粒径对好氧颗粒污泥储存稳定性的影响

Effect of particle size on storage stability of aerobic granular sludge

研究了混合粒径与不同粒径好氧颗粒污泥(AGS)在储存过程中的三维结构、质量变化、微生物活性以及理化特性的变化规律。经过室温(16~25℃)下31天的储存,污泥的三维结构均保持较好,未出现明显解体现象。混合粒径的AGS在储存前20天,其质量和比耗氧速率(SOUR)下降缓慢,胞外聚合物(EPS)先减小后上升。20天之后由于厌氧菌在竞争中逐渐占得优势,其质量减小了46.3%,EPS与SOUR分别下降69.0%和72.7%,导致稳定性随之下降。不同粒径AGS经过储存后,其颜色仍为橙黄色且结构完整;1~2mm和3~4mm粒径的AGS质量减小(分别为49.1%和53.9%)较大,且SOUR和EPS下降了亦较大;0.3~1mm粒径的AGS质量减小较少,EPS下降较少,但SOUR下降幅度较大,而2~3mm粒径的质量仅减小了33.7%、SOUR下降幅度最小(39.8%),EPS下降幅度也相对较小(58.7%),表明其在储存过程中能保持较好的活性与稳定性。

The three-dimensional structure,mass change,biological activity and physical and chemical properties of different particle sizes and mixed particle size aerobic granule sludges (AGS) during storage were studied.After 31 days of storage at room temperature (16-25℃),the sludge structure remained good and there was no obvious disintegration.In the first 20 days of storage,the quality and specific oxygen uptake rate (SOUR) of the mixed particle size AGS decreased slowly.Extracellular polymer (EPS) first decreased and then raised.Then,due to the anaerobic bacteria took advantage of the competition,its quality (46.3%),EPS (69.0%) and SOUR (72.7%) decreased significantly,resulting in a decrease in stability.After storage of different particle size AGS,the color was still orange and the structure was complete.The AGS mass loss of 1-2mm and 3-4mm particle size (49.1% and 53.9%,respectively) was larger,and the decrease of SOUR and EPS was also larger.The mass of AGS with 0.3-1mm particle size decreased lesser,and EPS decreased lesser,but the decrease of SOUR was larger,while the quality of 2-3mm particle size only decreased by 33.7%.The decrease of SOUR was the smallest (39.8%).The EPS decline was relatively small (58.7%),which showed that it could maintain good activity and stability during the storage.