Patent Application
20210187456
Mixing vessels are mounted to mixer bases for use. However, different mixing vessels have different shapes and/or configurations and can require specialized mixer bases for use.
The present invention provides for ameliorating at least some of the disadvantages of the prior art. These and other advantages of the present invention will be apparent from the description as set forth below.
An embodiment of the invention provides a mixer base assembly comprising (a) a body having (i) an upper end including a mating face for mixing vessel connection; (ii) a lower end including a cavity; (iii) a plurality of side walls; (iv) an inlet port arranged in a side wall; (v) an outlet port arranged in a side wall; (vi) a sampling port arranged in a side wall; (vii) at least one probe port arranged in a side wall; and, (viii) a fluid mixing chamber including a baffle, the fluid mixing chamber having a bottom wall; (b) an impeller seat arranged in the cavity in the lower end of the body; and, (c) a levitating magnetic impeller arranged in the impeller seat, the impeller comprising a magnet, a base, and at least two blades, wherein the at least two blades extend above the bottom wall of the fluid mixing chamber into the fluid mixing chamber.
In another embodiment, a method for mixing fluid comprises connecting a mixing vessel to a mixer base assembly comprising (a) a body having (i) an upper end including a mating face for mixing vessel connection; (ii) a lower end including a cavity; (iii) a plurality of side walls; (iv) an inlet port arranged in a side wall; (v) an outlet port arranged in a side wall; (vi) a sampling port arranged in a side wall; (vii) at least one probe port arranged in a side wall; and, (viii) a fluid mixing chamber including a baffle, the fluid mixing chamber having a bottom wall; (b) an impeller seat arranged in the cavity in the lower end of the body; and, (c) a levitating magnetic impeller arranged in the impeller seat, the impeller comprising a magnet, a base, and at least two blades, wherein the at least two blades extend above the bottom wall of the fluid mixing chamber into the fluid mixing chamber; introducing fluid into the fluid mixing chamber, and rotating the magnetic impeller to mix the fluid in the fluid mixing chamber.
In accordance with an embodiment of the invention, a mixer base assembly is provided comprising (a) a body having (i) an upper end including a mating face for mixing vessel connection; (ii) a lower end including a cavity; (iii) a plurality of side walls; (iv) an inlet port arranged in a side wall; (v) an outlet port arranged in a side wall; (vi) a sampling port arranged in a side wall; (vii) at least one probe port arranged in a side wall; and, (viii) a fluid mixing chamber including a baffle, the fluid mixing chamber having a bottom wall; (b) an impeller seat arranged in the cavity in the lower end of the body; and, (c) a levitating magnetic impeller arranged in the impeller seat, the impeller comprising a magnet, a base, and at least two blades, wherein the at least two blades extend above the bottom wall of the fluid mixing chamber into the fluid mixing chamber.
In some embodiments, the impeller seat is fluid tightly sealed to the bottom wall of the fluid mixing chamber. Alternatively, it can be included as part of the fluid mixing chamber (e.g., as a single, injection-molded part).
In a typical embodiment, the mixer base assembly includes two probe ports.
In some embodiments, the mixer base assembly further a vent inlet port and a vent outlet port, wherein the vent outlet port is arranged in a side wall of the body. In another embodiment, the vent outlet port is arranged in the body of the mixing vessel.
In a preferred embodiment, the bottom wall of the mixing chamber slopes downwardly toward the outlet port, and in a more preferred embodiment, the mixer base assembly further comprises at least one probe arranged in the at least one probe port, wherein a tip of the at least one probe (where the sensing element is located) is angled downwardly into the mixing chamber. In some embodiments, the mixer base assembly includes two probe ports, and two probes, each arranged in a separate probe port, wherein the tip of each probe is angled downwardly into the mixing chamber.
In another embodiment, a method for using a mixing fluid comprises connecting a mixing vessel to a mixer base assembly comprising (a) a body having (i) an upper end including a mating face for mixing vessel connection; (ii) a lower end including a cavity; (iii) a plurality of side walls; (iv) an inlet port arranged in a side wall; (v) an outlet port arranged in a side wall; (vi) a sampling port arranged in a side wall; (vii) at least one probe port arranged in a side wall; and, (viii) a fluid mixing chamber including a baffle, the fluid mixing chamber having a bottom wall; (b) an impeller seat arranged in the cavity in the lower end of the body; and, (c) a levitating magnetic impeller arranged in the impeller seat, the impeller comprising a magnet, a base, and at least two blades, wherein the at least two blades extend above the bottom wall of the fluid mixing chamber into the fluid mixing chamber; introducing fluid into the fluid mixing chamber, and rotating the magnetic impeller to mix the fluid in the fluid mixing chamber.
Embodiments of the method can further comprise, for example, measuring or detecting a parameter of the fluid in the fluid mixing chamber (e.g., measuring the pH and/or the conductivity of the fluid) and/or sampling the fluid in the fluid mixing chamber and/or venting air from the mixer base assembly.
Advantageously, embodiments of the present invention provide a “clever base” that can be used with a variety of mixing vessels having different shapes and/or configurations. Homogenized mixing of a wide range of liquid volumes (e.g, about 35 ml to about 10,000 ml) and/or a liquids having wide range of viscosities (e.g., about 1 to about 25 Centipoise (cP)) can be achieved while minimizing or eliminating splashing, foaming, and/or vortexing of the liquids. Moreover, the use of a levitating magnetic impeller significantly reduces shear force, and eliminates rubbing of parts, thus reducing or eliminating particle shed that could contaminate the fluid.
