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Understanding past fire regimes and how they vary with climate, human activity, and vegetation patterns is fundamental to the mitigation and management of changing fire regimes as anthropogenic climate change progresses. Ash‐derived trace elements and pyrogenic biomarkers from speleothems have recently been shown to record past fire activity in speleothems from both Australia and North America. This calls for an empirical study of ash geochemistry to aid the interpretation of speleothem palaeofire proxy records. Here we present analyses of leached ashes collected following fires in southwest and southeast Australia. We include a suite of inorganic elemental data from the water‐soluble fraction of ash as well as a selection of organic analytes (pyrogenic lipid biomarkers). We also present elemental data from leachates of soils collected from sites in southwest Australia. We demonstrate that the water‐soluble fraction of ash differs from the water‐soluble fraction of soils, with trace and minor element concentrations in ash leachates varying with combustion completeness (burn severity) and sample location. Changes in some lipid biomarker concentrations extracted from ashes may reflect burn severity. Our results contribute to building a process‐based understanding of how speleothem geochemistry may record fire frequency and severity, and suggest that more research is needed to understand the transport pathways for the inclusion of pyrogenic biomarkers in speleothems. Our results also demonstrate that potential contaminant loads from ashes are much higher than from soils, with implications for the management of karst catchments, which are a critical water resource. Plain Language Summary: Understanding past fire activity is necessary to develop effective land management strategies to manage activity. Recently, stalagmites (naturally forming cave decorations) have been shown to record past fire information through chemical changes. The chemical changes are due to post‐fire leaching of wildfire ash. By investigating wildfire ash chemistry, we will be able to improve our interpretations of the stalagmite past fire signal. Our results show that ash chemistry from Australian fires varies with burn severity and sample location, and that the ash chemistry and soil chemistry differ. Results suggest that stalagmites may record burn severity as well as fire frequency. We also suggest that the potential impact of high concentrations of potential contaminants in wildfire ash on karst aquifers should be further investigated. Key Points: Stalagmites record past fire activity through changes in inorganic and organic chemistry sourced from ashesWildfire ash leachate chemistry will aid interpretation of proxy fire dataResults show that inorganic chemistry varies with burn severity and sample location, and the pyrogenic biomarker signal is less clear [ABSTRACT FROM AUTHOR]

This study examined the effects of commonly used oxidants in sedimentary macroscopic charcoal analysis on two sediment cores from Thirlmere Lakes National Park, Southeast Australia. The cores, from Lake Werri Berri (WB3) and Lake Couridjah (LC2), span ~900 years and 135,000 years, respectively. The Charcoal Accumulation Rate (CHAR) for both charcoal area and count was quantified using four different chemical treatments and compared to a control using only water. We also quantified the Charring Intensity (CI) of isolated charcoal fragments, a proxy for the severity/intensity of fire, determined using the FTIR spectral characteristics of the remaining charcoal after each treatment. We found significant differences in both the area and number of particles across all treatments in both cores. Significantly, we found substantial differences in CI between treatments, with few charcoal particles formed in low-severity fire (e.g., below ~400 °C or 3.0 °C.s.106) in groups treated with an oxidant. In contrast, the control group displayed a wider range of CI values and contained lightly pyrolyzed particles. This suggests that methods using an oxidant to concentrate sedimentary charcoal are potentially biasing records towards high-intensity or -severity fires. We suggest that consideration should be used when choosing laboratory methods based on the hypotheses being tested. [ABSTRACT FROM AUTHOR]

