真菌深层发酵过程溶解氧控制研究
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摘要
微生物发酵是许多行业的一个关键生产过程，真菌又是食品和药物方面最具潜力的发酵微生物种类之一。真菌发酵应用于有用代谢产物的生产具有很多优点，因此必将成为未来获得大量真菌有用代谢物的一种重要方法。溶解氧问题广泛存在于众多学科，对溶解氧进行有效控制有着重要的科学和工程意义，然而到目前为止，微生物发酵过程溶解氧的自动控制问题还没有得到真正解决。工业发酵生产要求对发酵过程进行优化和控制。本论文主要讨论了真菌深层发酵生产γ-亚麻酸的过程中溶解氧的自动控制问题，设计了真菌深层发酵自动控制系统并建立了基于泛布尔代数的溶解氧自动控制模型。全文共分五章。
首先简要介绍了目前微生物发酵过程自动控制的热点研究问题和溶解氧自动控制的研究现状，并对溶解氧相关问题及溶解氧控制问题作了简要说明。
对发酵的过程参数进行在线监测及数据采集是对整个发酵过程进行监控和研究的必备条件。在第二章中，本文对目前微生物发酵过程参数的检测状况进行了全面的介绍，主要包括对发酵过程中溶解氧和其它各参数进行测量的常用方法和仪表，以及发酵过程对这些方法和仪表的特殊要求。
第三章主要围绕微生物深层发酵过程控制系统的设计与实现展开。根据发酵罐的特点，本文基于单片机和PC机结合，设计了发酵过程自动控制系统，实现DO、pH、温度、罐压、通气量和搅拌电机转速的测控以及发酵液的粘度的在线测量。对系统的硬件和软机构成和工作原理以及对各种发酵过程参数的检测和控制方法作了详细说明。
第四章对发酵过程中溶解氧的影响因素作了全面的综述。在分析了大量实验数据的基础上，针对微生物深层发酵过程中非线性、大滞后、时变的溶解氧系统，建立了基于泛布尔代数的逻辑控制模型。此方法根据实验经验和逻辑控制规则，不依赖于被控对象的精确数学模型，避免了常规控制算法建立对象精确数学模型的困难。本文随后设计了该逻辑算法的仿真实验，验证了算法的可行性。结果表明，与传统的控制算法相比，该方法还在稳定性方面具有突出的优点。
最后，对本文所做的工作以及逻辑控制算法进行了简短的总结。
For many industries, fermentation is a fundamental process, and eumycete is one of the most promising fermenting microbes for food and medicine. It is much advantageous to get secondary metabolin by eumycete fermentation, and will be a important way to produce the metabolin. Dissolved Oxygen (DO) is involved in many domains of science, and it has great science and engineering significance to apply control over DO. However, DO control in microbe fermentation process is indeed left unsolved so far. Industrial fermentation requires optimized and controlled condition. This dissertation mainly deals with the control over DO in microbe fermentation process producing y-linolenic, devises a control system and builds up a DO controlling model based on Pan-bool algebra. The whole work consists of five chapters.
Firstly, this paper outlines noticeable researches on microbe fermentation auto control , DO involves and DO control at present.
To fermentation process, to measure and collect the data of the parameters is the premise of the control over them. Chapter 2 argues the present status of parameter measurement in fermentation, including the methods and equipment, and the restrictions fermenter applies to them.
Chapter 3 primarily informs the fermentation process control system devising and the structure of the system. According to the characteristic of fermenter, we designed the control system based on single chip computer and personal computer, realizing the measurement and control over DO, pH, temperature, pressure, ventilating rate and the speed of the stirring motor. The paper details the hardware and software structure, and the working principle of the system, as well as the method to measure and control the parameters.
Chapter 4 discusses the factors influencing DO in the process of fermentation in detail. Analyzing much experiment result, the paper presents a logical controlling method based on Pan-bool algebra and constructs the controlling model in allusion to the non-linear, time-varying, delaying DO control system. This theory depends on experience and logical control laws and needs no accurate mathematic model of the object, so approaches the difficulties traditional control method encounters building accurate model of the object. By simulation, the paper
subsequently shows the feasibility of the method, and the result shows that this method is much advantageous over traditional methods in stability.
Lastly, the work of the dissertation and the logical control method are briefly summarized.
