Method for continuous monitoring and optimization of recovery process

Abstract

Methods and apparatus are described herein for recovering an element of interest from an aqueous source. Methods described herein include measuring a first conductivity of a first aqueous material using a conductivity sensor; performing an operation on the first aqueous material to change a concentration of an element of interest of the first aqueous material and yield a second aqueous material; measuring a second conductivity of the second aqueous material using a conductivity sensor; comparing the first conductivity, or a first value of a variable derived from the first conductivity, with the second conductivity, or with a second value of the variable derived from the second conductivity; and modifying a parameter of the operation based on the comparison. Methods are also described herein for recovery of elements of interest from aqueous sources using simulated moving beds processes.

We claim: 
     
         1 . A method, comprising:
 measuring a first conductivity of a first aqueous material using a conductivity sensor;   performing an operation on the first aqueous material to change a concentration of an element of interest of the first aqueous material and yield a second aqueous material;   measuring a second conductivity of the second aqueous material using a conductivity sensor;   comparing the first conductivity, or a first value of a variable derived from the first conductivity, with the second conductivity, or with a second value of the variable derived from the second conductivity; and   modifying a parameter of the operation based on the comparison.   
     
     
         2 . The method of  claim 1 , wherein the variable is total dissolved solids (TDS) or a value derived from TDS, and further comprising determining a first TDS based on the first conductivity measurement, determining a second TDS based on the second conductivity measurement, or both. 
     
     
         3 . The method of  claim 1 , wherein modifying the parameter includes modifying a flow rate of the first aqueous material, the second aqueous material, or both. 
     
     
         4 . The method of  claim 1 , wherein performing the operation includes extracting the element of interest, using a direct extraction method, from the first aqueous material to yield the second aqueous material, wherein the direct extraction method includes capturing the element of interest using a media selective for the element of interest, or an electrochemical process, or both. 
     
     
         5 . The method of  claim 1 , wherein performing the operation includes using the first aqueous material to release the element of interest from a selective media to yield the second aqueous material. 
     
     
         6 . The method of  claim 1 , wherein performing the operation includes removing an impurity distinct from the element of interest from the first aqueous material. 
     
     
         7 . The method of  claim 1 , wherein performing the operation includes concentrating the first aqueous material. 
     
     
         8 . The method of  claim 1 , wherein the operation is a first operation, and further comprising:
 performing a second operation on the second aqueous material, or on an aqueous material derived from the second aqueous material, to change a concentration of an element of interest and yield a third aqueous material; and   measuring a third conductivity of the third aqueous material using a conductivity sensor.   
     
     
         9 . The method of  claim 8 , wherein the second operation is performed on the second aqueous material, and the method includes comparing a third value of the variable derived from the third conductivity with the second value of the variable, the method further comprising modifying a parameter of the second operation based on the comparison of the second value with the third value. 
     
     
         10 . The method of  claim 8 , wherein the second operation is performed on the aqueous material derived from the second aqueous material, and the aqueous material derived from the second aqueous material is a fourth aqueous material, the method further comprising:
 measuring a fourth conductivity of the fourth aqueous material;   comparing the third value of the variable derived from the third conductivity with a fourth value of the variable derived from the fourth conductivity; and   modifying a parameter of the second operation based on the comparison of the third and fourth values.   
     
     
         11 . The method of  claim 1 , wherein the first conductivity and the second conductivity are measured using the same conductivity sensor. 
     
     
         12 . The method of  claim 1 , wherein the first and second conductivity are measured repeatedly and the variable represents a TDS trend. 
     
     
         13 . The method of  claim 1 , wherein the element of interest is an element from the group consisting of lithium, manganese, nickel, and cobalt. 
     
     
         14 . The method of  claim 1 , further comprising repeatedly measuring at least one of the first conductivity and the second conductivity to yield a plurality of measurements, and modifying the operation parameter based on each measurement of the plurality of measurements. 
     
     
         15 . The method of  claim 14 , further comprising determining a value of the operation parameter for which the first value of the variable, the second value of the variable, or both reaches an extremum. 
     
     
         16 . A system for recovering an element of interest from an aqueous material, the system comprising:
 an extraction stage;   a processing stage downstream of the extraction stage; and   one or more conductivity sensors coupled to at least one of the extraction and processing stages and configured to measure a first conductivity of a first aqueous material and a second conductivity of a second aqueous material of said at least one stage,   one or more controllers configured to
 compare the first conductivity, or a first value of a variable derived from the first conductivity, with the second conductivity, or with a second value of the variable derived from the second conductivity; and 
 modify a parameter of the at least one stage based on the comparison. 
   
     
     
         17 . The system of  claim 16 , wherein the controller is configured to calculate, from the first and/or second conductivity, total dissolved solids of the first and/or second aqueous material or concentration of an first and/or second. 
     
     
         18 . The system of  claim 16 , wherein the controller is configured to modify a flow rate of the first aqueous material, the second aqueous material, or both 
     
     
         19 . The system of  claim 16 , wherein the extraction stage is configured to extract an element of interest from an aqueous source into a withdrawal medium to yield a depleted lithium stream and to recover the element of interest from the withdrawal medium using an eluent to yield a lithium intermediate; wherein the first aqueous material is the aqueous source and the second aqueous material is the lithium depleted stream and/or wherein the first aqueous material is the eluent and the second aqueous material is the lithium intermediate. 
     
     
         20 . The system of  claim 16 , wherein the processing stage configured to receive an input stream derived from the extraction stage and to yield a product stream; and wherein the first aqueous material is the input stream and the second aqueous material is the product stream.