We establish a framework to examine the feasibility of using local vegetation for bioenergy power systems in small-scale applications and remote settings. The framework has broad application, and we present a specific case here to demonstrate the process. Our case study is the Tiwi Islands in northern Australia, where a large Acacia mangium plantation is a potential source of biofuel feedstock. Two types of technology were considered: 1. Bio-oil from pyrolysis in diesel generators and 2. Direct combustion coupled with a steam turbine. The biomass was characterized and found to have adequate properties for an energy crop, with a lower heating value of about 18 MJ/kg and entire tree ash content of 2%. Measurements from trees that were damaged from wildfires had similar results, showing potential value recovery for a plantation after unplanned fire. In comparison to a petroleum diesel-based generator, the bio-oil system was 12% more expensive. The direct combustion system was found to be the most economical of those explored here, costing as low as 61% of the bio-oil system. Additional social and environmental benefits were identified, including local employment opportunities, improved energy security and reduced greenhouse gas emissions. Our findings of high techno-economic potential of bioenergy systems, especially through direct combustion, are widely applicable to on-demand renewable energy supply in remote communities. [ABSTRACT FROM AUTHOR]

Half‐butt eucalypts (genera: Eucalyptus and Corymbia) have both thick outer bark at the stem base (half‐butt) conferring resistance to surface fire, and thin photosynthetic canopy bark that reduces moisture stress. Here we examine how the functional ecology of dual outer bark types influences the wide distribution of Australian half‐butt species. We evaluate the proposition that half‐butts should predominate in semi‐arid environments prone to surface fires. We measured the bark thickness, butt height relative to flame/fire char height and tree height, height of first branch, and the location and prevalence of epicormic resprouting of co‐occurring Eucalyptusminiata (half‐butt) and E. tetrodonta (fibrous bark only) individuals, across 15 sites with contrasting fire frequencies (2000–2015) in the Darwin region. Total tree height was compared with butt height for all E. miniata individuals. The survival of half‐butt and other eucalypt species, as well as non‐eucalypts, was investigated at three sites affected by intense gamba grass (Andropogon gayanus) fire. The proportion of half‐butt species in each of Australia's 85 bioregions was calculated from geographic distribution records of 618 eucalypt species. Mean annual fire frequency (1997–2010), fire type (crown or surface fires) and climate in each bioregion was determined from satellite‐derived records. Butt height at a site, including gamba grass sites, was not induced by flame height or affected by fire frequency and was approximately half the canopy height of the tree, suggesting it is internally regulated. The half‐butt E. miniata and full‐bark eucalypts were similarly resilient (survival) under surface fire conditions. Half‐butt species predominated in arid and semi‐arid bioregions characterised by surface fire, consistent with our proposition that half‐butt bark is an adaptation to surface fire, and thin photosynthetic outer canopy bark reduces moisture stress, accounting for the wide distribution of half‐butt eucalypts in arid and seasonally dry regions of Australia. [ABSTRACT FROM AUTHOR]

The present study aimed to determine moisture thresholds for combustion of organic soils sampled from various vegetation types at 63 locations in Tasmania, Australia. To observe whether the soil sample sustained smouldering combustion, moisture content was experimentally manipulated and heat was applied. Combustion was primarily determined by moisture content, but was also influenced by soil bulk density and organic content: the gravimetric moisture content corresponding to a 50% probability of burning ranged from 25 to 94% as organic content varied from 34 to 96%. There was no evidence of differences among vegetation types in the relationship between soil combustibility and organic content. Combustion in Tasmanian organic soils occurred with moisture levels similar to those reported elsewhere, despite differences in vegetation and environment. It was also found that a hand-held meter that measured volumetric moisture content using time domain reflectometry could be used to satisfactorily predict organic soil combustion. Finally, combining the data with estimates of volumetric soil moisture based on high-resolution gridded weather data (Bureau of Meteorology Atmospheric high-resolution Regional Reanalysis for Australia, or BARRA), it was demonstrated that most Tasmanian organic soils are likely to be combustible at some time almost every summer (December to February). We experimentally determined the combustibility of organic soils from representative Tasmanian vegetation communities. We found soil combustion was primarily determined by moisture content, with a slight influence of organic content. Analysis of meteorological data shows most Tasmanian organic soils are probably combustible for at least a few days each summer. [ABSTRACT FROM AUTHOR]

