全闭合循环的新型微藻基生物沼气工艺的应用基础研究

A full closed-loop of alage-based biogas bio-chemical process was proposed by us and proved useful by some experiments last year. In this study, based on the related theory of chemical engineering and microbiology, some interesting works will be furthered from the multiple perspectives to understand how the new bio-chemical process runs. Denaturing Gradient Gel Electrophoresis (DGGE), and Fluorescence In Situ Hybridization (FISH) can be used in situ to determine the structures of microbial communities under four different micro-ecological environments. According to the knowledge of reaction energetics, a microbial stoichiometry can be easily constructed to explore the relationship to materials that the cells consume and produce. At the same time, free energy and reaction hot can be calculated out for outlining microscopic and macroscopic energy flow distribution on the closed-loop process. Analysis of O2 and CO2 mass transfer in liquid phase and their metabolic rate of microbial populations can give valuable insights into the coupling relationship between microalgae and aerobic bacteria. The above results will help us reduce operating costs and environmental impacts, and improve the efficiency of energy output when the bio-chemical process is put into practices.

针对我们提出的一种全闭合循环的新型微藻基生物沼气工艺，在已展开的工程层面的实验研究基础上，根据化学工程学和微生物学的相关理论，从微生物种群结构、营养物质循环和能源流动分布等多个视角，采用DGGE、FISH和电极电位等原位测试技术以及半反应方法和自由能分析等理论推导方法，从机理层面剖析全闭合循环方式对整个工艺过程的内在影响机理，探讨微生态环境变换下的种群结构及其变化规律，揭示反硝化反硫化和营养元素利用机理，勾画微生物反应的微观和宏观能量流动分配图像，阐明好氧菌群与微藻种群之间的互生耦合机制，为减少工程应用的运行成本、降低环境影响和提高能量输出效率提供全面可靠的理论支持。

针对第三代生物质能源，我们提出了一种全闭合循环的新型微藻基生物沼气工艺，在初步工程研究上开展了基础性研究。从全生命周期的视角，分析了新型微藻闭合沼气工艺的环境影响、经济效益和社会表现，通过对微藻和好氧菌之间的共生关系，提出了进一步改进的方法。采用“火用”理论，比较了微藻工艺和光伏技术、传统沼气工艺的太阳能利用和转化效率，分析了微藻培养、脱氧、厌氧和好氧循环工艺的每一步骤和机理，评价了微藻闭合工艺的理论潜力。探讨了培养过程中微生物群落之间的关系，讨论了微藻中维生素B12、B1、B7营养缺陷的发生情况及其从外部来源如异养细菌中获得维生素的方法，梳理了菌藻相互关系脉胳，为互利共生的工程应用提供理论支持。以小球藻(FACHB-8)、栅藻(FACHB-1297)和铜绿微囊藻(FACHB-905)对研究对象，通过RSM方法，优化了微藻的培养基及培养条件，探讨了各类微藻的代谢途径和自身的化学组成的响应关系，分析了碳氮平衡等环境条件对微藻生物量增长及脂含量的影响规律，为工程化应用提供了重要的科学支撑。