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The cigar wrapper, binder and filler play different roles in cigar puffing. This work aims to conduct a comprehensive study on the pyrolysis process of cigar wrappers, binders and fillers to obtain the similarities and differences in the residue, combustibility and pyrolysis products. In the residue section, the surface microstructure of the cigar wrapper, binder and filler was scanned by the scanning electron microscope, and the elemental state composition was characterized by X-ray photoelectron spectroscopy during the combustion process. The combustibility of the cigar wrapper, binder and filler was evaluated by the mass loss rate obtained from thermogravimetric experiments and the heat release rate obtained from the microscale combustion calorimeter experiments. The pyrolysis products were analyzed by infrared spectroscopy and mass spectrometry. The research results show that the similarities between wrapper, binder and filler lie in the elemental composition, combustibility and the main components of pyrolysis products. The difference lies in the fact that the surface microstructure of the wrapper is the smoothest, while the filler is the roughest with the leaf vein. The concentration of pyrolysis products in filler is significantly higher than in wrapper and binder after 400 °C. This work analyzed the similarities and differences in their pyrolysis behavior, providing a deeper understanding of cigar pyrolysis. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An effective type of polymer heat-insulating material (foams) based on reactive oligomers is casting epoxy foams with high technological and operational parameters. However, polyepoxide foams are highly flammable, which significantly restrains their application in the construction industry. The aim of this work was to develop effective methods for reducing the flammability of filling epoxy foams. In order to achieve the objective, the following objectives were addressed: determining the influence of the chemical nature and content of additive and reactive bromine- and phosphorus-containing compounds on the thermal stability, flammability and operational properties of filling epoxy foams, and the development of polyepoxy foams of reduced flammability with high-quality physical and mechanical characteristics. When estimating the flammability of epoxy foams, we used both state-approved methods and the methods described in scientific and technical literature. The thermal properties of epoxy foams were studied with the help of multimodular thermoanalytical complex DuPont-9900. The data on the influence of the apparent density of foams and oxygen concentration in the oxidant flow on the flame propagation speed on the horizontal surface of polyepoxy foams are presented. It was revealed that the chemical nature of amine hardeners does not affect the thermal stability and flammability of epoxy foams. It was established that phosphate plasticizers are ineffective flame retardants of foamed epoxy resin, and the chemical structure of additive organobromic flame retardants insignificantly affects their efficiency. It was shown that microencapsulated flame retardants are inferior in flame retardant efficiency to additive flame retardants. It was found that effective flame retardants for casting polyepoxy foams are phosphorus-containing oligoether methacrylate and epoxidized waste from the production of tetrabromodiphenylpropane. The results of this research will form the basis for the production of an experimental industrial batch of samples of pouring epoxy foams of reduced flammability. [ABSTRACT FROM AUTHOR]

Building façade elements should have aesthetically pleasing geometrical shapes made up of sustainable materials with energy-efficient designs. The low mass-to-high strength ratio of glass fiber–reinforced concrete (GFRC) has the potential to be adopted as a façade material and has been used in the manufacturing of façade elements. The workability of GFRC mixes is comparatively low; therefore, commercial polymer admixtures are used to improve it. The application of commercial polymers may reduce the fire resistance of GFRC mixes due to their easy combustibility. This study investigated the possible application of waste paint to completely replace commercial polymer admixtures in GFRC. It explored the optimum dosage of waste paint to achieve the required strength of a GFRC mix to be used as a façade material. First, characterization of the waste paint was carried out using its rheological properties and solid content, which were compared with commercially available polymer and paint. Subsequently, the effect of different dosages of waste paint (i.e., 0.5%, 1%, and 2% by mass) on the workability and mechanical properties of GFRC mixes (e.g., compressive and flexural strength) was evaluated. Water absorption and porosity were also evaluated. Finally, the combustibility of GFRC mixes with waste paint was evaluated to qualitatively assess fire performance when compared with polymer GFRC mixes. The experimental results demonstrated that the addition of waste paint to the GFRC mixes improved workability. Furthermore, the mixes with a waste paint dosage of less than 1% showed no significant variation in compressive strength compared with the commercial polymer mix. However, the mix with 1% waste paint enhanced flexural strength by 34% whereas a further increase in waste paint content was observed to reduce flexural capacity due to an increase in porosity. Finally, the fire performance of the mixes showed that waste paint is a noncombustible material and can be used as a potential substitute for polymer admixtures in façade applications. [ABSTRACT FROM AUTHOR]

Characterizing forest fuel properties in terms of their distribution and flammability behaviour offers useful information for effective fire management. Satellite images provide synoptic images capturing the vegetation state and their change including burn area loss, enabling stratification, and narrowing down the search for further investigation on ground or laboratory. The study investigated the flammability of various forest fuels including sal, teak, bamboo and grass species, by analysing different fuel variables such as moisture content (MC), volatile matter (VM), ash content (AC), fixed carbon (FC), higher heating value (HHV) and minimum ignition temperature (MIT), and exploring the intrinsic relationships between and among them. The teak wood showed low MC (5.08%), high VM (81.91%), low AC (1.1%), high HHV (19.93 MJ/kg), high CF (93.82) indicating high sustainability, combustibility and consumability characteristics. Teak indicated higher flammability characteristics compared to sal, while grass indicated higher sustainability and combustibility characteristics compared to bamboo. Overall woody species (sal and teak) indicated high ignitability and sustainability characteristics over grass and bamboo. Among the plant components, leaves indicated high ignitability, wood indicated high sustainability, combustibility and consumability, and barks indicated low flammability characteristics. This study registers a maiden and early attempt using satellite and laboratory-based analysis to characterize the flammability properties of dominant species of tropical dry forests in eastern India. [ABSTRACT FROM AUTHOR]

