Dr Florin is a Research Director at the Institute for Sustainable Futures (ISF), University of Technology Sydney.
He manages the Resource Futures research group and directs and undertakes collaborative research projects with industry and government partners on resource conservation, recovery and recycling. His research involves policy options analysis, technology and infrastructure assessment, and stakeholder engagement to improve policy relevance, resource stewardship and supply chain sustainability.
Recently, he has advised the NSW Government on circular economy policy and led a major research project for the Australian Packaging Covenant Organisation that traced material flows through the waste management system and assessed resource recovery opportunities and pathways towards a circular economy for packaging. Dr Florin has also partnered with Queensland and ACT governments, as well as the Australian Battery Recycling Initiative and the Battery Stewardship Council, on projects supporting the development of product stewardship for clean energy systems.
Nick was the Deputy Leader of the Wealth from Waste Research Cluster at the Institute for Sustainable Futures that is focused on identifying pathways for creating wealth from waste containing metals, including e-waste. The $9m three year collaboration (2014-2016) partners with researchers at The University of Queensland, Monash, Swinburne and Yale.
Can supervise: YES
Get in touch for details on PhD and Master’s project opportunities:
- Circular economy and product stewardship
- Resource conservation, recovery and recycling
- Supply chain sustainability
- Carbon mitigation
Boot-Handford, M, Virmond, E, Florin, N, Kandiyoti, R & Fennell, P 2018, 'Simple pyrolysis experiments for the preliminary assessment of biomass feedstocks and low-cost tar cracking catalysts for downdraft gasification applications', Biomass and Bioenergy, vol. 108, pp. 398-414.View/Download from: UTS OPUS or Publisher's site
The pyrolysis behaviour of beech wood, two rice husk variants from Brazil (BRH) and Thailand (TRH) and a solid waste water treatment residue from textile manufacture (TIR) were investigated using a lab-scale, 2-stage fixed-bed reactor at 773 K. Char yields increased and volatile yields decreased with increasing ash content. The TRH released 40% less tar than the BRH which was attributed to the substantially higher potassium content of the Thai species. The combustion reactivity of the TRH char in air at 773 K was similar to the BW char and almost double the reactivity of the BRH and TIR chars. The BW and TRH chars had a greater volume of macropores indicating that char combustion occurs predominantly through the growth and extension of the macroporous pore network. A different trend was observed for the char gasification reactivity with CO2 at 1173 K. The Ca and Mg content of the chars were found to have a more important catalytic role in the char gasification reactions with CO2.
The effect of exposing volatile products from beech wood pyrolysis to elevated temperatures (973–1173 K) and sand beds containing calcined limestone or dolomite in a simulated downdraft gasification environment was also investigated. Tar yields decreased after exposure to elevated temperature and calcined limestone or dolomite. Tar cracking favoured the production of CO. CO yields were between 22 and 23 wt% at 1173 K. Calcined dolomite was slightly more effective at cracking tar than calcined limestone, eliminating 98 wt% of the tar at 1173 K.
Dominish, E, Retamal, M, Sharpe, S, Lane, R, Rhamdhani, MA, Corder, G, Giurco, D & Florin, N 2018, '"Slowing" and "narrowing" the flow of metals for consumer goods: Evaluating opportunities and barriers', Sustainability (Switzerland), vol. 10, no. 4.View/Download from: UTS OPUS or Publisher's site
© 2018 by the authors. Metal resources are essential materials for many consumer products, including vehicles and a wide array of electrical and electronic goods. These metal resources often cause adverse social and environmental impacts from their extraction, supply and disposal, and it is therefore important to increase the sustainability of their production and use. A broad range of strategies and actions to improve the sustainability of resources are increasingly being discussed within the evolving concept of the circular economy. This paper uses this lens to evaluate the opportunities and barriers to improve the sustainability of metals in consumer products in Australia, with a focus on strategies that "slow" and "narrow" material flow loops. We have drawn on Allwood's characterisation of material efficiency strategies, as they have the potential to reduce the total demand for metals. These strategies target the distribution, sale, and use of products, which have received less research attention compared to the sustainability of mining, production, and recycling, yet it is vitally important for changing patterns of consumption in a circular economy. Specifically, we have considered the strategies of product longevity (life extension, intensity of use, repair, and resale), remanufacturing, component reuse, and using less material for the same product or service (digitisation, servicisation, and light-weighting). Within the Australian context, this paper identifies the strategies that have the greatest opportunity to increase material efficiency for metal-containing products (such as mobility, household appliances, and personal electronics), by evaluating current implementation of these strategies and identifying the material, economic, and social barriers to and opportunities for expanding these strategies. We find that many of these strategies have been successfully implemented for mobility, while applying these strategies to personal electronics remains the...
