Charcoal Producers Research Articles

The Effect of Carbonization on wood Structure of Dalbergia Violacea, Stryphnodendron Polyphyllum, Tapirira Guianensis, Vochysia Tucanorum, and Pouteria Torta from the Brazilian Cerrado

Brazil is the world’s largest producer of charcoal and a great part of this material still comes from native forests – especially from the cerrado biome, which is highly impacted by anthropogenic degradation. The need to control charcoal production increases the demand of charcoal identification, but there is little information about the anatomical modifications due to carbonization. In this paper, fresh and charred wood samples from five Brazilian species were analyzed (Dalbergia violacea, Stryphnodendron polyphyllum, Tapirira guianensis, Vochysia tucanorum, and Pouteria torta). Anatomical characters were described and measurements of the main anatomical features of wood and charcoal were statistically compared. Minor modifications were observed: reduction of tangential vessel diameter was the most evident change after carbonization; shrinkage of rays (in width) occurred only in some individuals. The present study supports the identification of charred woods, hopefully contributing to the control of charcoal production, and to palaeoenvironmental and archaeobotanical studies.

Pressure effect on the quality of eucalyptus wood charcoal for the steel industry: A statistical analysis approach

Brazil is the leading producer and consumer of charcoal, 75% of which goes to the steel industry alone. The carbonization processes are generally small-scale technologies that are difficult to control, with relatively low gravimetric yields. New technologies are currently being developed to improve those figures. One such technique is pressurized pyrolysis. Recent studies have shown that using pressure can increase gravimetric yields by 50% and considerably reduce carbonization time. The purpose of this paper was to study statistically how pressure impacts on the quality of the resulting charcoal. We applied a random factorial design and used the General Linear System procedure to perform the statistical analysis. The experimental study was carried out on the wood of Eucalyptus grandis and involved three relative working pressures (0, 5 and 10 bars), two carbonization temperatures (450 and 600 °C) and three wood moisture contents (0, 15 and 110%). Five response variables were analyzed and discussed following a random factorial design: charcoal yield (y char ), fixed carbon yield ( y fC ), bulk density ( D), fixed carbon content ( fC) and gross calorific value ( GCV). The best “steel” quality charcoal seemed to be obtained with an anhydrous wood, a pressure of 10 bars and a temperature of 600 °C.

Miombo Woodland Utilization and Management, and Impact Perception among Stakeholders in Zambia: A Call for Policy Change in Southern Africa

ABSTRACT Miombo woodland is important for both wood and non-timber forest products (NTFPs). The most commonly harvested products are timber, firewood, charcoal, fencing materials and materials for making farm tools and household items. The non-timber forest products harvested include mushrooms, fruits, medicines etc. A range of user groups such as timber producers, farmers and charcoal producers are involved in the exploitation of different types of woodland resources. Differences in priority of wood products and poor understanding of the Miombo ecosystem often result in each group attributing the negative impacts on the woodland to the other groups. In particular, timber producers accuse the charcoal producers of causing the depletion/decline of the timber species population which are cut as a by-product of charcoal production. However, there is clear evidence suggesting that timber species tend to do better in charcoal production and areas opened up due to slash and burn. This suggests that charcoal production, slash and burn agriculture and timber production may be integrated in forest management. As a result, there is need to formulate policies that provide for the integration of these different land use types into forest management.

Assessment of Charcoal Production and Impact of Environmental Policies in Limited Forest Resources Countries: The case of Togo, West Africa

In this study, plant species currently used for charcoal production were identified in major charcoal productioncentres or supply basins (SBs) in Togo. Impact of environmental policies on this activity were also assessed. Therefore,a sample of 310 charcoal producers in four SBs in different ecological areas throughout Togo, were selected. Lawregulating charcoal production, currently appointed to protect the environment were also analysed. Results revealthat the average quantity of charcoal produced is 323,353 tons per year. Producers are women (52%) averaging 39years of age. A category of seasonal producers are pupils who practice this activity during the holidays. Charcoal ismade in temporary kilns at the soil surface. In each SB an average of 15 native plant species are used. Transportersinfluence traders and traders influence producers with regard to charcoal quality. However, demand comes fromfinal consumer who prefers heavy charcoal. This study shows that environmental policies do not influence charcoalproduction in Togo due to the weakness of existing laws, no coordination between the institutions in charge of theenvironment and the overall failure of the energy policy.

