# US 7,611,208 B2 · Methods for constructing underground borehole configurations and related solution mining methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,611,208 B2 - Document ID: US7611208B2 - Status: Granted - Kind: B2 - Application number: 11/206,659 - Filed: 2005-08-17 - Published: 2006-02-23 - Granted: 2009-11-03 - Earliest claimed: 2004-08-17 - Assignees: Sesqui Mining, LLC - Inventors: Roger L. Day; James A. Herickhoff - Web page: https://patentgrep.com/patent/US7611208B2 ## CPC - E21B 7/00: Special methods or apparatus for drilling - C01D 7/00: Carbonates of sodium, potassium or alkali metals in general - C01D 7/126: {Multi-step processes, e.g. from trona to soda ash} - E21B 17/00: Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; {Cables;} Casings; Tubings - E21B 33/12: Packers; Plugs (used for cementing E21B33/134, E21B33/16) - E21B 33/13: Methods or devices for cementing, for plugging holes, crevices or the like - E21B 43/281: {using heat} - E21B 43/30: Specific pattern of wells, e.g. optimising the spacing of wells - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - C01D: COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts of peroxyacids C01B15/00; sulfides C01B17/22; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds other than ammonia and cyanogen, containing nitrogen and other non-metals C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; phosphides C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; cyanides C01C3/08; salts of cyanic acid C01C3/14; salts of cyanamide C01C3/16; thiocyanates C01C3/20) ## Abstract Disclosed are methods for solution mining of evaporite minerals, such as trona, comprising drilling an access well and at least two lateral boreholes; injecting a fluid; circulating the fluid through the lateral boreholes with a controlled fluid flow; and collecting a pregnant solution. Also disclosed are methods of solution mining that include injecting an aqueous solution into an underground trona cavity at a temperature sufficient to maintain at least a portion of the solution in the cavity in the Wegscheiderite solid phase region; removing aqueous solution from the cavity; and recovering alkaline values from the removed aqueous solution. Also disclosed are methods of solution mining that include injecting an aqueous solution into an underground trona cavity; removing aqueous solution from the cavity, wherein the temperature of the removed aqueous solution is at about the TWA point temperature; and recovering alkaline values from the removed aqueous solution. ## Claims ### Claim 1 A method of solution mining of trona, comprising: a. injecting an aqueous solution into an underground cavity comprising trona to dissolve the trona; b. removing aqueous solution from the cavity, wherein the temperature of the removed aqueous solution is at about the TWA point temperature in the range of 90° C. to 145° C.; and c. recovering alkaline values from the removed aqueous solution, wherein the aqueous solution comprises condensed steam produced by evaporation of water from a solution to produce sodium products. ### Claim 2 (depends on 1) The method of claim 1, wherein the sodium products are selected from the group consisting of sodium sesquicarbonate, sodium bicarbonate, sodium carbonate monohydrate and anhydrous sodium carbonate. ### Claim 3 (depends on 1) The method of claim 1, wherein the step of recovering comprises recovering sodium carbonate monohydrate by evaporating water from the removed aqueous solution to produce steam and condensing the steam. ### Claim 4 (depends on 3) The method of claim 3, wherein the condensed steam in the aqueous solution is the steam condensed by the step of recovering. ### Claim 5 (depends on 1) The method of claim 1, wherein the removed solution is enriched in NaHCO3 and Na2CO3. ### Claim 6 (depends on 1) The method of claim 1, wherein the removed solution is treated to form sodium bicarbonate, sodium sesquicarbonate, sodium carbonate monohydrate and anhydrous sodium carbonate. ### Claim 7 (depends on 6) The method of claim 6, wherein the removed solution is treated to form sodium bicarbonate by carbonating the removed solution. ### Claim 8 (depends on 6) The method of claim 6, wherein the removed solution is treated to form sodium sesquicarbonate. ### Claim 9 (depends on 6) The method of claim 6, wherein the step of treating comprises a step selected from the group consisting of cooling, evaporative crystallization and combinations thereof. ### Claim 10 (depends on 6) The method of claim 6, further comprising recovering sodium carbonate monohydrate from the removed solution after the removed solution is treated. ### Claim 11 (depends on 10) The method of claim 10, further comprising a step prior to recovering sodium carbonate monohydrate selected from the group consisting of fortification, steam stripping, evaporation, hydroxide process and sodium carbonate decahydrate process. ### Claim 12 (depends on 1) The method of claim 1, further comprising introducing Ca(OH)2 to the aqueous solution, whereby CaCO3 is formed and settles from the aqueous solution in the cavity. ### Claim 13 (depends on 1) The method of claim 1, further comprising introducing Ca(OH)2 to the removed aqueous solution, whereby CaCO3 is formed and settles from the aqueous solution. ### Claim 14 (depends on 13) The method of claim 13, further comprising introducing the CaCO3 into an underground cavity. ### Claim 15 (depends on 1) The method of claim 1, wherein during the dissolution of trona, Wegscheiderite and/or nahcolite are precipitated from the mining solution in the cavity and wherein the method is conducted until the cavity becomes effectively depleted of trona, further comprising: a. injecting an aqueous solution in the cavity comprising precipitated Wegscheiderite and/or nahcolite to dissolve the Wegscheiderite and/or nahcolite; b. removing aqueous solution from the cavity; and c. recovering alkaline values from the removed aqueous solution. ### Claim 16 (depends on 15) The method of claim 15, wherein the temperature of the removed aqueous solution is above the temperature at which sodium decahydrate can exist. ### Claim 17 (depends on 15) The method of claim 15, wherein the temperature of the removed aqueous solution is within the Wegscheiderite solid phase region. ### Claim 18 The method of c1aim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 75% of maximum solubility. ### Claim 19 (depends on 1) The method of claim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 80% of maximum solubility. ### Claim 20 (depends on 1) The method of claim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 85% of maximum solubility. ### Claim 21 (depends on 1) The method of claim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 90% of maximum solubility. ### Claim 22 (depends on 1) The method of claim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 95% of maximum solubility. ### Claim 23 (depends on 1) The method of claim 1, wherein the sodium bicarbonate and sodium carbonate concentrations in the removed aqueous solution are at greater than about 99% of maximum solubility. ### Claim 24 (depends on 1) The method of claim 1, wherein the temperature of the removed aqueous solution is in the range of about 115° C. to about 120° C. ### Claim 25 The method of c1aim 1, wherein the temperature of the removed aqueous solution is in the range of about 110° C. to about 145° C.