Abstract: Crystal solids made via the continuous crystallization of a crude, concentrated aqueous feed solution are recovered as a crystalline solid product that is relatively free of impurities present in the crystallizer liquor. A portion of the withdrawn crystallizer slurry is concentrated in a first hydroclone, diluted with crystallizer feed solution, concentrated in a second hydroclone, and centrifuged and dried to recover the crystalline solid product.

Abstract: Sodium bicarbonate is produced by introducing solid sodium carbonate, sodium sesquicarbonate, and/or Wegscheider's salt into a reversion slurry, saturated with respect to bicarbonate and containing at least 10 wt. % solids, to effect rapid and complete conversion of the feed solids to crystalline sodium bicarbonate which is recovered from the slurry. Carbon dioxide is introduced into the reversion liquor to maintain its composition at a relatively constant value, preferably in a region of the Na.sub.2 CO.sub.3 --NaHCO.sub.3 --H.sub.2 O phase diagram that minimizes the equilibrium partial pressure of CO.sub.2 vapor above such liquor.

Abstract: A cyclic solution mining method that uses aqueous sodium hydroxide for recovering valuable alkali values, preferably as soda ash, from subterranean deposits of trona or nahcolite, even when such deposits are NaCl-contaminated. The aqueous sodium hydroxide mining solvent is generated via electrodialysis of a recirculating sodium chloride brine stream. Hydrogen chloride that is also generated in the cell's operation is neutralized with aqueous sodium carbonate, to regenerate sodium chloride brine that is recirculated to the electrodialysis cell as brine feed.

Abstract: Hot flue gas containing sulfur oxides is treated in a dry injection desulfurization process by injecting a dry particulate soda ash sorbent into the SO.sub.2 -contaminated gas stream, which must contain 0.5-10 wt % water and be at a temperature of 100.degree.-175.degree. C., and collecting the sorbent in a solids collection device like a baghouse filter. The dry soda ash sorbent is a porous sodium carbonate, derived from calcination of a NaHCO.sub.3 -containing compound, and must have a minimum surface area of at least 2 m.sup.2 /g and less than 10 wt % residual bicarbonate. In this process, at least 40% of the sorbent's sodium content is utilized in the desulfurization reaction, at a normalized stoichiometric ratio=1.

Abstract: Soda ash is prepared from dry-mined nahcolite ore by partially calcining the ore, dissolving the ore in aqueous solution, separating the resultant solution from the ore insolubles, crystallizing anhydrous sodium carbonate or sodium carbonate monohydrate, and recovering the crystallized sodium carbonate.

Abstract: YUtilization of a soda-type dry sorbent in a dry injection flue gas desulfurization process is increased, without sacrifice in the SO.sub.2 removal efficiency, by reinjecting a portion of the sorbent collected in the baghouse filter back into the hot flue gas stream along with fresh sorbent; the recycled sorbent is optionally cooled below the bag filter temperature prior to its reinjection.

Abstract: A method for recovering alkali values from subterranean deposits of trona ore associated with sodium chloride by contacting the trona with an aqueous mining solution containing sodium hydroxide and subsequently utilizing the alkali values contained in the resultant salt- and sodium carbonate-containing solution. The alkali values are preferably crystallized as substantially salt-free sodium carbonate monohydrate, which is dried to recover soda ash. The mother liquor containing all of the salt is then treated to prepare a dilute sodium hydroxide solution, which may be employed as aqueous mining solution in a cyclic method to recover additional alkali values from trona.

Abstract: Calcined trona and/or nahcolite bearing ore particles are separated into a plurality of fractions of relatively uniform particle size. Those calcined particles smaller than about 6.7 mm in size and larger than about 0.2 mm in size are passed through an electrostatic separator to obtain an ore concentrate containing a greater percentage of soda ash and a lesser percentage of insoluble impurities than were present in the ore; a middling fraction and an ore tailing fraction containing a lesser percentage of soda ash and a greater percentage of insoluble impurities than were present in the ore. The middling fraction may be recycled to increase the yield of ore concentrate. Calcined particles smaller than about 0.2 mm may be combined with the ore concentrate. The combined ore concentrate fraction may be marked as technical grade soda ash or used as a high grade feed to a monohydrate refining process.

Abstract: The storage level of ore, supplied by an overhead loader to a bin or pile in the form of large, dense, hard fragments, up to a foot or more in diameter, is measured and controlled by repetitively lowering a line carrying a weight, having a mass at least as great as the largest ore fragments, from above the stored mass to the surface of the stored mass and measuring the distance traveled by the weight. Feed of ore is automatically stopped when maximum allowable level of stored mass is detected. Measurement of ore level is accomplished by counting, during the lowering of the weight, the pulses generated by a pulse generator operated by the turning of a winch upon which the line is reeled. The contact of the lowered weight with the stored ore mass is detected by the slowing of the rate of pulse generation as the weight ceases falling under the influence of gravity and the winch therefore ceases turning.

Abstract: Method of preparing refined, dense soda ash from crude trona by calcining the crude trona to crude sodium carbonate, mixing the crude sodium carbonate with an aqueous solution of soda ash or water to form a substantially saturated crude sodium carbonate solution containing coarse and fine insolubles, clarifying the crude sodium carbonate solution, passing the clarified sodium carbonate solution upwardly through an expanded carbon bed to remove organic impurities, evaporating the carbon-treated sodium carbonate solution to crystallize sodium carbonate monohydrate crystals, separating the sodium carbonate monohydrate crystals and calcining them to dense soda ash.

Abstract: Process for producing high bulk density sodium carbonate monohydrate crystals from sodium carbonate solutions wherein the sodium carbonate monohydrate is crystallized in the presence of at least 30 parts per million soluble aluminum ions.

Abstract: Method for clarifying a carbonate process solution containing suspended insolubles which solution is used in the preparation of crystals selected from the group consisting of sodium bicarbonate, sodium sesquicarbonate, anhydrous sodium carbonate, and sodium carbonate monohydrate, which comprises dispersing in the carbonate process solution prior to crystallization a cationic flocculating agent comprising a substituted guar gum containing one quaternary ammonium group per 2 to 12 monosaccharide units to agglomerate the suspended insolubles so the suspended insolubles will readily settle out of the carbonate process solution.This invention relates to a process for clarifying a carbonate process solution used in the preparation of sodium bicarbonate, sodium sesquicarbonate, anhydrous sodium carbonate or sodium carbonate monohydrate crystals.

Abstract: This invention involves a process for producing high bulk density sodium carbonate from crude trona wherein sodium carbonate monohydrate purge streams containing high amounts of organic impurities are passed to an anhydrous crystallizer operated at temperatures above about 109.degree.C wherein anhydrous sodium carbonate crystals are formed having high bulk densities of about 60 to about 80 lbs/ft.sup.3.