System and method for precipitating salts
AssigneeUnited States Filter Corporation
InventorsThomas Anthony Pecoraro, Steven Oshen
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Abstract
A system and method for producing salts using a crystallizer with an integrated column is disclosed. In the column, liquid, containing one reactant, absorbs a second reactant, from the gas stream. The second reactant reacts with the first reactant to produce salt. Liquid leaving the column and rich in salt, collects in the crystallizer. Conditions within the crystallizer promote nucleation and crystal growth. A recirculation system withdraws a portion of liquid from the crystallizer for introduction into the column.
Claims35
A system for precipitating salt comprising:
- a column comprising at least one internal element positioned within the column;
- a crystallizer in communication with the column;
- at least one inlet in communication with the column and the crystallizer;
- and
- at least one salt outlet positioned at the bottom of the crystallizer,
- wherein the internal element comprises at least one tray having at least one downward sloping surface.
A system for precipitating sodium metabisulfite comprising:
- a crystallizer having at least one sodium metabisulfite outlet;
- at least one column in communication with the crystallizer;
- at least one internal element positioned within the column;
- and
- at least one sulfur dioxide inlet in communication with at least one of the column and the crystallizer,
- wherein the internal element comprises at least one tray having at least one downwardly sloping surface.
A system for precipitating sodium metabisulfite comprising;
- a crystallizer having at least one sodium metabisulfite outlet and an agitation-suspension system;
- at least one column in communication with the crystallizer;
- at least one internal element positioned within the column;
- at least one recirculation system in communication with the crystallizer and the column;
- at least one sodium alkali inlet in communication with the recirculation system;
- and
- at least one sulfur dioxide inlet in communication with at least one of the column and the crystallizer,
- wherein the internal element comprises at least one tray with at least one downward sloping surface.
A method for producing sodium metabisulfite comprising:
- introducing a gas stream comprising sulfur dioxide into a column;
- introducing a liquid stream comprising sodium sulfite and water into the column;
- absorbing at least a portion of the sulfur dioxide into the liquid stream;
- reacting at least a portion of the sulfur dioxide with at least a portion of the sodium sulfite to produce a sodium metabisulfite stream;
- evaporating at least a portion of the water from the liquid stream into the gas stream;
- precipitating sodium metabisulfite from the sodium metabisulfite stream in a crystallizer;
- and
- withdrawing a slurry of sodium metabisulfite from the bottom of the crystallizer,
- wherein the column and the crystallizer are operated at substantially the same temperature.
A system for precipitating salts comprising:
- a column having at least one internal element;
- a crystallizer in communication with the column;
- a recirculation system in communication with the crystallizer and the column;
- a mixing slurry tank in communication with the recirculation system and the column;
- at least one gas outlet positioned in the column;
- at least one salt outlet positioned in the crystallizer;
- a slurry of salt contained in the crystallizer having a substantially uniform pH;
- a liquid stream having a first reactant flowing substantially downwardly within the column;
- a gas stream having a second reactant flowing in the column and substantially countercurrently against the liquid stream;
- a first feed inlet in communication with the column supplying the first reactant;
- and
- a second feed inlet in communication with the mixing slurry tank supplying a third reactant.
Dependencies are inferred from the claim text.