首先简要介绍了目前微生物发酵过程自动控制的热点研究问题和溶解氧自动控制的研究现状，并对溶解氧相关问题及溶解氧控制问题作了简要说明。
对发酵的过程参数进行在线监测及数据采集是对整个发酵过程进行监控和研究的必备条件。在第二章中，本文对目前微生物发酵过程参数的检测状况进行了全面的介绍，主要包括对发酵过程中溶解氧和其它各参数进行测量的常用方法和仪表，以及发酵过程对这些方法和仪表的特殊要求。
第三章主要围绕微生物深层发酵过程控制系统的设计与实现展开。根据发酵罐的特点，本文基于单片机和PC机结合，设计了发酵过程自动控制系统，实现DO、pH、温度、罐压、通气量和搅拌电机转速的测控以及发酵液的粘度的在线测量。对系统的硬件和软机构成和工作原理以及对各种发酵过程参数的检测和控制方法作了详细说明。
第四章对发酵过程中溶解氧的影响因素作了全面的综述。在分析了大量实验数据的基础上，针对微生物深层发酵过程中非线性、大滞后、时变的溶解氧系统，建立了基于泛布尔代数的逻辑控制模型。此方法根据实验经验和逻辑控制规则，不依赖于被控对象的精确数学模型，避免了常规控制算法建立对象精确数学模型的困难。本文随后设计了该逻辑算法的仿真实验，验证了算法的可行性。结果表明，与传统的控制算法相比，该方法还在稳定性方面具有突出的优点。
最后，对本文所做的工作以及逻辑控制算法进行了简短的总结。
For many industries, fermentation is a fundamental process, and eumycete is one of the most promising fermenting microbes for food and medicine. It is much advantageous to get secondary metabolin by eumycete fermentation, and will be a important way to produce the metabolin. Dissolved Oxygen (DO) is involved in many domains of science, and it has great science and engineering significance to apply control over DO. However, DO control in microbe fermentation process is indeed left unsolved so far. Industrial fermentation requires optimized and controlled condition. This dissertation mainly deals with the control over DO in microbe fermentation process producing y-linolenic, devises a control system and builds up a DO controlling model based on Pan-bool algebra. The whole work consists of five chapters.
Firstly, this paper outlines noticeable researches on microbe fermentation auto control , DO involves and DO control at present.
To fermentation process, to measure and collect the data of the parameters is the premise of the control over them. Chapter 2 argues the present status of parameter measurement in fermentation, including the methods and equipment, and the restrictions fermenter applies to them.
Chapter 3 primarily informs the fermentation process control system devising and the structure of the system. According to the characteristic of fermenter, we designed the control system based on single chip computer and personal computer, realizing the measurement and control over DO, pH, temperature, pressure, ventilating rate and the speed of the stirring motor. The paper details the hardware and software structure, and the working principle of the system, as well as the method to measure and control the parameters.
Chapter 4 discusses the factors influencing DO in the process of fermentation in detail. Analyzing much experiment result, the paper presents a logical controlling method based on Pan-bool algebra and constructs the controlling model in allusion to the non-linear, time-varying, delaying DO control system. This theory depends on experience and logical control laws and needs no accurate mathematic model of the object, so approaches the difficulties traditional control method encounters building accurate model of the object. By simulation, the paper
subsequently shows the feasibility of the method, and the result shows that this method is much advantageous over traditional methods in stability.
Lastly, the work of the dissertation and the logical control method are briefly summarized.
