Abstract

In this study, a lab-scale upflow anaerobic sludge blanket (UASB) reactor was applied to the treatment of artificial electronics industry wastewater containing tetramethylammonium-hydroxide (TMAH), monoethanolamine (MEA), and isopropyl-alcohol (IPA) in order to evaluate process performance and degradation properties. During 800 days of operation, 96% efficiency of chemical oxygen demand (COD) removal was stably achieved at an organic loading rate of 8.5 kgCOD/m³/day at 18–19 °C. MEA degradation, carried out by acid-forming eubacteria, was confirmed within a week. The physical properties of the retained granular sludge were degraded by feeding with TMAH wastewater, but maintained by feeding with MEA wastewater due to an accumulation of species from the genus Methanosaeta and family Geobacteraceae. Analysis of the microbial community structure via SEM and 16S rRNA genes showed a proliferation of Methanomethylovorans-like cells and Methanosaeta-like cells at the surface and in the core of the granular sludge with TMAH, MEA and IPA acclimation. Furthermore, a batch degradation experiment confirmed that process inhibition due to increasing chemical concentration was relatively stronger for TMAH than for MEA or IPA. Thus, controlling the TMAH concentration of the influent to below 1 gCOD/L will be important for the stable treatment of electronics industry wastewater by UASB technology.

摘要

在这项研究中，实验室规模的上流厌氧污泥床（UASB）反应器用于处理包含四甲基氢氧化铵（TMAH），单乙醇胺（MEA）和异丙醇（IPA）的人造电子工业废水。工艺性能和降解性能。在运行800天的过程中，在18–19°C下，有机负荷速率为8.5 kgCOD / m ³ / day时，稳定地实现了96％的化学需氧量（COD）去除效率。在一周内证实了通过酸形成真细菌进行的MEA降解。饲喂TMAH废水会降低保留的颗粒污泥的物理性能，但由于甲烷菌属和甲烷菌属物种的积累，通过饲喂MEA废水可以保持颗粒状污泥的物理性能。土杆菌科。通过SEM和16S rRNA基因对微生物群落结构的分析表明，通过TMAH，MEA和IPA驯化，甲基污泥表面和核心中的甲基甲基甲氧戊酸类细胞和甲烷菌属类细胞增殖。此外，分批降解实验证实，TMAH相对于MEA或IPA而言，由于化学浓度增加而产生的过程抑制作用相对较强。因此，将进水的TMAH浓度控制在1 gCOD / L以下对于通过UASB技术稳定处理电子工业废水至关重要。