Impact of charcoal production on woody plant species in West Africa: A case study in Togo

In Togo, fuel wood and charcoal account for more than 80% of total householdenergy requirements. Charcoal production results in a high pressure on the commonly used woody species. This study was carried out to assess the impact of charcoal production on the vegetation. Surveys involving 310 charcoal producers from 4 production areas were carried out. In each production area, density, diameter, height and basal area of woody species were measured both in unexploited plots and exploited plots. Inside the 4 charcoal production areas, 158 woody species were identified including 34 regularly exploited for charcoal production, that is, 15 preferred and 19 by default. Diversity indexes (Species Richness, Shannon and Evenness) and variability of densities are significantly higher in unexploited plots than those in exploited plots. The average heights vary between 4 and 7 m inside the exploited plots and from 6 to 9 m inside the unexploited plots. Average diameter and basal area are statistically not different inside unexploited plots and exploited plots. The most common regeneration methods inside the 4 charcoal production areas are seedlings and coppices. The preferred species regenerate better in exploited plots than those exploited by default. The study concludes that the negative effect of charcoal production on natural ecosystems has resulted in the depletion of the biodiversity, density, height, diameter of the stands and basal area of the woody species. Key words: Charcoal production, plant diversity, woody population structure, regeneration.

Burning biodiversity: Woody biomass use by commercial and subsistence groups in western Uganda’s forests

Woodfuels are the most heavily used energy source in sub-Saharan Africa. We analyzed the ecological impacts and modes of access of five user groups (domestic consumers, gin distillers, brick manufacturers, charcoal producers, and tea companies) drawing biomass energy from natural forests in western Uganda. While domestic consumers use the most species for fuelwood (>50), their consumption is likely sustainable because they generally harvest fast-growing species from fallows on their own land or their neighbors’. Charcoal producers prefer old-growth hardwood species and are responsible for the greatest loss of natural forests. They access forests by finding landholders who, either willingly or through coercion, allow trees on their lands to be cleared. The impact of charcoal production is exacerbated by a license system that undervalues natural forests and rewards rapid harvests across large areas. The tea industry consumes mainly eucalyptus wood ( Eucalyptus spp.) from corporate plantations, but they indirectly create pressure on natural forests by hiring immigrants who subsequently settle in and clear forest remnants. If such practices continue, forest remnants will soon be exhausted, leaving Kibale National Park as the last natural forest in the region. Forest remnants are a vital source of water, medicinal plants, and energy for local citizens and to protect them from over-exploitation, policy makers should target the charcoal and tea industry for reform. Support for local land management institutions governing access to fallows and successional forests will inevitably enhance the policy interventions.

World at work: Charcoal producing industries in northeastern Brazil

World at work: Charcoal producing industries in northeastern Brazil

Urinary Biomarkers in Charcoal Workers Exposed to Wood Smoke in Bahia State, Brazil

Abstract Charcoal is an important source of energy for domestic and industrial use in many countries. Brazil is the largest producer of charcoal in the world, with ∼350,000 workers linked to the production and transportation of charcoal. To evaluate the occupational exposure to wood smoke and potential genotoxic effects on workers in charcoal production, we studied urinary mutagenicity in Salmonella YG1041 +S9 and urinary levels of 2-naphthol and 1-pyrenol in 154 workers of northeastern Bahia. Workers were classified into three categories according to their working location, and information about socio-demographic data, diet, alcohol consumption, and smoking was obtained using a standard questionnaire. Spot urine samples were collected to evaluate urinary mutagenicity and urinary metabolites. Urinary mutagenicity increased significantly with exposure to wood smoke and was modified by smoking. The prevalence odds ratio was 5.31, and the 95% confidence interval was 1.85; 15.27 for urinary mutagenicity in the highly exposed group relative to the nonexposed group. The levels of urinary metabolites increased monotonically with wood smoke exposure and were associated with the GSTM1 null genotype, which was determined previously. The prevalence odds ratio (95% confidence interval) for higher levels of 2-naphtol among the highly exposed was 17.13 (6.91; 42.44) and for 1-hydroxyprene 11.55 (5.32; 25.08) when compared with nonexposed workers. Urinary 2-naphthol was the most sensitive indicator of wood smoke exposure. This is the first reported measurement of internal exposure to wood smoke among charcoal workers, and the results showed that these workers receive a systemic exposure to genotoxic compounds.

