Charcoal Fines Research Articles

LCA of eucalyptus wood charcoal briquettes

This paper sets out to describe the environmental impact assessment for wood charcoal briquettes produced from eucalyptus wood in Brazil, with specific reference to those impacts associated with Global Warming Potential. To achieve that objective, the work was undertaken in accordance with ISO 14040 "Environmental management – Life cycle assessment – Principles and framework" which describes essential LCA characteristics and good practices. Charcoal briquettes are produced from two basic raw materials, charcoal fines and starch. The fines result from the production of charcoal from sustainably managed eucalyptus plantations. Starch is extracted from babaçu pulp in the Amazon region. Multi–output processes were allocated based on income from the different by-products. The results showed that more than 90% of incoming CO 2 was due to biomass production for charcoal, and the remainder to starch biomass production. Based on Brazilian data, as well as information provided by the GaBi4.3 database, it turned out that supplying the energy content of 1 kg of briquettes resulted in the sequestration of 3.9690 kg of CO 2, i.e. around 4 kg of CO 2 per kg of briquettes produced. CO 2 emissions throughout the briquette production process are totally compensated for by the environmental quality of the raw materials used.

Production of Solid Fuel from Ipomoea carnea Wood

Ipomoea carnea woody stems were pyrolyzed in a laboratory-scale reactor in the temperatures ranging from 350° to 600°C and at constant heating rate of 5°C/min. Yield, density, ash content, volatile matter, fixed carbon content and calorific value of the charcoal samples produced were evaluated. Charcoal yield ranged from 24.23% to 37.89 wt% and calorific value varied from 17.29 to 33.47 MJ/Kg. Conversion of charcoal fines to solid fuel improved combustion quality. Mass balance experiments of pyrolytic decomposition products of I. carnea yielded much higher percentages of non-condensable liquid (59.2–61.8 wt%) as compared to those of tar (4.2–4.8 wt%) and gas (7.3–8.2 wt%) fractions.

The role of water vapor in the charge elimination process for flowing powders

Effective charge elimination of flowing powders in a solid-gas multiphase system by addition of charge-neutralizing carriers, such as ammonia (gas), water droplets (liquid), and activated charcoal fines (solid) have been reported. The charge neutralization process, however, is still not clearly known at present. This paper proposes a general mechanisms of charge elimination based on hydrated ion clusters (H 2O) n H + and (H 2O) n OH −, and their polymers. Measurements of electrostatic charges of flowing glass beads in a continuous copper pipe loop with air carrier containing oxygen, nitrogen, or ammonia using an upgraded Faraday probe measuring system were made with water vapor contents ranging from 0% relative humidity (R.H.) up to 80% R.H. The agglomerate hydrated ion clusters are believed to act as the major charge carriers to neutralize charges on the particle surfaces or to redistribute them into the surrounding space. In the absence of water vapor, the charge elimination techniques tested in our experiments were found not to function properly. The effectiveness of the charge elimination process is strongly affected by the population of the clustered aggregates.

Qualidade do carvão vegetal produzido com madeiras da região de Manaus em fornos de alvenaria

Algumas características de madeiras da região de Manaus, no Amazonas foram determinadas, como identificação anatômica, densidade básica e umidade, visando reconhecer o material para produção de carvão vegetal. Identificou-se 28 famílias botânicas sendo que 50% do material foi representado por Anonaceae, Lecythidaceae e Sapotaceae. Quanto a gênero, encontrou-se 43, destes sobressairam-se Miconia, Guateria, Brasimum Goupiae Eschweilera, representando 38% das madeiras. As espécies Goupia glabra, Aldina heterophylla, Jacaranda copaia, Diplotropis purpurea e Tapirina guianensis foram as de maior ocorrência na madeira estudada. A densidade básica média foi 0,73 g/cm3 e a umidade média, sendo a madeira seca ao ar livre, ficou em 24.16% base úmida. A madeira foi carbonizada em fornos de alvenaria e do carvão obtido determinou-se características físicas e químicas. Os resultados médios foram: tamanho médio 45,30mm; friabilidade 15,46% de finos gerados menor que 13 mm e índice de quebra de 39,13%; tensão máxima de ruptura foi 43,36kgf/cm2; densidade aparente 0,51 e verdadeira 1,48; porosidade 65,28%; umidade 6,80%; matérias voláteis 17,65%; cinzas 2,29%; carbono fixo 80,06% e poder calorífico superior 6.826 Kcal/kg.

MEASUREMENT AND CONTROL OF ELECTROSTATIC CHARGES ON PULVERIZED COAL IN A PNEUMATIC PIPELINE∗

Abstract Pulverized coal particles flowing in a pneumatic pipeline are naturally charged to a detectable level due to collisions with pipe walls. Systematic charge measurements of Anthracite (AN) coals, Medium Volatile Bituminous (MVB) coals and Lignite A (LIGA) coals in a grounded copper pipe have been made with an upgraded charge measuring system. The net particle charges were found to be positive, although both negative and positive charges were detected in all experiments. Effects of air humidity and conveying velocity on particle charges were examined. The mean particle charge was found in the order of 10−12 Coulomb and the charge-to-mass ratio in the order of 10−5 C/kg. Charge elimination techniques by strict humidity control and by introducing neutralizing charge carriers, such as minus 1 μm activated charcoal fines, ammonia, and piezoelectric ionized gas were explored. Effective reduction of 70 % to 85 % of particle charges was achieved. A charge neutralization mechanism was proposed to interpreta...

Preparation of thyroxine (T4) and triiodothyroxine (T3) free serum avoiding charcoal fines.

Preparation of thyroxine (T4) and triiodothyroxine (T3) free serum avoiding charcoal fines.