Microbial fermentation system scheme

Microbial fermentation process is a very important production link in the fermentation industry, the article first introduces the research on the environmental control system of fermentation tank in the fermentation processThen a practical scheme to satisfy the computer distribution control system (DCS) in the fermentation production process is introduced, and the design problems of system function and composition at all levels are discussedFinally, it understands a newly developed set of advanced control structure based on industrial Ethernet, the latest embedded system control technology, the monitoring system with complete function, the microbial fermentation monitoring system with advanced control technology and advanced algorithm expansion function, the forewordmicrobial fermentation is a complex biochemical reaction process, in order to improve the yield of the final product, it is necessary to ensure that there is a suitable microbial growth and metabolic environment in the whole operation process, on this basis to optimize the fermentation process controlTherefore, the control of fermentation environment is an extremely important part of fermentation industryWith computer control, it is possible to realize the automatic control of the fermentation process parameters of the online real quantity, recording, graphic display, automatic storage of historical data, report printing and environmental parametersIn recent years, the biotechnology industry has developed rapidly, and biofermentation technology and fermentation device, as the basis of biotechnology industrialization, have attracted wide attentionMicrobial fermentation process, the mechanism is very complex, the influence factors are complex, it is difficult to use the mathematical model to describe, coupled with the lack of on-line detection of fermentation biomass parameters of the sensor, to the biofermentation automation has brought difficulties, so it is necessary to develop an effective monitoring system, body1, microbial fermentation process environmental control systemfermentation process is more complex, involving the growth and metabolism of microbial cells, is a dynamic process with time-change, randomness and variability input and outputBecause some variables (bacterial concentration, matrix concentration, product yield, etc.) are difficult to detect online, can not be directly as the accused variable, so in the fermentation process mainly using quality-related variables, such as temperature, stirring speed, pH, dissolved oxygen, ventilation, foam, etcas the accused variablesIn view of the importance of the various environmental parameters affecting microbial metabolism in fermentation, the key control of temperature pH, dissolved oxygen and foam height is introduced(1) temperature controltemperature control has a optimal growth temperature for specific microorganismsTherefore, the control of fermentation temperature of microbial fermentation process is very important for the microbial growth environment parametersPID control algorithm is the most widely used and technically mature basic control algorithm in industrial engineering, considering its simple structure, easy to adjust parameters, high control accuracy, wide applicability, and the function of no residual differenceSo the temperature control uses this algorithm, and separately constitutes the control loopthe pH value of the(2) PH controlis another important environmental parameter of microbial growthIn the fermentation process, it must be strictly controlled, otherwise it will seriously affect the metabolism of microorganisms and the synthesis of metabolitesBecause the characteristics of the fermentation process pH regulating object is strong, the relationship between the addition of pH regulator and the change of the pH of the fermentation fluid is complex, and near some pH, the pH change is very sensitive to the amount of the added pH regulator, while the sensitivity is significantly reduced near the other pHThe problem can be solved by using the control peristaltic pump's break-in time to adjust the pH in the fermentation fluid(3) dissolved oxygen concentration controlin the process of oxygen-consuming fermentation, oxygen is a necessary raw material for microbial growth, if the lack of oxygen supply, will inhibit the growth and metabolism of microorganisms, for this reason, in the fermentation process, to maintain a certain concentration of dissolved oxygen DOThe main factors affecting dissolved oxygen concentration DO are the amount of air supplied, the speed of the mixing paddle and the pressure of the fermentation tankAt present, the control of dissolved oxygen concentration in domestic fermentation tanks is mainly achieved by adjusting the speed of the mixing pad or regulating the amount of air supplied, and is mostly manual operation, the control accuracy is not highThe DO concentration variable (main parameter) can be used as the charged variable, and the stirring speed (subparameter) can be used as the control means to form a string control system with the main and sub-two circuitsThe actual value of the speed is constantly changed with the change of dissolved oxygen in the fermentation tank, and finally the main parameter is controlled at the given value(4) fluid level and defoaming control in the pre-fermentation period, microbial growth is strong Add the liquid full load, stirring motor full speed start, air flow volume to the maximum, when the fermentation liquid floating very strong, a little careless, may produce the phenomenon of escape At this time, it is necessary to add defoaming agent in time to reduce foam and prevent the fermentation liquid from floating Using the resistance bar as the level detection element, when the fermentation liquid surface reaches a certain height, automatically open the defoamer valve, when the liquid surface drops back to normal, automatically close the defoamer valve In defoaming control, the process is slow to respond, so a time delay should be added to the control loop to prevent the addition of excessive defoamers 2, microbial fermentation microcomputer distribution control system in antibiotics, enzymepreparations, MSG brewing and other fermentation industry, microbial fermentation process is a very important production link, fermentation directly affects the quantity, quality and production costs of products The computer distribution control system not only realizes the online real quantity detection, recording, graphic display, automatic