秸秆厌氧消化抑制诊断体系构建及复合调节剂多元调控机理研究

Anaerobic digestion is a complicatedly biological metabolic process with collaborative involvement from multi-population microorganism, its operation evaluation, warning feedback and regulation has become a hot topic. For straw biomass, there are some problems in the anaerobic digestion process, such as low degradation efficiency, slow reaction rate, easy acidification, even more lack of comprehensive evaluation index system and effective regulation measures. In this project, based on constructing process stability evaluation and inhibition diagnosis system, a multi-scale straw anaerobic digestion inhibition diagnosis network diagram coupling with materials, microorganisms and metabolic product will be built. The effect weight, inhibition threshold and stress response relationship can be achieved. The nutrient and clay mineral materials will be combined into composite regulators. To explore the cooperative mechanism of composite regulators, the material and energy metabolism, microorganism and enzyme activity, as well as regulation effect of the complicated anaerobic digestion process will be analyzed. The gas production kinetics model based on carbon transition mechanism will also be studied to discover the relationship between the composite regulators and the material conversion and methane production rate. The enhancing regulation strategy and optimal operating efficiency will be obtained. The project will be beneficial for efficient regulation of anaerobic digestion process and achieving the high-value utilization of straw biomass.

厌氧消化过程是由多种群微生物协同参与的复杂生物代谢过程，其运行评估、预警反馈与调控已成为研究热点。针对秸秆类原料厌氧消化降解效率低，速率慢，易产生酸化产物积累，且缺乏全面的运行评价指标体系和有效的调控手段等关键问题，本项目以构建秸秆厌氧消化过程失稳预警评估和抑制诊断体系为前提，建立原料、微生物、代谢中间产物相互偶联的多尺度秸秆厌氧消化抑制诊断网络图，确定抑制影响权重、抑制阈值和应激响应关系。将营养物质和粘土矿物材料优化配置为复合调节剂，强化过程调控，从刺激发酵、解除抑制、提高微生物和酶活性、促进物能转化等多角度，全面系统地揭示复合调节剂的多元调控效应和协同调控机理。通过基于碳素转移机理的厌氧消化产气动力学模型建立复合调节剂与原料转化和产甲烷之间的定量关系，获得最佳调控策略和运行效率。研究工作对提高秸秆类原料厌氧消化效率和稳定性具有重要科学参考和实际价值。

厌氧消化过程是由多种群微生物协同参与的复杂生物代谢过程，其运行评估、预警反馈与调控已成为研究热点。针对秸秆类原料厌氧消化降解效率低，速率慢，易产生酸化产物积累，且缺乏全面的运行评价指标体系和有效的调控手段等关键问题，本项目重点开展了秸秆厌氧消化过程不同运行条件下的预警体系构建、预警指标筛选与阈值确定研究；单一、复合调节剂对秸秆及其他拓展原料厌氧消化过程的影响效果及作用机理研究，并构建修正的BioMode动力学模型，对不同运行条件下的秸秆厌氧消化过程进行了拟合，为秸秆厌氧消化过程调控、预测提供了理论方法和基础数据。通过三年的基础研究，获得以下主要结论：（1）在厌氧消化过程中，有效的监控及预警是必不可少的。综合考虑指标的灵敏性、稳定性和测试性能，IA/BA和总VFA被筛选为秸秆厌氧消化系统的最佳预警指标。IA，BA和VFA/BA被筛选作为辅助预警指标。（2）修正的Biomodel模型与实际试验数据拟合良好，可用于模拟并预测秸秆厌氧消化过程，并在筛选预警指标中发挥了关键作用，这表明计算机建模用以监测厌氧系统变化及提高沼气工程运行标准的可能性。（3）富氮调节剂和矿物材料调节剂对于厌氧消化过程可起到调节物料营养比例降低酸化风险、提高微生物活性及影响优势种群分布等作用，有利于厌氧消化效率的提高。研究结果对提高秸秆类原料厌氧消化效率和稳定性具有重要科学参考和实际价值，并对厌氧消化过程监控、预测与模拟提供有效的方法和技术支撑。