Patent ID: 7507388

Claim:
A method for producing sodium chemicals from bicarbonate-including solutions obtained by solution mining of at least one of (a) trona, (b) nahcolite and (c) wegscheiderite reserves and lake waters including bicarbonates, comprising: purification and preheating; centrifuging; drying and packing; converting a portion of a purge taken away from a system to decahydrate and sesquicarbonate crystals with a reduced impurity content in a deca/sesqui crystallization process; recovering the crystals in an evaporation-stripping process, a light soda calcination process and a monohydrate crystallization process; wherein the deca/sesqui crystallization process includes one of (a) obtaining decahydrate crystals by caustic soda addition and crystallization at 15 to 30° or (b) obtaining sesquicarbonate crystals by crystallization at 30 to 70° C. without caustic soda addition and thus production of two different crystals within a single crystallizing system by changing the process parameters; and producing the caustic soda to be used in the deca/sesqui crystallization process by processing a portion of a purge taken away from the monohydrate centrifuging process together with milk of lime through a caustification-clarification and filtration processes.