples derived from a 165 MWe CFBC boiler burning two different fuels with addition of limestone, as they pertain to sulphation behavior. One of the samples in this study was produced from combustion of a bituminous coal with high iron content, the other from firing of blended coal and petroleum coke fuel. The physical examination was conducted by scanning electron microscope (SEM) coupled with an energy dispersive X-ray (EDX) system for analysis of the surface structure or morphology of the sample, as well as the calcium and sulphur distribution. Some large particles derived from high-iron-content fuel were covered by dense iron shells; however, in general such a dense rim was found to not significantly impede the overall desulphurization performance in FBC in terms of the limestone utilization. The large particles (~100 μm in diameter) in both samples typically consisted of a CaSO 4 shell and an almost pure CaO core; however, numerous small particles of diameters of 10-20 μm consisted predominantly of CaO without sulphate shells. In particular, the emphasis of this investigation has been focused on the remaining capacity of the fly ash for reaction with sulphur dioxide and to clarify the effects of iron, both samples have been doped with additional iron content, and their sulphation behavior examined, and while both experienced a small reduction in sulphation capacity, the fly ash with the initial low iron content experienced the lowest reduction of sulphation capacity after doping, which is not supportive of the idea that iron has an important effect on sorbent capacity.
Journal of Energy Resources Technology, 2006
Disposal of fluidized bed combustion (FBC) solid residues currently represents one of the major i... more Disposal of fluidized bed combustion (FBC) solid residues currently represents one of the major issues in FBC design and operation, and contributes significantly to its operating cost. This issue has triggered research activities on the enhancement of sorbent utilization for in situ sulfur removal. The present study addresses the effectiveness of the reactivation by liquid water hydration of FB spent sorbents. Two materials are considered in the study, namely the bottom ash from the operation of a full-scale utility FB boiler and the raw commercial limestone used in the same boiler. Hydration-reactivation tests were carried out at temperatures of 40°C and 80°C and for curing times ranging from 15minutes to 2d, depending on the sample. The influence of hydration conditions on the enhancement of sulfur utilization has been assessed. A combination of methods has been used to characterize the properties of liquid water-hydrated materials.
Industrial & Engineering Chemistry Research, 2005
... Jinsheng Wang,* Yinghai Wu, and Edward J. Anthony. CANMET Energy Technology ... 13) Laursen, ... more ... Jinsheng Wang,* Yinghai Wu, and Edward J. Anthony. CANMET Energy Technology ... 13) Laursen, K.; Mehrani, P.; Lim, CJ; Grace, JR Steam reactivation of partially utilized limestone sulfur sorbents. Environ. Eng. Sci.2003, 20, 11. ...
Fuel, 2005
Hydration studies on CFBC ashes have shown that the acetone technique to prevent hydration in sto... more Hydration studies on CFBC ashes have shown that the acetone technique to prevent hydration in stored samples is relatively effective, only allowing some slight degree of hydration over days, in the presence of excess water. In the presence of large excesses of water sufficient to control temperature increases, the degree of bulk mixing has no effect on the degree of hydration, which is shown to be relatively slow at ambient conditions, taking hours to complete. Finally, the effect of salt addition on hydration has been shown to negligible at the low levels typical of wastewater, but there may be effects at ion concentrations typical of seawater. This work suggests that experience gained from lime hydration should be applied with caution to studies on hydration of CFBC ashes.
Chemical Engineering Communications, 2007
A simple model is proposed for sulphation of CaO-based sorbents in fluidized bed combustion. The ... more A simple model is proposed for sulphation of CaO-based sorbents in fluidized bed combustion. The model focuses on the sintering effect of CaSO4 product on the sorbent particles. The resultant equation is validated with experimental data and is seen to describe the time dependence of the sulphation well. It is also shown that for short sulphation times the equation becomes equivalent to that of an existing model but gives a better description of the sulphation behavior over a long sulphation period.
Fuel, 2014
h i g h l i g h t s The pressurized CO 2 and SO 2 capture ability of Ca-sorbents was investigated... more h i g h l i g h t s The pressurized CO 2 and SO 2 capture ability of Ca-sorbents was investigated. Pressure increment resulted in reduced CO 2 capture and increased SO 2 retention. Sulphation via unreacted core mode utilized higher proportions of calcium. Changing CO 2 p. pressure slightly influenced SO 2 retention at elevated pressure. Increased total and SO 2 p. pressure strongly deteriorates reversibility.
The Canadian Journal of Chemical Engineering, 1999
Page 1. The NO and N 0 Formation Mechanism under Circulating Flui ii ized Bed Combustor Condition... more Page 1. The NO and N 0 Formation Mechanism under Circulating Flui ii ized Bed Combustor Conditions: from the Single Particle to the Pilot-Scale FRANZ WINTER'*, GERHARD LOFFLER', CHRISTIAN WARTHA', HERMANN ...
Significant research has been carried out to investigate the carbonation of CaO as a potential me... more Significant research has been carried out to investigate the carbonation of CaO as a potential method for CO2 capture and sequestration. Up to date, the majority of this work has been related with CO2 removal from combustion flue gases with little attention focused on the carbonation reaction kinetics under gasification syngas conditions. The intrinsic rate constants of the CaO-CCh reaction was studied via a grain model for two naturally occurring calcium oxide based sorbents using a thermogravimetric analyzer. An apparent kinetic model was used to cover both the chemical reaction and diffusion rate control regimes to enable the development of a single phase, plug flow, moving bed carbonator reactor model. Over temperatures ranging from 580-700°C, it was observed that the presence of CO and H2 during carbonation caused a significant increase in the initial rate of carbonation which has been attributed to the CaO surface sites catalyzing the water-gas shift reaction increasing the lo...
Fuel and Energy Abstracts
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Papers by Edward J Anthony