Apparatus for measuring the parameters of a suspension of microorganisms in a photobioreactor

Abstract

The invention relates to measuring devices for monitoring the characteristics of biological suspensions. A combined apparatus consists of a housing, within which a temperature sensor, an emitter, a photodetector of a fluorometer, a photodetector of a turbidimeter, and an electronic control unit are arranged. The housing is hermetically sealed and formed in the shape of a U, the vertical parts thereof forming a channel. The parallel walls of the channel contain openings in which glass sealing panes are mounted. Disposed inside one vertical part of the housing is a frame for optical instruments, in which the fluorometer photodetector and the emitter are mounted in such a way that the optical axes of the emitter and the fluorometer photodetector intersect. Mounted in front of the fluorometer photodetector and the emitter are light filters. The turbidimeter photodetector is disposed inside the other vertical part of the housing. The electronic control unit and the temperature sensor are disposed in the horizontal part of the housing. Mounted on the outer walls of the housing are at least two fastening brackets. The technical result of the invention consists in automating the measuring process and increasing the accuracy of the measurements taken and the reliability of the data obtained, while reducing the manufacturing cost of the apparatus.

Description

[0001] DEVICE FOR MEASURING PARAMETERS OF MICROORGANISMS SUSPENSION IN A PHOTOBIOREACTOR

[0002] The claimed invention relates to the fields of electronics, optics and biotechnology, namely to measuring devices for continuous multiparameter monitoring of the physicochemical characteristics of biological suspensions (microorganisms and culture fluid) cultivated in a specialized device (photobioreactor) in an industrial manner, as well as to devices that control the development of phototrophic microorganisms in such areas as:

[0003] • water purification, including wastewater;

[0004] • enrichment of mineral ores;

[0005] • food industry;

[0006] • microbiological industry;

[0007] • agriculture;

[0008] • petrochemicals.

[0009] To ensure the efficient operation of microorganism culturing devices, it is necessary to have objective information about the state of the object during the process, as well as the ability to control the process. Control over the stages of microbiological synthesis is carried out in two ways. The first is with the help of primary information sensors installed directly in the culturing device or on the communications adjacent to it, the second is with the help of laboratory analyses of suspension samples periodically taken from the photobioreactor. It is obvious that for an industrial installation the use of information sensors is a priority. This allows:

[0010] • take measurements much more frequently;

[0011] • eliminate the influence of the human factor;

[0012] • eliminate the requirement for the presence of qualified personnel;

[0013] • eliminate the time interval between sampling, obtaining measurement results and entering information into the information system - in the sample taken and in the culturing device, biological suspensions change at different rates;

[0014] • perform simultaneous measurements at several points (due to the large volumes of the photobioreactor, the suspension parameters differ);

[0015] • ensure data consistency - when the measured data (fluorescence intensity, cell concentration, temperature, etc.) relate to the same object under study; • place the measuring device inside the suspension volume - water (weak salt solution) shields the measuring device from external electromagnetic fields.

[0016] The main parameters of the suspension that need to be continuously monitored are the state of the photosynthetic apparatus of microorganisms and their concentration (see, for example, Babin M. Phytoplankton fluorescence: theory, current literature and in situ measurementZ / Real-time Coastal Observing Systems for Marine Ecosystem Dynamics and Harmful Algal Blooms: Theory, Instrumentation and Modelling I Ed. M. Babin, CS Roesler, JJ Cullen. Paris UNESCO Publishing, 2008. URL: https: / / unesdoc.unesco.Org / ark: / 48223 / pf0000160000). To determine the state of the photosynthetic apparatus of microorganisms, the so-called "variable" chlorophyll fluorescence (relative increase in fluorescence intensity during light saturation of photosynthesis processes) of microorganism cells is measured. And to determine the concentration of cells, the optical density of the suspension is measured, which directly depends on the concentration.

[0017] Often, the use of microorganisms (microalgae) is limited by cost factors (cost price). One of the cost factors is the cost of the photobioreactor equipment, an essential part of which are measuring devices, such as a fluorimeter and an optical density sensor. These devices are expensive, but they consist of similar elements: a power supply (voltage converter), a controller, an interface module, an emitter, a light filter, a detector, a signal amplifier, an analog-to-digital converter, and a housing.