Whether noncombustible or combustible construction is used, the presence of combustible materials is likely to be used for various reasons, such as interior finishes, flooring, and insulation. Consequently, how regulations consider the degree of combustibility in their fire classifications will influence the level of fire safety provided in these buildings and the exchanges between all actors in the construction sector. In North America, the regulation of combustibility is primarily governed by surface flame spread assessed through the Steiner tunnel test. While there is a growing prevalence of calorimetric methods globally, their incorporation into North American building codes remains notably limited. Based on ISO 5660-1 cone calorimeter test results of twenty commercially available North American building materials, a comparative study was conducted between the Canadian flame spread classification and the classifications in Japan, New Zealand and the European Union (Euroclass). The tests and their limitations are described herein, as well as the conceptual frameworks. The results suggest that as materials' combustibility levels increase, the level of agreement between classifications decreases and remains binary. The choice between the material and system scales is crucial for determining the effective development and implementation of regulations. [ABSTRACT FROM AUTHOR]

Flammable litter such as Pinus koraiensis needle accumulation increases the risk of wildfire. In the event of a high-intensity fire, forest resources can be severely damaged. To reduce the occurrence of forest fires, it is important to reduce loads and modify structures. This study conducted 270 indoor degradation experiments to determine physicochemical properties of Pinus koraiensis during the combustion degradation process. Combustion degradation treatment variables were constructed with different durations, Trichoderma fungi, and doses. The results show that the physicochemical properties of flammable litter changed significantly after degradation, with a maximum degradation rate of 11. The degradation rate was affected by time and microbial agents, but there was no significant difference between different doses. Principal component analysis was used to determine overall combustibility, and it was found that a dose of 4 mL of Trichoderma harzianum had the best effect on degradation for 42 days, reducing combustibility by 203%. It was found that the 6ml composite mould had the best inhibitory effect on fire spread rate, reaching the lowest value. After 42 days, the flame intensity of 4 mL Trichoderma harzianum reached its lowest value of 57.17 kw/m, which represents a decrease of 54% compared to the initial value. Similarly, the flame's length reached its lowest value of 4.91 cm, which represents a decrease of 31% compared to the same period last year. The aim of this study is to establish the relationship between time, microbial agents, dosage, flammable physical and chemical properties, overall flammability, and potential fire behaviour. The values of the goodness-of-fit index and the comparative fit index are both >0.98, and the values of the standardised root mean square residual and the approximate root mean square error are both <0.05. This study has a positive effect on accelerating the decomposition of combustibles, reducing the content of flammable components, reducing flammability and potential fire behaviour, and reducing the risk of forest fires. It is of great significance for strengthening natural resource management and forest ecological conservation. [ABSTRACT FROM AUTHOR]

Studying the combustibility and physical‒mechanical properties of wood is important for recommending its use in construction. The objective of this study was to evaluate the combustibility, as well as the physical and mechanical properties, of twelve Brazilian Amazonian woods. Species. For each species, the combustibility parameters, fire exposure test, residual mass, loss mass, intact mass, charred area, proximate analysis, basic density, compressive strength and modulus of elasticity were determined. All the evaluated properties were significant affected by the wood species. In the fire exposure test, ignition time ranged from 21 s to 55 s while flame time was between 108 s and 233 s. Residual mass ranged from 60,7% to 82,7%, and intact areas ranged from 28,13 % to 62,68 %. Basic density values ranged from 335 kg/m3 to 889 kg/m3, compressive strength ranged from 29 MPa to 82 MPa, and the modulus of elasticity ranged from 9 GPa to 33 GPa. The wood of Hymenaea courbaril (courbaril), Manilkara huberi (masaranduba), Handroanthus serratifolius (yellow lapacho) was identified as the most suitable for structural components, ensuring greater safety against possible fires. Short-term fire exposure tests, particularly the ignition time parameter combined with residual mass and intact area, are key for assessing wood resistence to fires.

Due to the intensive industrial development of the territory of Krasnoyarsk Krai, significant changes have taken place in the vegetation cover and the number of fire sources has increased. Due to climate change, the number of lightning discharges, which are the main cause of forest fires in the underdeveloped northern territories of the region, has also increased. The development of a regional fire hazard scale for weather conditions is caused by the fact that the existing unified federal fire hazard scale for weather conditions does not accurately characterize the fire hazard of forest areas in the region and does not allow rationally regulating the work of forest fire services and forestry. On the basis of data on the number and area of forest fires and the causes of their occurrence, generalizations and analysis of the timing of fires and the causes of fires in the forest areas of Krasnoyarsk Krai were performed. It is revealed, that in modern conditions the area of the region is characterized by an increase in fire activity. Due to the complexity of the relief, the diversity of climatic and forest conditions for each forest area, we have constructed regional fire hazard scales for weather conditions and compared them with the unified federal scale. The use of fire hazard scales developed by us for the forest areas of the Krasnoyarsk Krai will allow timely detection and extinguishing of forest fires and, consequently, reduce damage from forest fires.

Motivation: The propensity of plant tissues to burn (i.e. their flammability) is a key trait to understand fire regimes in many ecosystems across the globe. Measuring plant flammability under laboratory conditions allows us to improve both our understanding of plant evolutionary processes and modelling tools for simulating fire hazard and behaviour. Plant flammability has been studied from different but complementary disciplines (e.g. physics, chemistry, ecology, evolution, forestry). However, information is scattered and standardized terminology is lacking, which slows down the progress of research on plant flammability. Here we provide an open access global database on plant flammability traits measured under laboratory conditions aiming to: (a) identify the diversity of methodologies to measure plant flammability under laboratory conditions; (b) standardize the associated terminology; and (c) find geographical, ecological, and taxonomic gaps in our knowledge on plant flammability. We hope this database will stimulate transdisciplinary research and provide useful information to better cope with an increasingly flammable planet. Main Types of Variables Contained: The FLAMITS database contains 19,972 records of 40 flammability variables (classified according to the measured component of flammability). For each record, relevant details of the flammability experiment are given, such as the burning device, the ignition source, and the burnt plant part. In addition, FLAMITS compiles taxonomic and functional data of the studied species and information on the study site (i.e. locality, geographic coordinates, biome, biogeographic realm, and fire activity). Spatial Location and Grain: We compiled data from 295 studies in 39 countries and distributed across 12 biomes worldwide. Time Period and Grain: The last 62.5 years (1961 to 15th May 2023). Major Taxa and Level of Measurement: 1790 plant taxa from 186 families, 883 genera, and 1784 species. Software Format: Five text files (.csv), relationally linked. [ABSTRACT FROM AUTHOR]

