Coal is burned most days in my neighborhood in central Beijing. Even the newer electric heaters installed this year didn't stop my neighbors from cooking and keeping warm with smoke-spewing briquettes. Coal is a fact of life. But some businesspeople are marketing boilers that make the best of coal by burning it in a cleaner way, reports Feng Yongfeng of the Guangming Daily in a story republished at China Dialogue.
One such technology was developed by the Beijing Xiongcai Group, whose chairman, Wang Yongjiang, explains:
"Normally coal is burned from underneath," he explains, "but our boilers burn the coal from above, which allows us to collect the soot and burn it again. When the harmful components in the soot are exposed to temperatures over 800 degrees, they are burnt away, massively reducing emissions. The flame inside burns pure blue and translucent, which means the fuel is being burned completely. Yet the coal we use only contains 3,500 kilocalories per kilogram - about half the energy content of fine coal." ...
Since 2000 the firm has approached these questions by treating fuel and combustion technology as a single, integrated subject. The company's patented biomass boiler and "biomass coal" fuel together make up a system for burning biomass combined with lower grade coal, which burns with a heat energy efficiency of more than 80%. Its emissions are on a par with the cleanest of boilers, and the system reduces energy consumption and waste. The "biomass coal" is made up of compressed chaff, tree leaves and branches, household waste, gangue, coal powder and other low-grade coals. The resulting fuel is dense, burns completely, does not produce black smoke and fixes sulphur. When burned in the boiler, it can produce the same heating effect as fine coal. The waste from the boiler also has a number of applications: it can be used in water purification, in building insulation and as fertiliser. Both the biomass fuel and waste from the boilers is transported in sealed packages to prevent any secondary pollution.
Check out the full article for another example of cleaner coal burning. Coal will never be as clean as greener energy sources, but it's unlikely to be eradicated anytime soon. If we're going to burn it, we should burn it right.