Dewatering system for increasing the combined cycle efficiency of a coal powerplant

Abstract

A coal treatment system, comprising an advanced coal treatment stage configured to produce ultra clean coal, wherein the stage comprises a leaching agent treatment system configured to remove a mineral from the coal and form a wastewater stream; and a dewatering system in fluid communication with the leaching agent treatment system and configured to reduce a concentration of a contaminant in the wastewater stream, wherein the dewatering system comprises a reverse osmosis membrane in fluid communication with the wastewater stream.

1 . A coal treatment system, comprising:
 an advanced coal treatment stage configured to produce ultra clean coal, wherein the stage comprises   a leaching agent treatment system configured to remove a mineral from the coal and form a wastewater stream; and   a dewatering system in fluid communication with the leaching agent treatment system and configured to reduce a concentration of a contaminant in the wastewater stream, wherein the dewatering system comprises a reverse osmosis membrane in fluid communication with the wastewater stream.   
     
     
         2 . The system of  claim 1 , wherein the reverse osmosis membrane is configured to generate a permeate stream having a reduced contaminant concentration and a concentrate stream having an increased contaminant concentration compared to the contaminant concentration of the wastewater stream. 
     
     
         3 . The system of  claim 1 , wherein the contaminant comprises the leaching agent, the mineral, or a combination comprising at least one of the foregoing. 
     
     
         4 . The system of  claim 1 , wherein the reverse osmosis membrane comprises cellulose acetate, cellulose nitrate, polyamide, polyethersulfone, or a combination comprising at least one of the foregoing. 
     
     
         5 . The system of  claim 1 , further comprising a filter system disposed in fluid communication between the leaching agent treatment system and the dewatering system, wherein the filtering system is configured to remove a solid component from the wastewater stream. 
     
     
         6 . The system of  claim 1 , further comprising a coal gas turbine system in operative communication with the advanced coal treatment stage configured to combust the ultra clean coal and produce power. 
     
     
         7 . The system of  claim 1 , wherein the leaching agent comprises hydrofluoric acid, fluoride, nitric acid, ferric nitrate, or a combination comprising at least one of the foregoing. 
     
     
         8 . The system of  claim 1 , wherein the mineral comprises silicon, aluminum, iron, titanium, potassium, calcium, sodium, magnesium, barium, strontium, vanadium, copper, manganese, zirconium, zinc, cerium, or a combination comprising at least one of the foregoing. 
     
     
         9 . The system of  claim 1 , wherein the wastewater stream contaminant concentration has a total dissolved solids concentration of about 10,000 mg/L to about 60,000 mg/L. 
     
     
         10 . The system of  claim 1 , wherein the wastewater stream has a pH of about 0 to about 4. 
     
     
         11 . The system of  claim 3 , wherein the permeate stream has a total dissolved solids concentration of about 0.1 mg/L to about 10,000 mg/L. 
     
     
         12 . The system of  claim 3 , wherein the concentrate stream has a total dissolved solids concentration of about 8,000 mg/L to about 500,000 mg/L. 
     
     
         13 . The system of  claim 4 , wherein the permeate stream has a pH of about 4 to about 7. 
     
     
         14 . The system of  claim 4 , wherein the concentrate stream has a pH of about 0 to about 3. 
     
     
         15 . The system of  claim 1 , further comprising removing at least about 50 percent by volume of the water from the wastewater stream. 
     
     
         16 . The system of  claim 1 , wherein the pressure is about 1 MPa to about 12 MPa. 
     
     
         17 . The system of  claim 1 , wherein the pressure is about 7 MPa to about 12 MPa. 
     
     
         18 . The system of  claim 17 , further comprising removing at least about 80 percent by volume of the water from the wastewater stream.