Vuppaladadiyam, AK, Yao, JG, Florin, N, George, A, Wang, X, Labeeuw, L, Jiang, Y, Davis, RW, Abbas, A, Ralph, P, Fennell, PS & Zhao, M 2018, 'Impact of Flue Gas Compounds on Microalgae and Mechanisms for Carbon Assimilation and Utilization.', ChemSusChem, vol. 11, no. 2, pp. 334-355.View/Download from: UTS OPUS or Publisher's site
To shift the world to a more sustainable future, it is necessary to phase out the use of fossil fuels and focus on the development of low-carbon alternatives. However, this transition has been slow, so there is still a large dependence on fossil-derived power, and therefore, carbon dioxide is released continuously. Owing to the potential for assimilating and utilizing carbon dioxide to generate carbon-neutral products, such as biodiesel, the application of microalgae technology to capture CO2 from flue gases has gained significant attention over the past decade. Microalgae offer a more sustainable source of biomass, which can be converted into energy, over conventional fuel crops because they grow more quickly and do not adversely affect the food supply. This review focuses on the technical feasibility of combined carbon fixation and microalgae cultivation for carbon reuse. A range of different carbon metabolisms and the impact of flue gas compounds on microalgae are appraised. Fixation of flue gas carbon dioxide is dependent on the selected microalgae strain and on flue gas compounds/concentrations. Additionally, current pilot-scale demonstrations of microalgae technology for carbon dioxide capture are assessed and its future prospects are discussed. Practical implementation of this technology at an industrial scale still requires significant research, which necessitates multidisciplinary research and development to demonstrate its viability for carbon dioxide capture from flue gases at the commercial level.
Hills, T, Florin, N & Fennell, P 2016, 'Decarbonising the cement sector: A bottom-up model for optimising carbon capture application in the UK', Journal of Cleaner Production, vol. 139, pp. 1351-1361.View/Download from: Publisher's site
Boot-Handford, ME, Florin, N & Fennell, PS 2016, 'Investigations into the effects of volatile biomass tar on the performance of Fe-based CLC oxygen carrier materials', Environmental Research Letters, vol. 11, no. 11.View/Download from: UTS OPUS or Publisher's site
© 2016 IOP Publishing Ltd. In this study we present findings from investigations into interactions between biomass tar and two iron based oxygen carrier materials (OCMs) designed for chemical-looping applications: a 100% Fe2O3 (100Fe) OCM and a 60 wt% Fe2O3/40 wt% Al2O3 (60Fe40Al) OCM. A novel 6 kWe two-stage, fixed-bed reactor was designed and constructed to simulate a chemical-looping combustion (CLC) process with ex situ gasification of biomass. Beech wood was pyrolysed in the first stage of the reactor at 773 K to produce a tar-containing fuel gas that was used to reduce the OCM loaded into the 2nd stage at 973 K. The presence of either OCM was found to significantly reduce the amount of biomass tars exiting the reactor by up to 71 wt% compared with analogous experiments in which the biomass tar compounds were exposed to an inert bed of sand. The tar cracking effect of the 60Fe40Al OCM was slightly greater than the 100Fe OCM although the reduction in the tar yield was roughly equivalent to the increase in carbon deposition observed for the 60Fe40Al OCM compared with the 100Fe OCM. In both cases, the tar cracking effect of the OCMs appeared to be independent of the oxidation state in which the OCM was exposed to the volatile biomass pyrolysis products (i.e. Fe2O3 or Fe3O4). Exposing the pyrolysis vapours to the OCMs in their oxidised (Fe2O3) form favoured the production of CO2. The production of CO was favoured when the OCMs were in their reduced (Fe3O4) form. Carbon deposition was removed in the subsequent oxidation phase with no obvious deleterious effects on the reactivity in subsequent CLC cycles with reduction by 3 mol% CO.
González, B, Blamey, J, Al-Jeboori, MJ, Florin, NH, Clough, PT & Fennell, PS 2016, 'Additive effects of steam addition and HBr doping for CaO-based sorbents for CO2 capture', Chemical Engineering and Processing: Process Intensification, vol. 103, pp. 21-26.View/Download from: Publisher's site
Calcium looping is a developing CO2 capture and storage technology that employs the reversible carbonation of CaO (potentially derived from natural limestone). The CO2 uptake potential of CaO particles reduces upon repeated reaction, largely through loss of reactive surface area and densification of particles. Doping of particles has previously been found to reduce the rate of decay of CO2 uptake, as has the introduction of steam into calcination and carbonation stages of the reaction. Here, the synergistic effects of steam and doping, using an HBr solution, of 5 natural limestones have been investigated. The enhancement to the CO2 uptake was found to be additive, with CO2 uptake after 13 cycles found to be up to 3 times higher for HBr-doped limestones subjected to cycles of carbonation and calcination in the presence of 10% steam, in comparison to natural limestone cycled in the absence of steam. A qualitative discussion of kinetic data is also presented.
Hills, T, Leeson, D, Florin, N & Fennell, P 2016, 'Carbon Capture in the Cement Industry: Technologies, Progress, and Retrofitting', Environ. Sci. Technol., vol. 50, no. 1, pp. 368-377.View/Download from: UTS OPUS or Publisher's site
Several different carbon-capture technologies have been proposed for use in the cement industry. This paper reviews their attributes, the progress that has been made toward their commercialization, and the major challenges facing their retrofitting to existing cement plants. A technology readiness level (TRL) scale for carbon capture in the cement industry is developed. For application at cement plants, partial oxy-fuel combustion, amine scrubbing, and calcium looping are the most developed (TRL 6 being the pilot system demonstrated in relevant environment), followed by direct capture (TRL 4–5 being the component and system validation at lab-scale in a relevant environment) and full oxy-fuel combustion (TRL 4 being the component and system validation at lab-scale in a lab environment). Our review suggests that advancing to TRL 7 (demonstration in plant environment) seems to be a challenge for the industry, representing a major step up from TRL 6. The important attributes that a cement plant must have to be 'carbon-capture ready' for each capture technology selection is evaluated. Common requirements are space around the preheater and precalciner section, access to CO2 transport infrastructure, and a retrofittable preheater tower. Evidence from the electricity generation sector suggests that carbon capture readiness is not always cost-effective. The similar durations of cement-plant renovation and capture-plant construction suggests that synchronizing these two actions may save considerable time and money.