The ever-increasing volumes of food waste generated and the associated environmental issues require the development of new processing methods for these difficult waste streams. One of the technologies that can treat these waste streams directly is hydrothermal carbonization. In this work, olive pomace and orange peels were treated via a mild hydrothermal carbonization process (TORWASH®) in a continuous-flow pilot plant. For olive pomace, a solid yield of 46 wt% and a dry matter content of 58% for the solid press cakes were obtained during continuous operation for 18 days. For orange peels, the values were lower with 31 wt% solid yield and a 42% dry matter content during 28 days of continuous operation. These values corresponded fully with initial laboratory-scale batch experiments, showing the successful transformation from batch to continuous processing. The obtained hydrochar from both feedstocks showed an increase in higher heating value (HHV) and a significant reduction in ash content. Pellets produced from the solids met the requirements for industrial use, demonstrating a large increase in the deformation temperature and a significant reduction in the potassium and chlorine content compared to the original feedstock. These results indicate the excellent potential of these pellets for combustion applications. [ABSTRACT FROM AUTHOR]

Background and basics for the application of fire protective coverings in timber construction This article summarises the current knowledge in the application of fire protective coverings for timber constructions. The different types of fire protective coverings, their definitions in standards and building codes and their performance requirements are discussed and the associated differences are compared. From the discussion of the backgrounds, an expanded view of the criteria to be verified for fire protective coverings for timber members is developed, which enables an optimised and resource‐saving application while maintaining the requested safety level in fire protection. [ABSTRACT FROM AUTHOR]

High-impact mega-fires in many temperate forests and shrublands of the world have called for pre-emptive approaches to mitigate fire risk. Comparative appraisals of the characteristics and flammability of plant fuels can inform fire risk predictions and vegetation management efforts in the wildland–urban interface of such fire-prone regions. Prompted by recent extreme fires in the Cape Floristic Region of South Africa, we assessed the flammability and fuel traits of excised terminal branches of 30 woody species (many of which have never been studied before) that commonly occur as native, alien or invasive species in this region and some other temperate regions of the world. We furthermore assessed changes in flammability and fuel moisture in these species after partial drying of excised branches under ambient conditions for 2–4 weeks to simulate extreme drought conditions. Several prominent alien invasive taxa in the study region and elsewhere showed high flammability, namely Pinus radiata (median flammability index score of 2.5), Eucalyptus camaldulensis (2.3), Acacia mearnsii (2.2), Acacia melanoxylon (2.2), Pinus pinaster (2.2), Acacia cyclops (2.0) and Cestrum laevigatum (2.0). The high fire risk posed by these species needs to be considered in potential further plantings and in invasive plant clearing efforts. Conversely, Osteospermum moniliferum (median flammability index score 0.9) and Acacia saligna (1.3) are species with large invasive ranges that showed low flammability, which may suppress fire regimes in fire-prone ecosystems but present suitable options for fire mitigation in their native ranges. Fynbos and thicket species native to the study region mostly displayed high and low flammability, respectively. Species of which the flammability is likely to increase disproportionately under extreme drought conditions include select fynbos and thicket species, and among the alien invasives, all four Acacia species, Leptospermum laevigatum, Callistemon viminalis, Pinus pinaster and Osteospermum moniliferum. Management of these species should be a secondary priority (after high flammability species) in the wildland–urban interface and other high fire risk areas.

Under high temperatures, fiber-reinforced polymers are destroyed, releasing heat, smoke, and harmful volatile substances. Therefore, composite structural elements must have sufficient fire resistance to meet the requirements established by building codes and regulations. Fire resistance of composite materials can be improved by using mineral fillers as flame-retardant additives in resin compositions. This article analyzes the effect of fire-retardant additives on mechanical properties and fire behavior of pultruded composite profiles. Five resin mixtures based on vinyl ester epoxy and on brominated vinyl ester epoxy modified with alumina trihydrate and triphenyl phosphate were prepared for pultrusion of strip profiles of 150 mm × 3.5 mm. A series of tests have been conducted to determine mechanical properties (tensile, flexural, compression, and interlaminar shear) and fire behavior (ignitability, flammability, combustibility, toxicity, smoke generation, and flame spread) of composites. It was found that additives impair mechanical properties of materials, as they the take place of reinforcing fibers and reduce the volume fraction of reinforcing fibers. Profiles based on non-brominated vinyl ester epoxy have higher tensile, compressive, and flexural properties than those based on brominated vinyl ester epoxy by 7%, 30%, and 36%, respectively. Profiles based on non-brominated epoxy resin emit less smoke compared to those based on brominated epoxy resin. Brominated epoxy-based profiles have a flue gas temperature which is seven times lower compared to those based on the non-brominated epoxy. Mineral fillers retard the spread of flame over the composite material surface by as much as 4 times and reduce smoke generation by 30%. [ABSTRACT FROM AUTHOR]

