182,084 research outputs found

    Implications of Charcoal Briquette Produced by Local Communities on Livelihoods and Environment in Nairobi Kenya

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    The residents of Nairobi, Kenya, use 700 tonnes of charcoal per day, producing about 88 tonnes of charcoal dust that is found in most of the charcoal retailing stalls that is disposed of in water drainage systems or in black garbage heaps. The high costs of cooking fuel results in poor households using unhealthy materials such as plastic waste. Further, poor households are opting to cook foods that take a short time to prepare irrespective of their nutritional value. This article presents experiences with community self-help groups producing charcoal fuel briquettes from charcoal dust in poorer nieghbourhoods of Nairobi for home use and sale. Households that produced charcoal fuel briquettes for own use and those that bought them saved 70% and 30% of money spent on cooking energy respectively. The charcoal fuel briquettes have been found to be environmentally beneficial since they produce less smoke and increase total cooking energy by more than 15%, thereby saving an equivalent volume of trees that would be cut down for charcoal. Charcoal briquette production is a viable opportunity for good quality and affordable cooking fuel. Bioenergy and waste management initiatives should promote recovery of organic by-products for charcoal briquette production

    Variability in oxidative degradation of charcoal: influence of production variables and environmental exposure

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    <p>Charcoal is a key component of the Black Carbon (BC) continuum, where BC is characterized as a recalcitrant, fire-derived, polyaromatic material. Charcoal is an important source of palaeoenvironmental data, and of great interest as a potential carbon sink, due to its high apparent environmental stability. However, at least some forms of charcoal are clearly susceptible to environmental alteration and degradation over relatively short timescales. Although these processes have importance for the role of charcoal in global biogeochemistry, they remain poorly understood.</p> <p>Here we present results of an investigation into the susceptibility of a range of charcoal samples to oxidative degradation in acidified potassium dichromate. The study examines both freshly-produced charcoal, and charcoal exposed to environmental conditions for up to 50,000 years. We compare the proportion of carbon present in different forms between the samples, specifically with respect to the relative chemical resistance of these forms. This was undertaken in order to improve understanding of the post-depositional diagenetic changes affecting charcoal within environmental deposits.</p> <p>A wide range in chemical compositions are apparent both within and between the sample groups. In freshly-produced charcoal, material produced at 300 °C contains carbon with more labile forms than charcoal produced at ≥400 °C, signifying a key chemical change over the 300–400 °C temperature range. Charcoal exposed to environmental depositional conditions is frequently composed of a highly carboxylated aromatic structure and contains a range of carbon fractions of varying oxidative resistance. These findings suggest that a significant number of the environmental charcoals have undergone post-depositional diagenetic alteration. Further, the data highlight the potential for the use of controlled progressive oxidative degradation as a method to characterize chemical differences between individual charcoal samples.</p&gt

    Minimizing the Potential for Groundwater Contamination from Agricultural Point Sources

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    An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in the wastewater were on the order of 500 to 1000 parts per million (ppm). The final pesticide concentrations remaining after charcoal filtration were generally less than 10 ppm. Approximately 1514 L of wastewater was treated with 23 kg of charcoal before the charcoal was replaced. This resulted in an estimated pesticide loading rate on the charcoal of 0.05 to 0.10 kg pesticide active ingredient per kg activated charcoal. Incubation of alachlor-treated charcoal with a mixed culture of microorganisms resulted in approximately a 30% loss of alachlor after 21 d. These results suggest that on-site degradation of spent charcoal may be a feasible alternative to incineration, however more research is needed to fully determine its potential. A reduced adsorption of methylene blue dye with increasing amounts of trifluralin sorbed to charcoal occurred. Activated charcoal treated with 222 mg/g trifluralin sorbed only 19% of the amount sorbed by the control with no trifluralin present. These results suggest that methylene blue or other dyes might be used to indicate the remaining adsorptive capacity of a charcoal used for removing pesticides from wastewater

    Alkali extraction of archaeological and geological charcoal: evidence for diagenetic degradation and formation of humic acids

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    Charcoal forms a crucial source of archaeological and palaeoenvironmental data, providing a record of cultural activities, past climatic conditions and a means of chronological control via radiocarbon (<sup>14</sup>C) dating. Key to this is the perceived resistance of charcoal to post-depositional alteration, however recent research has highlighted the possibility for alteration and degradation of charcoal in the environment. An important aspect of such diagenesis is the potential for addition of exogenous 'humic acids' (HAs), to affect the accuracy of archaeological and palaeoenvironmental reconstructions based upon chemical analyses of HA-containing charcoal. However the release of significant quantities of HA from apparently pristine charcoals raises the question whether some HA could be derived via diagenetic alteration of charcoal itself. Here we address this question through comparison of freshly produced charcoal with samples from archaeological and geological sites exposed to environmental conditions for millennia using elemental (C/H/O) and isotopic (δ<sup>13</sup>C) measurements, Fourier Transform Infrared Spectroscopy (FTIR) and proton Liquid-State Nuclear Magnetic Resonance (<sup>1</sup>H NMR). The results of analyses show that the presence of highly carboxylated and aromatic alkali-extractable HA in charcoal from depositional environments can often be attributable to the effects of post-depositional processes, and that these substances can represent the products of post-depositional diagenetic alteration in charcoal