Khorshidi, Z, Florin, N, Ho, M & Wiley, D 2016, 'Techno-economic evaluation of co-firing biomass gas with natural gas in existing NGCC plants with and without CO2 capture', International Journal of Greenhouse Gas Control, vol. 40, pp. 343-363.View/Download from: UTS OPUS or Publisher's site
Natural gas combined cycle (NGCC) power plants have emission intensities a half to a third that of current coal-fired power plants. To meet more stringent emission targets, it is essential to reduce the emissions of these plants to an even lower level. Co-firing gasified biomass with natural gas (NG) reduces the plant emissions while allowing continued use of existing assets. If CO2 capture and storage are also applied, negative emissions may result which could provide additional CO2 credits to reduce the overall cost of decarbonising electricity generation. This paper investigates the impact of biomass gas quantity and quality on the performance and economics of a 547 MWe NGCC plant retrofitted with biomass gas co-firing. The analysis considers co-firing with and without CO2 capture. Three co-firing levels (5%, 20%, 40%) and three biomass gasification technologies (atmospheric air-blown gasification, pressurized oxygen-blown gasification and atmospheric indirectly heated gasification) are evaluated. Compared to the baseline NGCC power plant, at low co-firing levels, the type of gasification technology does not significantly affect the overall thermal efficiency, CO2 emission intensity or cost of electricity (COE). However, at higher levels of co-firing, the overall thermal efficiency increases by up to 2.5% LHV for the atmospheric air-blown gasifier but decreases by about 0.4% LHV for the pressurized oxygen-blown gasification and 2.5% for atmospheric indirectly heated gasification technologies. The CO2 emission intensity also changes by up to 0.16–0.18 t/MWh at co-firing levels of 40% for all three gasification technologies, while the COE increases by 0.12–0.18 $/MWh. The analysis also shows that the increase in the fuel flow rate is more significant for BGs with lower heating values. The increase in the fuel flow rate can increase the topping cycle efficiency but requires more modifications to the gas turbine. Thus, co-firing BGs with lower heating value might ...
Hills, T, Gordon, F, Florin, N & Fennell, P 2015, 'Statistical analysis of the carbonation rate of concrete', Cement and Concrete Research, vol. 72, pp. 98-107.View/Download from: UTS OPUS or Publisher's site
The carbonation rate of concrete has implications for the lifecycle carbon emissions of concrete. This paper describes the reported effect of several variables on the rate of concrete carbonation and collates a data set of measurements published in the literature. Many studies producing predictive models for the carbonation rate constant, K, use only small data sets. 1999 measurements of carbonation depth as a function of time and other variables were collected for analysis. Models in the form ln (K) = a + bI1 + cI2 + … have been produced by which the rate of carbonation can be predicted. Hierarchical Models were used to combine different authors' data and introduces a new explanatory variable called 'origin', which indicates whether the concrete was taken from a working structure or cast specifically for experiments. Two models of the carbonation rate using concrete properties have been produced, allowing prediction of K over a range of conditions and compositions.
Napp, TA, Gambhir, A, Hills, TP, Florin, N & Fennell, PS 2014, 'A review of the technologies, economies and policy instruments for decarbonising energy intensive manufacturing industries', Renewable and Sustainable Energy Reviews, vol. 30, pp. 616-640.View/Download from: UTS OPUS or Publisher's site
Industrial processes account for one-third of global energy demand. The iron and steel, cement and refining sectors are particularly energy-intensive, together making up over 30% of total industrial energy consumption and producing millions of tonnes of CO2 per year. The aim of this paper is to provide a comprehensive overview of the technologies for reducing emissions from industrial processes by collating information from a wide range of sources. The paper begins with a summary of energy consumption and emissions in the industrial sector. This is followed by a detailed description of process improvements in the three sectors mentioned above, as well as cross-cutting technologies that are relevant to many industries. Lastly, a discussion of the effectiveness of government policies to facilitate the adoption of those technologies is presented. Whilst there has been significant improvement in energy efficiency in recent years, cost-effective energy efficient options still remain. Key energy efficiency measures include upgrading process units to Best Practice, installing new electrical equipment such as pumps and even replacing the process completely. However, these are insufficient to achieve the deep carbon reductions required if we are to avoid dangerous climate change. The paper concludes with recommendations for action to achieve further decarbonisation.
