【作者】 唐萍；

【导师】 苏义脑； 郑津洋； 杨健；

【作者基本信息】 浙江大学 ， 化工过程机械， 2011， 博士

【摘要】 随着资源、能源、环境和安全等问题的日益突出,在石化、医药、轻工和食品加工等生产过程中,由产出、能耗、排放和安全等构成的体系及优化越来越值得深入研究。如何在高效、高品质产出同时,实现“节能、减排、安全和绿色生产”是国内外正在积极开展的重要研究课题,并且成为我国中长期科技发展规划中的重点攻关内容。而在上述化工过程中,反应与分离是最常见也是至为关键的环节,将二者集成与控制是实现高效生产和节能减排的最有效手段。因此,本论文提出了一种基于可控反应器与可连续色谱分离集成的新装备技术,其通过将多个平行反应单元与分离单元进行耦合控制,可以在最高的反应转化率和最佳的分离效果之间找到最优点。将其成功应用于壳寡糖和甘露醇等资源产品的制备中,可以在处理能力、生产效率、节能指标、溶剂消耗和产品质量等多方面进行综合优化,带来颇为理想的产能效果和广阔的应用前景。本文的主要研究内容及创新在于：(1)在深入进行连续色谱分离和可控电化学反应机理研究之上,自主提出了基于耦合型模拟移动床技术(Coupled/Cascade Simulated Moving Bed,简称CSMB)的集成反应分离系统设计与耦合控制方法。主要是,对于多个不同功能的并行单元组成,通过电磁阀组合设计与程控切换,使多个反应器与层析柱间实现串、并联,进而构成具有因果关联的功能区块；针对不同的产品要求,采用自主提出的流程与控制算法,实现了区域式模拟移动床和多元分流式二种新型分离体系；通过系统的连续一体化、周而复始运行,可以在最好的反应转化率与最佳的分离点之间寻求平衡,实现反应分离耦合和系统集成优化；将其工作状态调整到最优点后,就可以在高效率、高精度和高品质制备同时,有效地降低能耗,减少有机溶剂排放,实现多组分连续反应提取和机电一体化生产。(2)基于层析柱理论模型和化学反应的过程传质原理,建立了可控反应器与可连续色谱分离集成的过程数学模型和模拟方法。主要是,在确定色谱分离与反应传质过程的模型参数之上,建立了反应分离集成中的单柱分离、双柱串联、多柱串并联和多组分分离操作等基本过程模型,并各自进行了FEMLAB建模求解；结合工艺试验,在验证求解结果同时,获得了切换控制的时间点；建立了反应分离耦合的一体化模型,获得了找出最优反应分离耦合点的方法；另外,针对反应与分离耦合中的关键因素,分别探讨了柱长、流速和进样量等的实际影响,给出了其作用规律和优化措施。(3)基于以上设计思路、建模分析和关键工艺试验等,自主开发出一套具有通用性和可拓性的集成反应分离装备。主要包括,自主设计并加工出一套反应可控的新颖电化学反应器,其通过实时电导、电流和pH等检测,可以感知与控制反应进程；针对多组份分离的流动控制要求,自主搭建出一套可连续色谱分离的多层析柱串、并联系统,其通过不同的电磁阀组合切换,可以分别实现区域式模拟移动床和多元分流式连续分离操作；最后,采用程控恒流泵输送,由IPC-PLC组成上下位机控制系统,采用MCGS进行软件组态,由折射仪、生物传感分析仪和HPLC等进行产品检测,将上述单元组装成为一套CSMB耦合模拟移动床集成反应分离装备。(4)在此CSMB集成反应分离装备平台上,采用自主提出的工艺控制方法,分别进行了甘露醇和壳寡糖制备的试验研究。主要是,采用电化学法还原葡萄糖来制备甘露醇,将其与自主提出的区域式模拟移动床分离进行集成；采用自主提出的电化学法氧化降解壳聚糖来制备壳寡糖,分别与以单柱和双柱串联为基本分离单元的两种多元分流式连续分离进行集成；以上均获得了最佳的工艺路线和高品质目标产物,并且对过程节能和排放进行了量化分析。上述试验结果证实,对于多组分混合产物,集成反应分离方法是高效率获取高纯度产品的有效途径,其连续高效的一体化生产能大大节省能源,极大地减少有机溶剂对环境的污染,其研发紧扣当前“高效生产”、“绿色化工”和“节能减排”等重要发展方向,颇具推广应用价值。更多还原

