Gravimetric Yield In Charcoal Research Articles

Clarifying the carbonization temperature effects on the production and apparent density of charcoal derived from Amazonia wood wastes

Controlling the carbonization process in brick kilns based on temperature and selecting raw material to reduce heterogeneity are key challenges in producing high-quality charcoal from Amazonia wood wastes. The study's main objective was to investigate how the final carbonization temperature and different Amazonian wood species affect the carbonization efficiency and the charcoal apparent density (CAD). After determining wood basic density (WBD), the wastes underwent carbonization on a laboratory scale at four final temperatures (400, 500, 600, and 700 °C). The gravimetric yield in charcoal (GYC), the specific consumption of firewood (SCF), and the CAD were evaluated. The CAD ranged from 0.248 (T. guianensis) to 0.656 g cm−3 (Licania sp.) and showed a positive correlation with WBD at all temperatures (400 °C - r = 0.954, 500 °C - r = 0.944, 600 °C - r = 0.930, and 700 °C - r = 0.927). Wastes from the species P. suaveolens and D. excelsa showed the highest mean values of GYC regardless of the carbonization temperature. The increase in the final carbonization temperature from 400° to 700°C reduced the GYC and increased the SCF and CAD. The species T. guianensis (25.6%), Manilkara sp. (25.4%), and D. excelsa (24.7%) showed more significant reductions in GYC from 400° to 700°C. Thus, temperatures below 500 °C are recommended for charcoal production from Amazonia wood wastes to provide better carbonization performance. In our study, charcoals from Licania sp., D. excelsa, and Manilkara sp. were the densest and, therefore, most suitable for the steel industry.

Charcoal of logging wastes from sustainable forest management for industrial and domestic uses in the Brazilian Amazonia

There is a gap in the literature regarding the quality and suitability of charcoals produced from the abundant logging wastes from sustainable forest management in the Brazilian Amazonia. Our study aimed to characterize and group charcoals produced from the wastes of 20 logged native species in an Amazonia Forest Management Area according to their physical, chemical, and energy properties. Moreover, we analyzed the carbonization mass balance and oil equivalent energy fraction of charcoal. We verified significant variations for charcoal bulk density (0.423–0.620 g cm−3), gravimetric yield in charcoal (34.4–45.5%) and in non-condensable gases (15.2–25.0%), ash content (0.5–9.6%), yield in fixed carbon (24.4–33.2%), energy density (12.3–18.4 GJ m−3), energy yield (53.8–70.9%), and retained carbon (54.1–71.0%). Our study revealed that the total extractives overcame the effect of lignin on the carbonization mass balance, yields, and charcoal quality from logging wastes. These biofuels present suitable equivalences with fossil fuels; however, their use must consider quality. Principal component analysis segregated charcoal into five groups with similar characteristics for carbonization in brick kilns to supply the local steel industry and domestic systems in the Amazonia.

PHYSICAL, MECHANICAL AND ENERGETIC PROPERTIES OF Tachigali chrysophylla UNDER DIFFERENTS FINAL CARBONIZATION TEMPERATURES

The charcoal production from wood wastes is a viable and suitable alternative to income Amazon region. However, it is necessary to define the best parameters for the optimization of production. The aim was to study the effect of three final temperatures (300, 400 and 500ºC) in physical, mechanical and energetic properties of wood waste charcoal of Tachigali chrysophylla. The material was collected in an area under second cutting cycle forest management in the Amazon. Branch waste of three trees were cut in 20x20x40mm³ samples and carbonized at different final temperatures at 1.6°C.min-1. The apparent density, mechanical strength and modulus of elasticity at parallel compression, gravimetric yield on charcoal and the higher heating value were determined. The data were analyzed with p<0.05. The final temperature affected the evaluated charcoal properties . The temperature of 500ºC is indicated when a charcoal with high mechanical strength at parallel compression and higher heating value is aimed. When the objective are higher apparent density and gravimetric yield in charcoal, the final temperature of 300ºC should be used.

