Process and apparatus for recovering rare earth elements from coal refuse

A process for concentrating rare earth elements, lithium, and titanium from coal refuse, comprising the steps of:

• crushing coal refuse to a particle size of less than approximately ⅜ inch by 0;
• admixing the crushed coal refuse with water in a raw feed sump to form an aqueous admixture;
• transferring the admixture to a first cyclone separator comprising a substantially cylindrical chamber defined by:
• an upper section having a first diameter, a middle section having a second diameter ater than said first diameter, thereby reducing the rotational speed of the admixture, and a conical lower section tapering from said second diameter to a lower apex;
• said first cyclone separator being configured to divide the admixture into a refuse-rich slurry stream with an ash content of approximately 80%, discharged through a first apex at the bottom of said conical section, and a carbonaceous-rich slurry stream withdrawn from an outlet positioned at said middle section having said second diameter;
• directing the refuse-rich slurry stream through a vibrating screen to dewater the stream, and returning the water collected from said dewatering step to the raw feed sump;
• transferring the carbonaceous-rich slurry stream from said outlet of the first cyclone separator to a second cyclone separator comprising a substantially cylindrical chamber defined by:
• an upper section having a first diameter, a middle section having a second diameter substantially equal to said first diameter, and a conical lower section tapering to a lower outlet,
• said second cyclone separator being configured to separate a low-quality carbon stream having an ash content of approximately 45% discharged through said lower outlet;
• and a high-quality carbon slurry, withdrawn through an intake positioned at said upper section;
• transferring the high-quality carbon slurry to a third cyclone separator comprising a cylindrical upper section having a first diameter and a conical lower section tapering to an outlet, said third cyclone separator being configured to separate media from the high-quality carbon slurry;
• withdrawing fluid separated from the high-quality carbon slurry through intake located at the junction of said cylindrical upper section and conical lower section of said third cyclone separator, and returning said fluid to the raw feed sump;
• directing water from said cyclone separators to a centrifuge having an outlet for producing a thickened concentrate and a concentrated waste;
• and
• retrieving a portion of the returned fluid concentrated with rare earth elements, lithium, and titanium.