DD160356A3 - PROCESS FOR THE FERMENTATION AND SEPARATION OF MICROORGANISMS - Google Patents

Abstract

The invention relates to a process for the fermentation and separation of microorganisms, in particular for the production of unicellular protein. The aim of the invention is the reduction of the fermentation agent requirement for the separation process. At the same time, the occurrence of a stable water / biomass - in oil emulsion above 60 degrees C should be excluded. The fermentation and separation is carried out using a polymerization product of ethylene oxide and propylene oxide, wherein the separation takes place at temperatures of 60 to 90 degrees C. According to the invention, the polymerization product has an average molecular weight of 2300-4100 and a concentration of up to 0.06 wt .-%. The separation is carried out in the presence of at least 600 mg / l potassium ions.

Description

Title of the invention

Process for the fermentation and separation of microorganisms

Field of application of the invention

The invention relates to a process for the fermentation and separation of microorganisms. It can be used in industrial plants for growing microorganisms for the purpose of obtaining binseller protein.

Characteristic of the known technical solutions

The prior art is best determined by the following four solutions:

1. According to DD patent 104099 were microorganisms

- Yeasts grown in the presence of a fermentation aid and a separation aid at 30-34 C and separated from the culture mixture at also 32 35 ⁰ G.

The known polymerization of ethylene oxide and propylene oxide is used as Ferinentationshilfsmittel having an average molecular weight of 1750 - 2250. As a separation aid and simultaneous partial resource of Fermentationsprosesses an alkyl sulfonate is used having an average chain length of C ^ p - ^ 20 * ^ ⁿ ^ ^s S ^enanj 2nd molecule ar In the case of both surfactants, the highest performance increases of the fermentation process were achieved.

2. According to DE patent specification 1417 559, a process is known in which microorganisms without fermentation

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cultured, but then be separated with the addition of Separationahilfsittein. The separation can be carried out according to this method at 32 ⁰ C.

To reduce the Separationshilfsmittelbedarfes is proposed in this patent, the maximum temperature to 99 ⁰ C, but preferably _only T ₀ - ^ ₃ ^ q ° q _s and the pH on the same side increase to 8 au.

According to DE 2,544,625, a process for the separation of microorganisms has been developed in which the microorganisms are grown in the presence of 0.1-0.6 % of the known auxiliary fermentation aid of ethylene oxide and propylene oxide having an average molecular weight of 1750-2250.

The separation of the Ilikroorganismen is achieved by the separation at 60-85 C after increasing the fermentation aid before separation to 0.07 0.13 % .

iTach Schonfeld ("Surface-Active Addition Products of Ethylene Oxide" - V / sseenliche Verlagsgesellschaft MBH Stuttgart 1959 p. 94/95) is in the sole presence of EO / PO adducts, for example those mentioned under (1) and (3) Fermentation aid, a separation of the microorganisms by separation at a temperature below the cloud point of the adduct, for example below 60 C, conceivable since the dehydration of the surfactant molecules and thus the qualitative turn into the oil solubility as a prerequisite for the separation process by adding Ha, K , Li-ion can be induced.

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This prior art has the following disadvantages

 The process according to (1) requires two auxiliaries. In addition, the highly surfactant Separationshilfsraittel is adsorbed on the microorganism surfaces. The surfactant thus present after separation in the biomass is also highly hygroscopic and affects the processing, storage and application behavior of the biomass

 These principal disadvantages also apply to the method according to (2).

In this method, in the case of a desired improvement in the fermentation process, a fermentation aid must be used, which in turn leads to Einsat a two aids.

In the case of the method according to (3) these ITachteile are overcome.

Here only an increase in concentration of 0.06 to at least 0.07 ^c / o of fermentation aids and heating is necessary. However, the increase in concentration leads to a marked increase in the consumption of fermentation aids and thus to an increase in costs.

When using a conceivable according to (4) process, the need for auxiliaries is even higher than in (3), since the dehydration effect by 3Ja-, K-, Li-ion is significantly lower than in the case of the qualitative indexed by heat increase in the dissolution dissolution. However, if the increase in temperature is applied, the effect described by Schönfeld is ineffective and it applies to (3) said.

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The aim of the invention.

The aim of the invention is to reduce the fermentation aid requirement for the separation process. The object of the invention is to introduce a coupled fermentation separation process in which the auxiliary agent used for the fermentation process is not increased above the value of 0.06 % and in which the subsequent separation process does not require an increase in concentration. The usual rate of increase of the power of 1.5-1.7 reached in the fermentation process with the fermentation aid should at least be reached or outbid.

