摘要:
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 D50 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.
摘要:
A process for the beneficiation of trona includes supplying a trona feedstream that is crushed and dried. The trona is then separated into a first size fraction and a second size fraction. Impurities are removed from the first size fraction using at least one magnetic separator. The magnetic separator includes a plurality of stages. Each stage includes a conveyor system comprising a first end, a second end, and a conveyor belt. Each stage also includes a magnetic roller disposed at the second end of the conveyor system and a splitter disposed adjacent the second end of the system for separating a fraction of magnetic impurities from the trona to create a beneficiated fraction. At least one conveyor belt is deionized. Airborne dust particles are removed from an area surrounding at least one conveyor system.
摘要:
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 impurities, and the waste may contain sodium bicarbonate, sodium sesquicarbonate, and/or one or more sodium carbonate hydrates, such as decahydrate.
摘要:
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 impurities, and the waste may contain sodium bicarbonate, sodium sesquicarbonate, and/or one or more sodium carbonate hydrates, such as decahydrate.
摘要:
A process for beneficiation of trona includes supplying a trona feedstream that is crushed and dried. The trona is then separated into a first size fraction and a second size fraction. Impurities are removed from the first size fraction using at least one magnetic separator. The magnetic separator includes a plurality of stages. Each stage includes a conveyer system including a first end, a second end, and a conveyer belt. Each stage also includes a magnetic roller disposed at the second end of the conveyer system and a splitter disposed adjacent the second end of the conveyer system for separating a fraction of magnetic impurities from the trona to create a beneficiated fraction. At least one conveyer belt is deionized. Airborne dust particles are removed from an area surrounding at least one conveyer system.
摘要:
A process for beneficiation of trona includes supplying a trona feedstream that is crushed and dried. The trona is then separated into a first size fraction and a second size fraction. Impurities are removed from the first size fraction using at least one magnetic separator. The magnetic separator includes a plurality of stages. Each stage includes a conveyer system including a first end, a second end, and a conveyer belt. Each stage also includes a magnetic roller disposed at the second end of the conveyer system and a splitter disposed adjacent the second end of the conveyer system for separating a fraction of magnetic impurities from the trona to create a beneficiated fraction. At least one conveyer belt is deionized. Airborne dust particles are removed from an area surrounding at least one conveyer system.
摘要:
This invention provides a method for the production of dense soda ash by reacting sodium carbonate decahydrate with a light soda ash or soda ash fines at an elevated temperature to produce sodium carbonate monohydrate crystals, and drying the sodium carbonate monohydrate to produce dense soda ash.
摘要:
A process for recovery of alkali values from trona in which trona is dissolved, the sodium carbonate in the feed solution is converted to sodium bicarbonate by introducing carbon dioxide, sodium bicarbonate is crystallized and separated from a mother liquor, and sodium bicarbonate in the mother liquor is converted to sodium carbonate by introducing air to form a recirculating dissolving solution which is used to dissolve the trona.
摘要:
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.
摘要:
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.