[0018] A device for continuous multiparameter monitoring of the physicochemical characteristics of biological suspensions is known (RU Patent No. 2786399, published on 20.12.2022), which comprises a housing in which a cell with at least six measuring channels is located, allowing the parameters of biological suspensions to be determined based on the measured optical characteristics, wherein one of the channels is intended for measuring oxygen, a power source, a magnetic stirrer located in the cell, a heater of the analyzed substance and a temperature sensor located in the cell, an electronic control board, five optical radiation sources installed in the measuring channels and five optical radiation recorders, also installed in the measuring channels, wherein the optical radiation recorders are connected to the inputs of the amplifier unit and analog-to-digital converters, the output of which is connected to the input of the recording device, wherein at leastthe oxygen sensor is an assembly containing at least one Y-shaped fiber bundle with a composite core, composed of two physically mixed fiber bundles intended for separating the optical paths of excitation and recording of the optical signal, wherein an excitation radiation emitter and a light filter are successively placed opposite the end of the first fiber bundle of the Y-shaped fiber bundle, and a light filter and a photodetector are successively placed opposite the end of the second fiber bundle of the Y-shaped fiber bundle, and a device for placing the analyzed sample is located opposite the common end of the fiber bundle, and the power source is connected to all power-consuming elements of the device. The following may be attributed to the disadvantages of the device:,

[0019] • the system does not contain photofilters that allow only the fluorescence spectrum to pass through;

[0020] • the specified device does not measure the optical density of the suspension and does not ensure the consistency of the obtained data;

[0021] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0022] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0023] • high cost of the device due to the fact that its light-guiding part is not mass-produced, and individual production does not allow for the provision of identical technical characteristics.

[0024] A photometer is known (RU Patent for Utility Model No. 75473, published on 10.08.2008), combining the capabilities of a fluorimeter and a photocolorimeter. The device contains a source of excitation light energy, an optical system, a cuvette closed with a lid and a photodetector, equipped with an additional external optical cell with a lid and two flexible light guides made of fiber optics. The light guides are fixed in the cuvette lid using guide metal tubes in such a way that their ends are strictly directed into the windows with the radiation source (primary light guide) and the photodetector (secondary light guide). The opposite ends of the light guides are fixed in the external optical cell using removable light guide holders, with the possibility of installing them at both an angle of 90° and an angle of 180°. The covers of the cuvette and the outer optical cell are provided with holes for the light guides, which are light-sealed with rubber seals. The following can be attributed to the disadvantages of the photometer:

[0025] • due to the rapid attenuation of the intensity of the exciting light depending on the distance in the thickness of the cell suspension and the low luminosity of the fluorescent cells, fluorescence will be observed only at a point located on the axis of the optical system immediately after the sealing glass. Therefore, the intersection of the optical axes of the optical photosystem and the photodetector should be at the point of the glass / liquid interface.

[0026] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0027] • the system does not contain photofilters that allow only the fluorescence spectrum to pass through;

[0028] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0029] • the specified device does not measure the optical density of the suspension, its temperature and does not ensure the consistency of the obtained data.

[0030] A photometer is known (RU Patent for Invention No. 2176384, published on 27.11.2001), comprising an optically coupled light source, a light beam former, interference light filters, an optical distributor, a plate and a device for receiving radiation. In addition, the photometer comprises a light flux switch with a rotor rotating inside a fixed housing, in which a flat mirror or light guide is fixed, and M fixed illuminating light guides are fixed in the housing, where M is the number of cells in a column or row of the plate. To measure optical density or fluorescence with one photodetector, the switch rotor may contain two light guides, and in the housing - additionally M measuring light guides and one common output light guide, optically coupled with one photodetector for alternately measured light fluxes. The following can be attributed to the disadvantages of the photometer:

[0031] • the system does not contain photofilters that allow only the fluorescence spectrum to pass through;

[0032] • the specified device does not measure the optical density of the suspension, its temperature and does not ensure the consistency of the obtained data;

