DD220331A1 - MICROBIOLOGICAL METHOD FOR REDUCING THE STICK POINT OF DIESEL FUEL - Google Patents

Abstract

THE INVENTION CONCERNS A MICROBIOLOGICAL METHOD FOR REDUCING THE STICKING POINT OF DIESEL FUEL BY CONSERVING MICRO-ORGANISM POPULATION, WHICH MAY, IN PARTICULAR, BE INCLUDED IN PRODUCTION LINES OF THE PETROL-CHEMICAL INDUSTRY. THE OBJECTIVE OF THE INVENTION IS TO REDUCE THE STICK POINT OF DIESEL FUEL TO LESS THAN -30 DEGREE CELSIUS. THE OBJECT OF THE INVENTION IS TO DEVELOP A PROCEDURE WHICH IS UNIQUE AND ALLOWS THE REDUCTION OF THE POINT OF STAGE FOR THE MANAGEMENT OF THE DELIVERY TO DIESEL FUEL. IN THE PURPOSE OF THE INVENTION, THE TASK IS PERFORMED BY PERIODIC DOSAGE OF THE DIESEL FUEL INTO THE FERMENTOR, WHERE THE REDUCTION OF THE DIESEL FUEL FEEDING SPEED IS CHARGED AS A RESPONSIBILITY TO THE RESERVATION OF THE PROCESS.

Description

Title of the invention

Microbiological process for lowering the pour point of diesel fuel

Gsgebiet applicatio of the invention

The invention relates to a microbiological process for lowering the pour point of diesel fuel by breeding microorganism populations, which can be fitted in particular in production networks of the petrochemical industry

 The procedure is classified in the IPK C 12 I.

Characteristic of known technical solutions

There is a method for the production of feed yeast known (DD-WP 105 825), 'consisting of two stages. In the first stage, yeast is cultured aerobically and continuously at a constant petroleum still feed rate. The 1 × stage fermentor effluent is passed to a second fermenter and culturing is continued under the same fermentation conditions. By applying this method, a pour point of the petroleum distillate after the 2nd fermentation stage up to - 30 ⁰ C at a Erdöldestillatanteil on the fermentation medium of 10 me .-%, an n-paraffin content in the petroleum distillate of 38 Ma. ~% and a total dwell time

time of 12 hours. A disadvantage of the cost of the process, the high expenditure on equipment affects. A realization of pour points of the petroleum distillate lower than - 30 ⁰ C would be possible in principle, but associated with an increase in the total residence time and thus a reduction in the output of the plant.

the jubilee load

The aim of the invention is the lowering of the pour point of

Diesel fuel to less than - 30 ⁰ C. Presentation of the essence of the invention

The object of the invention is to develop a one-step process which, by way of the control of the supply of diesel fuel, allows the stock

ρ of the diesel fuel to lower than - 30 ⁰ C _β

The Aufgäbe is inventively by periodic dosing of the diesel fuel in the fermentor, in which a microorganism population continuously or semicontinuously for the production of microbial Produkt®9 especially of protein-containing feeds, aerobic diesel fuel or mixtures of diesel fuel and other carbon substrates such as carbohydrates, alcohols or organic acids The solution according to the invention provides for a periodic reduction in the diesel fuel feed rate with respect to the stationary fermentation in the case of continuous fermentation as a function of the doubling time of the microorganisms and the residence time.

The diesel fuel supply is preferably reduced to one half of the steady state value over a period of 1 to 5 hours with a continuous culture time of 5 hours (0.2 to 1 times the residence time).

The period of the change in the diesel fuel feed rate is a function of the degree of reduction of the diesel fuel range 3 _f 5 to 12 hours at a residence time of 5 hours (doubling time to 2.5 times the residence time).

Borderline cases are:,

- Period 4h

Interruption of diesel fuel supply 1 h per / dd residence time 5 h

- Period 12h

Reduction of diesel fuel supply to half in the period of 7 h per period residence time 5h

The low-level diesel fuel accumulates continuously in the fermentation and is separated from the Fermehtorablauf by separation · The solution of the invention provides for semi-continuous fermentation, the supply of diesel fuel at intervals equal to or greater than the doubling time of the microorganisms. At the same time half of the fermentation medium is removed from the fermenter and the low-level diesel fuel separated by separation. When replacing half of the fermentation medium in 6 h intervals, it will test for diesel fuel and aqueous medium containing another carbon

may contain carbon source, a pour point of the diesel fuel is less than - 40 ⁰ C was reached · s The invention will be illustrated by the following examples,

Example V

The yeast strain Lodderomyces elongisporus DEH 15 was grown continuously and aerobically on diesel fuel (DK) in a 11 m »submerged jet reactor with a <L value of 1 ₉ 25 with a residence time of 5 h. The DK had an n-paraffin content of 12 lfe. -%. The aqueous Mhrmedium contained per liter 3600 mg of ammonium nitrogen, 500 mg Phosphatphösphor, 500 mg ^v potassium in K ₂ CO _3, 50 mg of magnesium in MgSO * · 7 H ₂ O, and trace salts in sufficient amounts The fermentation parameters were set as follows: temperature 32 ⁰ C

pH 4.2 (control with 10 % NaOH)

Aeration rate 50 l / kgh reactor capacity 10 000 kg (10 t)

In order to obtain low-level DK, the aqueous medium, the lye, water and the DK were fed to the yeast population in the permentor according to the following schedules (process variants I-VIII).

