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.
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.
A pin-and-collet assembly, a longwall shearer comprising a ranging arm attached to a lifting bracket with such assembly, a method for the secure fastening of one piece to another, such as securely fastening the ranging arm to the lifting bracket of a longwall shearer using such assembly as a bushing, and a method for longwall mining of ore, such as trona, using such longwall shearer. This assembly is easy to install, does not have to be tightened during longwall operation of an ore panel, and is also demountable when it is time to stop the longwall mining operation and time to remove/replace the ranging arm for maintenance and/or when the end of the ore panel is reached.
E21C 35/00 - Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups , or
F16B 17/00 - Fastening means without screw-thread for connecting constructional elements or machine parts by a part of or on one member entering a hole in the other
F16B 5/02 - Joining sheets or plates to one another or to strips or bars parallel to them by means of fastening members using screw-thread
E21C 27/02 - Machines which completely free the mineral from the seam solely by slitting
E21C 27/34 - Machine propelled along the working face by cable or chain
F16B 13/08 - Dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose with parts gripping in the hole or behind the reverse side of the wall after inserting from the front with separate gripping parts moved into their final position in relation to the body of the device without further manual operation
F16B 13/06 - Dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose with parts gripping in the hole or behind the reverse side of the wall after inserting from the front combined with expanding sleeve
F16B 29/00 - Screwed connection with deformation of nut or auxiliary member while fastening
A particulate sodium bicarbonate product with an excellent flowability characterized by an angle of repose less than 30 degrees. An angle of repose of less than 27.5 is particularly good. The product is preferably in the form of ovoid or spherical particles, in that the particles have a mean axial ratio of at least 0.5. In some embodiments, the sodium bicarbonate product has a smooth particle surface in which less than 75% of the particle surface is covered with spikes. The particles may have a mean diameter D 50 of at least 75 microns but less than 300 microns. The particulate sodium bicarbonate product comprises inorganic and organic impurities embedded in its polycrystalline structure, for example at least 75 ppm TOC; or at least 30 ppm Ca; or from 1 to 18 ppm Mg; or more than 0.6 g/kg NaCl; and/or from 100 to less than 500 ppm Si. A process for manufacturing such product, and its use for the treatment of pollutants in gases such as removal of acid gas.
C01D 7/10 - Preparation of bicarbonates from carbonates
B01D 53/02 - Separation of gases or vapoursRecovering vapours of volatile solvents from gasesChemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography
B01J 20/04 - Solid sorbent compositions or filter aid compositionsSorbents for chromatographyProcesses for preparing, regenerating or reactivating thereof comprising inorganic material comprising compounds of alkali metals, alkaline earth metals or magnesium
5.
Use of ventilation air methane exhausted during mining of non-combustible ore in a surface appliance
Utilization of mine methane produced by mining a non-combustible ore, such as trona, as an energy source for heat, steam, and/or power generation. Such utilization is beneficial for a surface appliance which is close to surface outlet(s) of mine methane recovery system(s). A method for reducing greenhouse gas emissions generated during mining of a non-combustible ore uses the combustion of co-produced mine methane. The mine methane is recovered in a mine ventilation air exhaust with very low methane content, and may be additionally recovered in a drainage gas, such as gob gas, with much higher methane content. The surface appliance may be selected from the group consisting of calciner, dryer, boiler, kiln, furnace, engine, turbine, power generation unit, co-generation unit, and any combinations thereof. Benefits may include reduction in energy purchases, reduction in greenhouse emissions, and/or gain through sale of carbon credits to the carbon market by registering carbon reductions.
F23G 7/06 - Methods or apparatus, e.g. incinerators, specially adapted for combustion of specific waste or low grade fuels, e.g. chemicals of waste gases or noxious gases, e.g. exhaust gases
6.
Impurities removal from waste solids in the production of soda ash, sodium bicarbonate and/or other derivatives
A method for removing impurities from a waste solid to provide at least a portion of a suitable crystallizer feed to a process for making crystalline sodium carbonate, bicarbonate, and/or other derivatives. The method comprises: contacting the waste solid with a leach solution to dissolve at least one impurity and dissolving the resulting leached residue. Leaching may include heap percolation. The leach solution may comprise a crystallizer purge liquor, a process waste effluent, a mine water, or mixtures thereof. The method may further comprise adding a magnesium compound to the resulting leached residue during or after its dissolution to remove another impurity. The waste solid preferably comprises a pond solid containing such impurities. The pond solid may be recovered from a pond receiving crystallizer purge liquor(s) and/or other process waste effluent(s). The pond solid may contain sodium carbonate, any hydrate thereof, sodium bicarbonate, and/or sodium sesquicarbonate. The impurities to be removed may comprise sodium chloride, sodium sulfate, silicates, and/or organics.
A method for removing impurities from a waste solid to provide at least a portion of a suitable crystallizer feed to a process for making crystalline sodium carbonate, bicarbonate, and/or other derivatives. The method comprises: contacting the waste solid with a leach solution to dissolve at least one impurity and dissolving the resulting leached residue. Leaching may include heap percolation. The leach solution may comprise a crystallizer purge liquor, a process waste effluent, a mine water, or mixtures thereof. The method may further comprise adding a magnesium compound to the resulting leached residue during or after its dissolution to remove another impurity. The waste solid preferably comprises a pond solid containing such impurities. The pond solid may be recovered from a pond receiving crystallizer purge liquor(s) and/or other process waste effluent(s). The pond solid may contain sodium carbonate, any hydrate thereof, sodium bicarbonate, and/or sodium sesquicarbonate. The impurities to be removed may comprise sodium chloride, sodium sulfate, silicates, and/or organics.
