SU905280A1 - Process for producing biomass - Google Patents

Description

one

The invention relates to the microbiological industry, in particular to methods for producing biomass by cultivating microorganisms on hydrocarbon-containing media, followed by "separating biomass from a suspension.

A known method of biomass extraction involves the cultivation of microorganisms on hydrocarbons in the presence of surfactants with a subsequent j0 release of biomass with the addition of surface-active and organic substances til.

The method is characterized by an insufficient effect of biomass release and complexity.

the process of cultivating microorganisms.

The purpose of the invention is to simplify the process of cultivating microorganisms.

The goal is achieved by the fact that according to the method of producing biomass, which involves the aerobic cultivation of microorganisms on a nutrient medium containing liquid hydrocarbons as a carbon source, JS

source of nitrogen, necessary mineral sources of nutrition and surface-active substances, followed by you, by dividing the biomass by adding a mixture of surface-active and organic substances, cultivation of microorganisms

lead when adding a mixture used in the allocation of biomass, while as organic substances use polyethylene glycol or polyvinyl alcohol with mol. weight. 1OOOO, and / or carbohydrates with mol. Weight. 15O.

The concentration of organic matter in the aqueous medium is maintained in the range of 0.1-2.0 g / l.

The method is carried out as follows.

Microorganisms, yeasts or bacteria are cultivated in a fermenter equipped with a stirrer and a device for aerating the medium. Purified liquid paraffins or petroleum distillates are used as carbon source.

The aqueous nutrient medium contains the mineral sources of micro-anism necessary for growth. In an aqueous nutrient medium (ononKViTenbHo), a surfactant and orthopedic substance is introduced into the concentrate) —shy 0.1-0.2 g / p. Hydrocarbons and aqueous nutrient medium are introduced into the fermenter either separately or in mixture in the form of an emulsion. Emul sion is obtained by intensive mixing of the components. The process of cultivating microorganisms is carried out in a continuous manner. The suspension of microorganisms emerging from the fermenter is collected in a collection, where it is divided into three layers within 10 minutes; the top layer is hydrocarbon; and culture fluid; The medium Hnii layer is cultural; the bottom layer is the biomass of microorganisms and the culture fluid. The layers are separated. From the lower layer (heavy phase), biomass was isolated by known methods: decanting, (55 thrash, or other). The middle layer, containing elements of a destructive environment, surface-active J organic substances, can be deposited into the cultivation process. The upper layer (light phase) after some time, it is separated into hydrocarbons and the aquatic environment.The separation can be accelerated by heating or using conventional methods.Experm 1. In a fermenter with a stirrer and aeration system, the yeast) OilyChs; (l.iCTrnori r3v,. The source of carbon slu; k;) T | oil distillation with boil-off 15O -. The aqueous nutrient medium contains, in addition to the mineral components necessary for growth, 0.8 g / l of dextran and 0.8 g / l of surfactant obtained by adding 9 molecules of ethylene oxide to dodecanol. The residence time of the yeast in the fermenter is 5 hours. The yeast suspension leaving the fermenter is fed into the tank. The above liquor is added to the suspension, at a rate of 0.5 g per liter of suspension. The mixture is stirred and allowed to stand. After 15 minutes, the suspension is layered off into three layers, which are separated. 80d The upper layer (light phase) consists of hydrocarbons and from the spent culture liquid and is an emulsion. When heated to 6O, the emulsion decomposes. The middle layer is the spent culture fluid. It is returned to the culture process. The bottom layer (Tavela, ZZA) is a suspension of yeast cells in a culture liquid. The content of biomass in suspension is about 20%. Biomass is filtered and dried. Example 2. In a fermenter with a stirrer and aeration system, the yeast Ccsndido, ierwov dii is continuously cultivated. The source of carbon was pure n-paraffins with carbon nepi C.-C length, Aqueous nutrient medium contains in addition to the mineral components necessary for growth, 0.7 g / l of carboxymethylcellulose and 1.2 g / l of surfactant. A surfactant is obtained by adding 10 ethylene oxide molecules to dodecanol. The residence time of the yeast in the fermenter is 5 hours. The yeast suspension leaving the fermenter is fed into a settling tank. After about 15 minutes, the suspension is stratified into three layers, similar to those described in Example 1. After separation of the phases, the two upper ones are returned to the fermenter. The solid phase is thickened and the biomass is dried. Example 3. In the fermenter with a stirrer and aeration system, the bacteria EB 10c, are continuously cultivated: C MET B 395. The carbon source was oil distillation products with boil-off levels of 25 O - 3 70 c. The aqueous nutrient medium contains, in addition to the mineral components necessary for growth, 1.0 g / l of polyethylene oxide and 0.8 g / l of a surfactant substance similar to that given in 2. The bacteria are cultured in a fermenter for 5 hours. The bacterial suspension left the fermenter is fed into a container, where it is mixed with the above mentioned surface active substance, which is added in the amount of 0.3 g / l and then settled.

After settling for 30 minutes, the mixture is stratified into 2 layers. The top layer is an oil emulsion in an aqueous medium; the bottom layer contains bacterial biomass as a suspension in the culture fluid.

The top layer is separated from the bottom by decantation. Next, the bacterial suspension is concentrated by centrifugation. Condensed biomass is dried at.

As a result of the implementation of the method in the process of cultivation of microorganisms on hydrocarbons, when organic and surfactants are added to the medium, the biomass and the cultivation medium are separated, which greatly simplifies the subsequent release of biomass from the medium.

Claims (2)

1. A method of producing biomass, involving the aerobic cultivation of microorganisms in a nutrient medium, containing liquid hydrocarbons as a carbon source, a nitrogen source, necessary mineral sources of nutrition and surfactants, followed by biomass release by adding a mixture of surface-active and organic substances characterized in that, in order to simplify the process, the cultivation of microorganisms is carried out by adding the mixture used in the isolation of biomass, while polyethylene glycol or polyvinyl alcohol with mol. weight. 10OOO, and / or carbohydrate mol. weight. 150 2. The method according to p. 1, about tl and h and y and so that the concentration of organic matter in the aquatic environment of the Pdb is kept in the range of 0.1-2.0 g / l. Sources of information taken into account in the examination 1. USSR author's certificate in application number 23439О9, cl. C 12 C 11/24, 1976.