混合花卉秸秆厌氧发酵产甲烷特性及动力学研究

为研究混合花卉秸秆厌氧发酵产甲烷特性，选取玫瑰（Rosa rugosa），百合（Lilium lancifolium），满天星（Gypsophila paniculata），向日葵（Helianthus annuus）花卉秸秆混合物与驯化过的猪粪、牛粪混合物进行厌氧发酵试验。设置3种不同的总固体（Total solids，TS）浓度（3%、5%和7%）观察厌氧发酵产甲烷特性及系统稳定性。采用3种模型（修正的Gompertz、Cone和Logistic模型）进行厌氧发酵动力学分析。结果表明，TS浓度3%产甲烷量最高，累计产甲烷量258.07 mL·g^-1 VS。随TS浓度升高（3% ~ 7%），延滞期时间相应延长（19 ~ 32 d）。挥发性脂肪酸含量（volatile fatty acids，VFAs）在3种TS浓度中均呈先升高后降低趋势。3种TS浓度化学需氧量（chemical oxygen demand，COD）平均消解率为60.19% ~ 68.53%。通过动力学分析表明，Cone模型相比修正的Gompertz与Logistic模型，具有较高的拟合优度（R²=0.992 3 ~ 0.997 8），较低偏差程度。研究表明，TS浓度3%为最适宜的发酵浓度。其具有最高的甲烷产量，最短的延滞期，有机酸积累较少。Cone模型为最佳拟合及预测混合花卉秸秆厌氧发酵累计产甲烷量的动力学模型。

Study on methane production performance and kinetics of anaerobic fermentation of mixed flower straw

In order to study the anaerobic fermentation characteristics of mixed flower straw, flower straws of Rosa Rugosa, Lilium lancifolium, Gypsophila paniculata and Helianthus annuus were mixed with domesticated pig and cow manure to carry out anaerobic fermentation. Three total solids (TS) concentrations (3%, 5% and 7%) were used to investigate the characteristics of methane production and system stability. The characteristics of anaerobic fermentation kinetics were analyzed by using the modified Gompertz, Cone and Logistic models. The results showed that the methane production with TS concentration of 3% was the highest, and the cumulative methane production was 258.07 mL·g^-1 VS. With the increase of TS concentration (3% - 7%), the lag phase was prolonged (19 - 32 d). The content of volatile fatty acids (VFAs) in the three TS concentrations increased first and then decreased. The average digestion rate of chemical oxygen demand (COD) of three TS concentrations was 60.19% - 68.53%. Through kinetic analysis, the Cone model had a higher goodness of fit (R² = 0.992 3 - 0.997 8) and a lower degree of deviation than the modified Gompertz and Logistic models. Studies showed that 3% TS concentration is the most suitable fermentation concentration, with the highest methane production, the shortest lag phase, and the least organic acid accumulation with the highest methane production, the shortest lag phase, and the least organic acid accumulation. The Cone model is the kinetic model that best fits and predicts the cumulative methane production from anaerobic fermentation of mixed flower straws.