US 12,655,040 B2 · Crystallization of salts from high pressure reverse osmosis concentrate

Abstract

Zero liquid discharge systems, processes, and techniques for treating a saltwater without evaporative crystallization. The saltwater is treated by a fluidic circuit comprising a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, a cooling crystallizer, and a solids-liquid separator. The saltwater is first concentrated by the HPRO unit to produce an HPRO brine, which is subsequently cooled to a designated crystallization temperature by the cooling crystallizer. The cooling crystallizer crystallizes salt crystals from the cooled HPRO brine and produces a salt-diminished brine. The solids-liquid separator separates the salt-diminished brine from the salt crystals. The salt-diminished brine from the solids-liquid separator is returned to the HPRO unit for further treatment, which allows additional salts to be crystallized from the returned salt-diminished brine.

Claims17

Dependent claims

A process for crystallizing solid salts from a saltwater, the process comprising:

(a) applying reverse osmosis at a hydraulic pressure of at least 1,500 psi to a fluid comprising the saltwater and a returned salt-diminished brine from treating the saltwater with the process to produce a permeate and a concentrated brine from the fluid;
(b) cooling the concentrated brine to crystallize the solid salts and to produce a salt-diminished brine from the concentrated brine, wherein the salt-diminished brine comprises salts identical to, and lower in concentration than, salts of the concentrated brine;
(c) separating at least some of the solid salts and the salt-diminished brine from each other;
and
(d) returning, without further reduction in salt concentration, at least some of the separated salt-diminished brine as the returned salt-diminished brine.

2 more elements

A system for crystallizing solid salts from a saltwater, the system comprising:

(a) a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, the HPRO unit comprising an inlet for receiving a fluid comprising the saltwater and a returned salt-diminished brine resulting from treating the saltwater by the system, a permeate outlet for outputting a permeate, and a brine outlet for outputting a concentrated brine;
(b) a cooling crystallizer fluidly coupled to the brine outlet to receive the concentrated brine, wherein the cooling crystallizer is configured to cool the concentrated brine to crystallize the solid salts from the concentrated brine and to produce a salt-diminished brine comprising salts identical to, and lower in concentration than, salts of the concentrated brine;
(c) a solids-liquid separator fluidly coupled to the cooling crystallizer to receive the solid salts and the salt-diminished brine, the solids-liquid separator configured to separate at least some of the solid salts from the salt-diminished brine;
and
(d) a return conduit fluidly coupling the solids-liquid separator to the inlet of the HPRO unit for returning, without further reduction in salt concentration, at least a portion of the salt-diminished brine as the returned salt-diminished brine.

2 more elements

Dependencies are inferred from the claim text.

Crystallization of salts from high pressure reverse osmosis concentrate

Life of this patent

Crystallization of salts from high pressure reverse osmosis concentrate

Life of this patent

Abstract

Claims17