Dean, C, Hills, T, Florin, N, Dugwell, D & Fennell, PS 2013, 'Integrating Calcium Looping CO2 Capture with the Manufacture of Cement', Energy Procedia, vol. 37, pp. 7078-7090.View/Download from: UTS OPUS or Publisher's site
This paper investigates the trace element content of calcium oxide sorbent after repeated cycles of calcination and carbonation in the presence of fuel combustion during the calcination step. The trace element content of the sorbent was measured using ICP-OES after a wet acid digestion procedure. The weight % of alite, the cement phase responsible for short-term strength of the cement, has been measured using XRD for cement prepared in the laboratory from single cycled and repeatedly cycled sorbent. The results indicate that repeated cycling does lead to an increase in the concentration of some trace elements entering the sorbent from the fuel. However the increase in these concentrations was not enough to impact upon the weight % of alite in the resulting clinkers produced from the sorbent
Hurst, TF, Cockerill, TT & Florin, N 2012, 'Life cycle greenhouse gas assessment of a coal-fired power station with calcium looping CO2 capture and offshore geological storage', Energy & Environmental Science, vol. 5, pp. 7132-7150.View/Download from: UTS OPUS or Publisher's site
Carbon Capture and Storage (CCS) is an essential technology for reducing global CO2 emissions in the context of continued fossil fuel use in the power sector. To evaluate the emission reduction potential of any low-carbon generation technology it is necessary to consider emissions over the entire lifetime of the plant. This work examines the lifecycle greenhouse gas emissions of a 500 MWe pulverised coal-fired power plant with post-combustion Calcium Looping (CaL) and off-shore geological storage. CaL uses solid CO2-sorbent derived from abundant and non-toxic limestone (CaCO3) and is currently being piloted at the 12 MWth scale in Europe (Spain and Germany). This technology promises to be very competitive with the more mature chemical absorption processes, with the potential to reduce the efficiency and cost penalties of CO2 capture. We demonstrate that the emission intensity of a coal-fired power plant with CaL is at least comparable with one using MEA-solvent technology (i.e., 229 gCO2e/kWh vs. 225 gCO2e/kWh). However, there is significant potential for additional emissions reduction when considering the recarbonation of exhausted sorbent in landfill. Furthermore, a coal-fired power plant with CaL could be carbon-neutral or even achieve a net removal of CO2 from the atmosphere. That is, if the exhausted sorbent is used in the cement industry substituting the input of fresh-limestone; or if the exhausted sorbent is disposed in the ocean forming bicarbonate.
Donat, F, Florin, N, Anthony, E & Fennell, PS 2012, 'Influence of High-Temperature Steam on the Reactivity of CaO Sorbent for CO2 Capture', Environmental Science & Technology, vol. 46, no. 2, pp. 1262-1269.View/Download from: UTS OPUS or Publisher's site
Calcium looping is a high-temperature CO2 capture technology applicable to the postcombustion capture of CO2 from power station flue gas, or integrated with fuel conversion in precombustion CO2 capture schemes. The capture technology uses solid CaO sorbent derived from natural limestone and takes advantage of the reversible reaction between CaO and CO2 to form CaCO3; that is, to achieve the separation of CO2 from flue or fuel gas, and produce a pure stream of CO2 suitable for geological storage. An important characteristic of the sorbent, affecting the cost-efficiency of this technology, is the decay in reactivity of the sorbent over multiple CO2 capture-and-release cycles. This work reports on the influence of high-temperature steam, which will be present in flue (about 510%) and fuel (20%) gases, on the reactivity of CaO sorbent derived from four natural limestones. A significant increase in the reactivity of these sorbents was found for 30 cycles in the presence of steam (from 120%). Steam influences the sorbent reactivity in two ways. Steam present during calcination promotes sintering that produces a sorbent morphology with most of the pore volume associated with larger pores of 50 nm in diameter, and which appears to be relatively more stable than the pore structure that evolves when no steam is present. The presence of steam during carbonation reduces the diffusion resistance during carbonation. We observed a synergistic effect, i.e., the highest reactivity was observed when steam was present for both calcination and carbonation.
The literature concerning the application of CCS to industry is reviewed. Costs are presented for different sectors including ``high purity'' (processes which inherently produce a high concentration of CO2), cement, iron and steel, refinery and biomass. The application of CCS to industry is a field which has had much less attention than its application to the electricity production sector. Costs range from less than $2011 10/tCO 2 up to above $ 2011 100/tCO 2 . In the words of a synthesis report from the United Nations Industrial Development Organisation (UNIDO) ``This area has so far not been the focus of discussions and therefore much attention needs to be paid to the application of CCS to industrial sources if the full potential of CCS is to be unlocked''.
The capture and purification of carbon dioxide (CO2) from flue or fuel gas underlies the cost efficiency of carbon capture and storage (CCS) applications in the power and industrial sectors and there is considerable scope for cost reduction with the development of novel capture technologies. High-temperature sorbents are seen as a next-generation technology and a promising candidate is calcium oxide (CaO) derived from natural limestone, which is used in a process known as carbonate looping. This process exploits the reversible reaction between CaO and CO2 to form calcium carbonate (CaCO3). Unfortunately, sorbent derived from natural limestone loses its capacity to capture CO2 through long-term cycling, and a large amount of fresh limestone is required to maintain an acceptable CO2 capture efficiency. This work describes the development and characterisation of synthetic CaO-based sorbents, such as those incorporating a mixed calcium-aluminium oxide binderin this case produced by precipitation in a slurry bubble column. Reactivity tests using a thermogravimetric analyser (TGA) demonstrate the improved long-term CO2 uptake of the synthetic sorbent. The highest CO2 uptake observed after 30 cycles was achieved with 85 wt.% CaO and binder, which was three times higher than the observed capacity of a natural limestone (Havelock). However, contrary to TGA results, experimental results for reactivity tests conducted using a bench-scale fluidised bed reactor (FBR) showed the highest uptake for the precipitated sorbent with no binder. A decrease in uptake was observed corresponding an increase in binder loading from 025 wt.%, which was coupled with an increase in mass loss owing to elutriation, attributed to decrepitation during cycling.
