Dear brothers and sisters, January 3, 2010;
Assalaamu Alaikum Wa Rahmathullahi Wa Bharakhathuhu.
Americans love to grill. Most use charcoal. Charcoal is produced in kilns. The input to the kiln is wood. Thus using charcoal to grill is carbon-neutral: the carbon that is withdrawn from the atmosphere by the plant is released during grilling.
Now we find electrical and gas grills in the market. This indicates a shift in the public taste. We suspect this shift in public taste might hurt charcoal manufacturers in US and other countries.
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August 14, 1997
For decades, Missouri's charcoal industry has produced 80% of the nation's barbecue fuel in a crude process as old as the log cabin, cooking up the blackened wood in giant kilns that billow forth columns of black, acrid smoke.
Under the broad outlines of the accord reached last month by Missouri Department of Natural Resources officials and representatives of three of the state's largest charcoal makers, most of the state's 374 kilns will install anti-pollution devices over the next seven years.
The majority of the state's charcoal kilns are based in the Ozark Mountains. On days when the ovens are operating, a dark pall often drapes the rolling landscape, leaving behind a residue of gritty soot. "The smoke will sit on the ground for miles," said David Hawkins, a farmer in rural Caulfield, a south Missouri town.
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The soot and other waste products are collected in other places. For details see the other parts of the web site below. We quote the part relevant to extend the life of charcoal kilns.
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When the smoke becomes transparent blue, wait about 5 minutes, then with the soil (that you have prepared beforehand), block the entrance of the firewood chamber to less than half the size and wait another 5 minutes. Then, completely block and seal the entrance of the firewood chamber with the soil. Remove the two chimney pipe segments. Cover the exhaust chimney using a can or other type of cover and block the air to choke and extinguish the fire in the kiln. As long as possible, maintain the state of no-oxygen. Wait about 4 hours until the temperature drops to less than 200 deg C. If possible, it is good to wait until the next day.
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Those who use gas stoves would notice that the flame from the stove is blue. In case some food gets spilled on the burner, until the spill is burnt away fully the flame is not blue. From these observations, we infer that when the exhaust of the charcoal kiln is blue flame, all the soot and other waste products have evaporated and now the cooking gas is coming out.
After closing all the inlets of the kiln blocking any further supply of oxygen the cooking gas is released. In the absence of oxygen the cooking gas remains gas until it reaches the oxygen in the atmosphere when it might burn. We make the following modifications to collect the cooking gas.
In the chimney provide two outlets, one exposed to atmosphere, and the other connected to a cooling chamber. The cooling chamber is filled with water in which a condenser is immersed. The hot exhaust from the kiln is passed through the condenser, cooled, collected and packaged as gas for use.
The charcoal kilns in the West would have the 'emission control device' to remove the contaminants from escaping into the atmosphere. However in other countries these wastes are collected as vineager initially and the soot could be collected in soil. We do not describe these processes.
Once the air inlets to the charcoal kiln are closed as soon as cooking gas starts coming out, and after the cooking gas is collected instead of locking it to make charcoal for grilling, we would be left with carbon with minor residual cooking gas. This carbon is indeed trapped carbon dioxide in this cycle.
Carbon dioxide in air -- absorbed by plants to make wood -- wood is processed in charcoal kiln to extract useful waste before the cooking gas exits, and is kept at high temperatures until most of the cooking gas is collected, givin carbon. We bury this carbon or use it in any number of ways removing the carbon dioxide from reaching the atmosphere. These carbon pellets recovered from the charcoal kilns should earn carbon-credits.
Even though we discussed the extension of the financially useful life of charcoal kilns in America, the process of blocking the air inlet at the correct time and collecting the hot cooking gas coming out as exhaust could be done everywhere. We hope such modification of the charcoal kilns could be done in developing countries as well and they too earn carbon credits while improving their living standards as well.
The emphatic answer is 'No.'
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Smokeless fuel from carbonized sawdust
Snehalatha K. Chembukulam, Arunkumar S. Dandge, Narasimhan L. Kovilur Rao, K. Seshagiri, R. Vaidyeswaran
Ind. Eng. Chem. Prod. Res. Dev., 1981, 20 (4), pp 714–719
DOI: 10.1021/i300004a024
Publication Date: December 1981
... The procedure adopted for the carbonization experiments on sawdust was the same as that prescribed for coal except that: (i) the initial temperature of the furnace was maintained at 100 degree C before it was brought onto the assay tube; (ii) the temperature of the furnace was brought to the desired level at the rate of 5 degree C/ min and then maintained for 1h; (iii) about 10 g of sample was taken for experiments instead of 20 g. The temperature of first evolution of gas and the temperature of evolution of the oil vapor were noted. At the end of the experiment the weight of charcoal, the weight of tar and pyroligneous liquor together collected in the condenser, and the volume of the gas collected in the aspirator, its temperature, and pressure were noted. ...
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Thus cooking wood and other agricultural products and collecting the exhaust is part of the literature. Whatever we have described is an obvious extension and thus is not patentable. Accordingly there could be no patent covering the method described by us.
With prayers to Allah Subhana Wa Taala,
Your brother,
Mohideen Ibramsha
Was Salaam