Abstract Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5% of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing <1% of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60%. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μ g Hg kg−1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 × 10−7, for estimation of mercury release from the combustion of Australian dry sclerophyll litter. Highlights • Wildfire mercury release from eucalypt forests is currently overestimated by 60%. • Under natural wildfire fuel moistures, 99% of release is elemental mercury. • Fire progression impacts heavily; most mercury is released during flaming stage. • Recommended emission ratio for GEM/CO is 0.58 ± 0.01 × 10−7. [ABSTRACT FROM AUTHOR]

Leaf flammability is a multidimensional plant functional trait with emerging importance for wildfire risk management. Understanding relationships among leaf flammability attributes not only provides information about the properties of leaves as fuels in the wildland–urban interface (WUI), it can also offer an effective way to identify low-leaf-flammability species. We examined relationships between leaf ignitibility, sustainability and combustibility among 60 plant species of the WUI of eastern Australia. We found that leaf ignitibility and sustainability worked in opposition to each other as dimensions of flammability. Species with leaves that were slow to ignite were those with leaves that sustained burning for the longest, whereas species with leaves that were fast to ignite had leaves that burned for the shortest periods of time. Low leaf combustibility was related to short leaf burning sustainability but not to ignitibility. We created an overall leaf flammability index (OLFI) to rank species on emergent properties of ignitibility, sustainability and combustibility attributes in combination. We found that low-leaf-flammability species with low OLFI values had small leaf area, high leaf mass per area and high leaf water content. Our findings have implications for species selection for green firebreaks in the WUI. Analyses of relationships among flammability attributes showed that slow leaf ignitibility was correlated with long leaf burning sustainability, and vice versa. Low leaf combustibility was related to short leaf sustainability. Low overall leaf flammability was related to small leaf area, high leaf mass per area and high leaf water content. [ABSTRACT FROM AUTHOR]

The manipulation of fire is a technological act. The identification of the archaeological signatures of the controlled use of fire has important implications not only for the estimations of the origins and functions of the first fireplaces but also for our understanding of prehistoric technological development and resource use. At Riwi (Kimberley region, Western Australia), excavations over two field seasons have revealed a discontinuous occupation sequence over the past 45 ka, showing numerous, different combustion features interspersed within the deposit. Anthracological and micromorphological investigations at Riwi Cave indicate that the combustion features at the site can be categorised into three types: flat combustion features (type A), dug combustion features (type B) and thick accumulations of mixed combustion residues (type C). These provide evidence for two kinds of combustion practice: (i) fires lit directly on the ground and most likely not re-used and (ii) ground ovens, the latter appearing some 10,000 years after the first evidence for occupation of the site. A comparison of the wood species identified within these combustion features with those from equivalent scattered context levels, enables an exploration of the potential factors influencing wood selection and fire use through time at the site. A detailed understanding of the relationship between wood charcoal remains and archaeological context yields significant information on changes to environmental context and site occupation patterns over time. [ABSTRACT FROM AUTHOR]

We developed a gain–loss approach to estimating the dynamics of the dead organic matter pool in northern Australian savannas consistent with the Intergovernmental Panel on Climate Change 2006 guidance. Previously, only emissions of methane and nitrous oxide were accounted in greenhouse gas budgets. The new approach is based on a modification of the Olson fuel accumulation equation. This modification includes the mean post-fire residue and accounts for losses from both fire and decomposition and for gains from grass production, tree litter fall and the death of trees. We apply the approach to a case study in western Arnhem Land, Northern Territory, Australia, in which the fire regime has been changed and the project has achieved recognised abatement of methane and nitrous oxide emissions. The carbon sequestration in the dead organic matter is ~85 times the annual emissions abatement in this project area and when expressed as an annual rate is ~3.5 times the abatement. We also show that the emissions abatement has previously been underestimated owing to an inability to fully account for dead organic matter dynamics. Future work could refine the models of dead organic matter to include seasonal dynamics in inputs. [ABSTRACT FROM AUTHOR]

