A clean, efficient system for producing Charcoal, Heat and ...

charcoal have been found, dated to 30,000 years BC. The ‘charcoal’ used here was more likely to be charred sticks from a fire, rather than charcoal produced intentionally. The bronze and iron ages, starting around 5500 years ago, are probably the first use of charcoal as a fuel. Wood could not produce the high ................
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