Background. Mitigation of wildfires at the wildland-urban interface (WUI) will be enhanced by understanding the flammability of plants growing in this zone. Aims. We aimed to: (1) compare shoot flammability among wildland native, and both urban native and urban exotic ornamental plants; (2) quantify relationships between shoot traits and flammability; and (3) establish flammability scores to distinguish low-from high-flammability species. Methods. Flammability and traits of field-collected shoots were measured and relationships quantified in 44 species from the Blue Mountains World Heritage Area, Australia. Key results. In our study area, urban exotic plants were less flammable than wildland and urban native plants. Slow-igniting shoots had high fuel moisture and bulk density; short-burning shoots had low bulk density and volume; shoots recording low maximum temperatures had high fuel moisture, low bulk density and volume; and shoots with low biomass consumed in flames had high fuel moisture and low volume. Our novel flammability scores distinguished low-flammability (e.g. Lophostemon confertus) from high-flammability native species (e.g. Callistemon citrinus). Conclusions and implications. Low-flammability plantings at the WUI should preferably use native species given potential ecological impacts of exotics. We suggest that future work should seek to identify broader suites of low-flammability native species. [ABSTRACT FROM AUTHOR]

Comparative data about the combustibility of adhesives of different chemical compositions are presented. The application of epoxy oligomers with chlorine or bromine atoms is considered for producing materials with enhanced fire-safety properties. The potential of adding phosphazenes with epoxy groups to adhesives with enhanced fire-safety properties is shown, as well as combinations of various types of materials for reducing polymer combustibility. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the feasibility indicators of the injection of coke breeze for blast furnaces (BFs) were tested. Experiments were conducted on the combustion behavior of coke breeze at different particle sizes, and the effects of ratio of coke breeze in pulverized coal on the combustion performance of blends were studied. On the basis of the above experiments, industrial tests involving injecting coke breeze after milling were carried out in 3# BF of Shougang Jingtang. The results show that most of the coke breeze particle sizes were distributed above 1 mm. The grindability and combustion performance are poor, so the material needs to be ground before mixing with pulverized coal. The best combustibility can be obtained by using a particle size of less than 8.74 μm of coke breeze in the injection. With the increase in the coke breeze ratio, the combustion performance of blended coal worsened; the negative effects of coke breeze can be improved by increasing the proportion of bituminous coal. According to the results of industrial tests, 8% coke breeze in blends had no negative effect on the smelting state, and the output of the BF increased slightly. Industrial tests proved that coke breeze can partly replace anthracite for BF injecting, which reduced the cost of hot metal while realizing the high value-added resource utilization of coke breeze. [ABSTRACT FROM AUTHOR]

• The applicability of pulverized high volatile coal in ironmaking PCI was evaluated. • As the amount of agglomeration increases, unburned carbon increases. • Agglomeration occurs between coals due to tar the devolatilization process. • When agglomeration occurs, the specific surface area structurally decreases. • Tar plays bridging role within devolatilization agglomeration process. Large-scale (volume > 2000 m3) blast furnaces (BFs) requiring expensive, high-grade coal are currently used in the iron and steel industry. High-volatile coal (HVC) must provide a substitute for high-grade coal to facilitate economical operations. This study determines the applicability of HVC and thermal coal within the fine particle extraction (FINEX) and conventional BF steelmaking processes using a drop-tube furnace. Furthermore, the characteristics of single- and blending-coal-carbon conversions are analyzed using unburned carbon (UBC). In the BF, an increase in agglomeration leads to an increase in UBC, where approximately 20 % agglomeration can be achieved. However, under FINEX conditions, due to the high oxygen concentration approximately 50 % agglomeration can be achieved. To determine the principle of the agglomeration phenomenon, a chemical-percolation-devolatilization model is used to analyze the amount of tar, light gas, and char generated during the devolatilization process. Using HVC achieves 89.7 % agglomeration which generates a 30 % tar volume during devolatilization. Tar has a significant effect on agglomeration and facilitates bridging, causing agglomeration into a large particle as identified from the structural agglomeration of a scanning electron microscopy image. This phenomenon affects raceway formation and the combustion stability of pulverized coal injections. [ABSTRACT FROM AUTHOR]

This work describes the test methods used in the United States and in Western Europe for regulatory assessments of whether a material can be considered to be a noncombustible material for use in building construction. It also provides the history of the development of such test methods, which is essential for understanding their use in regulation. The work distinguishes between the absolute concept of noncombustibility and the use of the concept in actual practice, for building construction. A key aspect of the work is that it describes both the origin of the pass/fail criteria associated with the test methods in use and their application. The work also describes the type of requirement that is being associated, in codes and regulations, with materials (which are designated limited combustible materials by the National Fire Protection Association (NFPA) and as A2 materials by the European Union) that provide "no significant" contribution to fire hazard. Such materials are often permitted for use in applications where otherwise only noncombustible materials are permitted. The work discusses other proposed methods for assessing noncombustibility, mainly based on heat release, which, although technically sound, have not become adopted for regulation in either the US or Western Europe. The work also discusses pass/fail criteria associated with the major noncombustibility tests, namely those associated with ASTM E136 (in the US) and ISO 1182 (in Western Europe and the maritime world) and the rationale for such criteria. [ABSTRACT FROM AUTHOR]

This article focuses on the predicament of owner-occupiers and small investors presently liable for the removal of combustible cladding on build-to-sell residential high-rise. We argue that while the proliferation of combustible materials has been shaped by cost-cutting and risk-shifting by construction firms, these practices did not on their own transfer the responsibility of remediation to consumers. Examining the attempts of one densifying nation, Australia, to locate responsibility for combustible cladding through two parliamentary inquiries, we analyse witness testimonies to show how public policies encouraged materials substitution, removed on-site inspection and protected corporations from litigation. Moving beyond neoliberalism, these policy reforms leveraged information asymmetries and the material complexity of residential high-rise to create a climate of "imperceptibility" towards unsafe materials. Together, material, financial and policy dimensions intersected to enable capital accumulation through the expansion of consumer harm in high-rise housing markets. We conclude that construction materials and processes are an overlooked, yet critical domain of governance in financialised housing regimes. [ABSTRACT FROM AUTHOR]