Dean, CC, Blamey, J, Florin, N, Al-Jeboori, M & Fennell, PS 2011, 'The calcium looping cycle for CO2 capture from power generation, cement manufacture and hydrogen production', Chemical Engineering Research & Design, vol. 89, no. 6, pp. 836-855.View/Download from: UTS OPUS or Publisher's site
Calcium looping is a CO2 capture scheme using solid CaO-based sorbents to remove CO2 from flue gases, e.g., from a power plant, producing a concentrated stream of CO2 (~95%) suitable for storage. The scheme exploits the reversible gassolid reaction between CO2 and CaO(s) to form CaCO3(s). Calcium looping has a number of advantages compared to closer-to-market capture schemes, including: the use of circulating fluidised bed reactorsa mature technology at large scale; sorbent derived from cheap, abundant and environmentally benign limestone and dolomite precursors; and the relatively small efficiency penalty that it imposes on the power/industrial process (i.e., estimated at 68 percentage points, compared to 9.512.5 from amine-based post-combustion capture). A further advantage is the synergy with cement manufacture, which potentially allows for decarbonisation of both cement manufacture and power production. In addition, a number of advanced applications offer the potential for significant cost reductions in the production of hydrogen from fossil fuels coupled with CO2 capture. The range of applications of calcium looping are discussed here, including the progress made towards demonstrating this technology as a viable post-combustion capture technology using small-pilot scale rigs, and the early progress towards a 2 MW scale demonstrator.
Widyawati, M, Church, T, Florin, N & Harris, AT 2011, 'Hydrogen Synthesis From Biomass Pyrolysis With In Situ Carbon Dioxide Capture Using Calcium Oxide', International Journal Of Hydrogen Energy, vol. 36, no. 8, pp. 4800-4813.View/Download from: UTS OPUS or Publisher's site
Hydrogen (H2) and other gases (CO2, CO, CH4, H2O) produced during the pyrolysis of cellulose, xylan, lignin and pine (Pinus radiata), with and without added calcium oxide (CaO), were studied using thermogravimetry-mass spectrometry (TG-MS) and thermodynamic modeling. CaO improved the H2 yield from all feedstocks, and had the most significant effect on xylan. The weight loss of and gas evolution from the feedstocks were measured over the temperature range 150950 °C in order to investigate the principle mechanism(s) of H2 formation. Without added CaO, little H2 was produced during primary pyrolysis; rather, most H2 was generated from tar-cracking, reforming, and char-decomposition reactions at higher temperatures. When CaO was added, significant H2 was produced during primary pyrolysis, as the water-gas shift reaction was driven toward H2 formation. CaO also increased the formation of H2 from reforming and char gasification reactions. Finally, CaO increased the extent of tar cracking and char decomposition, and lowered their onset temperatures. The production of H2 from pine over the course of pyrolysis could be modeled by summing the H2 evolutions from the separate biomass components in relevant proportions.
Zhao, M, Florin, N & Harris, AT 2010, 'Mesoporous supported cobalt catalysts for enhanced hydrogen production during cellulose decomposition', Applied Catalysis B: Environmental, vol. 97, no. 1-2, pp. 142-150.View/Download from: UTS OPUS or Publisher's site
Two groups of cobalt (Co) catalysts, supported on SBA-15 and MCM-41, respectively, were prepared by incipient wetness impregnation and tested for their influence on the thermal decomposition of acetyl cellulose. ?-Al2O3 supported Co catalysts were investigated as a comparison. A thermogravimetric analyser coupled with a mass spectrometer (TG-MS) was used to examine the influence of catalyst loading, support material and the presence of additional water vapour on H2 production and selectivity. Normalization of the raw MS data enabled semi-quantitative analysis of the product gas distribution, which facilitated reliable comparison between different experimental conditions. Catalysts were characterized by physisorption, chemisorption, TGA, XRD, SEM and TEM. SBA-15 and MCM-41 supported catalysts significantly elevated the yield and selectivity of H2, under dry Ar and with the injection of additional water vapour, when compared with the ?-Al2O3 support. 15 wt.%Co/SBA-15 and 10 wt.%Co/MCM-41 were identified as the most active catalysts from the two groups with indicative yields of 202 and 303 ml H2/g cellulose, respectively. The 10 wt.%Co/MCM-41 catalyst gave with the highest H2 selectivity reaching 21.7% of the dry product gas
Florin, N, Blamey, J & Fennell, PS 2010, 'Synthetic CaO-based sorbent for CO2 capture from large-point sources', Energy & Fuels, vol. 24, no. 8, pp. 4598-4604.View/Download from: UTS OPUS or Publisher's site
The main impetus for future technology development for capturing and purifying CO2 from industrial flue gases is the potential for minimizing the cost of capture and reducing the efficiency penalty that is imposed on the process. Carbonate looping is a very promising future technology, which uses CaO-based solid sorbents, with great potential to reduce the cost of capture and lessen the energy penalty compared to closer to market technologies, e.g., solvent scrubbing. Unfortunately, the CO2-capture capacity of a CaO-sorbent derived from natural limestone decays through long-term capture-and-release cycling; thus, the development of strategies and/or novel sorbents to achieve a high CO2-capture capacity is an important challenge for realizing the cost efficiency of carbonate looping technology. To this end, we report on the development and characterization of a novel synthetic CaO-based sorbent produced via a precipitation method and present experimental results demonstrating improved long-term CO2-capture capacity based on reactivity testing using a thermogravimetric analyzer (TGA) and a bench-scale bubbling fluidized-bed (BFB) reactor. We achieve a capture capacity of about 2.5 times the amount of CO2 after 15 cycles with the synthetic sorbent compared to a natural limestone (Havelock) in the BFB.
