Zhu Jun, Wu Sarah, Shen Jiacheng
a Department of Biological and Agricultural Engineering , University of Arkansas , Fayetteville , Arkansas , USA.
b Department of Biological Engineering , University of Idaho , Moscow , Idaho , USA.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2019;54(3):231-237. doi: 10.1080/10934529.2018.1546494. Epub 2018 Dec 27.
In this study, the effects of three total solids levels (2%, 5% and 10% TS) of the mixtures of poultry litter and wheat straw at different percent volatile solids from wheat straw (0%, 25% and 50% VSWS), free ammonia nitrogen (FAN) and C/N ratio on co-digesting poultry litter with wheat straw were studied in batch experiments operated at 37 °C. The results showed that adjusting the substrate C/N ratio alone could not always result in high methane yields and biogas volumes. The maximum CH yield of 201 mL g initial VS was observed in the 5% TS category with VSWS being 50%. The highest specific biogas volume produced (318 mL g initial VS) was also obtained in the same solid category. A polynomial regression between FAN and the methanogenic activity was obtained with the correlation coefficient being 0.9472. A FAN inhibitory threshold concentration of 253.9 mg L was found, and a total loss of methane production occurred when the FAN concentration reached 1000 mg L. An optimal TS content for anaerobic digestion of poultry litter with wheat straw was around 4.15% to achieve the best biogas yield. Similarly, for digesting poultry litter without addition of wheat straw, the TS content should be kept at around 6.8%.
在本研究中，在37°C下进行的批次实验中，研究了不同麦秸挥发性固体百分比（0%、25%和50% VSWS）、游离氨氮（FAN）和碳氮比条件下，家禽粪便与麦秸混合物的三种总固体水平（2%、5%和10% TS）对家禽粪便与麦秸共消化的影响。结果表明，仅调节底物碳氮比并不总能获得高甲烷产量和沼气量。在总固体含量为5%、麦秸挥发性固体含量为50%的类别中，观察到最大甲烷产量为201 mL g初始挥发性固体。在相同固体类别中也获得了最高的特定沼气产量（318 mL g初始挥发性固体）。得到了FAN与产甲烷活性之间的多项式回归，相关系数为0.9472。发现FAN抑制阈值浓度为253.9 mg L，当FAN浓度达到1000 mg L时，甲烷产量完全丧失。家禽粪便与麦秸厌氧消化的最佳总固体含量约为4.15%，以实现最佳沼气产量。同样，对于不添加麦秸的家禽粪便消化，总固体含量应保持在6.8%左右。