Abstract—This article presents the results of technological, physicomechanical, and fire-resistant tests of polyester resins, binders, and fiberglass on their basis produced by contact molding. The obtained results are compared with those of fiberglass used at present in shipbuilding. [ABSTRACT FROM AUTHOR]

One of the most important priorities for all countries with property beyond the Arctic Circle and territories located in permafrost areas is the development of special construction technologies and systems. The required conditions are met by insulation systems based on seamless insulation shells made of polyethylene foam. The study of the strength and performance properties of polyethylene foam and its combinability was carried out according to standard methods and using the methods of experimental design and the analytical processing of the results. The change in material properties at negative temperatures was determined based on the results of climatic tests, followed by an evaluation of creep under load. The evaluation of the effectiveness of the design solutions was carried out using special computer programs. It was found that the performance characteristics of products made of polyethylene foam (rolls, mats) meet the requirements for insulation materials used at temperatures down to −60 °C. The resulting material is moderately combustible, which must be taken into account when developing recommendations for its use in insulation systems. A nomogram has been developed that makes it possible to predict the properties of a material and solve formulation problems. Insulation systems were developed, and a visualisation of the thermal fields of the insulation systems of the external walls and ceilings of a building was carried out. [ABSTRACT FROM AUTHOR]

This paper investigates aluminium composite panels (ACPs) to understand the fire behaviour of combustible cladding systems under different fire scenarios. A fire dynamics simulator (FDS) is used to develop the numerical model of full-scale fire tests of combustible cladding systems using the procedures of the British BS 8414.1 standards. The results obtained from the FDS models are verified with test data. Seven test scenarios are investigated with four distinct parameters, i.e., cavity barrier, air-cavity gap, panel mounting (with and without joining gaps between the panels), and material combustibility qualities. A critical air-cavity gap (50–100 mm) is established at which maximum fire spread is noticed. Furthermore, variations in the cavity barrier, panel mounting, and material combustibility significantly impact the rapid fire spread of ACP cladding systems and the internal failure criterion. The results from the present study can serve as a basis for future research on the full-scale fire-test development of combustible ACPs. [ABSTRACT FROM AUTHOR]

In June 2017, extreme fires along the southern Cape coast of South Africa burnt native fynbos and thicket vegetation and caused extensive damage to plantations and residential properties. Invasive alien plants (IAPs) occur commonly in the area and were thought to have changed the behaviour of these fires through their modification of fuel properties relative to that of native vegetation. This study experimentally compared various measures of flammability across groups of native and alien invasive shrub species in relation to their fuel traits. Live plant shoots of 30 species (10 species each of native fynbos, native thicket, and IAPs) were sampled to measure live fuel moisture, dry biomass, fuel bed porosity and the proportions of fine-, coarseand dead fuels. These shoots were burnt experimentally, and flammability measured in terms of maximum temperature (combustibility), completeness of burn (consumability), and time-to-ignition (ignitability). Multiple regression models were used to assess the relationships between flammability responses and fuel traits, while the Kruskal-Wallis H test was used to establish if differences existed in flammability measures and fuel traits among the vegetation groups. Dry biomass significantly enhanced, while live fuel moisture significantly reduced, maximum temperature, whereas the proportion of fine fuels significantly increased completeness of burn. Unlike other similar studies, the proportion of dead fuels and fuel bed porosity were not retained by any of the models to account for variation in flammability. Species of fynbos and IAPs generally exhibited greater flammability in the form of higher completeness of burn and more rapid ignition than species of thicket. Little distinction in flammability and fuel traits could be made between species of fynbos and IAPs, except that fynbos species had a greater proportion of fine fuels. Thicket species had higher proportions of coarse fuels and greater dry biomass (~fuel loading) than species of fynbos and IAPs. Live fuel moisture did not differ among the vegetation groups, contrary to the literature often ascribing variation in flammability to fuel moisture differences. The fuel traits investigated only explained 21-53% of the variation in flammability and large variation was evident among species within vegetation groups suggesting that species-specific and in situ community-level investigations are warranted, particularly in regard fuel moisture and chemical contents. [ABSTRACT FROM AUTHOR]

Leaf flammability is a functional trait that can vary widely among plant species. At present, however, the effects that increasing radiant heat flux have on variation in leaf flammability among species are not well understood. Yet, such effects could have important implications for wildfire models that take into account species' differences in flammability.We examined how five leaf flammability attributes spanning ignitibility (times to incandescence and flaming), sustainability (incandescence and flame durations) and combustibility (proportion of leaves entering flaming combustion) responded to increasing radiant heat fluxes (29.6 to 96.6 kWm−2) in 10 species of fire‐prone woodlands.As radiant heat flux increased, times to incandescence and flaming became significantly faster and proportions of leaves entering flaming combustion became significantly higher. In contrast, incandescence duration became significantly shorter at high radiant heat flux. Differences among species in these flammability attributes decreased with increasing radiant heat flux, with species becoming significantly more similar to each other. Differences among species in flame duration, however, were not significantly affected by increasing radiant heat flux, with leaf flaming durations in each species remaining relatively fixed across the radiant heat flux gradient.Our findings show that leaf flammability is significantly affected by increasing radiant heat flux. We suggest that of the flammability attributes assessed in our study, flame duration is the most informative to include in wildfire models which explicitly consider species' flammability, given that differences among species in flame duration are maintained across a radiant heat flux gradient. [ABSTRACT FROM AUTHOR]