Fire is a keystone ecological process in many ecosystems. In such ecosystems, the exclusion of fire can lead to fundamental shifts in vegetation structure, composition and distribution and poses a major threat to the biodiversity dependent on these habitats. Programmes to manage and restore native vegetation have increased rapidly over recent decades, and while many such programmes have demonstrable success managing a range of environmental threats, their effectiveness in identifying and addressing the major threat of fire exclusion in fire-dependent vegetation is questionable. This study sought to identify impediments to the management of fire-excluded vegetation at the assessment and planning stage of ecological management programmes in Byron Shire in north-east New South Wales. Sixty ecological management and restoration plans for sites known to be fire-excluded in the shire were reviewed to determine the rate at which fire exclusion was identified and addressed in planning over the last decade. Document analysis found the majority of plans failed to accurately identify fire exclusion or to recommend the reintroduction of fire in fire-excluded management sites. Absence of standardised guidelines that require comprehensive consideration of fire exclusion in ecological management and restoration plans is suggested as a key factor in the low response rates observed. Furthermore, it was found that existing implicit prompts to address inappropriate-fire regimes generally, including government policies, project objectives and site-assessment prompts had little effect on identification and response rates, further confirming the need for more-explicit assessment prompts relating to fire-frequency issues. Without improvements of the current ecological assessment and planning process to increase identification and management of fire exclusion in the study area, fire-dependent biodiversity values will continue to decline wherever fire exclusion remains unmanaged. It is recommended that explicit assessment and planning templates are developed and implemented to effectively manage fire exclusion and conserve the fire-dependent biodiversity of Byron Shire and the far north coast of NSW. [ABSTRACT FROM AUTHOR]

In this paper, we present improvements to postcombustion capture ( PCC) processes based on aqueous monoethanolamine ( MEA). First, a rigorous, rate-based model of the carbon dioxide (CO2) capture process from flue gas by aqueous MEA was developed using Aspen Plus, and validated against results from the PCC pilot plant trials located at the coal-fired Tarong power station in Queensland, Australia. The model satisfactorily predicted the comprehensive experimental results from CO2 absorption and CO2 stripping process. The model was then employed to guide the systematic study of the MEA-based CO2 capture process for the reduction in regeneration energy penalty through parameter optimization and process modification. Important process parameters such as MEA concentration, lean CO2 loading, lean temperature, and stripper pressure were optimized. The process modifications were investigated, which included the absorber intercooling, rich-split, and stripper interheating processes. The minimum regeneration energy obtained from the combined parameter optimization and process modification was 3.1 MJ/kg CO2. This study suggests that the combination of a validated rate-based model and process simulation can be used as an effective tool to guide sophisticated process plant, equipment design and process improvement. [ABSTRACT FROM AUTHOR]

The capacity to predict fire dynamics in fuel beds comprised of live and dead fuel components is constrained by our limited understanding of the effects of live fuels on fire propagation. A field-based experimental burning program was conducted to specifically address the effect of the degree of curing, the proportion of dead fuels in the fuel bed, on fire propagation in grasslands. Experimental fires were conducted at two sites characterised by structurally distinct fuels with curing levels varying between 20% and 100%. Fire sustainability experiments showed that fire propagation can occur down to curing levels as low as 20%. Rate of fire spread varied between 41.7 and 102 m min-1 in fully cured fuels and between 2.8 and 43.5 m min-1 in partially cured grasslands. The degree of curing was found to be the best variable describing the damping effect of live fuels in a natural, senescing grassland. Live fuel moisture content by itself was not found to be related to the damping effect of live fuels on the rate of fire spread. Existing models for the effect of grass curing on fire behaviour presently used in Australia were found to under-predict the rate of forward fire spread in partially cured grasslands. A new curing relationship for southern Australian grasslands derived from the study results is proposed. [ABSTRACT FROM AUTHOR]