Embodiments of the invention can be used with low volume mixing vessels, and if desired, can be connected to aseptic sampling devices (manual or automatic). If the mixing vessel does not have a vent filter, embodiments of the invention can include connection for a vent filter to maintain sterility and equilibrium of pressures within the system.
Preferably, the mixer base assembly is single-use.
Each of the components of the invention will now be described in more detail below, wherein like components have like reference numbers.
The illustrated embodiment of the mixer base assembly 500 comprises a body 550 having an upper end 571 including a mating face 575 for mixing vessel/mixing vessel adapter connection; a lower end 572 including a cavity 557; a plurality of side walls (4 side walls 551A, 551B, 551C, 551D are illustrated; an inlet port 501 (shown in more detail in
As shown in
In the illustrated embodiment shown in
Optionally, as shown in
If desired, embodiments of the mixing base system 1000 or the mixer base assembly can include a sampling arrangement 700 comprising a sample port plug 707 and sample port nut 707A, wherein the sample port plug 707 can be arranged in the sampling port 507. In some embodiments, the sampling arrangement is for use with a threaded connection such as, for example, a DN 25 threaded connection. If desired, an autosampling system can be installed through the sampling port 507 and/or manual sampling can be carried out through outlet port exit 502″. Illustratively, samples can be taken offline to measure parameters that the probes are not reading or to confirm a probe reading or to calibrate a sensor.
Additionally, or alternatively, embodiments of the mixing base system 1000 or the mixer base assembly can include a connector system 900 comprising an inlet connector 201 and an outlet connector 202, such as aseptic connectors. A variety of connectors, including aseptic connectors, are commercially available, from, for example, Pall Corporation (Port Washington, N.Y., e.g., KLEENPAK® PRESTO); Cole-Parmer (Vernon Hills, Ill.); and Eldon James (Denver, Colo.).
Embodiments of the mixing base system or the mixer base assembly further comprise at least one probe 800, typically, two probes 818, 819 (in some embodiments probe adapters 818B and 819B are used to connect the probes to the probe ports), wherein
A variety of probes are suitable for use in embodiments of the invention, and are commercially available. Suitable probes include, for example, pH probes, conductivity probes, temperature sensors, dissolved oxygen probes, and cell counters.
The body can be fabricated from any suitable rigid impervious material, including any impervious thermoplastic material, which is compatible with the fluid being processed. For example, the housing can be fabricated from a metal, such as stainless steel, or from a polymer. In a preferred embodiment, the body is injection molded. The adapter plate is preferably plastic, and cannot be a magnetic material.
The mixer base assembly is connectable to a variety of mixing vessels (e.g., as shown in
Mixing vessels can be docked to a variety of drive systems. Drive systems include a motor, an input/output (TO) module, a power supply, fans, wiring and connectors, and, optionally, a weighing system, arranged in a housing.
The illustrated housing 2300 includes a front cover 2301, a rear cover 2302, a top cover/mixer base support 2303, and a chassis 2304.
A variety of motors for magnetically levitating and spinning the impellers are known in the art. Commercially available motors include those available from Pall Corporation (Port Washington, N.Y.; e.g., LEVMIXER® SYSTEM) and Levitronix GmbH (Zurich, Switzerland).
The mating face of the mixer base assembly can be adapted for connection to a variety of size, shape, and/or type of mixing vessels, and the bottom surface of the interface plate can be adapted for docking to a variety of drive systems. In some embodiments, components and/or processes such as screws, pins, bolts, mounting rings, adapters, o-rings (with or without grooves or channels in the mating face), sanitary gaskets, and/or ultrasonic welding can be used for efficient connection.
The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.
This example demonstrates the quick (less than 60 seconds) homogenous mixing time and low carry-over volume (less than 20 mL) when using a mixer base assembly according to an embodiment of the invention with a variety of mixing vessels and fluid viscosities.
An embodiment of a mixer base assembly as generally shown in
In each experiment, the fluid volume is 100 mL, and the impeller speed is 700 rpm. In one set of experiments, the fluid viscosity is 1 cP, in the other set of experiments, the fluid viscosity if 25 cP.
The homogenous mixing time is conducted via additions of acids and bases, and time recorded to stability of pH, defined as a 10 second period of time with a pH change of <0.1. At 1 cP, the mixing time for the acid is 14 seconds, and the mixing time for the base is 13 seconds. At 25 cP, the mixing time for the acid is 24 seconds, and the mixing time for the base is 31 seconds.
The carry-over volume for the mixing vessel shown in
This example demonstrates the quick (less than 60 seconds) homogenous mixing time and low carry-over volume (less than 20 mL) when using a mixer base assembly according to an embodiment of the invention with a variety of mixing vessels and fluid viscosities.
This example is similar to Example 1, with the exception that the fluid volume is 10,000 mL (100:1 turndown ratio), and the impeller speed is 5000 rpm.
As with Example 1, in one set of experiments, the fluid viscosity is 1 cP, in the other set of experiments, the fluid viscosity if 25 cP.
At 1 cP, the mixing time for the acid for the mixing vessel shown in
At 25 cP, the mixing time for the acid for the mixing vessel shown in
As with Example 1, the carry-over volume for the mixing vessel shown in
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms “a” and “an” and “the” and “at least one” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