Summary: A cone calorimeter, a standard device to measure the fire reaction properties of materials, is modified in this study to investigate its potential to replace the cylindrical furnace test method to assess the combustibility of cladding materials used in buildings. The modification allows cladding materials to be evaluated under conditions closer to their end‐use configuration than the current testing condition in the cylindrical furnace test. In addition, the modified cone calorimeter method provides more quantitative data on the fire reaction properties of the cladding materials compared to the passed/failed indicator in the cylindrical furnace test. Comparative studies between modified cone calorimeter and cylindrical furnace test results for four types of cladding with different combustibility properties are performed. The surface temperature, time‐to‐ignition, and flaming duration values measured for the claddings using the two test methods are similar, leading to the same classification based on AS 1530.1 standard. Other fire reaction properties of the claddings can be measured using the modified cone calorimeter method, which is not possible with the cylindrical furnace test, including mass loss rate, heat release rate, and smoke production, which are particularly dependent on the formation of a ceramic‐like carbonaceous layer of tested samples. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polyvinyl chloride (PVC) is one of the mostly plasticized polymers. The plasticizers used in this case are esters of aromatic or aliphatic acids with linear or branched aliphatic alcohols with a moderate chain length. Among them, phthalates (orthophthalic acid esters with fatty alcohols) have the widest range of applications among aromatic acid esters. They are characterized by excellent compatibility not only with PVC, but also with a number of other polymers, possess good physical and mechanical properties, but are toxic compounds. Therefore, their use is gradually being replaced by low-toxic and non-toxic plasticizers. Adipic acid esters which are widely used are environmentally safe. However, their use in plastic compounds for cable products requires the introduction of special additives – flame retardants.

Polyvinylchloride (PVC) is the most frequently used polymer for obtaining a wide range of materials for various purposes. The main advantages of the polymer – excellent thermal and electrical insulation properties, high resistance to various aggressive substances, namely: acids, alkalis, various lubricants; lack of taste, smell; low water absorption (0.4–0.6%). The possibility to obtain PVC-plasticates with different characteristics is provided by the introduction of various additives, the bulk of which are plasticizers. Plasticizers based on adipic acid esters give a number of valuable properties to PVC-based compositions. However, the use of plasticizers affects the resistance of compounds to the combustion, therefore, the substances which eliminate this disadvantage are added in the polymer composition.

The common evergreen broad-leaved tree species in central Yunnan, Acacia dealbata, Eucalyptus globulus, and Cyclobalanopsis glaucoides, were studied to explore the relationship among soil available phosphorus content, the physicochemical properties, combustibility of plants leaves in central Yunnan. With an increase in the soil available phosphorus content, the proportion of sample hatches with an increase in crude fat content, a decrease in ash content and an increase in calorific value were calculated. The comprehensive index of plant leaf combustibility was calculated, and the influence of soil available phosphorus content on plant combustibility was studied by analyzing the relationship between the comprehensive index of leaf combustibility and soil available phosphorus content. The results showed that with an increase of soil available phosphorus content, the proportion of hatches with increased crude fat content, decreased ash content, and increased calorific value in A. dealbata and C. glaucoides leaves rose above 50%. However, in E. globulus leaves, the proportion of hatches with decreased ash content and increased calorific value did not reach in 50%, although the proportion of hatches with increased crude fat content exceeded 50%. The increase in soil available phosphorus content in the three tree species resulted in increased crude fat content, hut the effects on ash content and calorific value differed among the tree species. This effect can increase the combustibility of plant leaves, especially for those of C. glaucoides. [ABSTRACT FROM AUTHOR]

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Mathematical models appear as very attractive alternatives in blast furnace studies. Therefore, a three-dimensional model is described and validated to simulate the flow and combustion of binary coal blends under simplified blast furnace conditions. The present article aims to analyse the performance of different coals and their blends for conventional and coaxial oxygen enrichment methods. Among the simulated coals, Coal C, which combines one of the smallest particle sizes with one of the highest volatile matter contents, presented the highest burnout and average temperature values. Coaxial oxygen enrichment showed a negative effect on coal combustibility in the cases with 26.9% of O2. This is explained by the large amount of gas being injected by the coaxial lance, resulting in a cooling effect and particle concentration. Also, blending coal A with coal B resulted in an improvement of burnout for both coals, because of the synergetic effect caused by their combustion. [ABSTRACT FROM AUTHOR]

In this research, flame retardant polymer-nanocomposites with polyester fibers and inorganic nano materials were prepared to investigate the reduction of flammability. Nano calcium tetraborate (CaB4O7) and Nano barium tetraborate (BaB4O7) were synthesized by precipitation method onto polyester fibers to achieve flame retardant fiber nanocomposite. The prepared fiber nanocomposites were characterized by several techniques such as x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), fourier transform infrared spectroscopy (FT-IR), vertical flammability test, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The CaB4O7 and BaB4O7 with less than 100 nm in size, was found to be well-dispersed throughout the matrix without the formation of large aggregates which is showed efficient flame-retardancy properties. The optimum values for donation of flame-retardancy were obtained 8.02 and 9.5% for calcium tetra borate and barium tetra borate, respectively. TGA/DTG and DSC analysis of pure, treated fibers was accomplished and their thermograms were compared and commented. The results show that the flame retardancy mechanism of obtained flame retardant coated fiber is a condensed-phase phenomenon due to the formation of a protective char layer that acts as a mass transport barrier and a thermal insulator.