Variant ^ I

- Periodic DK ~ supply and keeping constant the residence time

- Period of change of DK ~ feed 4h

- Schedule of the supply of nutrients

per period feed rates (l / h)

DK Myr solution water / lye

lh 0 800 1200

3h '476 800 800

- mean DK concentration 15% by mass

- Periodic DK supply and change in the residence time

- Period of change of DK feed 4h

- Schedule of currency feed

per period feed rates (l / h)

DK Nutrient Lasser / Lye 1h 0 800 900

3h 476 800 900

- mean DK concentration 15 Ma. -% ¹⁰

- Periodic DK supply and keeping constant the residence time

- Period of change of DK supply 6h

- Timing of nutrient supply

per period feed rates (l / h)

DK nutrient solution water / lye 2h 0 '800 1200

4 hours 476 800 800,

- mean DK concentration 13.3 'Ma.-55 20

- Periodic DK supply and change in the residence time

- Period of change of DK supply 6h - Timing of nutrient supply

per period feed rates (l / h)

DK nutrient solution water / lye

2 h 0 800 933

4 hours 476 800 933

- mean DK concentration 13 »3% by mass

Variante_V

Periodic change of the DK supply and keeping the residence time constant

, ': - Period ^ ndauer the change in DK-feeding 12 hours - Schedule of nutrient intake,

per period feed rates (l / h)

DK nutrient solution, water / lye 5 h 476 -. 800,800

7 h 238 _t 800 1000

- 'mean DK concentration 14 ₉ 2% by mass

Periodic change of the DK supply and variability of the residence time

- Period of change of the DK supply 12 h - Timing of the nutrient supply

per period feed rates (l / h)

DK nutrient solution water / lye

_; 5 Ii .476 800. 917

7 h 238 800 917

- mean DK concentration 14.2 Efe .-%

periodic DK supply and keeping the residence time constant,

- Period of change of the DK supply 12 h - Timing of the nutrient supply

per period feed rates (l / h)

DK nutrient solution water / lye 1h 0 '800 1200

5h 476 800 800

- ^ f). ι ^ Vi Old anr,

- mean DK concentration 13.3% by mass.

IäEiSSiS-ϊϊϊϊ

- Periodic DK supply and change of the residence time

- Period of change of DK supply 12 h - Schedule of nutrient supply

per period feed rates (l / h)

DK nutrient solution water / lye 1h 0 800 933

5h 476 800 933

6h 238 800 933

- mean DK concentration

When using the variants I to VI, a pour point of the DK was reached after the fermentation of - 41 ⁰ C. The variants were VII and VIII for obtaining diesel fuel having a pour point of - 45 ⁰ C used the mean biomass formation rate was 2.9 x g / tojh The specific n-paraffin consumption was 0.9 g / g.

Example 2

The yeast strain Lodderomyces elongisporus was grown as described in Example 1.

The aqueous nutrient solution contained, in addition to inorganic compounds, 14 g of sucrose / l or 28 g of molasses / l. By periodic supply of diesel fuel during fermentation, its pour point could be lowered to values of less than r- 40 ⁰ C. The biomass formation rate was about 4 »3 g / kQh.

Example 3

The yeast strain Lodderomyces elongisporus was semi-continuous and aerobic to diesel fuel in a 11 m

Rührreaktor bred with a content of 10 t fermentation medium "The diesel fuel and the aqueous nutrient medium were j as described in Example 1, composed β

The fermentation conditions were chosen analogously to Example 1 "

At the beginning of the experiment, 4000 l of aqueous nutrient medium, 4000 l of water and 2400 l of diesel fuel were introduced into the reactor, ventilated, heated and inoculated with yeast suspension. The yeast population was cultivated intermittently until the dissolved acid concentration increased to 7 ppm. Thereafter, 5200 l of fermentation medium were removed from the fermenter and 120 l of diesel fuel, 2000 l of aqueous nutrient medium and 2000 l of water were added to the fermentor. The DK fermentation was continued for 6 h and then again remove half of the fermentation medium from the reactor and replace it with diesel fuel and aqueous nutrient medium. «

The process continues as described. * In this way the following process codes have been reached j

Pour point of diesel fuel - 45 ⁰ C Biomass formation rate 2 ₉ 8 g / tejh

Claims (6)

invention claim Microbiological process for lowering the pour point of diesel fuel to less than - 30 ° C, characterized in that diesel fuel of a microorganism population, which is able to use components of the diesel fuel, in particular paraffins, periodically in function of the mixing time of the microorganisms and the residence time of the cultivation is supplied, wherein the period of the diesel fuel supply is equal to or greater than the doubling time of the microorganisms. 2. The method according to item 1, characterized in that the microorganism population on diesel fuel or combinations of diesel fuel with coal material substrates which are also used by the microorganism population. 3 · Method according to item 1 and 2, characterized in that the diesel fuel supply in continuous fermentation periodically in the period of 1 to 2 hours (0.2 to 0.4 times the residence time) interrupted at a residence time of about 5 hours is and the period is on the order of the residence time. 4. The method according to item 1 and 2, characterized in that in continuous fermentation, the diesel fuel supply periodically to half in the time r ··· 7 hours (1.4 times the residence time) is reduced and the period is 12 hours (2.5 times the residence time). 5. The method according to item 1 and 2, characterized in that the diesel fuel feed in continuous fermentation is changed with a period of 12 hours, wherein per period, the diesel fuel feed rate is interrupted for 1 hour, 5 hours corresponds to the value of the stationary fermentation and 6 hours is reduced to half. 6. The method according to item 1 and 2, characterized in that diesel fuel in semicontinuous fermentation of the microorganism population at time intervals which are 1 to 4 times the doubling time of the microorganisms supplied.