高温厌氧下腐殖土对改善活性污泥性质的影响

Improvement of Humus Soil on Activated Sludge Properties Under Condition of Thermophilic Anaerobic Digestion

摘要:

以提高活性污泥脱水性能、减量化、稳定化为目标，通过考察毛细吸水时间、有机元素组成、有机物分子量分布、傅立叶红外光谱等指标，探讨在55 °C高温厌氧条件下腐殖土的投加量、反应时间对活性污泥脱水性能、元素组成及结构特征的影响.研究结果表明，污泥脱水性能随腐殖土投加量的增加而提高，且脱水时间减少9.5%~38.4%；在腐殖土的作用下污泥中富里酸（FA）相对分子量分布指数Mw/Mn随投加量递减，小分子量有机物数量的比值由50%提升至70%；污泥中腐殖酸（HA）的傅立叶红外光谱图中腐殖土投加前后在1 654，1 540，2 925 cm-1峰处有明显的降低，表明腐殖土投加增强HA芳构化程度，提高处理后污泥的稳定性和成熟度；有机元素、总有机碳分析亦得到类似的结论.

Abstract:

This study aims to improve the dewater ability and the stability of the activated sludge with the sludge production being reduced. The parameters, such as capillary suction time (CST), elemental compositions, distribution of organic matter molecular weights and Fourier transform infrared spectrum were investigated to study the influence of humus soil on activated sludge properties under the condition of thermophilic anaerobic digestion (at 55 °C). The CST results show that humus soil can greatly improve dewater ability of the sludge. The Mw/Mn of FAs isolated from activated sludge decreases according to the dosage of humus soil, and the micromolecular proportion raises from 50% to 70%. All HAs isolated from activated sludge show similar spectra with different intense absorbance during the region of 1 654, 1 540, 2 925 cm-1 which suggests that humus soil improves the aromatization degree and the stability of activated sludge. Similar results are also found in organic elemental and total organic carbon analysis.