CHEMICAL AND ENERGETIC CHARACTERIZATION OF Eucalyptus grandis × Eucalyptus urophylla CLONES SUBJECT TO WIND DAMAGE

ABSTRACT Wind damages are common in forest plantations and the use of this wood can minimize losses. The objective was to evaluate the chemical composition and the energetic potential of wood and charcoal from trees subject to wind damage. Eight (A to H) two-years-old Eucalyptus grandis × Eucalyptus urophylla clones were selected in a region where wind damage is frequent. The basic density, calorific value, chemical composition of wood and calorific value, immediate chemistry and gravimetric yield of charcoal were determined for all clones. Materials with high lignin content and low S/G ratio had higher gravimetric yield. The energy density of wood and charcoal showed high relationship with the basic and apparent relative density, respectively. All materials showed potential for bioenergy, but the clone E stood out with higher gravimetric yield and energy density.

Propriedades energéticas da madeira e do carvão vegetal de Cenostigma macrophyllum: subsídios ao uso sustentável

O objetivo deste estudo foi avaliar a qualidade da madeira de Cenostigma macrophyllum Tul para uso energético e determinar os rendimentos e propriedades do carvão vegetal produzido em diferentes temperaturas de carbonização. Foram retirados discos de 3 cm de espessura nas posições basal, 25%, 50%, 75% e 100% da altura comercial do fuste. Os discos foram cortados em cunhas e metade destas foi utilizada para análises na madeira e a outra metade foi carbonizada em temperaturas finais de 400 ºC, 500 ºC e 600 ºC para avaliação dos rendimentos e características do biorredutor. A densidade básica (1,2 g cm-3), teor de lignina (34%), poder calorífico superior (4.845 cal g-1) e rendimento gravimétrico de carbonização (RGC) aos 400 ºC (41,5%) da madeira do caneleiro se destacaram. O aumento da temperatura de pirólise da madeira de 400 ºC para 600 ºC resultou em acréscimo de 29,4% do teor de carbono fixo e redução de 19% e 63,4%, respectivamente, do RGC e do teor de materiais voláteis do carvão vegetal. Conclui-se que a espécie apresentou valores satisfatórios para produção energética.

EFFECT OF EXTRACTIVES AND CARBONIZATION TEMPERATURE ON ENERGY CHARACTERISTICS OF WOOD WASTE IN AMAZON RAINFOREST

ABSTRACT The objective of this study was to evaluate the effect of extractives soluble in hot water, besides final carbonization temperatures, on the gravimetric yield and properties of charcoal for waste of three native forest species from the Amazon region. Waste cuttings of Ipé, Grapia and Maçaranduba species, from the machine processing for joinery of a company in the State of Pará, were used. Carbonization was carried out in an adapted electric furnace with a heating rate of 1.67°C min-1 and final temperatures of 500, 600 and 700°C. The waste was carbonized fresh after extraction in hot water to remove extractives. Gravimetric yields were analyzed, as well as chemical features and high heating value. In the evaluation of the experiment, arranged in a factorial scheme with three factors (species x temperature x material with and without extraction), and Principal Component Analysis used too. The presence of extractives (soluble in hot water) from wood waste had little influence on the gravimetric yield and immediate chemical composition of charcoal; however, it showed a greater high heating value and lower contents of hydrogen and nitrogen. The increase in the final carbonization temperature reduced the gravimetric yield in charcoal, the content of volatile materials and hydrogen, with a higher content of fixed carbon, carbon and high heating value. The treatments with the best energy characteristics were obtained from Ipé and Maçaranduba charcoals with extractives produced at 600°C, in addition to Ipê and Maçaranduba charcoals with and without extractives obtained at 700°C.