This before-and-after-impact study uses the natural abundance N isotope ratio (δN) to investigate the effects of a wildfire on sub-alpine ecosystem properties and processes. We measured the N signatures of soil, charred organic material, ash and foliage in three sub-alpine plant communities (grassland, heathland and woodland) in south-eastern Australia. Surface bulk soil was temporarily enriched in N immediately after wildfire compared to charred organic material and ash in all plant communities. We associated the enrichment of bulk soil with fractionation of N during combustion and volatilization of N, a process that also explains the sequential enrichment of N of unburnt leaves > ash > charred organic material in relation to duration and intensity of heating. The rapid decline in N of bulk soil to pre-fire values indicates that depleted ash, containing considerable amounts of total N, was readily incorporated into the soil. Foliar δN also increased with values peaking 1 year post-fire. Foliar enrichment was foremost coupled with the release of enriched NH into the soil owing to isotopic discrimination during volatilization of soluble N and combustion of organic material. The mode of post-fire regeneration influenced foliar N enrichment in two species indicating use of different sources of N following fire. The use of natural abundance of N in soil, ash and foliage as a means of tracing transformation of N during wildfire has established the importance of combustion products as an important, albeit temporary source of inorganic N for plants regenerating after wildfire. [ABSTRACT FROM AUTHOR]

Corrosion is a major operational issue in amine treating plants. With the likely application of CO2 capture technologies to coal combustion flue gases, corrosion rates in gas streams containing oxygen are of interest and evaluation of potential construction materials under realistic conditions is essential. A total of 128 corrosion coupons were installed at the Tarong Post Combustion Capture (PCC) pilot plant in 8 locations during operation with 30 wt% monoethanolamine (MEA). Each corrosion test location contained 4 coupons of each type of metal (316L, 316L welded, C1018, C1018 galvanized). Coupons were installed in the pilot plant for 4296 or 5448 h; however plant operation was intermittent with actual operating times of 593 or 745 h. The highest corrosion rates were observed for carbon steel (C1018) and galvanized carbon steel (C1018 GLV) coupons located in both the absorber and stripper solvent storage tanks. C1018 GLV coupons typically showed higher rates of corrosion than C1018 coupons. C1018 coupons located in the absorber wash section also exhibited high corrosion rates, while C1018 GLV coupons in the same location did not. XRD analysis showed that the galvanized coupons in the absorber wash section retained some Zn in the corrosion scale. This could have aided their resistance to corrosion in this location. All other galvanized samples lost their zinc coating, indicating galvanizing might not be appropriate for use in CO2 capture applications. C1018 coupons in the absorber column experienced pitting. This was not seen for the galvanized coupons. In the stripping column, both the C1018 and C1018 GLV coupons showed areas of general corrosion attack. Stainless steel and welded stainless steel coupons showed no appreciable corrosion weight loss under the conditions tested. The corrosion resistance of the 316L stainless steel coupons to all environments considered here suggests it is suitable for use in all areas of amine based PCC plants. The corrosion rates measured on C1018 and C1018 GLV coupons suggest these materials would not be recommended for use in solvent storage tanks or wash sections of PCC plants. Due to intermittent use of the plant, it is unclear from these results whether C1018 or C1018 GLV would be suitable for use in the absorption/desorption columns. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Fuel moisture is the most dynamic component of bushfire fuels. It varies rapidly both spatially and temporally and plays a significant role in determining the behaviour and spread of bushfires, particularly through combustibility and ease of ignition of dead fine fuels (i.e. particle diameter <6 mm). The Kilmore East fire in Victoria, Australia, on 7 February, 2009 (“Black Saturday”) was the most destructive bushfire in Australia''s history. Its behaviour was characterised by mass spotting (the launch, transport and landing of burning firebrands that ignited new fires downwind of the main fire), an indication of low fine surface fuel moisture content (FMC). However, no direct measurements of FMC were taken during the run of the fire. Existing point-based models of dead fine FMC of grass and forest litter fuels were used in conjunction with historical weather, topographic and fuel data for the fire area to investigate the likely spatial and temporal variation in landscape FMC during the event for the purpose of reconstructing the fire''s propagation. To assess model performance, output was compared with the only suitable fuel moisture data collected in the region of the fire, measured at two locations ten days after the event. The model was found to be within 1% under adsorption conditions at one location and within 33% under desorption conditions at the other. The model was also used to study the effect of an intensive five day heatwave in the week prior to the fire event on FMC. In the absence of the heatwave, predicted FMC was 2.5 times higher than with the heatwave, however the effect of increased FMC was short-lived and would not have had a direct impact on the fine FMC during the fire event a week later, although it may have affected live fuels or larger dead fuels. [Copyright &y& Elsevier]