引文
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【2】 [日]植村定植郎 相田浩．发酵与微生物．科学出版社．1980
【3】 高孔荣主编．发酵工程与设备．轻工业出版社．1981
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【8】 张嗣良．发酵过程多水平问题及其生物反应器装置技术研究—基于过程参数相关的发酵过程优化与放大技术．中国工程科学．2001．8
【9】 张星元．微生物生物工程的三个基本观点．无锡大学学报．2001．7
【10】 吕太平，陈世光等．光纤氧传感器的研制及对溶解氧的测定．分析化学来稿摘登 2001．2
【11】 张南纶等．一类复杂系统的逻辑分析．系统工程．1995．3(4)
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【13】 任凤莲，周平，吴南．水中溶解氧的测定．广州化学．2002．3
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【18】 邓元修等．生物反应器K_(1a)值测定的模拟稳态法研究．武汉城市建设学院学报 2001．3
【19】 钟辉，张峻，邢来君．微生物发酵法生产γ—亚麻酸的研究进展．微生物学通报．1994．9
【20】 肖春玲．γ—亚麻酸的发酵生产与应用．吉安师专学报(自然科学)．1998．6
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【22】 易美华，刘清燕，周秋华．γ—亚麻酸产生菌及其发酵条件的研究．海南大学学
报自然科学版．1995．12
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【25】庄毅．药用真菌新型(双向型)固体发酵工程．中国食用菌．1985．1
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【27】张平之等．微生物生化工程．中国商业出版社．1995
【28】姜长宏等．溶解氧和尾气CO_2在发酵工业中的作用．沈阳化工学院学报．2000．3
【29】王克荣，李庆春．从酵母菌和香菇看真菌的应用．中学生物教学．1996．2
【30】陈毅坚．真菌分类的变化与发展．玉溪师范高等专科学校学报．2000．16
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【34】Lee, Tae Ho; Chang, Yong Keun; Chung, Bong Hyun; Park, Young Hoon. Correlation of redox potential with state variables in cultures under controlled dissolved oxygen concentration and pH. Biotechnology Progress 【BIOTECHNOL PROG】. vol. 14, no. 6, pp. 959-962, Dec 1998
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【2】 [日]植村定植郎 相田浩．发酵与微生物．科学出版社．1980
【3】 高孔荣主编．发酵工程与设备．轻工业出版社．1981
【4】 潘新民、王燕芳．单片微型计算机实用系统设计．人民邮电出版社．1992
【5】 爱钧、彭秀华．单片机高级语言C51的应用程序设计．电子工业出版社
【6】 王谦．大型食用真菌与发酵工程．广西轻工业．1995．3
【7】 焉平、陈吉．看不见、听不着的食品加工厂．职业技术教育．1999．12
【8】 张嗣良．发酵过程多水平问题及其生物反应器装置技术研究—基于过程参数相关的发酵过程优化与放大技术．中国工程科学．2001．8
【9】 张星元．微生物生物工程的三个基本观点．无锡大学学报．2001．7
【10】 吕太平，陈世光等．光纤氧传感器的研制及对溶解氧的测定．分析化学来稿摘登 2001．2
【11】 张南纶等．一类复杂系统的逻辑分析．系统工程．1995．3(4)
【12】 张南纶，肖蹊安等．泛布尔代数公理体系．中国人民解放军空军气象学院学报．1985．1
【13】 任凤莲，周平，吴南．水中溶解氧的测定．广州化学．2002．3
【14】 赵学明．搅拌生物反应器的结构模型、放大及搅拌器改型．化学反应工程与工艺 1996．3
【15】 杨雄，柳琳，赵九军，刘炯．发酵自动控制技术．计算机应用研究．2001
【16】 汤忠鎏．广义卡尔曼滤波算法在真菌发酵过程状态估计中的应用，信息与控制．1995．8
【17】 姜长洪等．在线分析仪表在发酵工程中的应用．仪表技术与传感器．2000．12
【18】 邓元修等．生物反应器K_(1a)值测定的模拟稳态法研究．武汉城市建设学院学报 2001．3
【19】 钟辉，张峻，邢来君．微生物发酵法生产γ—亚麻酸的研究进展．微生物学通报．1994．9
【20】 肖春玲．γ—亚麻酸的发酵生产与应用．吉安师专学报(自然科学)．1998．6
【21】 杨蕊，陈焕文，张寒琦，于爱民，金钦汉．溶解氧的快速现场测定．高等学校化学学报．2002．8
【22】 易美华，刘清燕，周秋华．γ—亚麻酸产生菌及其发酵条件的研究．海南大学学
报自然科学版．1995．12
【23】戚以政等．生化反应与反应器．化学工业出版社．1999
【24】郁静怡等．代谢工程．生物工程学报．1996．12
【25】庄毅．药用真菌新型(双向型)固体发酵工程．中国食用菌．1985．1
【26】汤亚杰，钟建江．高等真菌深层发酵生产有用生物活性物质．华东理工大学学报．2001．12
【27】张平之等．微生物生化工程．中国商业出版社．1995
【28】姜长宏等．溶解氧和尾气CO_2在发酵工业中的作用．沈阳化工学院学报．2000．3
【29】王克荣，李庆春．从酵母菌和香菇看真菌的应用．中学生物教学．1996．2
【30】陈毅坚．真菌分类的变化与发展．玉溪师范高等专科学校学报．2000．16
【31】ATMEL. AT89C51 8--bit Microcontroller with 4K Bytes Flash
【32】ALOG DEVICES. 3V/5V, CMOS, 500 μA SIGNAL CONDITIONING ADC AD7714
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