[0033] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0034] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0035] • high cost of the photometer, due to the fact that the mechanical switch of light fluxes is not a serial device, and its individual production does not allow to provide the same technical characteristics. A spectrophotofluorimetric detector is known (patent for the Russian Federation utility model No. 77680, published on October 27, 2008), containing a source of ultraviolet radiation, a monochromator with input and output slits of constant cross-section and an optical system, in the center of which a diffraction grating with the possibility of rotation is installed, a mirror lens, photoelectron multipliers, characterized in that it contains a replaceable cuvette for the fluorimetric method of measuring the qualitative composition of a substance, made of three translucent parts, rigidly fastened together with a narrowed hole in the middle translucent part with a diameter of 0.8 mm and a length of 3 mm, and for the spectrophotometric method of measuring the qualitative composition of a substance and an additional photoelectron multiplier.The following can be considered as disadvantages of the detector:

[0036] • due to the low luminosity of fluorescent cells, fluorescence will be observed only at a point located on the axis of the optical system immediately after the wall of the cuvette;

[0037] • the optical scheme used in the detector does not allow recording fluorescent radiation at maximum power, which reduces the accuracy of measurements;

[0038] • the specified device does not measure the optical density of the suspension, its temperature and does not ensure the consistency of the obtained data;

[0039] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0040] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0041] • high cost of the detector due to its complex optical design and the presence of precision mechanisms.

[0042] A spectrophotometer is known (RU Patent for Utility Model No. 147783, published on 20.11.2014) containing a light source in the form of a laser with distributed feedback, lenses, mirrors, cuvettes with the test and reference samples, condensers, a rotating device in the form of a bending piezoelectric plate, polarization attenuators, photocells, a two-channel amplifier, a sawtooth pulse generator, an analog-to-digital converter, a computer, a digital-to-analog converter, characterized in that the spectrophotometer is additionally equipped with an electronic switch, a photocell and a beam-splitting mirror by means of which part of the pump radiation is fed to the photocell, the signal from which is fed to the sawtooth pulse generator, and the electronic switch is connected to the photocell via a computer. The device is intended to determine the optical density, transmittance, fluorescence, scattering, concentration of ingredients of sample samples of different physical states.The disadvantages of the device include the following:

[0043] • complexity of measurements due to the need for reference solutions;

[0044] • the use of sawtooth pulses to illuminate the environment under study does not allow recording the intensity of fluorescence at the moment of saturation of chlorophyll molecules with energy;

[0045] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0046] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0047] • high cost of the device due to the presence of precision mechanisms.

[0048] A portable fluorometer / turbidimeter Aqua Fluor by Turner Designs is known (see http: / / docs.turnerdesiQns.com / t2 / doc / manuals / 998-0851.pdf, https: / / www.turnerdesiqns.com / aquafluor-handheld-fluorometer), which allows measuring fluorescence and optical density of a single sample. The device can be configured with any combination of two channels: in vivo chlorophyll, extracted chlorophyll, cyanobacteria (phycocyanin or phycoerythrin), turbidity, rhodamine BT, fluorescein, ammonium, colored or fluorescent dissolved organic matter, optical brighteners or oil. The disadvantages of the device include the following:

[0049] • the use of a 12-bit analog-to-digital converter reduces the accuracy of determining the fluorescence intensity;

[0050] • the device does not have an interface for transmitting information to an external system;

[0051] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0052] • a device for measuring fluorescence and optical density requires changing optical modules; simultaneous and automated registration of these values ​​is impossible;

[0053] • there are no special elements (parts) for shielding from external electromagnetic fields.

[0054] A high-speed spectroradiometry module based on the AvaSpec-2048-USB2 fiber-optic high-speed spectrometer is known (see https: / / www.avantes.ru / articles / up1 / 22.php), which can be used as a spectrophotometer, photocolorimeter, radiometer, nephelometer or turbidimeter, fluorimeter, fluoroscan or luminometer for analytical studies in the spectral range of 200-1150 nm with very high sensitivity. The disadvantages of this device are:

[0055] • the use of such complex and expensive elements as a diffraction grating, a CCD matrix and a spectrometer does not create the prerequisites for a low cost of the device;

[0056] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0057] • despite the possibility of invasive measurements, the device itself does not have dust and moisture protection, which is necessary for placement in an industrial area, next to capacitive equipment;

[0058] • there are no special elements (parts) for shielding from external electromagnetic fields;

[0059] • the specified device does not measure the temperature of the suspension, which does not ensure the consistency of the obtained data.