INFLUÊNCIA DAS PROPRIEDADES QUÍMICAS E DA RELAÇÃO SIRINGIL/GUAIACIL DA MADEIRA DE EUCALIPTO NA PRODUÇÃO DE CARVÃO VEGETAL

O trabalho teve como objetivo determinar a influência das propriedades químicas (composição elementar, teores de extrativos totais, lignina total e holocelulose) e relação siringil/guaiacil, da madeira de diferentes materiais genéticos de eucalipto na produção de carvão vegetal. Utilizaram-se na pesquisa quatro clones híbridos de Eucalyptus, aos 7 anos de idade, sendo 6 árvores por clone, totalizando 24 unidades amostrais. Houve diferença significativa, a 5% de significância, entre os tratamentos para a composição elementar, teores de extrativos totais, lignina total e holocelulose e relação siringil/guaiacil da madeira, como também, para os rendimentos gravimétricos em carvão vegetal, em gases condensáveis e em gases não condensáveis, teores de carbono fixo e de materiais voláteis e para o poder calorífico superior do carvão vegetal. Para o teor de cinzas e densidade relativa aparente do carvão não foram observadas diferenças significativas ao mesmo nível de significância. Concluiu-se que existe variabilidade na qualidade da madeira dos quatro materiais genéticos avaliados, tendo, os mesmos, correlações distintas, tanto no rendimento quanto na qualidade do carvão vegetal. Todos os materiais genéticos apresentaram, de modo satisfatório, rendimento gravimétrico em carvão vegetal e qualidade. As madeiras dos clones com baixa relação siringil/guaiacil apresentaram aumento no rendimento em carvão vegetal. A composição química das madeiras dos quatro clones, de modo geral, não apresentou correlações significativas, a 5% de significância, no rendimento e qualidade do carvão.

CORRELATIONS BETWEEN AGE, WOOD QUALITY AND CHARCOAL QUALITY OF EUCALYPTUS CLONES

ABSTRACT Brazil is world's greater producer of charcoal, and the Brazilian state Minas Gerais presents the greater production of said product. The wood proprieties influence the charcoal quality, making important to know them, it is known that these proprieties vary according to the age of the tree. With that being said, this research aimed to determine the correlations existing between age, the proprieties of the wood and charcoal proprieties. Three Eucalyptus sp. clones from Gerdau S/A were evaluated, at four ages, 3, 4, 5 and 7. From each tree, five discs were removed (0%, 25%, 50%, 75% and 100% corresponding to the commercial height of the trunk). We determined the core/sapwood relationship, basic density, chemical composition of the wood, the calorific value of the wood and of the charcoal, the gravimetric yields, apparent relative density and charcoal chemical analysis, in addition to the analysis of the condensable and non-condensable gases. Correlations between age, proprieties of the wood and charcoal were performed. It was observed a negative correlation between the age of the wood and charcoal ashes content, regardless the clones evaluated. A positive correlation between the basic density of the wood and the apparent density of the coal and a positive correlation between the lignin of wood content and the coal apparent density were observed, as well. The siringil/guaiacil relation, which determines the quantity of each type of lignin existent on the wood, presented a negative correlation with the gravimetric yields in charcoal. Therefore, it is concluded that the age of the tree influenced the proprieties of the wood, regardless the clone; the age of the genetic material did not influence the gravimetric yield in charcoal; the GG 680 clone presented greater potential to produce charcoal, considering only the proprieties of the wood.

ANÁLISE DAS PROPRIEDADES DA MADEIRA E DO CARVÃO VEGETAL DE HÍBRIDOS DE EUCALIPTO EM TRÊS IDADES

Foram estudadas madeiras de híbridos de Eucalyptus grandis x Eucalyptus urophylla em três diferentes idades. As características das madeiras e dos carvões produzidos, a partir dessas madeiras, bem como influência da madeira nas características dos carvões produzidos foram avaliadas. Foram realizadas análises químicas (extrativos, lignina, cinzas, análise elementar), densidade básica e poder calorífico superior - PCS nas madeiras. O carvão foi produzido em forno tipo mufla, com taxa de aquecimento 1,67 ºC.min-1 e temperatura final de 450 ºC. Para os carvões, foram realizadas análise imediata, análise elementar e rendimento gravimétrico do processo de pirólise. Foi observado um aumento nos valores de densidade, teor de extrativos, teor de carbono e relação C/H da madeira com a maturidade da árvore. Outras características como teor de cinzas e relação S/G tiveram seus valores diminuídos com a idade da árvore. Maior rendimento gravimétrico em carvão e em gases não-condensáveis foram encontrados no material mais maduro.