On the same side, the occurrence of stable Yasser / bioraasse-in-oil-emulsions above 60 C should be excluded.

Explanation of the essence of the invention

Surprisingly, it has been found that this object can be achieved if a polymerization product of ethylene oxide and piopylene oxide is used as the fermentation product, but with 2300-4,100 a higher average molecular weight than the range of 1750-2250 previously estimated as optimal has, and in the suspension to be separated at least 600 mg / 1 potassium ions are contained and the separation at 60 - 99 ⁰ C is performed.

It has been found that in the case of the use of said fermentation aid of ethylene oxide and propylene oxide having a molecular weight in the range of 2300 to 4100 of 0.03 to 0.06 % based on the fermentation medium, a performance increase of 1.5 to 1.9 is achieved in the fermentation process and that for the

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Separation at 60-85 ⁰ G Iceine further concentration increase is necessary, if in the suspension to be separated mindeatens 500 mg / 1 potassium ions were vornanaen · Hach the separation is also completely recycled the aqueous phase contained potassium and Fernientationshilfsmittel in the fermentation process.

In this way, the separation process is charged with no cost of aids, since the potassium is known to be required in the fermentation process as lahrkomponente.

embodiments

in a small-scale Sührkesselfermentor Lodderomyces elongisporus is grown continuously on n-alkane-containing petroleum distillate.

The following conditions and process parameters are set:

Filling quantity in the fermenter: 200 kg

amount of air supplied: 25 hormone cubic meters per

hour

Specific stirrer power: 1.5 watts per kilogram of petroleum distillate content in

Fermentation mixture: 20% by weight average "residence time

Fermentori 4 hours

The fermenter was further fed a nutrient solution containing nitrogen, potassium, phosphorus and other Wähx- and trace elements in sufficient quantity. Overall, the conditions were adjusted so that over all Yarsuchsstrecken oxygen remained the limiting factor for the productivity of the fermentation process.

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The overall test was divided into four sections of '4 days each.

During these 4 days successive perforations of EthylBnoxid / propylene oxide were used with the following average molecular weight:

1st section 2300

2nd section 2600

3. Section 4Ю0

4th section without fermentation aids

The concentration of fermentation aid was adjusted by means of fine dosing to 550 ± 50 mg / l fermentation rate and kept constant over a total of 12 days. In the last 4 days no Pernientationsliilfsraittel was introduced as a control experiment.

The following average values of the productivity of the fermentor were obtained:

1st section 4.4 kg yeast dry matter / kg fermenter

content. hour

2. Section 4.5 kg of yeast dry matter / kg fermenter

content ♦ hour

3. Section 4j 35 kilograms of yeast dry matter / kg fermenter

content. hour

4. Section 2.33 kg of yeast dry matter / kg fermenter

content. hour

The culture mixture leaving the perforator was subjected to a continuous decantation. An aqueous culture medium was obtained as the heavy phase, which was returned immediately to the fermenter. The light phase was obtained as a microorganism suspension containing on average 3 % of yeast dry matter and 3 % of petroleum distillate. This Sus-

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The board was heated with a heating coil and directed into a small-scale nozzle separator of known design for separation. During the evaluation, the content of ionic ions in this suspension was adjusted to 600 mg / l. Above 60 ⁰ G good oil separation was achieved in all three test sections. In the 4th section was dispensed with a separation. The heavy phase was largely oil-free and had on average the following composition:

Yeast dry matter 4.5 - 6 % petroleum distillate 0.5 - 0.8 % water balance

This suspension was continuously subjected to separation in a 2nd DÜ3enseparator to give a yeast concentrate of the following composition:

Yeast dry matter 19 - 21 $ Petroleum distillate 1,8 - 2,2 %

Water rest

As a light phase, the potassium and fermentation aid-containing aqueous culture liquid was separated. This culture liquid was used for nutrient solution preparation and thus continuously recycled to the fermentation process.

Claims (1)

21? 415 A process for the fermentation and separation of microorganisms using a Polyrnerisationsproduktes .from ethylene oxide and propylene oxide, in which the separation at temperatures of 60 - 90 ⁰ C is performed, characterized in that the polymerization; product ice medium molecular weight of 2300 4100 and a concentration to su 0.06 G-ev; .- ^ and that the separation in the presence of at least βΟΟ mg / 1 Zaliumionen is performed.