Polyhydroxyalkanoate accumulation experiments at pilot scale were performed with fullscale municipal waste activated sludge. Development of biomass PHA content was quantified by thermogravimetric analysis. Over 48 h the biomass reached up to 0.49 $\pm$ 0.03 gPHA/gVSS ($n=4$). Samples were processed in parallel to characterise the distribution of PHA in the biomass. Selective staining methods and image analysis were performed by Confocal Laser Scanning Microscopy. The image analysis indicated that nominally 55% of this waste activated sludge was engaged in PHA storage activity. Thus even if the biomass PHA content reached 0.49gPHA/gVSS, the accumulating fraction of the biomass was estimated to have attained about 0.64gPHA/gVSS. The combination of quantitative microscopy and polymer mass assessment enabled to distinguish the effect of level of enrichment in PHA storing bacteria and the average PHA storage capacity of the accumulating bacteria. The distribution of microbial 16S rRNA levels did not follow a measurable trend during PHA accumulation.

中试规模的聚羟基链烷酸酯积累实验是用全规模的城市垃圾活性污泥进行的。通过热重分析量化生物质PHA含量的发展。超过 48 小时，生物量达到 0.49$\pm$0.03 gPHA/gVSS ($n=4$）。并行处理样品以表征 PHA 在生物质中的分布。通过共聚焦激光扫描显微镜进行选择性染色方法和图像分析。图像分析表明，标称 55% 的这种废弃活性污泥从事 PHA 储存活动。因此，即使生物质PHA含量达到0.49gPHA/gVSS，估计生物质的积累部分也达到了约0.64gPHA/gVSS。定量显微镜和聚合物质量评估的结合能够区分 PHA 储存细菌的富集水平和累积细菌的平均 PHA 储存能力的影响。在 PHA 积累过程中，微生物 16S rRNA 水平的分布没有遵循可测量的趋势。