[0060] The AquaPen-C AP 110-C fluorimeter is known (see httDs: / / biopik.ru / market / oborudovanie1 / fluorimetry / Dsi photon systems instruments fluorime try / pribor aguapen ap110 c psi / , https: / / handheld.psi.cz / documents / AguaPen Manual- verze 02 2021.pdf) for working with suspensions of photosynthetic biological objects in field and laboratory conditions. AquaPen-C is optimized for measuring the chlorophyll fluorescence of green algae and cyanobacteria. The sensitivity of AquaPen is 500 ng chl / l and allows measurements in natural waters. AquaPen-C has a built-in dual-wavelength LED turbidimeter (720 nm / 680 nm), allowing you to characterize the state of the suspensions under study. The disadvantages of the fluorimeter include the following:

[0061] • the device does not measure the temperature of the suspension;

[0062] • fluorescence measurements are possible in the absence of external illumination of the suspension - to carry out measurements it is necessary to interrupt the cultivation process;

[0063] • the device measures fluorescence in a closed, darkened compartment; measurements under conditions of intense external illumination and especially when immersed in liquid are not provided;

[0064] • low measurement accuracy due to weak fixation of the cuvette. The closest device to the claimed device is a device for measuring the optical parameters of fluorescence intensity, optical density and refractive index in a test sample (patent application No. US20100182606A1, Apparatus and method for multi-parameter optical measurements, published on July 22, 2010), comprising: a) a housing with a detection area for receiving a test sample or a cuvette containing a test sample; b) one or more temperature sensors capable of measuring the temperature of one or more housings, detection areas, test samples or cuvettes; c) one or more temperature controllers for regulating the temperature of one or more housings, detection areas, test samples or cuvettes in the desired range; d) a probing light source in optical communication with the detection area for directing probing light onto the test sample;e) one or more sensors for detecting emitted light of the test sample and for converting the detected emitted light into an output signal; and f) a control system in operative communication with the probing light source, one or more temperature sensors, temperature controllers and one or more sensors, wherein the control system is configured to convert the output signal from the one or more sensors into representative output data of the refractive index of the test sample. The control system is electrically connected to the analyzer for transmitting temperature information for analysis. The disadvantages of the device include the following:;

[0065] • due to the low luminosity of fluorescent cells, it will be observed only at a point located on the axis of the optical system immediately after the wall of the cuvette. And the use of optical schemes indicated in Fig. 3, 4, 6A, 6B, 6C and 7 does not allow recording fluorescent radiation with maximum power, which reduces the accuracy of measurements;

[0066] • the described design does not allow for the creation of complete light saturation of photosynthesis processes due to the insufficiently high power density of light radiation, and, as a consequence, there is no possibility of assessing the efficiency of photosynthesis processes in an illuminated photobioreactor;

[0067] • there are no special elements (parts) for shielding from external electromagnetic fields.

[0068] In addition, the common disadvantages for industrial application of most of the above analogs is the need for manual sampling, which makes it impossible to continuously measure parameters. Also, the appearance of a time gap between sampling and parameter measurement reduces the reliability of the data - the biological environments in the photobioreactor and cuvette change at different rates. This is especially important for large-volume cultivation units, in which the suspension parameters in different parts will not be the same.

[0069] The objective of the present invention is to create a combined device that combines the capabilities of a fluorimeter, turbidimeter and thermometer, creating conditions for continuous automatic multiparameter monitoring of the physicochemical characteristics of suspensions of phototrophic microorganisms cultivated in a specialized device (photobioreactor) in an industrial manner.

[0070] The technical result, which the claimed invention is aimed at achieving, consists in automating the measurement process, increasing the accuracy of measurements and the reliability of the obtained data while simultaneously reducing the cost of manufacturing the device.

