Abstract: A process for treating wastewater or waste brines that include sodium and chloride ions. The waste brine is concentrated and thereafter directed to a Mirabilite crystallizer that produces hydrated sulfate salt crystals and a first solution. The hydrated crystals are melted to form an aqueous sulfate solution that is directed to a sodium sulfate crystallizer which produces sodium sulfate salt crystals. The first solution produced by the Mirabilite crystallizer is directed to a nanofiltration device which produces a permeate stream and a reject stream containing sulfate removed by the nanofiltration device. The permeate stream is directed to a sodium chloride crystallizer that produces sodium chloride salt crystals. The reject stream is recycled to the Mirabilite crystallizer.

Abstract: A process for treating wastewater or waste brines that include sodium and chloride ions. The waste brine is concentrated and thereafter directed to a Mirabilite crystallizer that produces hydrated sulfate salt crystals and a first solution. The hydrated crystals are melted to form an aqueous sulfate solution that is directed to a sodium sulfate crystallizer which produces sodium sulfate salt crystals. The first solution produced by the Mirabilite crystallizer is directed to a nanofiltration device which produces a permeate stream and a reject stream containing sulfate removed by the nanofiltration device. The permeate stream is directed to a sodium chloride crystallizer that produces sodium chloride salt crystals. The reject stream is recycled to the Mirabilite crystallizer.

Abstract: A process for treating wastewater or waste brines that include sodium and chloride ions. The waste brine is concentrated and thereafter directed to a Mirabilite crystallizer that produces hydrated sulfate salt crystals and a first solution. The hydrated crystals are melted to form an aqueous sulfate solution that is directed to a sodium sulfate crystallizer which produces sodium sulfate salt crystals. The first solution produced by the Mirabilite crystallizer is directed to a nanofiltration device which produces a permeate stream and a reject stream containing sulfate removed by the nanofiltration device. The permeate stream is directed to a sodium chloride crystallizer that produces sodium chloride salt crystals. The reject stream is recycled to the Mirabilite crystallizer.

Abstract: A process for treating wastewater or waste brines that include sodium and chloride ions. The waste brine is concentrated and thereafter directed to a Mirabilite crystallizer that produces hydrated sulfate salt crystals and a first solution. The hydrated crystals are melted to form an aqueous sulfate solution that is directed to a sodium sulfate crystallizer which produces sodium sulfate salt crystals. The first solution produced by the Mirabilite crystallizer is directed to a nanofiltration device which produces a permeate stream and a reject stream containing sulfate removed by the nanofiltration device. The permeate stream is directed to a sodium chloride crystallizer that produces sodium chloride salt crystals. The reject stream is recycled to the Mirabilite crystallizer.

Abstract: A process is described for recovering alkali-chloride and alkali-sulfate salts from a salt solution. The salt solution comprises alkali metal, chloride and sulfate ions and is directed to a hydrous salt crystallization unit which crystallizes hydrated sulfate salts that comprise sulfate and at least one alkali metal. A purged solution from the hydrous salt crystallization unit is directed to a chloride salt crystallization unit while the hydrated sulfate salt crystals are melted to form an aqueous sulfate solution which is directed to a sulfate crystallization unit. Anhydrous sulfate salts are crystallized from the aqueous sulfate solution to form sulfate salt crystals comprising sulfate and at least one alkali metal. In the chloride salt crystallization unit, chloride salt is crystallized to form chloride salt crystals. A purge from the chloride salt crystallization unit is directed to the hydrous salt crystallization unit.

Abstract: A process is described for recovering alkali-chloride and alkali-sulfate salts from a salt solution. The salt solution comprises alkali metal, chloride and sulfate ions and is directed to a hydrous salt crystallization unit which crystallizes hydrated sulfate salts that comprise sulfate and at least one alkali metal. A purged solution from the hydrous salt crystallization unit is directed to a chloride salt crystallization unit while the hydrated sulfate salt crystals are melted to form an aqueous sulfate solution which is directed to a sulfate crystallization unit. Anhydrous sulfate salts are crystallized from the aqueous sulfate solution to form sulfate salt crystals comprising sulfate and at least one alkali metal. In the chloride salt crystallization unit, chloride salt is crystallized to form chloride salt crystals. A purge from the chloride salt crystallization unit is directed to the hydrous salt crystallization unit.