    KINETIKA PEMBAKARAN BRIKET ARANG ENCENG GONDOK

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    To overcome the problem needs an alternative fuel that is then taken for processing combustion water hyacinth water hyacinth into charcoal briquettes. This research aims to study the reaction kinetics of combustion of charcoal briquettes on the basis of accelerated depreciation of water hyacinth water hyacinth charcoal briquettes with various varioabel temperature and time to obtain the constant burning. This research was done by adding a binary solution in the form of starch with a concentration of 20% on charcoal water hyacinth which has a particle size 40 mesh, weighing 30 grams, then pressed and dried. Once dried water hyacinth dirimbang Charcoal briquettes and burned at a temperature of 200 oC, 250 oC, 300 oC, 350 oC and 400 oC until reaching constant weight. The results obtained by the heating value of water hyacinth charcoal briquettes at 5673 cal / garm, 30.002% ash content with 0.0475 MPa compressive strength. Combustion reaction rate constant of water hyacinth briquettes obtained at temperature of 200 ° C is 0.1230, the temperature of 250 ° C is 0.1680, a temperature of 300 ° C is 0.2364, the temperature of 350 ° C is 0.3782, and the temperature of 400 ° C is 0.4804. Frequency factor (Ko) of 0.9401 / h and the activation energy of 4445.9125 cal / mol L Then it can be concluded in this study the reaction takes place on the order of one. Key words: accelerated depreciation of water hyacinth charcoal briquettes, rioabel temperature and time to obtain the constant burnin

    Rethinking fuelwood: people, policy and the anatomy of a charcoal supply chain in a decentralizing Peru

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    In Peru, as in many developing countries, charcoal is an important source of fuel. We examine the commercial charcoal commodity chain from its production in Ucayali, in the Peruvian Amazon, to its sale in the national market. Using a mixed-methods approach, we look at the actors involved in the commodity chain and their relationships, including the distribution of benefits along the chain. We outline the obstacles and opportunities for a more equitable charcoal supply chain within a multi-level governance context. The results show that charcoal provides an important livelihood for most of the actors along the supply chain, including rural poor and women. We find that the decentralisation process in Peru has implications for the formalisation of charcoal supply chains, a traditionally informal, particularly related to multi-level institutional obstacles to equitable commerce. This results in inequity in the supply chain, which persecutes the poorest participants and supports the most powerful actors

    Effect of Activated Charcoal and Composition Activator Acid Sulphate on Palm Oil Waste Water Treatment

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    Purpose of this research is to exploit the shell and palm fiber become the active charcoal, by looking at the influence of the ratio mixture composition and effect of activator. this Active charcoal application as adsorbent to the liquid waste of crude palm oil. Initial treatment, shells and palm fiber dried first at a temperature of 1200C and carbonized. charcoal mix shell and palm fiber activation chemically with a solution of H2SO4 by way of immersed in the solution for 24 hours. The best quality activated charcoal obtained from the comparison of the 75% shell, 25% palm fiber with activator H2SO4 that has a yield of 95.94%, 4.9% moisture content, ash content 6.13%, iodine number 916.594 mg / g. Activated charcoal mixture palm shell and palm fiber can be used as adsorbent liquid waste CPO, which is indicated by a decline in these parameters in the waste water contaminants in CPO, which is a 7.49 pH of 9, TSS of 660 ppm to 325 ppm,COD becomes 237,12 mg/L from1577.60 mg/L

    Is adding charcoal to soil a good method for CO2 sequestration? - Modeling a spatially homogeneous soil

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    Carbon sequestration is the process of capture and long-term storage of atmospheric carbon dioxide (CO2) with the aim to avoid dangerous climate change. In this paper, we propose a simple mathematical model (a coupled system of nonlinear ODEs) to capture some of the dynamical effects produced by adding charcoal to fertile soils. The main goal is to understand to which extent charcoal is able to lock up carbon in soils. Our results are preliminary in the sense that we do not solve the CO2 sequestration problem. Instead, we do set up a flexible modeling framework in which the interaction between charcoal and soil can be tackled by means of mathematical tools. We show that our model is well-posed and has interesting large-time behaviour. Depending on the reference parameter range (e.g. type of soil) and chosen time scale, numerical simulations suggest that adding charcoal typically postpones the release of CO2
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