【Abstract】 With the resources, energy, environment and security issues becoming more prominent, the system consisting of production, energy consumption, emissions and safety and its optimization is becoming increasingly important in the petrochemical, pharmaceutical, light industry and food processing, production process. How to ensure efficient high quality output, and to achieve "energy saving, emission reduction, safety and green production" have become an important research topic, and focus research content in long-term technology development plan in china. In the above chemical process, reaction and separation are the most common and key parts. The integration and control of the reaction and separation is the most effective mean to achieve both efficient production and energy savings. In this paper, the CSMB, coupled/cascade simulated moving bed reaction-separation integrated technology was proposed. Through the integrated control of the multiple separation units and reaction units, the optimal point between the highest conversion rate and the best separation performance was found. This technology was successfully applied to the research products of oligosaccharide, mannitol and other resources. The multi-component separation and continuous integration production was achieved. The resulting products have been optimized in processing power, energy efficiency indicators, productivity, solvent consumption, product performance and other aspects. The targets of a fine resource extraction, waste regeneration, green processing and optimization of energy efficiency and emission reduction were achieved. The main research content and innovations are:(1) Based on study of continuous chromatographic separation and principle of controlled electrochemical reaction, the novel CSMB coupled/cascade simulated moving bed reaction-separation integrated technology was proposed, which was constituted by different functional units. The separation unit was composed with different blocks formed by series-parallel columns. Through the reasonable control algorithms and the combination design of the valve, the series/parallel of the separation units and reactor units were formed, and then the division of the various functional blocks were achieved. For different product requirements, using the proposed algorithm and control process, the regional-type simulated moving bed separation coupling system and multi-cell reaction-separation integrated system were established. Through the continuous integration cycle run, the balance of the highest conversion rate and the best separation performance was achieved, and the optimized integration of reaction and separation was realized. When the system working in the optimum condition, the high efficiency, high precision and high-quality preparation can be met, at the same time, the energy consumption and organic solvents emissions can be effectively reduced. Then the mechanical and electrical integration production of multi-component can be realized.(2) Based on the basic theory of the chromatographic separation and chemical reaction mass transfer, the chromatographic separation parameters involved in the model were determined. The single column, two series columns, multi-columns in series and multi-fractionation chromatography separation models were established and solved through FEMLAB soft. The modeling solution in good agreement with the experimental results, then the separation control time point were accurately given. Based on the separation model, the reaction-separation coupling model was established, and the optimal coupling point was determined. Column length, flow rate, injection volume and other factors in coupling reaction and separation technology were considered and optimized, and then optimization measures were given.(3) According to the above design ideas, model analysis and key process tests, a versatility and opening reaction separation integrated equipment was exploited. A novel controlled electrochemical reactor was designed and fabricated. Through the real-time conductance, current and pH test, the reaction process can be sensed and controlled. According to the multi-component separation requirements, a separation system of series/parallel multi chromatograic columns was developed, through a different combination of the valve switch, the regional-type simulated moving bed separation coupling system and multi-cell reaction-separation integrated system were realized. Finally, through the transportation of the programmable constant pumping, the control system composed by the 1PC-PLC, the software configured with MCGS, testing by refractometer, bio-sensing analyzer and HPLC, the CSMB integrated equipment coupling reaction and simulated moving bed separation was established.(4) Using the proposed CSMB integrated technology, in the designed reaction-separation integrated platform, the preparation of mannitol and chitosan were researched. In the preparation of mannitol, the mannitol was prepared by electrochemical reduction and integrated with the regional-type simulated moving bed separation coupling method. In the preparation of chitosan, the electrochemical degradation of chitosan were carried out, and two multi-cell reaction-separation integrated methods were used, base on single column and two columns in series as the basic separation unit. The best process route and high-quality objectives were obtained in the above preparation, and process energy and emissions were quantitative analyzed. The results show that, for multi-component mixture, the reaction-separation integrated technology is highly efficient separation method to obtain high purity products. And its continuous and efficient integration of production can greatly save energy and reduce environmental pollution caused by organic solvents, and its R & D closely linked to the current "high production", "green chemistry" and "energy saving" and other important development directions, with a high application value.更多还原