The method of automatic control of the process of growing microorganisms
(57) Abstract:The invention relates to the microbiological industry, and in particular to methods of automatic control of the process of growing microorganisms, and can be used in the production of bakery yeast. This method involves determining the rate of change of concentration of yeast suspension, comparing it with the rate of change of oxygen concentration in the exhaust gases and the rate of change of the temperature of the yeast suspension. However, depending on the comparison result, adjusting the air supply for aeration. This method provides the optimal process conditions for the cultivation of yeast and increase their output. 1 Il., table 1. The invention relates to the microbiological industry, and in particular to methods of automatic control of the process of growing microorganisms, and can be used in the manufacture of yeast, particularly baking.Known methods of automatic control of the process of growing microorganisms, providing for the regulation of air supply for aeration and temperature variations yeast suspension (and. C. N 488847, CL C 12 B 1/08, 1975, bulriss cultivation of yeast, as
not considered significant fluctuations reducing substances (PB) in the nutrient solution;
do not allow to capture the moment of decay aerobic process, when started anaerobic alcoholic fermentation inhibits the respiration of yeast and prevents the normal development and reproduction of yeast cells due to lack of oxygen;
not considered significant inertia and hysteresis control loop temperature control.Closest to the proposed method is a method of automatic control of the growth process of yeast.with. N 584033, CL C 12 B 1/08, 1977, bull. N 46) defining the rate of change of the temperature of the yeast suspension, comparing it with the preset negative value and, depending on the comparison result, correction of the air supply for aeration.The considered method has the following disadvantages:
management is carried out by indirect parameter is the rate of change of the temperature of the yeast suspension, without the basic parameter that determines the growth process of yeast - rate of change of the concentration of yeast;
Correction of the air supply to the aeration is carried out at a time when the value of ipred specified, a negative value that corresponds to the beginning of unwanted alcoholic fermentation, and therefore this mode is far from optimal;
the considered method can be used when implementing the "hard" technological programs, i.e., requires the prior definition of a negative value, and therefore not used in the conduct of the "flexible" process, taking into account, for example, disturbing effect on the quality of media received in trojanactualit the device.Object of the invention is the provision of optimum process conditions for the cultivation of yeast and increase their output.This object is achieved in that the proposed method is determined by the rate of change of concentration of yeast suspension, compared to the rate of change of oxygen concentration in the exhaust gases and the rate of change of the temperature of the yeast suspension and, depending on results of the comparison, adjusts the air supply for aeration.In the result of the search is found that in the existing technical solutions and automatic control of the process of growing microorganismal changes in the concentration of oxygen in the exhaust gases, especially in conjunction with the previously used parameter is the rate of change of the temperature of the yeast suspension. The use of these parameters in the proposed aggregate gives a new positive effect. Therefore, the proposed solution meets the criterion of "significant differences".The drawing shows a block diagram of a system that implements the proposed method.The system consists of a control object of drogenabteilung apparatus 1; the flow sensor 2 air supplied to the aeration in the apparatus 1; sensor the concentration of yeast suspension 3 in the device 1; sensor oxygen concentration 4, the exhaust gas; a temperature sensor 5 in the yeast suspension in the apparatus 1; differentiating elements 6-8; knobs 9-11; elements of comparison 12-14; a control device 15 and the actuator with the regulatory body 16 mounted on the supply line of air for aeration in the apparatus 1.The system works as follows.Information about the current value of the flow rate of air for aeration in the apparatus 1 is supplied to the control device 15, which is compared with a set value of the air flow for this race microorganisms coming to control the mi flow of air for aeration in accordance with the selected control algorithm generates a corresponding control signal, coming to the actuator with the regulator 16, which changes the air flow to the aeration apparatus 1.The system provides stabilization of air for aeration in the absence of disturbing influences on the control object. However, in the real process involves significant disturbance, and there is a need to adjust the air flow to the aeration for compensation of disturbing influences. The proposed method of automatic control takes this into consideration.To do this continuously measured current values of the concentration of yeast suspension X in the apparatus 1, the oxygen concentration in the exhaust gases Y and the temperature of the yeast suspension Z in the apparatus 1 by using sensors, respectively 3-5. The signals from the sensors 3-5 proportional to the current value of the concentration of yeast suspension X, the concentration of oxygen in the exhaust gases Y and the temperature of the yeast suspension Z goes into the differential elements 6-8, which are determined by the speed of their changes and produces signals proportional to these speeds, i.e.