Australian power generators produce approximately 170 TWh per annum of electricity using black and brown coals that accounts for 170 Mtonne of CO2 emissions per annum or over 40% of anthropogenic CO2 emissions in Australia. This paper describes the results of a techno-economic evaluation of liquid absorption based post-combustion capture (PCC) processes for both existing and new pulverised coal-fired power stations in Australia. The overall process designs incorporate both the case with continuous capture and the case with the flexibility to switch a CO2 capture plant on or off depending upon the demand and market price for electricity, and addresses the impact of the presently limited emission controls on the process cost. The techno-economic evaluation includes both air and water cooled power and CO2 capture plants, resulting in cost of power generation for the situations without and with PCC. Whilst existing power plants in Australia are all water cooled sub-critical designs, the new power plants are deemed to range from supercritical single reheat to ultra-supercritical double reheat designs, with a preference for air-cooling. The process evaluation also includes a detailed sensitivity analysis of the thermodynamic properties of liquid absorbent for CO2 on the overall costs. The results show that for a meaningful decrease in the efficiency and cost penalties associated with the post combustion CO2 capture, a novel liquid sorbent will need to have heat of absorption/desorption, sensible heat and heat of vaporisation around 50% less in comparison with 30% (w/w) aqueous MEA solvent. It also shows that the impact of the capital costs of PCC processes is quite large on the added cost of generation. The results can be used to prioritise PCC research in an Australian context. [ABSTRACT FROM AUTHOR]

Abstract: Commissioned in 2009, the CO2CRC/H3 Capture Project is demonstrating post-combustion carbon capture (PCC) on a lignite fired power plant in the Latrobe Valley, Victoria, Australia. The facility is located within International Power’s Hazelwood Power Plant and uses three different CO2 capture technologies — solvent, adsorption and membrane processes. This project, addressing the PCC issues specific for Victorian brown coal fired power stations, was initiated in July 2007 as a three year research project by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) under the Victorian State Government’s Energy Technology Innovation Strategy (ETIS) program. The project is part of the Latrobe Valley Post Combustion Capture (LVPCC) Project — a multi site, multi scale, multi technology PCC trial. The integrated research and development program includes an evaluation of these technologies for commercial scale application. This paper describes the technologies used, how they have progressed from laboratory to pilot demonstration, the main outcomes, and plans for future developments. [Copyright &y& Elsevier]

Abstract: A techno-economic comparative assessment is made for an amine based post-combustion capture (PCC) process applied to representative coal-fired power plants in Australia and China. The assessment is based on an in-depth analysis of the cost of generation. The process and cost models for integrated power and capture plants have been obtained using ASPEN Rate-Sep, Steam-Pro, Steam-Master and PEACE software packages for process modelling and cost estimation. The equipment costs as well as the fuel costs have been based on the national experiences and circumstances. Important differences between PCC in China and Australia have been identified: [-] the limited environmental controls in existing Australian coal fired power stations requiring a retrofit to include extensive flue gas pre-treatment, [-] the low fuel cost in Australia as power plants are closely located to coal mines [-] the low capital costs in China as a result of lower local manufacturing costs. The results indicate that PCC in China can benefit significantly from more energy efficient processes, whereas for the Australian circumstances the focus should be on reduction of capital costs. [Copyright &y& Elsevier]

Abstract: This paper estimates the cost of CO2 capture for three Australian industrial emission sources: iron and steel production, oil refineries and cement manufacturing. It also compares the estimated capture costs with those of post-combustion capture from a pulverised black coal power plant. The cost of capture in 2008 using MEA solvent absorption technology ranges from less than A$60 per tonne CO2 avoided for the iron and steel production to over A$70 per tonne CO2 avoided for cement manufacture and over A$100 per tonne CO2 avoided for oil refineries. The costs of capture for the iron and steel and cement industries are comparable to or less than that for post-combustion capture from a pulverised black coal power plant. This paper also investigates costs for converting low partial pressure CO2 streams from iron and steel production to a more concentrated stream using pressurisation and the water-gas shift reaction. In those cases, the costs were found to be similar to or less than the cost estimates without conversion. The analyses in this paper also show that estimated costs are highly dependent on the characteristics of the industrial emission source, the assumptions related to the type and price of energy used by the capture facilities and the economic parameters of the project such as the discount rate and capital costs. [ABSTRACT FROM AUTHOR]

