以木质纤维素高固酶解发酵为例，高固形物及其复杂的理化性质会导致体系出现“固体效应”和“水束缚效应”，形成传质速度较低的固液气和微生物复杂多相体系，影响木质纤维素生物转化速率；同时，固形物增加及由此产生的高固酶解发酵流变学特性使以剪切力为主导的机械搅拌在高固多相体系下具有不适应性(会导致酶或微生物活性降低)，从而对搅拌方式、反应器及过程设计放大等提出新的要求. 本工作基于课题组多年的研究，提出高固多相生物反应工程的理念，从固体基质特性入手剖析影响高固多相生物反应速率的关键因素，提出了以周期法向力为动力源的过程强化方法，开发出周期蠕动高固多相生物反应系统，以期为高固多相生物反应工程研究提供理论和技术支持.
Low solid loading bio-reaction system lead to high energy and water consumption, as well as environment pollution in fermentation industries, ing the development of high-solid bio-reaction system. High-solid bio-reaction system has the advantages of low energy consumption, less used water and environmentally-friendly. Additionally, high-solid loading leads to higher concentration of substrate and products which are benefit to reduce cost and realize the economical efficiency in production. However, many difficulties have existed in high-solid bio-reaction system apart form so many advantages. Therefore, it is of great mean to get knowledge about the characteristics and problem of high-solid bio-reaction system which will help to make the most use of its advantages. Taking enzymatic hydrolysis and fermentation of lignocellulose for an example, increasing solid loading leads to ‘solid effects’ and ‘water constraint’. Those phenomenon result in the formation of complex multi-phase system consisted by solid, liquid, gas and the microorganism. Mass transfer performance in this high-solid and multi-phases system is deficient, thus affecting lignocellulose conversion performance. Additionally, the changes of rheology characteristics in high-solid and multi-phases bio-reaction system caused by increasing solid loading make it inappropriate to apply traditional mechanical agitation which is based on shear force (i.e. shear force can results in activity loss of the enzyme and microorganism) to high-solid and multi-phases bio-reaction system, putting new requirements on agitation methods, design and amplification of bioreactor and process of high-solid and bio-reaction system. Based on several-years studies, the conception of high-solid and multi-phases bio-reaction engineering was proposed. Key factors which affect the reaction performance were analyzed from the perspective of solid matrix characteristic. Intensification method based on periodical normal force is innovated and periodic peristalsis high-solid and multi-phases bio-reaction system was developed with the expectation of providing theory and technical support for studying high-solid and multi-phases bio-reaction engineering.
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