Abstract: A method is provided for treating brine recovered from a coal seam gas operation. The process entails directing brine recovered from a coal seam gas operation to a mixed reactor and mixing an alkaline earth reagent with the brine. This results in the precipitation of alkaline earth salts and silica, which form alkaline earth salt crystals having silica adsorbed thereto. Thereafter, the alkaline earth salt crystals and adsorbed silica are directed to an evaporator that produces a concentrate having the alkaline earth salt crystals and adsorbed silica.

Abstract: A method is provided for treating brine recovered from a coal seam gas operation. The process entails directing brine recovered from a coal seam gas operation to a mixed reactor and mixing an alkaline earth reagent with the brine. This results in the precipitation of alkaline earth salts and silica, which form alkaline earth salt crystals having silica adsorbed thereto. Thereafter, the alkaline earth salt crystals and adsorbed silica are directed to an evaporator that produces a concentrate having the alkaline earth salt crystals and adsorbed silica.

Abstract: A process is provided for recovering sodium chloride crystals and sodium carbonate decahydrate crystals from a concentrated brine that results from a gas mining operation where gas and produced water is recovered and the produced water constitutes a brine. An initial pre-concentration process is carried out where the brine is concentrated and in the process carbon dioxide is removed from the brine and at least some sodium bicarbonate is converted to sodium carbonate. In one process, the concentrated brine is directed to a sodium chloride crystallizer where the brine is heated and further concentrated to form sodium chloride crystals which are separated from the brine to yield a product and wherein the resulting brine is termed a first mother liquor. The first mother liquor is then directed to a sodium carbonate decahydrate crystallizer where the first mother liquor is cooled and concentrated resulting in the formation of sodium carbonate decahydrate crystals and a second mother liquor.

Abstract: A process is provided for recovering sodium chloride crystals and sodium carbonate decahydrate crystals from a concentrated brine that results from a gas mining operation where gas and produced water is recovered and the produced water constitutes a brine. An initial pre-concentration process is carried out where the brine is concentrated and in the process carbon dioxide is removed from the brine and at least some sodium bicarbonate is converted to sodium carbonate. In one process, the concentrated brine is directed to a sodium chloride crystallizer where the brine is heated and further concentrated to form sodium chloride crystals which are separated from the brine to yield a product and wherein the resulting brine is termed a first mother liquor. The first mother liquor is then directed to a sodium carbonate decahydrate crystallizer where the first mother liquor is cooled and concentrated resulting in the formation of sodium carbonate decahydrate crystals and a second mother liquor.

Abstract: Heat transfer in non-turbulent highly viscous mixed-phase flowing streams can be improved by altering flow characteristics using spiral-shaped elements to eliminate boundary phenomena. The spiral-shaped element promotes helical or spiral flow paths to reduce or eliminate temperature gradients associated with laminar flow characteristics.

Abstract: Heat transfer in non-turbulent highly viscous mixed-phase flowing streams can be improved by altering flow characteristics using spiral-shaped elements to eliminate boundary phenomena. The spiral-shaped element promotes helical or spiral flow paths to reduce or eliminate temperature gradients associated with laminar flow characteristics.

Abstract: An apparatus for distributing a slurry comprising a first section having a dome or cone shape and a plurality of passageways, and a second flat section located below the first section and having a plurality of passageways. The apparatus is useful in distributing a slurry of ice and liquid to a freezing section of an ice crystallizer.

Abstract: A method for treating a mechanical pulp plant effluent waste stream by freezing the effluent stream and separating frozen product. The frozen product contains between about 50 to 150 ppm chemical oxygen demand (COD), and may be reclaimed.