With differentiating elements 6 and 7, the signals are sent to the comparison element 12, where they cravens specified, the maximum allowable process regulations for the relevant microorganisms, the value of1coming to the comparison element 12 from the generator 9. If the value at the output of the comparison element 12 will be 0 (zero). If the value of the difference between the comparison element 12 will determine their difference, i.e., and this value with the correct sign, is supplied to the comparison element 14, which receives the signal from the comparison element 13.Simultaneously, with the differentiating element 6 and 8, the signals supplied to the comparison element 13, where these signals are compared, and is determined by the difference of their values, i.e. the difference in this comparison element 13 is compared with a preset maximum allowable value2received on the comparison element 13 of the unit 10. If the value at the output of the comparison element 13 will be 0 (zero). If the value of the difference between the comparison element 13 will determine their difference, i.e., and this value with the correct sign will be on the comparison element 14.On the comparison element 14 compares two values1and2with regard to their characters. If signs 1and2the same (both positive or both negative), then the comparison element 14 B> different, the comparison element 14 defines their algebraic sum, and this summed signal is supplied to the control device 15 as a corrective signal. If1=2and their signs are the same, then the control unit 15 serves to 0 (zero), i.e., the correction signal is missing.The control device 15, in accordance with the magnitude and sign of the signal with the comparison element 14, adjusts the control action to the actuator 16, which will change the flow of air for aeration in the apparatus 1.Let us consider in more detail the operation of the elements of comparison 12-14.For example, the magnitude of the rate of change of biomass concentration greater than the rate of change of oxygen concentration in the exhaust gases, i.e., (this situation can occur if the General condition of the process of cultivation of microorganisms, taking into account the physiological capabilities of the population, exceeds the amount of oxygen supplied to the device, for example, due to a temporary malfunction of part of the air-distributing device, and others). Therefore, the comparison element 12 is determined by the difference and compares the absolute value with a specified value1. Then, when the river is 14 receives a certain value 1, with the sign +. This sign requires an increase in the supply of air for aeration in proportion to the value of1.
At the same time, for example, the value of the rate of change of temperature of the yeast slurry greater than the rate of change of concentration of yeast suspension ie (this can happen if there are disturbances on the temperature channel, for example, clogging or other temporary malfunction in the coolant supply to the apparatus, the temperature of the air supplied to the aeration and others). Then in the comparison element 13 will determine the difference and will be equal, in absolute value, with a specified value2. If the comparison element will determine the value of |*2|-|2| = -2that will come to the comparison element 14, and the sign "-" in2requires reducing the air supply to the aeration proportion to the value of2.
Thus, the comparison element 14 receives the value of1and2with different absolute values and signs.If in the considered case |1| > |2|, then the comparison element 14 will subtract from a larger value to a smaller, i.e., |1|-|2and, considering the sign of a larger value will adjust the control signal, coming to the actuator 16, the increase of air consumption for aeration in proportion to the magnitude of the difference |1|-|2|.
If, for example, |1| < |2|. the comparison element 14 will determine the difference |1|-|2and, considering the sign "-", the control unit 15 adjusts the control signal to reduce the consumption of air for aeration in proportion to the magnitude of the difference |1|-|2|.
If, for example, |1| = |2and their signs are different, the control unit 15 does not receive the correction signal as at the output of the comparison element is 0 (zero), i.e., disturbances that come through different channels, mutually compensate each other.Now suppose, for example, that the comparison element 14 receives two values 1and2, different absolute values, but with the same characters (for example, with " - " sign. The comparison element 14, after comparing absolute values |1| and |2| miss on control device a signal with a large value, i.e., the effect of perturbation on the channel with the smaller value is already accounted for, and control unit 15 generates a corrective signal (reduced air flow) in salicylidene apparatus of the type WDA-100 commodity production stage yeast "In" using a blower machine TV-200-1,4 with the use of technological regulations, adopted at the Voronezh yeast plant, in the accumulation period. To implement the method, we used the following automation tools:
sensor the concentration of yeast suspension - refractometric sensor type a1-EDR Converter MP-P;
the flow sensor air - induction flow meter type IL-11;
the temperature sensor yeast suspension - resistance thermometer type SCI-XI;
the sensor of oxygen concentration in the exhaust gases - meter based KMC-59;
differentiating elements differentiator type D-P;
elements of comparison and measurement units And type-UE;
referencing software Adjuster type PD-44 the MIND;
the controller is an electronic controller type WP1-pack.The results of the experiment are shown in table.From the experiment it is seen that only in the cumulative period using the proposed method can improve the yield of yeast is about 5%.Therefore, the proposed method can correctly take into account perturbations on different channels based on their magnitudes and signs, as well as taking into account their mutual compensation and thereby ensures optimal process conditions for the cultivation of yeast and is, for example, Baker's yeast, which consists in regulating the air supply to the aeration correction, measuring the temperature of yeast suspension and determining the rate of change of this temperature, characterized in that it further determine the rate of change of oxygen concentration in the exhaust gases and the rate of change of concentration of yeast suspension, the last value is compared with the rate of change of oxygen concentration in the exhaust gases and the rate of change of the temperature of the yeast suspension, the results of the comparison are compared among themselves, and correction of the air supply to the aeration is carried out in dependence on the result of the last comparison.