storage of historical data, report printing and automatic control of environmental parameters, but also lays a good foundation for the optimization and control of fermentation industry most people use computer control technology for automatic control of the fermentation process, its structure is basically the use of industrial control machine or PC machine for the upper computer, the next machine is using STD bus or microcontroller, the system is complex and the cost is high Can use the upper and lower machine way to build the system, the lower computer using PLC, the upper computer using ordinary PC The two communicate through the serial port to realize the acquisition and transmission of data first of all, the use of PLC as the lower machine, and designed to automatically select offline (off the upper machine) or the two operating modes, because the PLC is reliable, once the upper machine problems, will not affect the normal operation of the lower machine, in addition, up and down Communication between the bit machines using a dedicated isolation cable, so that can well avoid the impact of the field signal on the computer to protect the computer, PLC itself has the internal and field signal photoelectric isolation design, so it is difficult to string the field strong power into the PLC, so that the system can be reliable for a long time according to the need stomping for the online monitoring of fermentation process and the analysis and management of real-time information, the system has the following functions: (1) can set the number and communication functions: including control parameter setting, indirect parameter calculation and offline parameter input; Receive detection parameters sent from the lower machine in real time (2) detection and control functions: online measurement of the main variables and biomass in the fermentation tank (e.g stirring speed, culture temperature, fermentation liquid pH, dissolved oxygen concentration, etc.) on-line, on-line calculation of indirect parameters such as bacterial concentration, product concentration and matrix concentration, in order to understand the physiological, biochemical characteristics of the culture object in the fermentation process, grasp its growth trend, and provide the experimental basis for optimizing the process control and amplification process (3) screen display function: various real-time parameters, charts, fermentation process dynamic refresh with real-time fermentation process status monitoring flow chart display, to guide the corresponding operation (4) operation management functions: in the computer through the graphical operating interface and multi-layer menu, select a variety of operating functions, including setting limits, setting important control parameters for the lower machine, sampling time settings, display or printing process data (5) information storage and report and curve printing functions: recording and saving the status and data in the process of operation is an important task in the online monitoring of fermentation process Meet the requirements of a variety of analytical statistics with accurate records, as well as operational guidance for future monitoring A general implementation of record saving is to obtain pre-selected data sets at intervals and save them in a database file 3, the monitoring system of microbial fermentation process the monitoring system of the newly developed microbial fermentation process first based on the principle and process of microbial fermentation, the control parameters and control object model, innovatively put forward the index integral PID control and fuzzy PID control algorithm, and obtained good control effect in practical application, and the monitoring software design method of the microbial fermentation process, using LabWindows/CVI development environment to develop a flow chart display, using The lab Windows/CVI development environment Real-time and historical trend chart display, historical data preservation, Excel format report, industrial Ethernet communication, custom advanced algorithm interface and other complete functions of the monitoring software, and finally for the use of Rabbit2000 as an embedded network controller, the design of ARM9 advanced embedded microprocessor and embedded Linux powerful embedded all-in-one machine, and the use of MSP430 microcontroller designed with high interference resistance, Isolated data collectors that can be applied to harsh industrial environments, and then connect multiple data collectors to embedded all-in-ones via RS485 master-slave bus, making the system more scalable industrial control system is moving towards digitalization, intelligence, networking and openness Industrial production needs to be intelligent, digital transformation, automatic control, embedded technology and its products play a vital role Embedded systems are defined as: application-centric, computer-based, software hardware can be cropped, can adapt to the application system on the function, reliability, cost, volume, power consumption of strict requirements of the dedicated computer system Embedded applications have expanded from industry, communications, and networks to consumer areas related to digital multimedia, and their strong momentum validates the prediction of Nigro Ponti, the global advocate of the digital revolution, that embedded applications are the greatest application invention spent after pCs and the Internet the system has designed a control structure with good development, dispersion, easy to expand and integrate with the help of the rapid development of embedded system technology in industrial control And designed intuitive, friendly, easy to operate, compatible with other programs of monitoring software III, conclusion This paper mainly introduces the microbial fermentation process environmental control system of several environmental parameters and how to achieve the automatic control of microbial fermentation through the computer distribution control system Microbial fermentation process is a very important production link in the fermentation industry, the paper introduces the actual scheme of computer distribution control system (DCS), mainly discusses the system function With the rapid development of biotechnology industry, biofermentation technology and fermentation device as the basis of biotechnology industrialization, the control system in the process of microbial fermentation will be more and more finely perfected, and the problems in biofermentation automation will gradually disappear