DE2548441A1 - Froth destruction system for fermenters - extracting froth into second vessel containing chemical destruction agents or froth centrifuge - Google Patents

Abstract

Froth produced in an aerated fermenter during the cultivation of microorganisms is destroyed by extracting it together with the used air from the fermenter. It is introduced through a frit at the bottom of a second vessel where chemical agents and/or mechanical impact discs destroy the froth. The system avoids the addn. of froth centrifuges at the head of fermenters which obstructs the access for probes and electrodes. The centrifuges are also expensive structures. Froth can now be eliminated readily or converted into re-usable fermenter fluid.

Description

Process and device for combating foam.

The invention relates to a method and a device for performing it of the method of combating foam in a ventilated fermenter vessel, in which creates foam during the cultivation of microorganisms and the disruptive foam is destroyed with chemical and / or mechanical aids.

In known processes, the foam in the fermenter vessels is through Addition of antifoam agents (chemical foam control) or by mechanical means Foam destroyer directly destroyed in the fermenter vessel (H.-J. Rehm, "Introduction to the Industrial Microbiology ", Springer-Verlag, Berlin, Heidelberg, New York, 1971).

However, these types of foam destruction have the disadvantage that they take place inside the fermenter vessel. This leads in chemical foam control to the fact that the added antifoam agent by the microorganisms themselves, ever after microorganisms and antifoams, of course, can be inactivated and / or hinder the work-up of the fermentation product, since they come back after use are difficult to separate from the fermenter liquid.

In the case of mechanical foam control in the fermenter vessel with e.g.

known foam centrifuges is the useful volume of the fermenter vessel reduced due to the space required by the centrifuge.

The required attachment to the fermenter head part, the foam rises to the surface of the fermenter liquid, hinders the introduction of probes and electrodes in the fermenter vessel, e.g. used for level measurement will. The subsequent installation of the foam centrifuges in fermenter systems is / very expensive. However, every fermenter vessel requires a foam destruction device.

The object of the invention is now to provide a method and to provide a means for performing this process with which the foam led out of the fermenter vessel without additional technical effort and in removed from independent plants or converted back into recyclable fermenter liquid will.

The solution to this problem is, according to the invention, that the exhaust air out of the fermenter housing the foam from the fermenter housing with that the exhaust air and the foam is blown into a second vessel, and that in this The chemical agent and / or the mechanical striking mechanism destroy the foam.

A continuation of this method is characterized in that the foam is introduced into the second vessel via a tube and a frit, that the exhaust air separated from the foam via a sterile exhaust air filter from the second The vessel and the liquid recovered from the foam are pumped into a secondary vessel will.

The device according to the invention for performing these above The process is characterized by a fermenter vessel with an exhaust pipe that goes up reaches to or via a tube in the second vessel, through in the second vessel arranged chemical and / or mechanical means, through the second vessel, the one Drainage pipe and an antifoam probe, and either through an overflow vessel, which has an exhaust air sterile filter and is connected downstream of the second vessel, or through a return line from the second vessel to the fermenter vessel, embodiments this device can be characterized in that in the overflow line a hose pump is arranged to the overflow vessel that one of the antifoam probe generated signal via an electrical circuit actuates the hose pump and that the mechanical means is a foam centrifuge.

The advantages of this method or the devices according to the invention to carry out these methods consist in chemical foam control does not hinder the processing of the fermenter content that the fermentation product is not chemically contaminated, and that it becomes exhaust air with small amounts of exhaust air analysis can be used without an electronic dosing device.

The advantages of mechanical foam control are: that despite the use of known foam centrifuges, the useful volume of the fermenter vessel is not degraded, a foam destroyer connected to several at the same time Fermenter vessels used can be, the connection of the mechanical Foam destroyer to existing devices without installation in them is possible, the construction of the fermenter boiler head part can be made simpler and the introduction of probes and electrodes e.g.

is made considerably easier with small fermenters. In addition, the Foam destroyer can be replaced while the fermenter is in operation.

The invention is illustrated below with the aid of two exemplary embodiments explained in more detail by means of FIGS. 1 to 3.

Figure 1 shows a schematic representation of the device for performing of the method according to the invention, FIG. 2 shows a section through a second vessel with chemical foam destruction and FIG. 3 a section through a second vessel with mechanical destruction of the foam.

In the figure 1, a fermenter vessel 1 is shown in which the fermenter liquid 2 is included. It is swirled by an agitator 3 via a magnetic motor 4. Via a filter 5 in a supply air line 6, the fermenter liquid is gas or Air supplied. The foam 7 produced by the ventilation and mixing becomes together with the exhaust air through a simple mechanical one connected to an agitator shaft Foam destroyer 8 at the head end of the fermenter vessel 1 through the discharge line discharged into the second vessel. Here, the exhaust air tears the foam when this the Reached the height of the gap 8, simply with.