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.
A magnesium treatment for removing water-soluble impurities in a process for making crystalline sodium carbonate, bicarbonate, or sulfite. A waste comprising such impurities is treated with a magnesium compound to form water-insoluble matter which is removed to form a purified solution. The treatment may be performed on a solution which contains the waste and optionally dissolved calcined trona. The purified solution may be used as a feedstock to form crystalline soda ash, and/or used as a reactant to produce crystalline sodium sulfite or bicarbonate via reaction with SO2 or CO2. In preferred embodiments, the waste may comprise a purge or weak liquor, a reclaimed solid, or combinations thereof. The water-soluble impurities may be silicates and/or foam-causing organics, and the waste may contain sodium bicarbonate, sodium sesquicarbonate, and/or one or more sodium carbonate hydrates, such as decahydrate.
2. In preferred embodiments, the waste may comprise a purge or weak liquor, a reclaimed solid, or combinations thereof. The water-soluble impurities may be silicates and/or foam-causing impurities, and the waste may contain sodium bicarbonate, sodium sesquicarbonate, and/or one or more sodium carbonate hydrates, such as decahydrate.
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.
A method of producing crystals of crystallizable mineral salt comprises introducing an effluent comprising a dissolved crystallizable mineral salt at a temperature higher than the mineral salt crystallization temperature to a crystallization pond area to provide a pond solution; cooling the pond solution to provide cooling crystallization promoting conditions effective to form a crystalline mineral salt deposit; stopping the flow of the effluent; draining remaining spent liquor to a liquor pond area; and recovering the deposit. Cooling the pond solution may comprise exposure to cool ambient temperatures which are lower than the crystallization temperature. Preferably, the mineral salt includes or is sodium carbonate decahydrate; the pond solution comprises less than 10 % NaCl; and/or the decahydrate deposit is sent or recycled to a soda ash plant. The deposit thus formed by cooling crystallization has a higher purity, lower hardness, and/or lower density than a deposit formed by evaporative crystallization.
A sodium sulfite liquor is formed by reacting sodium carbonate with sulfur dioxide. A CO2 byproduct may be removed from the formed liquor by injecting a stripping gas (e.g., steam and/or air) into the liquor, either into a transfer pipe or into a tank that is vented; by increasing the liquor temperature; and/or by reducing the liquor pressure. The decarbonated sodium sulfite liquor with a reduced carbon dioxide content is introduced into a crystallizer connected to a circulation loop comprising a heater and/or a filter. Additional decarbonation by heating, stripping and/or depressurization of the liquor may be carried out in a circulation loop connected to the crystallizer. The condensing side of the heater may be vented. The flow rate of the circulation loop and/or heater temperature differences may be monitored. Additional CO2 may be vented from a holding tank to maintain circulation loop flows and heater temperature differences.
Methods for heating a solid material comprising a granular material are provided. Dust is removed from the granular material before it is heated. The dust is injected into the exhaust gas from the heater. The heated dust is recovered and combined with the heated granular material.
Methods for heating a solid material comprising a granular material are provided. Dust is removed from the granular material before it is heated. The dust is injected into the exhaust gas from the heater. The heated dust is recovered and combined with the heated granular material.
A method of removing SO3 from a flue gas stream includes providing a reaction compound selected from the group consisting of sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, and mixtures thereof. The reaction compound is injected into the flue gas stream. The temperature of the flue gas is between about 500~ F and about 850~ F. The reaction compound is maintained in contact with the flue gas for a time sufficient to react a portion of the reaction compound with a portion of the SO3 to reduce the concentration of the SO3 in the flue gas stream.
A method of removing SO3 from a flue gas stream includes providing a reaction compound selected from the group consisting of sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, and mixtures thereof. The reaction compound is injected into the flue gas stream. The temperature of the flue gas is between about 500° F and about 850° F. The reaction compound is maintained in contact with the flue gas for a time sufficient to react a portion of the reaction compound with a portion of the SO3 to reduce the concentration of the SO3 in the flue gas stream.
A method of removing SO3 from a flue gas stream includes providing a reaction compound selected from the group consisting of sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, and mixtures thereof. The reaction compound is injected into the flue gas stream. The temperature of the flue gas is between about 500°F and about 850°F. The reaction compound is maintained in contact with the flue gas for a time sufficient to react a portion of the reaction compound with a portion of the SO3 to reduce the concentration of the SO3 in the flue gas stream.
A method of removing SO3 from a flue gas stream having increased amounts of SO3 formed by a NOx removal system, includes injecting a sorbent composition into the flue gas stream. The sorbent composition includes an additive and a sodium sorbent such as mechanically refined trona or sodium bicarbonate. The additive is selected magnesium carbonate, calcium carbonate, magnesium hydroxide, calcium hydroxide, and mixtures thereof. The concentration of the SO3 in the flue gas stream is reduced and the formation of a liquid phase NaHSO4 reaction product is minimized.
A method of removing SO2 from a flue gas stream including SO2 includes providing a source of trona and injecting the trona into the flue gas stream. The temperature of the flue gas is between about 600° F and about 900° F. The trona is maintained in contact with the flue gas for a time sufficient to react a portion of the trona with a portion of the SO2 to reduce the concentration of the SO2 in the flue gas stream.
