System and a process for membrane filtration of a dispersion
AssigneeMD Foods amba
InventorsAksel Saugmann, Erik Krabsen, Niels Klausen Ottosen
Life of this patent
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Abstract
A dispersion having an aqueous phase is filtered by a purality of membranes connected to pass the retentate or a portion of the retentate from one membrane step is used for feeding the one or more succeeding steps, and the permeate resulting from the plurality of membranes is subjected to a concentration step to produce a concentrate containing an increase concentration of dry matter, which is returned as a portion of the feeding dispersion to one or more of the plurality of membranes. The system provided with the membranes and concentration units and recirculation conduits is also disclosed.
Claims25
A process for the regulation of solids components in a dispersion having an aqueous continuous phase, comprising:
- feeding said dispersion to a primary filtration membrane in a first primary filtration membrane step;
- separating said dispersion into a retentate retained by said primary filtration membrane and a permeate passing through said primary filtration membrane;
- feeding the retentate or a portion thereof as the feeding dispersion into one or more succeeding primary filtration membrane steps;
- subjecting the permeate or a portion thereof from one or more of the primary filtration membrane steps to a concentration means to form a concentrated fraction containing an increased concentration of dry matter present in the permeate;
- and
- returning the concentrated fraction to the feeding dispersion of one or more of said primary filtration membrane steps;
- wherein said concentration means is selected from the group consisting of a secondary membrane filtration step, an evaporation step and a combination of such steps;
- and
- wherein said secondary membrane filtration step is carried out using one or more secondary filtration membranes having a smaller pore size than the pore size of said primary filtration membrane.
A system for regulating solids components of a dispersion having an aqueous continuous phase, comprising:
- a plurality of primary membrane filtration units, wherein each unit is connected to a feeding pipe, a retentate exit pipe, and a permeate exit pipe
- wherein said retentate exit pipe of at least one of said units is coupled to the feeding pipe of a succeeding unit;
- wherein the permeate exit pipes of said units are individually or collectively coupled to a plurality of concentrating units that separate the permeate into a diluted fraction and a concentrate;
- wherein each concentrating unit is coupled to an exit pipe for the diluted fraction and a concentrate exit pipe for the concentrate, each concentrate exit pipe being respectively coupled to a return pipe opening on to one or more of the feeding pipes of said plurality of primary membrane filtration units, wherein said return pipe does not open to the feeding pipe of a first primary membrane filtration unit;
- wherein said concentration units are selected from the group consisting of secondary membrane filtration units, evaporation units and combinations thereof;
- and
- wherein the membrane of said secondary membrane filtration units has a smaller pore size than the membrane of said primary filtration units.
A system as claimed in 19, wherein the primary membrane filtration units are ultrafiltration units, and each concentrating unit comprising a nanofiltration unit with a retentate exit pipe for the retentate and a permeate exit pipe for the permeate, wherein the permeate exit pipe is coupled to a RO-unit provided with a permeate exit pipe and a retentate exit pipe, and wherein the retentate exit pipe of the RO-unit is coupled to the return pipe.
A system for membrane filtration of a dispersion having an aqueous continuous phase, said system comprising a plurality of primary filtration units, wherein each primary filtration unit is connected to a feeding pipe, a retentate exit pipe, and a permeate exit pipe,
- wherein the retentate exit pipe of at least one of said primary filtration units is connected to or is an inlet to the feeding pipe of one or more succeeding primary filtration units,
- wherein the permeate exit pipes of said primary filtration units are individually or collectively coupled to a plurality of concentrating units coupled in series, wherein each concentrating unit is provided with an exit pipe for a diluted fraction and a concentrate exit pipe for a concentrate, and
- wherein each of said concentrate exit pipes are coupled to a common return pipe opening to one or more of the feeding pipes of said primary filtration units.
Dependencies are inferred from the claim text.