Characterization of tree macroremains production in a recently burned conifer forest in northern Québec, Canada

The production of plant macroremains was studied in a conifer forest twomonths after it burned in 1996 in northern Quebec. The proportions ofvarious types of charred and uncharred pieces (needles, cones andwood) produced by black spruce (Piceamariana) and jack pine (Pinusbanksiana) were determined by sampling around individual trees.Both species produced equivalent masses of charred material, but pieces of woodcharcoal from jack pine are generally larger that those of black spruce. Theproportion of charred versus uncharred needles is the bestindicator of the species dominance in the forest. Although the fall of uncharredneedles is delayed from the time of a fire, they contribute to more than half ofall remains produced. Jack pine cones remain on the tree for a long time after afire, while charred cones of black spruce are dehiscent (cones come off thebranches easily). Trees are poor wood charcoal producers compared toundergrowth shrubs. As a result, the macroremains assemblage associated with afire event is made up of large amount of uncharred material from trees and alarge proportion of charred pieces produced by undergrowth vegetation. Modernassemblages of plant macroremains indicate that in order to reconstruct pastvegetation associated with fire disturbance, it is important to distinguishbetween the various types of remains, because wood charcoal is mainly producedby material that is already dead.

Production and Spatial Price Differences for Charcoal in Uganda

Charcoal production activity assumes importance not only for generating large employment and income and supplying major fuel requirements in Uganda but also for triggering environmental degradation. Based on production and marketing data collected from one of the important charcoal producing districts, namely, Nakasongola, this study found that charcoal production being less capital intensive and risk free, is mainly carried out by numerous small, economically weak and unorganised individual producers. The price-distance relationship was analysed for the average prices of a bag of charcoal prevalent in each town over a stretch of 140 km between Kampala, the capital and main consuming center for charcoal in Uganda, and Kafu Bridge during the years 1995 and 1999. A movement of 1 km from Kampala resulted in a price decline of about 28 UShs in 1995 and 33 UShs in 1999 (prices held constant at 1995 level). The price-distance relationship and responsiveness of charcoal prices to distance from Kampala, as measured through distance elasticity of price, remained unchanged over the period 1995 to 1999. There is no statistical evidence to prove that the charcoal producers were better paid in 1999 than in 1995. It appears unlikely to halt the harmful environmental degradation effects of charcoal making activity without generating adequate alternate employment opportunities in rural areas and internalizing the full environmental costs of forest degradation in the consumer price of charcoal.

A113 バイオマス系木材の高級木炭生成に関する研究

In this study, thermo gravimetric (TG) and differential thermal analysis (DTA) of woods e.g. ezo-matsu, hinoki, momi, and sugi have been done at different heating rates and different ranges of temperature. Moisture content, peak temperature attained due to exothermic reactions, remnant ratios etc. have been determined in each cases and a comparison have been made between the above woods. Finally attempts have been taken to make charcoal from the woods by pyrolysis. The quality of charcoal however depends on pyrolysis temperature, pressure, time, heating rate, and moisture contents of the wood etc. Attempts have also been made to find the optimum values of the influential parameters for the production of a good quality charcoal. Charcoal producing from momi had the better quality among the four types of wood.

