橙皮精油对橙渣与剩余污泥厌氧共消化的毒性分析

Toxicity of Orange Peel Essential Oil to Anaerobic Co-digestion of Orange Residue and Excess Sludge

为了探究橙皮精油(EO)对橙渣与剩余污泥厌氧共消化系统的毒性,通过改变共消化底物中EO含量,研究其对厌氧共消化系统比产甲烷活性的影响及毒性抑制作用。结果表明,当EO为550和750 mg/kg时,其对厌氧发酵系统具有一定的促进作用,累积产气量较对照组分别提高了16.8%和21.1%;当EO为950和1 150 mg/kg时,厌氧共消化系统分别受到轻度抑制和中度抑制,其累积产气量较对照组分别降低了39.1%和49.9%;当EO为1 350 mg/kg时,厌氧共消化系统受到严重抑制,比产甲烷活性比对照组降低了98.4%,产气量几乎为0。毒性恢复实验表明,高含量EO(1 150和1 350 mg/kg)对厌氧共消化系统的微生物产生了生理毒素,辅酶F420含量显著降低,导致系统产甲烷活性受到严重抑制。

In order to investigate orange residue essential oil(EO) toxicity to orange residue and excess sludge anaerobic co-digestion system, effect of EO on specific methanogenic activity and toxicity inhibition of the anaerobic co-digestion system was explored by changing EO content in the co-digestion substrate. When EO content was 550 mg/kg and 750 mg/kg in the toxicity tests, it had certain promoting effect on the anaerobic fermentation system, and the cumulative gas yield was increased by 16.8% and 21.1% compared with that of the control group. When EO content was 950 mg/kg and 1 150 mg/kg, the anaerobic co-digestion system was slightly and moderately inhibited, and its cumulative gas yield decreased by 39.1% and 49.9% compared with that of the control group, respectively. When EO content was 1 350 mg/kg, the anaerobic co-digestion system was seriously inhibited, and the specific methanogenic activity decreased by 98.4% compared with that of the control group, and the gas yield was close to zero. Toxicity recovery experiment showed that high EO content(1 150 mg/kg, 1 350 mg/kg) produced certain physiological toxins to microorganisms in the anaerobic co-digestion system and coenzyme F420 content was significantly decreased. As a result, the methanogenic activity of the system was severely inhibited.