A new technology for the combined production of charcoal and electricity through cogeneration

This paper presents an historical approach on the development of the existing biomass carbonization technologies in industrial operation in Brazil, the biggest charcoal producing country in the world. The gravimetric yield of charcoal from wood does not usually surpass 25%; the time of each operation cycle is more than seven days; and less than 50% of the energy contained in the feedstock is transformed into charcoal – the rest is discharged into the environment. The electricity generation associated with charcoal production is nowadays inexistent in Brazil. This paper presents the development of an industrial technology of semi-continuous pyrolysis process, characterized by using metallic kilns with forced exhaust system: the Rima Container Kiln (RCK). The results of the test runs are related to 5 m3 and 40 m3 kilns, with a thermal power of 200 kW (pilot scale: 5 m3) and 3000 kW (industrial scale: 40 m3). The low heating value of the pyrolysis gases is 670 and 1470 kJ/m³, respectively.The main results are: a 3 h carbonization time; an average productivity per kiln of 1 ton of charcoal per hour; and a gravimetric yield of 35%. In this paper, four scenarios for the conversion of exhaust gases and tar into electricity were evaluated: the Conventional Rankine Cycle (CRC) and the Organic Rankine Cycle (ORC), each one with and without forest residues utilization. It is shown that the best economic indicators correspond to the scenario where ORC technology is used. The electricity generation cost is around U$30/MWhe for ORC and US$40/MWhe for CRC.

Evaluation of Carbonization of the Hedgehog of Brazil Nut in Oven Type Metal Drums

This work aimed to evaluate the production of charcoal from the hedgehog of the Brazil nut using metal drums as a reactor, considering the adaptive feature for mobility, typical of this exploitation. The average time of carbonization was relatively short, 4:45 hours, which generated a yield of charcoal of 19.11%. The content of material with incomplete carbonization was of 35.77%. His basic density was 0.631g.cm -3 , since the bulk density was 0.231 g.cm-3. The average moisture content of the charcoal produced was 4.71%. Volatile materials, amounted to 20.79% of the total mass. The ash content was 0.87% and the fixed carbon was 78.33%. The calorific value was 7252.98 kCal.kg -1 . Thus, it can be conclude that the method of the drum is adapted to charcoal producing from the hedgehog of the Brazil nut, however, improvements in thermal insulation of the reactor can be proposed for future work; gravimetric yield in charcoal was low when its performance is compared to other methods of carbonization, probably by the lack of thermal insulation; carbonization time in the reactor was considerably lower than those obtained for the carbonization in muffle for similar products.

Correlações entre as propriedades da madeira e do carvão vegetal de híbridos de eucalipto

Foram estudadas madeiras de híbridos de Eucalyptus grandis x Eucalyptus urophylla, em três idades diferentes, com o objetivo de avaliar o comportamento da madeira e do carvão vegetal produzido diante do aumento controlado de temperatura, bem como verificar a influência das características da madeira sobre o carvão vegetal. Foram realizadas análises químicas (extrativos totais, lignina, holocelulose, celulose, cinza e análise elementar) e térmicas (análise termogravimétrica - TG, análise térmica diferencial - DTA e calorimetria 1,67 ºC min-1 e temperatura final de 450 ºC. No carvão vegetal produzido, foram realizadas análise imediata, elementar e térmica. A densidade básica da madeira correlacionou-se positivamente com a relação carbono/ hidrogênio (C/H) e negativamente com os teores de cinza, nitrogênio, oxigênio, enxofre e relação siringil/ guaiacil (S/G). Os teores de cinza, nitrogênio, enxofre e S/G da madeira correlacionaram-se positivamente entre si e negativamente com a variável C/H da madeira. O teor de carbono fixo (TCF), o poder calorífico do carvão vegetal, o teor de carbono elementar e a relação C/H correlacionaram-se positivamente entre si e negativamente com o teor de materiais voláteis (TMV). O teor de lignina correlacionou-se positivamente com o rendimento gravimétrico em carvão (RGC) e negativamente com o TCF.