The exhaust line 9 opens into the second vessel lo near the Bottom 11. The foam or the foam occurs via a schematically illustrated frit 12 Exhaust air from fermenter vessel 1 or the supply air to the second vessel lo into the solution 13 with known antifoam agents (e.g. silicone oil Bayer E or polypropylene glycol P 2000 from Fluka AG, Buchs, Switzerland). The exhaust air escapes at the head of the second Vessel lo via a further exhaust air line 14 and a sterile filter 15.

Through a side chimney (see also Figure 2) 16 is a Antifoam probe 17 inserted into the interior of the second vessel 10. she will Connected to a control unit 19, 20 via an electrical line 18. Increases the liquid 13 in the second vessel 10 and touches the antifoam probe 17, so the electrical circuit 19, 20 is closed and one not shown in detail Relay actuates a hose pump 21, which the liquid 13 via a drain 22 pumps out of the second vessel 10. The pump 21 pumps the excess liquid 13 in a secondary or collecting vessel 23. This secondary vessel # 23 has a known Way a central screw cap (shown schematically) illit sliding connection, through which the insert 24 made of glass is inserted. The insert 24 has one Inlet connection 25 with hose olive for the supply line 22. An outlet connection 27 has a sterilizable cotton seal 28, which acts as a vent when influx of Liquid is used.

The second vessel 10 is shown again in FIG. The second Vessel 10 with the solution or fermenter liquid 13 has a centrally arranged one Screw cap 29 and the side-mounted chimney 16 with screw cap 30th

Both screw caps 29 and 30 have sliding connections. By an insert 31 made of glass is inserted into the middle sliding connection. This insert 31 takes the supply air line 9 with the frit 12 at the bottom of the second Vessel, the overflow line 22, the exhaust air line 14 to the sterile filter 15 and a upper opening 32 with screw thread and screw cap for adding the antifoam agent on. Furthermore, a glass extension 33 is attached to the insert 31, through which a Platinum wire 34 is immersed in the liquid 13 via the discharge line 22.

About the side chimney 16 and the screw connection 30 is the antifoam probe 17 is introduced into the second vessel 10.

One pole of the plug-in coupling 35 on the antifoam probe 17 is connected to the Contact 36 connected to platinum wire 34.

A vessel 37 corresponding to the second vessel 10 is shown in FIG. in which a foam centrifuge 38 of known type is driven by a motor 39 will. The feed and discharge line 9 from the fermenter vessel is on this second vessel 37 1 connected laterally according to Figure 1. The exhaust air line 14 (for itself corresponding Parts have been given the same reference numerals as in Figures 1 and 2) is at the top End next to the foam centrifuge 38 arranged. In contrast to the execution after Figure 1 and 2 is here the drain or overflow line 22 on the conical Bottom 40 of the second vessel 37 is arranged. The pump 21 can transfer the liquid 13 in this case pump back directly to fermenter 1.

Pumping the liquid out of the second vessel lo or

37 can, especially in the case of the first exemplary embodiment, high foam feed from fermenter 1 result. The hose connections 9, 22 to the second Vessel LO or 37 and from this to the exhaust air sterile filter 15 are isolated to one To counteract the formation of condensation. For the same reason, the second vessel 10 or 37 itself be isolated.

Claims (6)

Claims: 1. A method for combating foam in one ventilated fermenter vessel in which foam is created during the cultivation of microorganisms and the disruptive foam is destroyed with chemical and / or mechanical aids is, characterized in that the exhaust air from the fermenter housing (1) the foam out of the fermenter housing (1) with that the exhaust air and the foam in one second vessel (10, 37) is blown and that in this vessel (10, 37) the chemical Means and / or the mechanical hammer mechanism (38) destroy the foam. 2. The method according to claim 1, characterized in that the foam Introduced into the second vessel (10, 37) via a feed line (9) and / or a frit (12) that the exhaust air separated from the foam is passed through an exhaust air sterile filter (15) the second vessel (10, 37) and the liquid returned from the foam Secondary vessel (23) or to the fermenter (1} is pumped out. 3. Device for Duwchfuhren the method according to claim 1 and 2, characterized by gin fermenter vessel (1) with exhaust air line (9) that extends up to or / a tube extends into the second vessel (10, 37), through in the second vessel (10, 37) arranged chemical and / or mechanical means (38), by a discharge line (22) and an antifoam probe (17) in the second vessel (10) and either through an overflow vessel (23) which has an exhaust air sterile filter (28) and the second The vessel (10) is connected downstream, or a return line (22) from the second vessel (37) to the fermenter vessel. 4. Device according to claim 3, characterized in that in the Overflow line (22) to the overflow, secondary or collecting vessel (23) a hose pump (21) is arranged. 5. Device according to claim 3 or 4, characterized in that a signal generated by the antifoam probe (17) via an electrical circuit (19, 20) actuates the peristaltic pump (21). 6. Device according to claim 3, characterized in that the mechanical Means a foam centrifuge. (38) is.