Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
  • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
  • B01F27/86—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis co-operating with deflectors or baffles fixed to the receptacle
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
  • C12M27/00—Means for mixing, agitating or circulating fluids in the vessel
  • C12M27/02—Stirrer or mobile mixing elements
  • C12M27/08—Stirrer or mobile mixing elements with different stirrer shapes in one shaft or axis
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
  • C12M27/00—Means for mixing, agitating or circulating fluids in the vessel
  • C12M27/18—Flow directing inserts
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
  • C12M41/00—Means for regulation, monitoring, measurement or control, e.g. flow regulation
  • C12M41/12—Means for regulation, monitoring, measurement or control, e.g. flow regulation of temperature
  • C12M41/18—Heat exchange systems, e.g. heat jackets or outer envelopes
  • C12M41/22—Heat exchange systems, e.g. heat jackets or outer envelopes in contact with the bioreactor walls

Definitions

• the transport routes are determined by the distribution of the catalytically active substances, in fermentations by the distribution of the cells.
• Fermentation reactions cause such a dead zone formation to change the desired metabolic reactions, in the worst case an irreparable damage to the affected cells and their death.
• an irreparable damage to the affected cells and their death In the course of a batch-wise antibiotic fermentation of up to 300 h, almost all cells occasionally stay in such zones, even if they only occupy 2-3% of the reactor volume.
• the stirring elements have the task of mixing the reaction system, breaking up and distributing the injected gas, the heat of reaction via the reactor jacket and / or Dissipate cooling internals and, under certain circumstances, prevent agglomerate formation beyond a certain size by introducing shear forces.
• agitators have so far been of the quality of the ones they cause
• Mass transfer from the gas to the aqueous phase has been optimized, less according to the quality of their mixing effect.
• the stirrer performance was increased and the reactor volumes were increased; reactors, which were considered to be homogeneously mixed, developed apparatuses divided into zones with ventilation, degassing and heat exchange zones.
• the currently customary nutrient solutions show non-Newtonian pseudoplastic behavior.
• the stirrers used usually have three to five levels and a stirrer / tank diameter ratio of 0.35 to 0.65.
• baffles are mounted on the edge of the container at a short distance from the wall, the width of which perpendicular to the flow of the stirrer is approximately 8 to 10% of the container diameter. Behind them, stationary vortexes or even dead zones form with the disadvantages described above, especially in the case of structurally viscous reaction mixtures.
• the object of the present invention is now to avoid the disadvantages of the prior art and, in particular, to effect such a flow control that the above-described dead zones cannot occur, the mixing action of the stirring element and the heat transfer are improved, and the low-mixing rotary movement of that in the reactor Reaction mixture can be prevented.
• the present invention therefore relates to a method for improving the mixing quality of liquid, in particular viscous, media in stirred tank reactors, characterized in that that the medium set in motion by stirring elements undergoes a change in direction at one point or more points on the inner wall of the reactor at different heights in the direction perpendicular to the flow of the stirrer.
• the present invention relates to a stirred tank reactor which is provided with the usual stirring elements and with flow-influencing elements (baffles) and, if appropriate, further internals, jacket cooling elements and devices for ventilation, with the characteristic that the baffle at one or more points of the Deflection elements are attached at different heights of the reactor, which cause a change in direction in the direction perpendicular to the flow of the stirrer.
• baffles flow-influencing elements
• liquid systems such as fumigated suspensions, emulsions and / or dispersions, are suitable for the process according to the invention. This is particularly suitable for fumigated fermentation broths.
• liquid systems for the purposes of the invention are: tylose solutions, starch solutions, polymerization mixtures, fermentation broths for the production of antibiotics such as penicillin or tetracycline, cephalosporin, streptomycin, xanthan fermentations and the like.
• the deflection of the liquid streams moved radially and tangentially onto the reactor wall by the stirring device takes place according to the invention perpendicular to the inflow direction, ie in the direction of the longitudinal axis of the reactor or the axis of the stirring device. Usually this only happens in one direction, i.e. upwards or downwards. Under certain circumstances, however, it can be useful to alternately deflect upwards and downwards.
• the size of the deflection is of course dependent on the angle of attack of the individual elements of the baffle (s) according to the invention; the viscosity of the liquid medium and the stirring energy also play a role.
• the change in direction according to the invention produces a defined preferred direction of the mixture movement near the wall of the reactor and at the same time increases the speed of the flowing medium.
• the stirred tank reactor according to the invention can in principle have any shape; in general, however, it is designed as a standing cylinder.
• the baffle (s) contained therein consists (in each case) of a number of thin sheet-like bodies which are preferably arranged vertically one above the other in the longitudinal axis of the reactor, preferably plates which face the direction of flow, ie to a plane perpendicular to the longitudinal axis of the reactor ( Stirrer) are inclined.
