SU1467085A1 - Method of automatic control of cyclic process of continuous cultivation of microorganisms - Google Patents

Abstract

The invention relates to the microbiological industry, in particular, to methods for the automatic control of the processes of the continuous cultivation of microorganisms, and can be used, for example, in the production of fodder yeast. The aim of the invention is to increase the biomass yield. The method of automatic control of the cyclic process of continuous cultivation of microorganisms involves the regulation of the supply of the substrate in the main and additional streams and the supply of water to the fermenter depending on the level of measurements of the rate of oxygen consumption by the microorganisms and the consumption of the supplied substrate. The amount of oxygen and substrate consumed for the cultivation of microorganisms is determined by the ratio of these parameters to determine the integral indicator of the process economy, while the substrate is fed in an additional stream using pulsed doses, and in real time they search for the maximum value of the integral indicator of the process economy. by controlling the frequency of the doses given in the additional stream. Compared with the prototype, the method allows to synchronize the process of microbial biosynthesis by pulsed substrate feeding, make more rational use of the substrate and increase the biomass yield by an average of 7.3%. 1 il. about sl 4 o 00 ate

Description

The invention relates to the microbiological industry, in particular, to methods for automatically controlling the processes of continuous cultivation of microorganisms, and can be used, for example, in the production of fodder yeast.

The purpose of the invention is to increase the biomass yield.

The method is as follows.

With the continuous cultivation of microorganisms, pulsed introduction of the substrate allows synchronization of the process of biosynthesis and more rational use of the substrate, which increases the efficiency of the process. In this case, it is advisable to introduce such. Amount of substrate, which is completely

The cell must be consumed during the course of the general session, and the frequency of the doses administered is approximately equal to the generation period. The substrate is consumed in a more balanced manner, when the dose of the substrate is not injected in pulses, but sequentially, at a certain feed rate. For each cultivation process, there is an optimal mode of fractional feed of the substrate (the characteristic parameters are dose rate and feed rate |, follow-up rate) which provides for

iCMbie indicators of the cultivation process, for example, the maximum cost-effectiveness of the process. Due to the nonstationary nature of the process, it is only possible to establish in advance the values of these parameters. They can be refined by searching for the maximum economic efficiency of the process in real time.

; When implementing this method, the amount of the substrate dose and the rate of its supply is set experimentally, maintaining the frequency of the follow-up doses given equal to the average: the division of cultured inpH cells in the division of the optimal steady-state cultivation conditions. Pick up the value; substrate dose and feed rate so as to ensure maximum efficiency of the process. For the selected: dose and optimum speed, its supply in real time further searches for the maximum economy of the process by controlling the frequency of the delivered doses. To do this, it is necessary to continuously determine the efficiency of the process during the process.

The profitability of the process can be judged by the integral indicator

,

one

jQsoSodf

. 50

de I - integral indicator of the efficiency of the process

Q is the rate of consumption of oxygen by microorganisms,

Q gg is the flow rate of the supplied substrate tj m;

S g - the concentration of the input substrate,

T is the integration period,

"

five

0

0

50

45

50

tj

since the amount of oxygen consumed is proportional to the increase in biohm with c: III,

Therefore, the frequency of the supplied substrate doses is controlled in such a way (in order to maximize the integral indicator of the process economy.

The drawing shows a system that implements the proposed method.

The system consists of a fermenter 1, a substrate flow control circuit for the main flow, including a flow sensor 2 connected through a regulator 3 to an actuator 4 installed on the substrate supply line, a fluid level control loop in the fermenter, including a level sensor 5, a regulator 6 and the actuator 7 on the dilution water supply line and the regulation circuit of the substrate supply of discrete doses of the substrate, including the microorganism consumption sensor 8, the output of which through the integrator

9 connected to the first input of block 10, the sensor 11 of the flow rate of the supplied substrate, the output of which through the integrator 12 and block 13 multiply is connected to the second input of the block 10 of division, and the output of the latter through the extreme controller 14, programmed timer 15 and time relay 16 connected to the pumping means 17. In addition, the circuit contains a block 18 synchronization, the output of which is connected to the integrators 9, 12 and the block

10 divisions, and the setpoint adjuster 19, the concentration of the input substrate, which is connected to the multiplication unit 13.

The system works as follows

The substrate supply control loop, consisting of a flow sensor 2, a regulator 3 and an actuator 4 installed on the substrate supply line along the main flow, maintains the background concentration of the substrate in the fermenter necessary to maintain the life of 1 Scrottles in the time intervals complete the fermentation of the previous dose before the next dose of the substrate is delivered, t, e. to eliminate the deep lm1-ta on the substrate. The amount of continuously supplied substrate is the amount of substrate consumed to maintain the viability of microorganisms under given culture conditions.

The control loop for the supply of discrete doses of the substrate along the additional flow ensures the search for the maximum efficiency of the process by controlling the frequency of the delivered doses.