MacDowell, N, Florin, N, Buchard, A, Hallett, J, Galindo, A, Jackson, G, Adjiman, C, Williams, CK, Shah, N & Fennell, P 2010, 'An overview of CO2 capture technologies', Energy & Environmental Science, vol. 3, no. 11, pp. 1645-1669.View/Download from: UTS OPUS or Publisher's site
In this paper, three of the leading options for large scale CO2 capture are reviewed from a technical perspective. We consider solvent-based chemisorption techniques, carbonate looping technology, and the so-called oxyfuel process. For each technology option, we give an overview of the technology, listing advantages and disadvantages. Subsequently, a discussion of the level of technological maturity is presented, and we conclude by identifying current gaps in knowledge and suggest areas with significant scope for future work. We then discuss the suitability of using ionic liquids as novel, environmentally benign solvents with which to capture CO2. In addition, we consider alternatives to simply sequestering CO2-we present a discussion on the possibility of recycling captured CO2 and exploiting it as a C1 building block for the sustainable manufacture of polymers, fine chemicals, and liquid fuels. Finally, we present a discussion of relevant systems engineering methodologies in carbon capture system design.
Yang, Z, Zhao, M, Florin, N & Harris, AT 2009, 'Synthesis and Characterization of CaO Nanopods for High Temperature CO2 Capture', Industrial & Engineering Chemistry Research, vol. 48, no. 24, pp. 10765-10770.View/Download from: UTS OPUS or Publisher's site
A hollow structured CaO sorbent with high CO2 absorption capacity and good cyclic performance at high temperatures was derived from the corresponding CaCO3 precursor, which was prepared by bubbling gaseous CO2 through a Ca(OH)2 slurry in the presence of the triblock copolymer surfactant, P123 (PEO20PPO70PEO20). Field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images showed the novel sorbent to be comprised of nanosized platelets forming hollow particles resembling a pod of approximately 200 nm in diameter and up to 600 nm in length. Thermogravimetric analysis showed that the tailored sorbent had the highest CO2 absorption capacity when compared with calcines derived from precipitated CaCO3 without P123 and a commercially available CaCO3, retaining >50% CO2 absorption capacity after 50 CO2 capture-and-release cycles for carbonation temperatures from 600 to 700 °C.
Zhao, M, Florin, N & Harris, AT 2009, 'The influence of supported Ni catalysts on the product gas distribution and H2 yield during cellulose pyrolysis', Applied Catalysis B: Environmental, vol. 92, no. 1-2, pp. 185-193.View/Download from: UTS OPUS or Publisher's site
Two groups of Ni catalysts, supported on g-Al2O3 and MCM-41, respectively, were prepared by incipient wetness impregnation and tested for their influence on the pyrolytic decomposition of cellulose. A thermogravimetric analyser coupled with a mass spectrometer (TGMS) was used to examine the influence of catalyst loading, support material, and the presence of additional water vapour on H2 selectivity. Normalization of the raw MS data enabled semi-quantitative analysis of the product gas distribution, which facilitated reliable comparison between different experimental conditions. Catalysts were characterized by BET, XRD, SEM/EDX and TEM. MCM-41 supported Ni significantly elevated the yield of H2 and total gaseous product, both under Ar and with the injection of additional water vapour when compared with the g-Al2O3 support. 15 wt.%Ni/g-Al2O3 and 5 wt.%Ni/MCM-41 were identified as the most active catalysts from the two groups with regards to H2 selectivity and yield.
Florin, N & Harris, AT 2009, 'Reactivity of CaO derived from nano-sized CaCO3 particles through multiple CO2 capture-and-release cycles', Chemical Engineering Science, vol. 64, no. 2, pp. 187-191.View/Download from: UTS OPUS or Publisher's site
The carbonation characteristics of pure CaO derived from nano-sized CaCO 3 were investigated as part of a multi-cycle performance study which showed potential for exploiting the properties of nano-sized CaO sorbents in a continuous CO 2 capture-and-release process. To help understand the approach to the decay asymptote, which is established through multiple capture-and-release cycles, a qualitative model was proposed. The rate of approach and residual conversion defined by the decay asymptote represents the establishment of an equilibrium between the pore volume and surface area loss during thermal sintering; and the pore volume and surface area regeneration as a consequence of a solid-state diffusion mechanism, and the subsequent release of CO 2 in the next calcination cycle. This qualitative explanation is valid for all CaO derived CO 2 sorbents.