• This angle of inclination is generally the smaller, the less viscous the medium and the higher the flow velocity, and is expediently ⁇ 20 to ⁇ 85 °, preferably ⁇ 30 to ⁇ 60 °. as a rule, this angle is the same for all elements of a baffle.
• the angles of attack may differ from baffle to baffle, in particular alternating. In the latter case, there is an alternating deflection in one direction (upward) and the opposite direction (downward).
• the plate-shaped body of the baffle according to the invention mostly represent rectangles or squares; they can be flat or curved. In special cases, these plate-shaped bodies can also represent close-meshed grids, provided they can withstand the inflow pressure.
• the baffles of a baffle arranged one above the other can be attached directly to the inner wall of the container. However, they are preferably attached to a corresponding holder running in the longitudinal direction of the reactor, such as single or double stands, especially so that the angle of attack can be variably adjusted.
• the distance between these deflecting elements is advantageously 3 to 30%, preferably 10 to 15% of the container diameter.
• the number of individual elements of a baffle depends on the container height.
• baffles according to the invention is advantageously between 1 and 8; preferably 4 baffles are used.
• the baffles ie the holder and the individual deflection elements
• the baffles can be hollow for receiving a coolant or heating means.
• basically all devices known for this purpose can serve as stirring elements, which result in a suitable flow characteristic and a sufficient stirring capacity, for example impeller stirrers, turbine stirrers, inclined-blade turbines, blade stirrers, Inter-MIG stirrers, MIG stirrers, Frings stirrers and the like.
• Such stirring elements suitable for the purposes of the invention are described, for example, in the article by Kipke "Stirring low-viscosity and medium-viscosity media", CIT 51 (1979), pp.
• stirred tank reactor contains the usual internals, such as filler neck, valves, pumps, pipelines, regulating, control and measuring instruments and, if appropriate, attachments, such as reflux coolers.
• stirred tank reactor If the stirred tank reactor according to the invention is used for fermentations, the usual devices for gassing the reaction medium are also provided on it, i.e. corresponding inlet and outlet pipes and usually an annular nozzle connected to the inlet pipe; alternatively there are also one
• Figure 1 shows the reactor in longitudinal section along the line II of Figure 2, while Figure 2 shows a cross section along the line II-II of Figure 1.
• (1) means the reactor designed as a standing cylinder, (2) the multi-stage impeller with the blades (3).
• the reaction gas is introduced into the reactor through the inlet pipe (4) through the nozzle ring (5) and sucked in together with the fluid reaction suspension through the stirrer and moved radially and tangentially in the direction of the reactor wall, where the baffle according to the invention, consisting of the individual elements ( 6) and the bracket (7) designed as a double rod is deflected downwards according to the streamlines (8).
• This creates a defined preferred direction of the mixture movement and at the same time results in a higher speed of the mixture in the wall area, which also results in an improvement in the heat transfer to the cooling jacket (9).
• a 1.30 l stirred kettle which contained four of the baffles according to the invention, each with 8 rectangular baffles, each with a size of 0.0032 m 2 , and which was equipped with a two-level disk stirrer (number of blades: 6), a 1 , 3% tylose solution mixed and the mixing time determined by color change measurements.
• the angle of attack of the deflection elements when using the baffle according to the invention was 45 °.
• the baffles were held by a double rod attached to the reactor floor and head; they extended over 10% of the container diameter in the radial direction and their distance from the reactor wall was 0.01 D.
• Example 1 was repeated, but using a blade stirrer instead of the two-tier disc stirrer.
• the power consumption (stirring energy) was 1 kW / m 3 and the mixing time was 18 s.
• Example 3 A 40 m 3 fermentation kettle which contained four of the baffles according to the invention was used to produce penicillin; the number of rectangular deflection plates per baffle was 18, the angle of attack was 40 °, the size of the baffles was 0.075 m 2 ; they covered 9% of the
• the suspension was adjusted to a pH of 6.0 with sodium hydroxide solution and sterilized with steam at 120 ° for 40 min. After cooling the nutrient solution on
• the fermentation kettle was inoculated at 25 ° C. with 3000 l of well-washed penicillin preculture.
• the fermentation was carried out at 25 ° C. with aeration with 0.51 air / 1 filling volume and a stirring energy of 2.5-3 kW / m 2 .
• soybean oil was added several times in portions of approximately 5 l during the fermentation, the total amount being 5-1000 l.
• the fermentation time was 150 hours and the yield 14,950 U / ml.
• Example 3 was repeated, but in a fermentation vessel which, instead of the four baffles according to the invention, contained conventional baffles with a width of 0.1 D.
• the nutrient solution was sterilized with direct steam at 120 ° for 30 min, cooled and inoculated with 1500 l of well-grown tetracycline preculture when 28 ° was reached.
• the fermentation is carried out at 28 ° for up to 12 hours and then at 25 ° C;
• the aeration was carried out with 0.5 l of air / 1 filling volume and the stirring energy was 2 kW / m 3.
• a solution of 750 kg of sugar and 180 kg of ammonium sulfate in 2000 l of drinking water, which was at 120 ° 30 min. had been sterilized.
• a second dispensing took place after about 72 hours; it consisted of a solution of 750 kg of sugar in 2000 l of drinking water, which had been sterilized as stated above.
• Foaming agents were also used during the fermentation
• Example 4 was repeated, but in a fermentation kettle with 4 conventional baffles with a width of 0.1 D. The yield here was 8300 U / ml.