Community‐based use of mangrove resources in St. Lucia

The sustainable use of mangrove forests can effectively contribute to their conservation. The experience with an integrated conservation‐development project in St. Lucia showed that charcoal producers using mangrove fuelwood resources in a Marine Reserve Area have successfully changed their harvesting practices, reversing a trend of mangrove destruction. The conditions under which this change occurred included strengthening the organization of local users and their resource‐use rights, and building a community‐based management system, leading to the avoidance of open‐access conditions. Surveys of the mangrove, undertaken before and after management intervention, showed that while the mean stand diameter of the fuelwood trees did not change significantly, there was an increase in the density of stems and in total basal area of timber.

Two african woodfuel markets: Urban demand, resource depletion, and environmental degradation

This paper examines charcoal markets in two African cities: Mogadishu, Somalia and Kigali, Rwanda. Economic theory dictates that if woodfuel resources become scarce, their real price will increase commensurately with the interest rate. Although Rwanda and Somalia represent drastically different physical environments, both are considered to be wood-scarce. But neither market has demonstrated straightforward depletion effects. In Mogadishu, the price first rose and then fell in reaction to shifts in the structure of the charcoal market, relaxed regulations, and economic contraction. In Rwanda, the price bagan rising only after the closing of the Bugasera Region to charcoal producers. Charcoal must be increasingly produced from private farmland. These two case studies highlight the importance of agricultural land clearance, conflicting government regulations, and shifts in market structure in determining whether or not charcoal prices will demonstrate depletion effects, and whether or not charcoal production will lead to local environmental degradation.

高チタン滓の流動塩素化について

One of the applications of the fluidized bed chlorination process is described. Using high titanium slag, the preferential chlorination of impurities (especially FeO) and the chlorination of major constituent-TiO2 were studied.In the preferential chlorination, to prevent the bed from sintering, the addition of charcoal powder was effective. As reducing agent, charcoal producer gas was recommended, and optimum conditions were as follows; temperature 750-850°C, particle size 65-200mesh, Cl2 concentration 10%, u=, 0.2, mean residence time 30miuntes, and under these conditions, the Fe removal was over 90% and that of the other impurities. was about 70%.After this treatment, the slag could be chlorinated in fluidized bed with CO-Cl2 gas mixture at 1, 000°C or hlgher. But in these conditions, the construction materials were damaged quickly, so we studied the lower temperature chlorination using solid C as reductant. In this method, samples were prepared from slag. and pretreated slag, finely ground, mixed with charcoal powder, agglomerated with syrup binder and sized 35-150mesh.These two samples were chlorinated easily in fluidized bed. The optimum conditions were temperature-650-750°C Cl2 concentration 50%, (diluted with CO2 or N2), and u=0.1, and under these conditions, the reactions was concluded in 15 minutes with 80% or better chlorination ratios.

タングステン鉱の脱砒焙燒に関する研究

We investigated on the elimination of arsenic from scheelite by roasting which iscommonly found in tungsten ore and detested as an impurity that decreases the recovery of tungsten from alkali leach solution and lowers the quality of finished product.Following results were obtained.1) The roasting in oxidizing atmosphere to volatilize as arsenic trioxide was notcompletely successful, because unvolatile arsenate was partly formed. Dearsenizing ratio was 50-70% at 700-1000°C for 1 hr.2) The roasting in nonoxidizing atmosphere (N2, CO2, SO2) to volatilize mainly as arsenic sulphide was very effective. Dearsenizing ratio was almost 100% at 900-1000°C for 1hr.3) The fluosolid roasting process was applied. The very fine flotation concentrate (-325 mesh) was fluidized together with larger particles of pyrrhotite (60-100mesh) which was used to make stabilized bed and SO2 atmosphere. The cinder of concentrate was caught in the cyclone as carry over and pyrrhotitee was discharged as over flow. Dearsenizing ratio was90% at 800-900°C.The coarse jig concentrate (-100mesh) was fluoroasted in the charcoal producer gas. By the roasting of 1000°C for 20 minutes arsenic content decreased from 0.13% to 0.02% and it was superior to the oxidizing roasting.