[0071] The technical result is achieved by a combined device for measuring the parameters of a suspension of phototrophic microorganisms from inside a photobioreactor, consisting of a housing, inside which are located: a temperature sensor, an emitter directing radiation to the measured medium, a fluorimeter photodetector, a turbidimeter photodetector and an electronic control unit connected to an external information system and a power source, containing an analog-to-digital converter and a signal amplifier connected via communication channels to the emitter, the fluorimeter photodetector and the turbidimeter photodetector. The housing is made hermetically sealed and has a U-shape, the vertical parts of which form a groove intended for moving the measured medium inside it. Parallel walls of the groove contain openings in which sealing glasses are installed on one optical axis.Inside one vertical part of the housing there is a frame of optical devices consisting of two parts, in one part of which the mentioned photodetector of the fluorimeter is installed, and in the other part the mentioned emitter is installed so that the conjugation of the optical axes of the emitter and the photodetector of the fluorimeter is ensured at the boundary of the sealing glass and the measured medium. In front of the photodetector of the fluorimeter and the emitter there are light filters that transmit only radiation of the chlorophyll fluorescence spectrum. The photodetector of the turbidimeter is placed inside the other vertical part of the housing on the same optical axis with the sealing glasses and the emitter. The electronic unit and the temperature sensor are placed in the horizontal part of the housing. At least one mounting bracket is installed on the outer walls of the housing.

[0072] The frame of the optical devices can be designed with the possibility of adjusting the angle of conjugation of the optical axes of the photodetector of the fluorimeter and the emitter.

[0073] One of the outer U-shaped parts of the case can be made in the form of a cover, the edges of which are covered with a sealing gasket along the perimeter. The electronic unit can be connected to an external information system via a sealed cable connector.

[0074] The bit depth of the analog-to-digital converter of the electronic unit can be more than twelve.

[0075] The claimed invention is explained by an illustration, which shows a schematic arrangement of the elements of the combined device inside the housing. The following is indicated by numbers:

[0076] 1 — device body;

[0077] 2 — groove;

[0078] 3, 4 - sealing glasses;

[0079] 5 — frame of optical instruments;

[0080] 6 — emitter;

[0081] 7 — emitter light filter;

[0082] 8 — fluorimeter photodetector;

[0083] 9 — light filter of the photodetector of the fluorimeter;

[0084] 10 — turbidimeter photodetector;

[0085] 11 - screw connections;

[0086] 12 — electronic unit of the device;

[0087] 13 — temperature sensor;

[0088] 14 - sealed cable connector;

[0089] 15 - mounting brackets.

[0090] The combined device consists of a U-shaped housing 1 with a lid (not shown in the figure), the edges of which are covered along the perimeter with a sealing gasket, ensuring the tightness of the internal volume of the housing 1. The vertical parts of the housing form a groove 2 between themselves, inside which the measured medium - the photobioreactor suspension - moves. Inside the walls of the housing 1, which are parallel to the walls of the groove 2, there are openings in which sealing glasses 3 and 4 are installed. All optical elements of the device are located inside the vertical parts of the housing 1. Inside one vertical part there is a frame of optical elements 5, consisting of two parts, one of which contains: emitter 6 and emitter light filter 7, and in the other - a fluorimeter photodetector 8 and a fluorimeter photodetector light filter 9.The emitter 6 is located in close proximity to the photodetector of the fluorimeter 8 so that the radiation of the spectrum inducing fluorescence, created by the emitter 6 for the rapid saturation of chlorophyll molecules, does not fall on the photodetector of the fluorimeter 8. The light filter of the emitter 7 is placed after the emitter 6, and the light filter of the photodetector of the fluorimeter 9 is placed in front of the photodetector of the fluorimeter 8, relative to their optical axes in the direction of the sealing glass 3. In the other vertical part of the housing 1 opposite the sealing glass 4, the photodetector of the turbidimeter 10 is placed and fixed.Optical elements 6-9 are secured inside the frame of optical elements 5 by means of screw connections 11, providing the possibility of adjusting the location and direction of the optical axes of the emitter 6 and the photodetector of the fluorimeter 8 so that their optical axes intersect at a point located immediately after the sealing glass 3 (at the boundary of the sealing glass 3 and the measured medium), and the emitter 6 and the photodetector of the turbidimeter 10 are on the same optical axis. An electronic unit 12 is located inside the horizontal part of the housing 1. The electronic unit 12 consists of a temperature sensor 13, an analog-to-digital converter, a signal amplifier connected via communication channels to the emitter 6, the photodetector of the fluorimeter 8 and the photodetector of the turbidimeter 10. The capacity of the analog-to-digital converter of the electronic unit 12 is more than twelve (for example, sixteen) in order to increase the accuracy of determining the fluorescence intensity.The turbidimeter photodetector 10, the fluorimeter photodetector 8, the emitter 6 and the temperature sensor 13 are connected to the electronic unit 12 via communication channels. The lines that connect the turbidimeter photodetector 10 and the fluorimeter photodetector 8 with the electronic unit 12 must be protected from external electromagnetic fields, since the signals they generate have a low level of electrical voltage. In addition, the power supply lines of the signal amplifiers must also be protected. Such protection is ensured by the location of the device inside the suspension volume, so shielding of the electronic components of the device is not required. The housing 1, in addition to the tightness of the internal volume, ensures a fixed position of the parts of the device located inside it. The device is connected to the external information system using a sealed cable connector 14.Mounting brackets 15 are installed on the outer surface of the walls of the housing 1 for fixing the device on the inner wall of the photobioreactor or any other device cultivating the biological medium. The most preferred number of mounting brackets 15 for reliable fixation of the combined device is 2.