The article considers approaches and requirements for definition of fire safety characteristics of polymer composite materials (PCM) in shipbuilding. The results of experimental determination for such characteristics for three-layer polymer composite material and fiberglass layer as an example are provided. The need for the development of domestic regulatory documentation on the correct requirements for testing multilayer PCM and data interpretation has been identified. [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]

Purpose. To obtain the flame retardants polymer compositions for cables tested the effect of use EVA compositions with magnesium hydroxide, on indicators combustibility polymer. Methodology. We used the method of differential scanning calorimetry and defined heat flux dependence on the test time for each composition at temperatures from 20 °C to 600 °C rate of temperature rise: 50 °C/min, 75 °C/min, 100 °C/min. Using the model of free kinetics we determined dependence of the activation energy from the conversion, a dependence of the conversion on the time of the test, the dependence of the time of the conversion from the temperature for each concentration. To comparison of these parameters for each composition we plotted the dependence of the time of the conversion from the temperature and the dependence the degree of conversion from the time of temperature exposure during the combustion of each of the compositions. Results. We obtained the kinetic characteristics, allowing to determine the composition, which provided the best results to reducing the kinetic parameters of flammability of polymeric compositions. Originality. For the first time we used the DSC and model-free kinetics to determine the effect properties of ingredients of the polymer compositions on the combustibility performance. Practical use. The research results can be used to develop polymer compositions for cable products.

The standard method of determining the reactivity CRI and postreactive strength CSR of coke is analyzed. Its practical applicability to blast-furnace processes is discussed. Modifications are proposed so as to optimize the standards regarding the determination of CRI and CSR. It would be expedient to study the characteristics of coke more thoroughly so as to better understand its behavior in the blast furnace. [ABSTRACT FROM AUTHOR]

During the utilization of coal in large power plants, one of the major logistical issues is related to spontaneous ignition of the coal. This characteristic of coal depends on the rank and type of the coal, the content of the moisture and volatile matter as well as particle size distribution. This paper presents the novel approach for determination of spontaneous ignition potential of the coal developed as the internal laboratory experimental method. The experimental tests were performed by thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) of tested samples at five different heating rates: 3, 5, 7, 10 and 20 K min−1 under an air atmosphere. The TGA results were used for determination of tangent slope of the mass loss rate curves in the zone of the release of volatiles at considered heating rates for all coal samples. The linear interpolation of the data obtained by performed tangent slope analysis and heating rates provides the straight line unique for each tested sample. According to the standard method, the slope of the obtained straight line is defined as thermogravimetric index of spontaneous ignition (TG spi). In addition, a new formula for determination of TG spi index was provided. Three different coal samples were analyzed and classified according to the spontaneous ignition potential, based on the obtained values for TG spi by standard procedure and also using a newly proposed method. By varying the gradient of linear dependence of self-heating coefficient against reference temperatures (T ref,i), the mass and heat transfer limitations for different coals were discussed. [ABSTRACT FROM AUTHOR]

Recently, standard fire resistance testing has been questioned for combustible products. A part of the comments address the thermal boundary conditions and the different thermal exposure of combustible products in comparison to incombustibles. These comments are evaluated in this technical note. To compare heat flux measurements of combustibles and incombustible products when tested in a furnace, furnace tests were performed. The furnace was controlled by plate thermometers to follow the EN 1363/ISO 834 standard temperature-time curve. It could be proven that (a) the heat flux measurements at the specimens surface behind the plate thermometer (PT) are not higher than in front of the PT. The reason for this is most likely that no flaming combustion is possible near the surface due to the low oxygen content typically for a furnace. It could be further shown (b) that the heat flux measurements when combustibles are tested follow the trend reported in literature for incombustibles. Further, (c) that the lower burner fuel used in furnaces is due to the contribution of the specimen (ca. 30% in the presented tests) and due to the lower thermal inertia (ca. 20% in the presented tests). Finally it can be concluded that the thermal exposure of combustibles and incombustibles is equivalent in furnaces simulating a ventilation controlled fire development for a pre-defined duration. • The thermal exposure of combustible and non-combustible products are equal when tested in fire resistance tests. • The lower fuel consumption when combustibles are tested is due to the test specimen's contribution and lower thermal inertia. • There is no significant flaming at the surface of a combustible product when tested in an environment as in a furnace test. [ABSTRACT FROM AUTHOR]

Abstract Pyrolytic chars are a potential high-quality fuel for use in iron ore sintering and pulverized coal injection (PCI) operations of blast furnace. In this study, industrial char produced from a moving-bed pyrolyzer was screened into four particle size ranges and compared with coke used in an industrial sintering process and a PCI coal used in an industrial blast furnace, and their basic compositions, micropore structures, functional group distributions, carbonaceous structures, reactivities, and gas release behaviors during combustion were analyzed. Furthermore, the mechanism underlying the particle size-dependent properties of the char was analyzed by comparing it with a char prepared under laboratory-simulation conditions. Results demonstrate that char particles larger and smaller than 3 mm (the turning point) have different structures and properties. More specifically, particles larger than 3 mm have stable properties, better developed pore structures, carbonaceous structures that are more ordered, superior reactivities, and lower releases of SO 2 and NO x. Therefore, they represent a desirable option for use in fueling sintering and PCI operations. Char particles smaller than 3 mm were further investigated by screening them into particle size ranges, and results showed that they had significantly varied compositions and structures, which further confirmed their unsuitability for use in the two operations. Finally, the particle-size-dependent properties of the char can be explained by the differing residence times, the radial variations in pyrolysis degrees, and the mechanical (or thermal) stresses experienced by the different raw coal particles within the pyrolyzer. Highlights • Char particles larger than 3 mm meet the requirements. • Char releases less gaseous pollutants during combustion. • The size-dependent properties are explained. [ABSTRACT FROM AUTHOR]

