Solvay Chemicals Gmbh

Solvay Sa

Larry C Refsdal

Ronald O Hughes

Joseph A Vendetti

Jean-Paul Detournay

Alain Vandendoren

Beatrice C Ortego

David M Hansen

Todd Brichacek

Justin T Patterson

John Kolesar

Ryan Schmidt

Herve Cuche

Michael C Montoya

Matteo Paperini

Bryan M Mortimer

Richard A Hodgson

Hervé Cuche

Beatrice Ortego

Justin Patterson

A method for in situ solution mining of a mineral from an underground evaporite stratum using a set of wells in fluid communication with at least one mineral cavity with some wells operated in solvent injection mode and other wells operated in brine production mode and optionally with some inactive wells, comprising switching the operation mode of one or more wells. The evaporite mineral preferably comprises trona. The at least one cavity may be formed by directionally drilled uncased boreholes or by lithological displacement of the evaporite stratum at a weak interface with an underlying insoluble stratum by application of a lifting hydraulic pressure to create an interfacial gap. The extracted brine can be processed to make valuable products such as soda ash and/or any derivatives thereof. This method can provide more uniform dissolution of mineral in the cavity, minimize flow channeling, minimize sodium bicarbonate blinding for solution mining of incongruent trona ore, and/or may avoid uneven deposit of insolubles.

Multi-well solution mining exploitation of an evaporite mineral stratum

Batch initiation and/or exploitation phases of in situ solution mining of a mineral from an underground evaporite mineral stratum. The initiation phase may comprise a lifting step which employs a lithological displacement (lifting) of this stratum from an underlying non-evaporite stratum with application at the strata interface of a lifting hydraulic pressure greater than overburden pressure by a solvent suitable to dissolve the mineral; a soaking step for dissolution of mineral upon contact with stationary solvent, and a brine extraction step. The method may further comprise one or more exploitation phases carried out after the initiation phase. The exploitation phase may comprise a partial filing or filling step with the same solvent or different solvent than during lifting, another soaking step, and another brine extraction step. The lifting, cavity partial filing/filling, and brine extraction steps are being discontinuous. The evaporite mineral stratum preferably comprises trona.

Batch solution mining using lithological displacement of an evaporite mineral stratum and mineral dissolution with stationary solvent

In-situ solution mining method of an ore bed, particularly containing trona, which comprises exposing to a solvent an ore region inside a borehole drilled in the ore, and dissolving a desired solute within the exposed region to provide a liquor and create a voided 'undercut', such undercutting making the ore susceptible to gravitational loading and crushing. Unexposed ore falls into the undercut by gravity without breaking the ore roof resulting in exposure of fresh ore to the solvent and in preventing solvent exposure to contaminating material near the roof. The desired solute is eventually dissolved away in the entire bed from its floor up to its roof. Solvent injection may be delivered through a conduit positioned inside the borehole, and may be moved by retracting or perforating the conduit. The method may employ an advancing undercut initiated up-dip and traveling down-dip, or a retreating undercut initiated down-dip and traveling up-dip.

Traveling undercut solution mining systems and methods

A method for co-extracting non-combustible ore (e.g., trona) and methane from an underground formation comprising at least one methane-bearing layer and a non-combustible ore bed having a rock roof, comprising:

Mining method for co-extraction of non-combustible ore and mine methane

Growing community of inventors

Green River, WY, United States of America

Larry C Refsdal