FIELD: biotechnology and microbiological industry.
SUBSTANCE: invention concerns governing periodical air-intake biotechnological process carried out in bioreactor. Method comprises measuring oxygen content in effluent gas, working volume of culture medium, concentration of biomass, and concentration of intermediate product of its vital activity. Measured parameters allow specific oxygen consumption rate and velocity of intermediate product concentration change to be determined to enable regulation of feeding air used in aeration, supplying nutritional medium, and agitating culture medium. Moreover, temperature of culture medium, temperature of supplied and withdrawn cooling agent, and consumption of the latter are measured to use these parameters for determining biomass heat release rate and velocity of intermediate product amount change. The two latter parameters enable regulation of feeding air used in aeration and supplying nutritional medium. The following characteristics are thus improved: elevating power by 8.1%, maltase activity by 7.9% and resistance by 7.4%.
EFFECT: enhanced efficiency of governing biotechnological process and improved qualitative characteristics of process.
FIELD: chemistry; biochemistry.
SUBSTANCE: proposed method can primarily be used in biotechnology, biochemistry and industrial microbiology. Fermentation apparatus are used to study growth and metabolism of microorganisms and for solving several other tasks. Proposed solution involves measurement within given time intervals of flow of liquid and gaseous media through a fermentation vessel at the beginning of the fermentation process and during the said process after selected time intervals necessary for measuring heat production of microorganisms and evaluating destabilising inputs of heat power from operation of apparatus for moving the culture fluid. Heat production is calculated as the increment of current values of heat power to the initial value of the measured heat power while making corrections for the effect of the said destabilising inputs. The method is realised in a fermentation apparatus in which a fermentation vessel is placed inside a controlled thermostating screen and is fitted with an additional mixing device for controlling temperature of the fermentation vessel. Pipes running to the fermentation vessel are in thermal contact with the controlled thermostating screen.
EFFECT: more accurate measurement of heat production of microorganisms in a fermentation vessel in continuous or periodic processes.
4 cl, 5 dwg, 1 tbl
SUBSTANCE: initial nutrient medium together with an inoculated autotrophic microorganism is supplied from a technological container into an input section of a photobioreactor with forming a suspension film of a photoautotrophic microorganism flowing down by gravity on an internal surface of transparent cylindrical tubes. Simultaneously, mixed air and carbon dioxide are reverse-flow supplied inside the tubes with using sleeves with suspension film outflow. The photoautotrophic microorganism suspension flowing in the internal surface of the transparent cylindrical tubes gets into a light section wherein it is continuously illuminated with a fluorescent tube. From the transparent cylindrical tubes, the photoautotrophic microorganism suspension flows down in an output section of the photobioreactor wherein it is bubbled to saturate the cells with carbon dioxide additionally and illuminated with a horizontal toroidal lamp. An external surface of the transparent cylindrical tubes is sequentially cooled in cooling air in the light section and in cooling water in the cooling section with cooling air and cooling water flowing in the respective recirculation loops. The photoautotrophic microorganism suspension is added with a nutrient medium of main and correction flows supplied into a technological container at first and then into the suspension recirculation loop at the input of the input section of the photobioreactor. Waste mixed air and carbon dioxide are supplied from the photobioreactor into the mixer by means of a compressor through the mixed air and carbon dioxide recirculation loop and temporarily collected in a gas tank. Post-bubble foam is continuously discharged from a lower section of the photobioreactor into an anti-foaming separator and separated into a suspension supplied into the input section of the photobioreactor and mixed air and carbon dioxide combined with waste mixed air and carbon dioxide in a regulation loop, while being temporarily collected in the gas tank and supplied into the mixer with extra saturation of waste mixed air and carbon dioxide with a required amount of carbon dioxide. Carbon dioxide saturated mixed air and carbon dioxide are discharged from the mixed by two ducts one of which being a main flow is reverse-flow directed inside the transparent cylindrical tubes; the other one is supplied into the output portion of the photobioreactor when bubbling the suspension. From the output portion of the photobioreactor, the microorganism suspension is discharged from the suspension recirculation loop with intermediate vented out oxygen release accompanying a cultivation process with using a desorber; another portion of the photoautotrophic microorganism suspension is discharged in a finished biomass collector to be measured for the required values for the purpose of creating optimal conditions for photoautotrophic microorganism cultivation.
EFFECT: invention provides higher effectiveness of photoautotrophic microorganism cultivation, enabled integration of the presented method into the current production lines, improved energy efficiency and performance of photoautotrophic microorganism cultivation.
2 ex, 1 dwg