Landscapes

• Chemical & Material Sciences (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Zoology (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Microbiology (AREA)
• General Engineering & Computer Science (AREA)
• Genetics & Genomics (AREA)
• Sustainable Development (AREA)
• Biomedical Technology (AREA)
• General Health & Medical Sciences (AREA)
• Biochemistry (AREA)
• Biotechnology (AREA)
• Analytical Chemistry (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Apparatus Associated With Microorganisms And Enzymes (AREA)
• Mixers Of The Rotary Stirring Type (AREA)
• Micro-Organisms Or Cultivation Processes Thereof (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6080406

Family Applications (1)

Country Status (6)

Families Citing this family (11)

Citations (10)

Family Cites Families (15)

• 1979
  • 1979-09-08 DE DE19792936388 patent/DE2936388A1/de not_active Withdrawn
• 1980
  • 1980-09-05 JP JP50206380A patent/JPS56501549A/ja active Pending
  • 1980-09-05 US US06/261,195 patent/US4378436A/en not_active Expired - Fee Related
  • 1980-09-05 AT AT80105314T patent/ATE7308T1/de not_active IP Right Cessation
  • 1980-09-05 WO PCT/EP1980/000093 patent/WO1981000722A1/de not_active Ceased
  • 1980-09-05 EP EP80105314A patent/EP0025571B1/de not_active Expired
  • 1980-09-05 DE DE8080105314T patent/DE3067696D1/de not_active Expired

Patent Citations (10)

Also Published As

Similar Documents

Legal Events