Popcorn de-ashing process

Abstract

A process for de-ashing coal wherein a wet or methanol soaked coal is subjected to a high current pulse of electrical energy to induce rapid heating, causing an explosive release of vapor breaking the coal particles apart and separating the organic fraction from the inorganic. The particles are swept along by the large volume of gas and the particles are separated by fluidization. Heavier ash particles are gravity separated from the lighter organic coal particles. The de-ashed organic coal particles leave the top of the fluidized bed. They are then separated in a cyclone separator from the vapor. The vapor is then condensed to a liquid and discharged or recycled.

1 . A process for de-ashing coal, peat and biomass comprising the steps of, 
 (a) grinding a coal, peat or biomass fuel into particles and while doing so, removing non-interstitial liquids and any gangue;    (b) fractionating the ground particles by subjecting them to a current of electrical energy sufficient to induce rapid heating and vaporization of interstitial liquids within the particles and bursting of said particles wherein the exit stream is organic matter, vapor and ash;    (c) removing the ash from the exit stream;    (d) removing the vapor from the stream; and    (e) using the organic matter as a de-ashed product.    
   
   
       2 . The process of  claim 1  further comprising the steps of soaking the ground particles in a working fluid prior to fractionating the particles; condensing the vapor removed from the stream to a liquid; separating the water from the working fluid in the liquid; and recycling the working fluid back into the process.  
   
   
       3 . The process of  claim 2  wherein the working fluid is methanol.  
   
   
       4 . The process of  claim 1  wherein the step of removing the ash from the exit stream is accomplished in a fluidized bed.  
   
   
       5 . The process of  claim 1  wherein the step of removing the vapor from the stream is accomplished by cyclone separation.  
   
   
       6 . The process of  claim 1  wherein the current of electrical energy is produced by electrodes placed across a stream of flowing ground particles for direct resistance heating.  
   
   
       7 . The process of  claim 1  wherein the current of electrical energy is produced by induction with a coil configuration surrounding a stream of flowing ground particles.