Influence of Chemical Composition of Eucalyptus Wood on Gravimetric Yield and Charcoal Properties

The objective of this study was to assess the chemical properties of wood from six clones of Eucalyptus spp. relative to charcoal yield and its properties, determine the correlations between the evaluated parameters and identify a clone of Eucalyptus having the greatest potential for charcoal to steelmaking use. The study of chemical properties included analysis of elemental composition, contents of cellulose, hemicelluloses, lignin, and ash, the syringyl/guaiacyl ratio (S/G), and the index of crystalline cellulose in the wood. The pyrolysis of wood was done in an electric laboratory oven. The gravimetric yield in charcoal, the content of volatile matter, fixed carbon and ash, higher heating value, and elementary composition were determined. Data were subjected to an analysis of variance, and after the difference between them was established, the Tukey test was applied. The Pearson correlation was employed as well. The results indicated that the contents of carbon, oxygen, and hydrogen in the wood significantly affected the charcoal yields and its higher heating value. Higher rates of crystalline cellulose favored the gravimetric yield in charcoal. The S/G ratio contributed more to the charcoal yield when compared to total lignin content.

Qualidade e rendimento do carvão vegetal de um clone híbrido de Eucalyptus grandis x Eucalyptus urophylla

This research aimed to analyze the quality and yields of the charcoal of a Eucalyptus grandis x Eucalyptus urophylla hybrid clone commercially named GG100 for use in iron industry at different ages, plantation sites and spacing. The wood was carbonized in a laboratorial electric furnace (muffle furnace) at a heating rate of 1.67 oC min-1 until the final temperature of 450 oC, remaining stabilized for 30 min. The gravimetric yield in charcoal, pyroligneous extract, non condensable gases and insoluble tar, proximate and elemental chemical composition, relative apparent density and higher heating value of the charcoal were determined. In general, the charcoal evaluated may be considered homogeneous based on chemical and physical aspects and can be used in the steel sector. The apparent relative density allowed the charcoal samples differentiation produced by the same pyrolysis condition. The results obtained suggest that the density of the charcoal is highly influenced by the wood origin. It was observed that higher values of higher heating values are positively related with carbon content and negatively related with oxygen, hydrogen and nitrogen contents and with gravimetric yield in charcoal.

Near Infrared Spectroscopy for Estimating Eucalyptus Charcoal Properties

Steel can be produced from vegetable charcoal used as a thermo reducer in steel blast furnaces. Hence, the metallurgical industry requires new solutions for controlling the quality of their charcoal in order to maintain the same quality standard. The objective of this study was to assess the properties of charcoal by near infrared spectroscopy. Partial least square (PLS) regressions were established for estimating fixed-carbon, volatile matter content and gravimetric yield of charcoal. These models were validated by cross-validations and independent test sets and presented similar performance. PLS-R models obtained from untreated NIR spectra for FCC and VMC yielded promissory statistics [ r2p of ∼0.9; root mean squared error of prediction ( RMSEP) of ∼3.3%; and ratio of the standard error of prediction to standard deviation ( RPD)>3] while the statistics of the calibrations for gravimetric yield had relatively lower magnitude ( R2p of ∼0.8, a RMSEP of ∼2.2 and RPD<2). Since new solutions are required for controlling the quality of charcoal with speed and precision, these models can be useful for monitoring charcoal quality in steel industries.