Method for recovering valuable elements from precombustion coal-based materials

Patent metadata

Field	Value
Publication number	US-2020308667-A1
Application number	US-202016832157-A
Country	US
Kind code	A1
Filing date	Mar 27, 2020
Priority date	Apr 1, 2019
Publication date	Oct 1, 2020
Grant date	—

Abstract

A method for recovering valuable elements from pre-combustion coal-based materials includes the steps of grinding the materials to a predetermined size, roasting the ground materials at a temperature of 600° C.-700° C. for a predetermined residence time needed for mineral decomposition, submerging the roasted, ground materials in a solution of lixiviant, filtering the lixiviant solution to separate residual solids from a pregnant leach solution including the valuable elements and recovering and concentrating the valuable elements from the pregnant leach solution.

First claim

What is claimed:

1 . A method for recovering valuable elements from pre-combustion coal-based materials, comprising:
grinding the precombustion coal-based materials to a predetermined size; roasting the ground precombustion coal-based materials at a temperature of between 600° C.-700° C. for a predetermined residence time needed for mineral decomposition; submerging the roasted precombustion coal-based materials in a solution of a lixiviant; filtering the lixiviant solution to separate residual solids from a pregnant leach solution; and recovering and concentrating the valuable elements from the pregnant leach solution.

2 . The method of claim 1 , including using a lixiviant selected from a group of lixiviants consisting of ammonium sulfate, sulfuric acid, nitric acid, hydrochloric acid, mineral acid, organic acid, carboxyl acid and combinations thereof combinations thereof.

3 . The method of claim 2 , including using as the precombustion coal-based material a material selected from a group consisting of (a) run-of-mine material extracted from a coal seam, (b) associated mineral matter material within and immediately surrounding (roof and floor) a coal seam, (c) waste material generated during the mining process, (d) clean coal products produced in the process of upgrading coal in a processing plant or unit operation, (e) mixed-phase coal material, commonly referred to as ‘middlings’, (f) coarse coal waste from an active processing facility, (g) fine coal waste from an active processing facility, (h) coarse coal waste from legacy waste storage areas, (i) fine coal waste from a slurry impoundment, slurry cell, slurry pond or other fine waste storage facility and combinations thereof.

4 . The method of claim 3 , wherein the recovering and concentrating includes selectively precipitating the valuable elements.

5 . The method of claim 3 , wherein the recovering and concentrating includes solvent extracting the valuable elements.

6 . The method of claim 3 , wherein the recovering and concentrating includes selectively precipitating and solvent extracting the valuable elements.

7 . The method of claim 1 , including using as the precombustion coal-based material a material selected from a group consisting of (a) run-of-mine material extracted from a coal seam, (b) associated mineral matter material within and immediately surrounding (roof and floor) a coal seam, (c) waste material generated during the mining process, (d) clean coal products produced in the process of upgrading coal in a processing plant or unit operation, (e) mixed-phase coal material, commonly referred to as ‘middlings’, (f) coarse coal waste from an active processing facility, (g) fine coal waste from an active processing facility, (h) coarse coal waste from legacy waste storage areas, (i) fine coal waste from a slurry impoundment, slurry cell, slurry pond or other fine waste storage facility and combinations thereof.

8 . The method of claim 1 , wherein the recovering and concentrating includes selectively precipitating the valuable elements.

9 . The method of claim 1 , wherein the recovering and concentrating includes solvent extracting the valuable elements.

10 . The method of claim 1 , wherein the recovering and concentrating includes selectively precipitating and solvent extracting the valuable elements.

11 . A method for recovering valuable elements from pre-combustion coal-based materials, comprising:
grinding the precombustion coal-based materials to a predetermined size; adding a chemical additive to the ground precombustion coal-based materials to allow decomposition of the ground precombustion coal-based materials at a lower oxidation temperature; roasting the ground precombustion coal-based materials at a temperature of between 600° C.-700° C. for a predetermined residence time needed for mineral decomposition; submerging the roasted precombustion coal-based materials in a solution of a lixiviant; filtering the lixiviant solution to separate residual solids from a pregnant leach solution; and recovering and concentrating the valuable elements from the pregnant leach solution.

12 . The method of claim 11 , including using a lixiviant selected from a group of lixiviants consisting of ammonium sulfate, sulfuric acid, nitric acid, hydrochloric acid, mineral acid, organic acid, carboxyl acid and combinations thereof.

13 . The method of claim 12 , including using as the precombustion coal-based material a material selected from a group consisting of (a) run-of-mine material extracted from a coal seam, (b) associated mineral matter material within and immediately surrounding (roof and floor) a coal seam, (c) waste material generated during the mining process, (d) clean coal products produced in the process of upgrading coal in a processing plant or unit operation, (e) mixed-phase coal material, commonly referred to as ‘middlings’, (f) coarse coal waste from an active processing facility, (g) fine coal waste from an active processing facility, (h) coarse coal waste from legacy waste storage areas, (i) fine coal waste from a slurry impoundment, slurry cell, slurry pond or other fine waste storage facility and combinations thereof.

14 . The method of claim 13 , wherein the recovering and concentrating includes selectively precipitating the valuable elements.

15 . The method of claim 13 , wherein the recovering and concentrating includes solvent extracting the valuable elements.

16 . The method of claim 13 , wherein the recovering and concentrating includes selectively precipitating and solvent extracting the valuable elements.

17 . The method of claim 11 , including using as the precombustion coal-based material a material selected from a group consisting of (a) run-of-mine material extracted from a coal seam, (b) associated mineral matter material within and immediately surrounding (roof and floor) a coal seam, (c) waste material generated during the mining process, (d) clean coal products produced in the process of upgrading coal in a processing plant or unit operation, (e) mixed-phase coal material, commonly referred to as ‘middlings’, (f) coarse coal waste from an active processing facility, (g) fine coal waste from an active processing facility, (h) coarse coal waste from legacy waste storage areas, (i) fine coal waste from a slurry impoundment, slurry cell, slurry pond or other fine waste storage facility and combinations thereof.

18 . The method of claim 11 , wherein the recovering and concentrating includes selectively precipitating the valuable elements.

19 . The method of claim 11 , wherein the recovering and concentrating includes solvent extracting the valuable elements.

20 . The method of claim 11 , wherein the recovering and concentrating includes selectively precipitating and solvent extracting the valuable elements.

Assignees

• Univ Kentucky Res Found

Inventors

• Honaker Rick
• Zhang Wencai

Classifications

• Y02P10/20

  Recycling · CPC title

• C22B3/06

  in inorganic acid solutions {, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions} · CPC title

• C22B3/44

  by chemical processes (treatment or purification of solutions by liquid-liquid extraction C22B3/26, by ion-exchange extraction C22B3/42) · CPC title

• C22B1/02 Primary

  Roasting processes (C22B1/16 takes precedence) · CPC title

• C22B59/00

  Obtaining rare earth metals · CPC title