Florin, N, Maddocks, A, Wood, S & Harris, AT 2009, 'High-temperature thermal destruction of poultry derived wastes for energy recovery in Australia', Waste Management: international journal of integrated waste management, science and technology, vol. 29, no. 4, pp. 1399-1408.View/Download from: UTS OPUS or Publisher's site
The high-temperature thermal destruction of poultry derived wastes (e.g., manure and bedding) for energy recovery is viable in Australia when considering resource availability and equivalent commercial- scale experience in the UK. In this work, we identified and examined the opportunities and risks associated with common thermal destruction techniques, including: volume of waste, costs, technological risks and environmental impacts. Typical poultry waste streams were characterised based on compositional analysis, thermodynamic equilibrium modelling and non-isothermal thermogravimetric analysis coupled with mass spectrometry (TGMS). Poultry waste is highly variable but otherwise comparable with other biomass fuels. The major technical and operating challenges are associated with this variability in terms of: moisture content, presence of inorganic species and type of litter. This variability is subject to a range of parameters including: type and age of bird, and geographical and seasonal inconsistencies. There are environmental and health considerations associated with combustion and gasification due to the formation of: NOX, SOX, H2S and HCl gas. Mitigation of these emissions is achievable through correct plant design and operation, however, with significant economic penalty. Based on our analysis and literature data, we present cost estimates for generic poultry-waste-fired power plants with throughputs of 2 and 8 tonnes/h.
Florin, NH & Harris, AT 2008, 'Preparation and characterization of a tailored carbon dioxide sorbent for enhanced hydrogen synthesis in biomass gasifiers', INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, vol. 47, no. 7, pp. 2191-2202.View/Download from: Publisher's site
Florin, NH & Harris, AT 2008, 'Enhanced hydrogen production from biomass with in situ carbon dioxide capture using calcium oxide sorbents', CHEMICAL ENGINEERING SCIENCE, vol. 63, no. 2, pp. 287-316.View/Download from: Publisher's site
Florin, NH & Harris, AT 2008, 'Mechanistic study of enhanced H-2 synthesis in biomass gasifiers with in-situ CO2 capture using CaO', AICHE JOURNAL, vol. 54, no. 4, pp. 1096-1109.View/Download from: Publisher's site
Florin, N, Boot-Handford, M & Fennell, P 2015, 'Calcium looping technologies for gasification and reforming' in Boot-Handford, M & Fennell, P (eds), Calcium and Chemical Looping Technology for Power Generation and Carbon Dioxide (CO2) Capture, Elsevier, The Netherlands, pp. 139-152.View/Download from: UTS OPUS or Publisher's site
This chapter demonstrates the broad potential of applying calcium looping for reforming and gasification applications. The highly integrated processes discussed herein offer potential step-change improvements in the thermal and cost efficiency of power production integrated with CO2 capture. While there has been a considerable amount of research focussed on elaborating the underlying science, there remains scope for further work to evaluate the reaction kinetics for sorption-enhanced water–gas shift and sorption-enhanced reforming, to measure the influence of impurities, and to overcome challenges associated with complex process integration.
Florin, N, Sharpe, S, Wright, S & Giurco, D 2015, 'Business models for a circular world: the case of metals' in Ludwig, C, Matasci, C & Edelmann, X (eds), Part IV Circular Economy and Decoupling, Natural Resources: Sustainable targets, Technologies, Lifestyles and Governance, Paul Scherrer Institute, Switzerland, pp. 253-259.View/Download from: UTS OPUS
Florin, N., MacDowell, N. & Fennell, P. 2012, 'Carbon Capture: Materials & Process Engineering' in Letcher, T.M. & Scott, J.L. (eds), Materials for a Sustainable Future, The Royal Society of Chemistry, Cambridge, pp. 385-429.View/Download from: UTS OPUS
The global challenge of achieving the major reductions in CO2 emissions necessary to mitigate climate change cannot be overstated. It will require a wide range of strategic actions, including end-use energy efficiency, changing public attitudes and behaviour to reduce demand and increasing the use of renewable energy sources and nuclear power. Despite the increased deployment of the latter over the next few decades, to meet the world's growing energy needs it will be necessary to continue to use fossil fuels well into the second half of the century. We must therefore capture as much as possible of the CO2 released in their production and use (for power generation, industrial processes, etc.) and store it in suitable underground locations - so-called carbon capture and storage (or sequestration) (CCS).
Madden, B, Florin, N & Giurco, D 2016, 'Assessment of waste to energy as a resource recovery intervention using system dynamics: A case study of New South Wales, Australia', Life Cycle Assessment and Other Assessment Tools For Waste Management and Resource Optimisation, Grand Hotel San Michele.View/Download from: UTS OPUS
Driven by an increasing population, affluence and economic activity, waste—an almost inevitable by-product of modern production and consumption—is being generated at a rate that is growing exponentially with time in Australia. Despite the global maturity of waste to energy technology as a waste valorisation process, it is yet to be applied at scale in Australia, which has traditionally relied on landfill disposal, and more recently recycling, for the management of waste. Recent policy frameworks implemented have enabled the uptake of waste to energy in parts of Australia to divert waste from landfill, while offsetting non-renewable energy sources in the transition to a low-carbon energy landscape. However, recent policy dictates that higher order waste valorisation processes such as re-use and recycling, must not be undermined by energy recovery processes.
In this paper, we present initial findings from a system dynamics model, developed to assess interventions to improve resource recovery in a multi-stream (municipal, construction and commercial) waste system specific to New South Wales. The system under investigation is characterised by causal feedback processes between waste generation, valorisation processes, and waste management policies, making it ideal for study using a system dynamics approach, and offers benefits in terms of greater understanding of the system processes over more typical mechanistic approaches . System dynamics modelling has been used in the study of sustainable waste management, and waste management planning (see , , and ), and has yet to be applied in the context of waste to energy in Australia. Using socioeconomic and waste management data as inputs, projected waste generation and recycling rates under reference conditions are compared to scenarios with waste to energy intervention, to estimate the potential of energy recovery in achieving local waste management targets. Several scenarios are modelled with variation in al...