[0091] The operation of the combined device is carried out as follows. Before carrying out measurements of the parameters of the suspension, the device is prepared for operation: open the cover of the housing 1, set the required location of the optical elements 6-9 and the direction of the optical axes of the emitter 6 and the photodetector of the fluorimeter 8 using screw connections 11, and close the cover of the housing 1 back. Based on a signal from the external information system to request the parameter of the optical density of the suspension, the electronic unit 12 forms a series of pulses (consisting of at least one pulse) of rectangular electric current, supplied to the emitter 6. The emitter 6 creates light radiation of the required intensity and duration. The light filter of the emitter 7 provides a given width of the spectrum of radiation of the emitter 6.The radiation, passing through the sealing glasses 3, 4 and the layer of suspension moving between them through the groove 2, is weakened and captured by the photodetector of the turbidimeter 10, which creates an electric voltage signal fed to the input of the electronic unit 12. The electric voltage created by the photodetector of the turbidimeter 10 depends on the intensity of the received radiation, which in turn depends on the optical density of the suspension. The electronic unit 9, having received the signal from the photodetector of the turbidimeter 10, amplifies and digitizes it. After processing the received signal, the electronic unit 12 transmits the received value to the information system. Based on the signal from the external information system for a request for the fluorescence intensity parameter of the microorganism cells, the electronic unit 12 forms a series of pulses (consisting of at least one pulse) of rectangular electric current fed to the emitter 6.Emitter 6 creates light radiation of the required intensity and duration. Emitter light filter 7 provides a given width of the emitter 6 radiation spectrum. The generated radiation is applied to the cells of microorganisms moving through groove 2, next to sealing glass 3 and is absorbed by chlorophyll molecules located in them, transferring them to an excited state. When chlorophyll molecules return from an excited state to the ground state, molecule glow (i.e. fluorescence) occurs, which passes through sealing glass 3 and the light filter of fluorimeter photodetector 9, falling on fluorimeter photodetector 8. The light filter of fluorimeter photodetector 9 ensures the passage of radiation only with a spectrum characteristic of the chlorophyll molecule fluorescence spectrum. The photodetector of the fluorimeter 8 detects the glow of the chlorophyll molecules of the cells of the suspension and generates an electrical voltage signal transmitted to the input of the electronic unit 12.Electronic unit 12 amplifies the signal received from the photodetector of fluorimeter 8 and digitizes it. During irradiation with high-intensity light, conditions for complete light saturation of the primary reactions of photosynthesis are temporarily created in the chloroplasts of algae cells, as a result of which the fluorescence intensity from the beginning of irradiation increases up to 2-3 times and within one millisecond reaches a stationary value (the phenomenon of fluorescence induction, well known and used by specialists in photosynthesis). Measurements of the fluorescence intensity are made at the beginning and end of each light pulse of the entire series. After processing the received signals, electronic unit 12 transmits the value of the ratio of the average fluorescence intensity at the beginning to the average fluorescence intensity at the end of the light pulse of the entire series of pulses created by emitter 6 to the information system.Based on a signal from an external information system to request a suspension parameter, the electronic unit 12 digitizes the signal received from the temperature sensor 13 and transmits the received value to the information system.

