Microscopic Analysis of Activated Sludge in Industrial Textile Wastewater Treatment Plant

The relationship between a quality of activated sludge microbiota and wastewater treatment plant (WWTP) operational stability has been defined in the past few decades. However, this dependence is not so clear in the case of industrial wastewater treatment. In this article, a very specific example of industrial textile wastewater treatment plant (ITWTP) is analyzed. Textile effluents are well known as highly contaminated wastewater containing many biodegradable compounds. Microscopic analysis included flocs morphology examination, attempts to evaluate the Sludge Biotic Index (SBI), and identification of dominant filamentous microorganisms. Routine operational control of ITWTP covered pH, temperature, redox potential, dissolved oxygen and COD measurements. The average ecosystem existing in the described ITWTP differed significantly compared to municipal WWTPs. The flocs were smaller and irregular. Filamentous bacteria did not cause foaming although filaments index reached 4. Nostocoida limicola I dominated with significant amounts of type 0041 and type 021N. The evaluation of SBI was impossible as the most of protozoan was in the form of cysts. The overall microbiota diversity correlated with COD removal in activated sludge unit of ITWTP.