McLellan, B, Florin, N, Giurco, D, Kishita, Y, Itaoka, K & Tezuka, T 2015, 'Decentralised energy futures: the changing emissions reduction landscape', Procedia CIRP, CIRP Life Cycle Engineering Conference, Elsevier, Sydney, pp. 138-143.View/Download from: UTS OPUS or Publisher's site
The world is witnessing an energy revolution as renewables become more competitive and energy security becomes a high priority for an increasing number of countries. This development is changing the point along the supply chain ripe for reducing emissions. Whereas carbon capture and storage (CCS) coupled to coal or gas power production offers the potential to decarbonise the current centralised power systems, this relies on a significant increase in electrification to achieve deep emission reductions beyond the power sector, including industrial emissions and transportation. At the same time there is a trend towards decentralised industrial processes, e.g., driven by cost reductions in decentralised production systems and miniature processing plant. New strategies for reducing emissions from decentralised industrial and energy emission point sources will be increasingly important. This paper evaluates different emission reduction strategies that may be relevant to a decentralised energy and manufacturing future, including increased electrification, energy storage, renewable energy and renewable feedstock. Systemic opportunities or barriers and considerations of policy and decentralised decision-making are examined.
Florin, N, Hills, T, Zheng, L & Fennell, P 2015, 'Characteristics and performance of Portland cement made from looped sorbent from CaL process', 6th IEA High Temperature Solids Looping, Politecnico di Milano, Milan, Italy.
Al-Jeboori, M., Zhang, Z., Blamey, J., Hills, T.P., Florin, N., Anthony, E., Manovic, V. & Fennell, P.S. 2013, 'CaO-based sorbent and chemical looping technology', IEA High Temperature Solids Looping, Cambridge.
Zhao, M, Florin, N, Fennell, P & Harris, A 2012, 'Synthesis of CaO-scaffold adsorbent with superior stability for high-temperature CO2 capture', AIChE Annual Meeting.
Florin, N., Dean, C., Al-Jeboori, M. & Fennell, P.S. 2011, 'Activation of limestone derived sorbent for CO2 capture', Carbon Capture Research Event CO2Chem Network and the UK Carbon Capture & Storage Community, East Midlands Conference Centre, University of Nottingham.
Florin, N., Donat, F. & Fennell, P.S. 2014, 'Influence of High-Temperature Steam on the Reactivity of CaO Sorbent', IEA High Temperature Solids Looping, Vienna.
Florin, N., Donat, F. & Fennell, P.S. 2011, 'Influence of high-temperature steam on the reactivity of CaO sorbent', 1st International Workshop on Oxy-fuel fluidised bed combustion, Ottawa, Ontario, Canada.
Florin, N., Blamey, J., Al-Jeboori, M. & Fennell, P.S. 2010, 'Modification of CaO-based sorbent: current work at Imperial College London', IEA High Temperature Solids Looping, Amsterdam.
The 'hydrogen economy' has received considerable attention in academic, industrial and political contexts. There are opportunities for vast reductions in greenhouse gas emissions, increased energy security and greater overall efficiency. However, if hydrogen is to become a fundamental energy source for electrical power generation, as well as a transportation fuel, novel generation pathways will be necessary to meet the increase in demand. A promising means for generating hydrogen is the thermochemical conversion of biomass to a synthesis gas, composed of a mixture of hydrogen, carbon monoxide, carbon dioxide and methane. In order to manipulate the composition and maximise the hydrogen output, a calcium-based carbon dioxide sorbent can be utilised in situ. The removal of carbon dioxide alters the reaction chemistry to preferentially produce hydrogen. In this work we report on the characterisation of a likely Ca-based carbon dioxide sorbent and demonstrate the merits of hydrogen production from biomass, with in situ carbon dioxide capture, on the basis of a thermodynamic study. Using this model we show that hydrogen output from biomass gasification can be increased from 40%-vol to 80%-vol (dry basis) when a carbon dioxide sorbent is used. © 2007 Springer Science+Business Media, LLC.
Dominish, E, Florin, N, Giurco, D, Corder, G, Golev, A, Lane, R, Rhamdhani, A, Reck, B, Graedel, T, Sharpe, S, Edwards, M, Benn, S & Brooks, G 2017, Australian Opportunities in a Circular Economy for Metals: Findings of the Wealth from Waste Cluster, Sydney, Australia.View/Download from: UTS OPUS
Florin, N, Madden, B, Sharpe, S, Benn, S, Agarwal, R, Perey, R & Giurco, D University of Technology Sydney 2015, Shifting Business Models for a Circular Economy: Metals Management for Multi-Product-Use Cycles, pp. 1-90, Sydney, Australia.
The overarching aim of this report is to explore how the Australian metals and minerals sector could embrace new business models and build on its strengths to harness new value in a global economy orientated more towards sustainable futures
Australia exports some EPS to be recycled overseas, but we have less than one collection point per state. All of this means that The NSW Evironmental Protection Agency estimates that some 12,000 tonnes of EPS is sent to landfill every year. According to the Australian Plastics Recycling survey, about 14% of EPS is recovered for recycling. Most of that is exported – only around 1.6% of all the EPS used in Australia is recycled here.
This is why many researchers are looking for ways to re-purpose EPS, taking advantage of this very useful material and keeping it out of landfill.