Coal is a mainstay in the global energy system, but some types of coal are less desirable than others.
Startup CoalTek today said it has landed its first large contract in China to upgrade low-rank coal with its system of microwave generators.
The company's technology, originally developed by an astrophysicist and geologist, zaps conveyor belts of low-grade coal with a series of microwaves to remove moisture from it.
Drying out the coal before burning it to produce electricity can increase the energy value by 50 percent and have the coal burn cleaner, CoalTek said. By passing it through its barrage of microwaves, coal with 25 percent moisture content can be reduced to 10 percent moisture in a way that uses half the energy of thermal drying systems, it said.
CoalTek set up a joint venture to process coal from Inner Mongolia in a project that's expected to reach about $350 million in investments. A facility will process about 10 million metric tones of low-grade "brown coal" a year.
The company is one of many startups developing ways to make industrial processes more energy-efficient. CoalTek calls its process a "clean coal" technology, though that term more often refers to efforts to pump carbon dioxide emissions from coal plants underground.