Fluidized bed boiler (F.B.B.) and highly loaded coal water mixture (CWM) have recieved considerable world wide attention as prospective new coal utilization technologies.
The main advantages of FBB are considered as follows. FBB can burn a variety of fuels such as low grade coal including sedimented waste, and very high degree of desulfurization can be achieved directly in the combuster.
It has already been commercialized in industrial use, and 50 MW demonstration plant for verifing utility use are under construction.
Highly loaded CWM contains 60 to 75% coal suspended in water. It is ground into desirable particle size distribution somewhat finer than the standard pulverized coal grind and a complex chemical additive system gives the preferable CWM properties as liquid fuel.
Furthermore combustion test programms undergoing show excellent combustion characteristics because CWM include a lot of fine coal particle and water. So it is greatly expected that could be used as a substitute liquid fuel for heavy oil.