[0092] The claimed device allows:

[0093] • perform continuous multiparameter monitoring of the physical and chemical characteristics of biological suspensions (microorganisms and culture fluid) cultivated in a specialized device (photobioreactor) in an industrial manner;

[0094] • ensure consistency of the obtained data when the measured parameters relate to the same volume of suspension;

[0095] • eliminate measurement errors associated with different rates of change in the state of the suspension located inside the culturing device (photobioreactor) and inside the cuvette of the external research device;

[0096] • eliminate manual labor of qualified personnel when measuring the physical and chemical characteristics of biological suspensions - automate the measurement process;

[0097] • produce the device at lower costs by eliminating duplication of identical electronic elements of different devices, such as: controller, analog-to-digital converter, emitter, voltage converter (power supply for electronic components), interface unit with an external electronic system, and by eliminating shielding parts;

[0098] • adequately assess the efficiency of photosynthesis processes (an indicator of the physiological state of cells for controlling the cultivation process) directly in an illuminated photobioreactor. The presence of this capability is fundamental, since the results of measuring chlorophyll fluorescence in living cells are highly dependent on temperature and lighting conditions, and these conditions themselves change quite quickly in a growing culture of microorganisms. Outside the photobioreactor, it is impossible to accurately reproduce the temperature and established light conditions in a selected sample of microorganisms, i.e. the spectrum of light and its intensity, as well as the continuous movement of cells between strongly and weakly illuminated zones;

[0099] • ensure high measurement accuracy due to:

[0100] • limitations of the emitter radiation spectrum;

[0101] • limitations of the radiation spectrum falling on the photodetector of the fluorimeter;

[0102] • excitation of chlorophyll molecules with high-intensity light to increase fluorescence intensity;

[0103] • processing of pulse train signals; • use of a 16-bit analog-to-digital converter to increase the overload capacity of the fluorimeter and photometer under conditions of high algae cell content and constant light irradiation inside the photobioreactor and maintaining sufficient resolution at low microalgae cell content;

[0104] • use of synchronous signal detection, which allows filtering out electromagnetic and light interference in the low-frequency range (from constant over time to frequencies of several hundred hertz);

[0105] • absence of electromagnetic interference in the circuits of photodetectors and their signal amplifiers.

Claims

CLAUSES OF THE INVENTION 1. A combined device for measuring the parameters of a suspension of phototrophic microorganisms from inside a photobioreactor, consisting of a housing, inside which are located: a temperature sensor, an emitter directing radiation onto the measured medium, a fluorimeter photodetector, a turbidimeter photodetector and an electronic control unit connected to an external information system and a power source, containing an analog-to-digital converter and a signal amplifier connected via communication channels to the emitter, the fluorimeter photodetector and the turbidimeter photodetector, characterized in that the housing is made sealed and has a U-shape, the vertical parts of which form a groove for moving the measured medium inside it, the parallel walls of the groove contain openings in which sealing glasses are installed on one optical axis, inside one vertical part of the housing there is a frame of optical instruments consisting of two parts,in one part of which the said photodetector of the fluorimeter is installed, and in the other part the said emitter is installed in such a way that the optical axes of the emitter and the photodetector of the fluorimeter are coupled at the boundary of the sealing glass and the measured medium; light filters are installed in front of the photodetector of the fluorimeter and the emitter, which transmit radiation of only the chlorophyll fluorescence spectrum; the photodetector of the turbidimeter is placed inside the other vertical part of the housing on the same optical axis with the sealing glasses and the emitter; the electronic unit and the temperature sensor are placed in the horizontal part of the housing; at least one mounting bracket is installed on the outer walls of the housing.

2. A combined device according to paragraph 1, characterized in that the frame of the optical devices is designed with the possibility of adjusting the angle of conjugation of the optical axes of the photodetector of the fluorimeter and the emitter.

3. A combination device according to paragraph 1, characterized in that one of the outer Fl-shaped parts of the housing is made in the form of a cover, the edges of which are covered along the perimeter with a sealing gasket.

4. A combined device according to paragraph 1, characterized in that the electronic unit is connected to an external information system via a sealed cable connector.

5. A combined device according to paragraph 1, characterized in that the capacity of the analog-to-digital converter of the electronic unit is more than twelve.

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