Anaerobic Treatment of Tetra-Methyl Ammonium Hydroxide (TMAH) Containing Wastewater

Abstract

Toxicity of tetra-methyl ammonium hydroxide (TMAH) was investigated in an upflow anaerobic sludge bed (UASB) by anaerobic toxicity assay test. System performance was determined by monitoring total organic carbon (TOC) and ion chromatograph (IC) analysis. The result indicates that TMAH concentration less than 10000 mg/L is nontoxic to the anaerobic archaea. TMAH containing in the wastewater was completely degraded under anaerobic condition and was transferred to biogas (CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> and CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) and NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> . The maximum volumetric loading of UASB is 6.95 kg TMAH/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -day (4.0 kg TOC/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -day) and 7.30 kg TMAH/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -day (4.1 kg TOC/m -day) for synthetic wastewater and wastewater from a full-scale thin-film transistor liquid crystal display manufacturing industry during the 240-day experiment, respectively. The removal efficiencies of THAM containing wastewater were both higher than 95% treated by UASB.