Abstract: A 25 TPD post-combustion CO2 capture plant for brown coal and a 0.5TPD pre-combustion CO2 capture IGCC process have been designed and are being built in Victoria, Australia to assess developments in solvent absorption capture technologies. In this paper, the flowsheets developed for these processes will be discussed along with the underpinning research in the following areas: [•] New contact equipment — recent work has shown that the SMR packing has enhanced performance over structured packing and standard Pall rings. [•] The influence of promoters to enhance kinetics - using a wetted-wall column, experiments have been conducted with boric acid added to potassium carbonate solvent with results showing an enhancement in CO2 absorption rates. [•] The influence of flue gas impurities - post-combustion impurities, including SO x and NO x , have been studied with potassium carbonate to evaluate their effects on CO2 absorption. [•] Process modeling — ASPEN Plus™ simulations have been developed to predict column performance and the effects of impurities on the equilibrium relationship. [Copyright &y& Elsevier]

Abstract: Post-combustion capture of CO2 is a key technology for the reduction of greenhouse gas emissions from Australian coal fired power stations. It is an emerging technology, which still faces significant challenges in scaling up to full commercial scale suitable for power station applications. To increase adoption by the power industry significant cost reductions in capital and operating cost must be realised. CSIRO has developed an integrated post-combustion capture R&D and pilot plant program aimed at bringing down the barriers for commercial deployment. This paper provides an overview of the program and its status. [Copyright &y& Elsevier]

Emissions of mercury to the atmosphere are being examined carefully because mercury tends to bio-accumulate in human food. products, particularly fish, at levels of concern. In this review our current understanding of the sources of mercury emission to the atmosphere and the speciation and chemistry of atmospheric mercury, are summarised. Estimations of anthropogenic and natural mercury (Hg) emissions from Australia in 2001 have been made. These suggest that total annual anthropogenic mercury emissions were about 10.2 tonnes. This estimate might. be increased by a further 2.6 tonnes were mercury emissions included from combustion of vegetation in wildfires (often caused as a result of human intervention), burning as part of fuel reduction/regeneration programs and burning carried out during land clearing and agriculture. Mercury derived from natural sources (including re-emission) was estimated to be in the range 117- 567 tonnes/annum, with the lower value probably being more reasonable. It is clear from the current study that estimation of mercury emission inventories is subject to large uncertainties. According to the latest global anthropogenic mercury emission inventory Australia is suggested to emit more than 102.5 tonnes Hg/yr from anthropogenic sources, which is 10 times more than that indicated by this study. This discrepancy arises by the use of inappropriate mercury emission factors, particularly for the combustion of Australian coals, in that estimation. [ABSTRACT FROM AUTHOR]

The article reports on the evaluation of various retail woodheater models conducted by New Zealand and Australia which aims to assess their impact towards air pollution in the two countries. The test was conducted on 47 woodheater models which focuses on their engineering design and labelling to assess how the models contribute to air pollution, including combustion, location of air inlets, and firebox dimensions. Both countries have also evaluated how the models meet the requirements set under the 4012 and 4013 Emission Standards. The audit reveals that most of the models failed to comply to the Standards, were different from their engineering drawings, and have incorrect labels. It states that the development of cleaner burning models will help reduce the emission problem.

Residential wood heaters are one of the most significant sources of urban air pollution in winter months across southern Australia; but compared to efforts to control transport and industrial emissions little has been done to control this source. In coming issues, John Todd will provide comment on wood heaters and wood-smoke starting with some background information about firewood combustion processes. [ABSTRACT FROM AUTHOR]