In this study, a combustion study of tire pyrolytic carbon black (CBp), gas coal (GC), and their blends was carried out by thermogravimetric analysis with four heating rates under air atmosphere. And the structure characteristics of CBp and GC were studied using particle size distribution, scanning electron microscope, X-ray diffraction, Raman spectra followed by peak deconvolution and data analysis. The results demonstrated that the structural differences between CBp and GC directly affected their thermal behavior trends. GC with low graphitization degree had more combustibility reactivity than that of CBp, while the mean reaction rate and maximum reaction rate of CBp were larger than GC due to its bigger specific surface area and higher porosity. For blends, the combustibility reactivity could be improved by blending with GC, and there was obviously synergetic effect for the co-combustion of CBp and GC. The combustion reaction mechanisms and kinetic parameters were carried out using three non-isothermal kinetic models: random nucleation nuclei growth model (RNGM), volume reaction model, and unreacted core model. The kinetic analysis demonstrated that the RNGM model had a better performance than other models for describing the thermal behavior of the selected samples. In addition, the synergetic effect between CBp and GC was observed from the kinetics data calculated by RNGM. The activation energies of CBp and GC calculated by RNGM model were 119.6 kJ mol−1 and 126.4 kJ mol−1, respectively, whereas the lowest activation energy for their blends was 104.3 kJ mol−1 when CBp ratio was 40%. [ABSTRACT FROM AUTHOR]

One of the perspective types of water-based fuels is the foamed emulsion. Foamed emulsion represents the foam consisting of oxygen bubbles distributed in the oil-in-water emulsion. Paper considers experimentally the issues of combustion of foamed emulsion with the high content of water fraction. For the first time, the synchronized data on the flame speed and the pressure profile along the channel length are obtained. It is shown that flame acceleration in the foam is possibly related to the explosive boiling of the liquid phase of the foam that is accompanied by a formation of weak compression waves. The interaction between these compression waves and the flame front leads to the change in the total burning rate of the foam. The data on the average diameter of water droplets are obtained via photography of multiphase flow of combustion products. It is shown that the average diameter of water droplets decreases with the increase in the flame speed. The conditions required for the combustion of the foamed emulsion with high water content are analyzed. It is shown that the foamed emulsion becomes incombustible with the decrease in oil volatility. [ABSTRACT FROM AUTHOR]

Charcoal is a very important reducing agent in Brazil, the world’s largest steel industry based on charcoal blast furnace. Charcoal generates large amounts of charcoal fines during its production and processing. A good alternative for harnessing this fuel is the injection into coke-based blast furnaces via PCI process (Pulverized Coal Injection), a key technology for reducing use of coke in ironmaking. This study aimed to evaluate the combustibility and reactivity to CO2 of binary blends of charcoal fines and coals with purpose to PCI. Moreover, it was also attempted to identify the reasons for the different behavior of coals. The work was carried out by thermogravimetric analysis (TGA). The proportions of charcoal used were 10, 20 and 50% in mass. Charcoal showed the highest combustibility and reactivity among tested fuels and the blends formulated had higher combustibility and reactivity than single coals.

With recent and predicted increases in the frequency and intensity of wildfires, there is a pressing need for mitigation strategies to reduce the impacts of wildfires on human lives, infrastructure and biodiversity. One strategy involves the use of low-flammability plants to build green firebreaks at the wildland–urban interface. It is common, however, to encounter uncertainty in a diverse range of stakeholders about the concept of flammability as it applies to plants, which may impede efforts to identify suitable low-flammability plant species. Here, we provide an approach to identify low-flammability plant species that integrates three fundamental and relatively easy-to-measure plant-flammability attributes – ignitibility, sustainability and combustibility – in a way that removes confusion about the concept of plant flammability. These three intrinsic flammability attributes relate to each other such that an ideal low-flammability species is one that is slow to ignite, sustains burning for a short period of time and combusts with low intensity. Consideration is then given to secondary attributes of plants critical to the selection of low-flammability plants, including attributes that influence the volume of fuel available for fires and the vertical and horizontal spread of fires. More work is urgently needed across the world to identify low-flammability plant species using standardised measurement protocols, and our integrated approach provides a transparent way to ensure we are selecting the right species, for the right location, in green firebreaks.

Highlights • Chemical-structural properties of coal, biomass char were investigated by using Raman. • The combustion characteristics of coal, biomass char and plastic were studied. • The correlation between structure characteristics and its combustion were obtained. • A TRNGM model was used to calculate the combustion process of plastic. Abstract In this paper, thermal analysis method (TGA) was adopted to describe the combustion behavior of bituminous coal(GC), anthracite(LC), biomass(PS) and plastic(PVC).The structure characteristics of these samples were carried out using Raman spectroscope followed by peak deconvolution and data analysis. The kinetic parameters and combustion reaction mechanism were obtained by fitting experimental data with the random nucleation nuclei growth model (RNGM) and volume model (VM) in order to find out the kinetics characteristics responsible for the combustion of the samples. The results indicate that significant difference between combustion process of these samples are mainly attributed to their differences structures, the combustion reactivity of PS is better than GC duo to the catalysis of alkali matter in biomass ash. RNGM model is better than VM model for simulating the combustion process, and TRNGM model plays a good performance in depicting the combustion process of PVC with three reaction stages. [ABSTRACT FROM AUTHOR]

The synergism between nanoparticles and different kinds of halogen‐free fire retardants leading to reduction in flammability and smoke generation of polyethylene was investigated. The composites were evaluated by thermogravimetric analysis, oxygen index test, cone calorimeter measurements, and a single‐chamber test. Moreover, the semivolatile and volatile compounds evolved in the thermal degradation processes of polyethylene were determined using a steady state tube furnace and gas chromatograph with mass spectrometer. Morphological and structural characteristics as well as thermomechanical properties of the composites were characterized using various techniques including scanning electron microscopy (SEM), X‐ray diffraction (XRD), and dynamic mechanical thermal analysis (DMTA). The obtained data were compared to the results received for polyethylene and polymer with bromine‐containing fire retardants. The incorporation of nanofillers and halogen‐free fire retardants caused a reduction in combustibility as a consequence of the formation of char. Furthermore, the presence of nanoparticles has a beneficial effect on the inhibition of dripping. The polyethylene with carbon nanotubes, zinc borate, and aluminum hydroxide exhibited better combined properties of fire behavior and production of nontoxic smoke compared to the remaining composition and reference materials. [ABSTRACT FROM AUTHOR]