Sensor 8 measures the rate of consumption of oxygen by microorganisms. The signal from sensor 8 is supplied to an integrator 9, in which the amount of oxygen consumed to cultivate microorganisms for a given period of time is calculated. Sig1467085

ten

the stroke of the dividing unit 10, which characterizes the economy of the process, is fed to the extreme controller 14. The extreme controller controls the operation of the program timer 15, which determines the frequency of the substrate doses given. Extreme controller 14 searches for the maximum value of the integral indicator of the process economy by correcting frequency of doses given. The signal from timer 15 triggers the time relay 16, the output from integrator 9 output is proportional, the amount of feed-dose depends on the amount of biomass grown and switches on the pumping means, is fed to the first input of the block 10 17, through which the dose of substrate (Targets. Also, the sensor of the measured emitter is fed to the fermenter. From the characteristics of the flow of the supplied substrate. The signal of the sensor 11 is fed to the integrator 12, in which the amount of consumed substrate liquid is counted for a given period of time. Periods and integrating integrators 9 and 12 are equal. The signal from the output of integrator 12 is fed to multiplication unit 13, which multiplies the input substrate concentration signal given by setter 19, and from the output of multiplication unit, the signal proportional to the amount of consumed substrate is fed to the second the input of the dividing unit 10, in which the ratio of the amount of oxygen to the amount of substrate, i.e. the integral indicator of the process efficiency, is determined. The operation of the integrators 9, 12 and the dividing unit 10 is controlled by the synchronizing unit 18, which sets the integrating period for the pumping means, and the substrate dose rate is determined. The magnitude of the dose delivered and the rate of its delivery are established experimentally for this process. The initial frequency of the delivered doses is equal to 25 average period of cell culture dividing under optimal stationary cultivation conditions. I

Thus, when implementing the proposed method, an optimum fractional feed mode of the substrate is established, which ensures maximum efficiency of the process under these cultivation conditions and increases the yield by 7.3%.

35

Formula FROM Gain

Method for automatic control of cyclic continuous process

Vani. I

After the end of this period, syncronization block 18: generates a control signal by which the signals of the integral sum from the outputs of the integrators 9 and 12 are fed to the division block 10, resetting the integrators and starting the division block. The integration time depends on the inertia of the process and is equal to an integer number of periods of doses delivered (for example, a change in the frequency of the doses delivered causes a transition process, after which a new value of the integral indicator of the process economy is established, the integration time is the time of the transition process) block 18 synchronization with the timer output 15. The signal from you1467085

the stroke of the dividing unit 10, which characterizes the economy of the process, is fed to the extreme controller 14. The extreme controller controls the operation of the program timer 15, which determines the frequency of the substrate doses given. Extreme controller 14 searches for the maximum value of the integral indicator of the process economy by correcting frequency of doses given. The signal from timer 15 triggers a time relay 16, the output of which depends on the value of the supplied dose and turns on pumping means 17, through which the dose of the substrate is fed to the fermenter. From harak-

The dose depends on the size of the delivered dose and includes pumping means 17, through which the dose of the substrate is fed to the fermenter. From harak-

Fluid flow rate depends on substrate dose rate. The magnitude of the dose delivered and the rate of its delivery are established experimentally for this process. The initial frequency of the delivered doses is equal to 5 to the average period of cell culture dividing under optimal stationary cultivation conditions. I

Thus, when implementing the proposed method, an optimum fractional feed mode of the substrate is established, which ensures maximum efficiency of the process under these cultivation conditions and increases the yield by 7.3%.

The dose depends on the size of the delivered dose and includes pumping means 17, through which the dose of the substrate is fed to the fermenter. From harak

35

Formula FROM Gain

The dose depends on the size of the delivered dose and includes pumping means 17, through which the dose of the substrate is fed to the fermenter. From character- A method of automatic control of the cyclic process of continuous

0 cultivation of microorganisms, which involves dividing the flow of the supplied substrate into the main and additional, supplied with doses, regulating the supply of the substrate in the main and additional flows and water, and measuring the rate of oxygen consumption by microorganisms, characterized in that, in order to increase the biomass yield,

0 total consumption of the supplied substrate and determine the amount of oxygen and substrate consumed for the cultivation of microorganisms, and their ratio, and the regulation of the flow of the substrate in the additional flow is carried out depending on the maximum value of the integral value of the ratio of the amount of oxygen consumed for cultivation microorganisms, to the amount of substrate consumed for cultivation

microorganisms by changing the frequency of the delivered dose.

Editor A. Kozoriz

Compiler GoBogacheva

Tehred L.OliynykKorrektor S.Shekmar

Order 1116/21

Circulation 500

VNII11I State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, 4/5 Raushsk nab.

Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101

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Claims (1)

Claim A method for automatically controlling the cyclic process of continuous cultivation of microorganisms, comprising dividing the flow of the supplied substrate into the main and additional, supplied in doses, controlling the supply of the substrate in the main and additional flows and water, and measuring the oxygen consumption rate by microorganisms, characterized in that, in order to increase the biomass yield, measure the total flow rate of the supplied substrate, the frequency of the doses administered causes a transient process, after which is established A new value of the integral indicator of econo is added and the amount of oxygen and substrate consumed for the cultivation of microorganisms, and their ratio are determined, and the regulation of the supply of the process sub-static, the integration time is the time of the transition process). The frequency signal of the delivered doses is supplied to the synchronization unit 18 from the output of the timer 15. The signal from Does the 55th feed in the additional flow carry out, depending on the maximum value of the integral value, the ratio of the amount of oxygen consumed for cultivating microorganisms to the amount of substrate consumed for cultivating microorganisms _? by changing the frequency of the dose given.