Abstract
Microbial removal of nitrogen in wastewater was performed by biodegradable polycaprolactone (PCL) and the following results were obtained. Nitrogen in wastewater could be effectively removed by PCL, e.g. more than 70 % of total nitrogen (TN) was removed on the average after ten weeks. PCL degraded linearly with immsering time and its weight loss was ca.44 % after 10 weeks. The thickness of PCL plate decreased similarly from 0.5 mm to ca.0.2-0.3 mm, but it kept the original form. During the reaction, biofilm (microbial film) was formed on the surface of the plate and saturated at ca.1.0 mm. Increase in total organic carbon (TOC) and inorganic carbon (IC) in wastewater was observed. Slight changes in pH and suspended substances (SS), and formation of ammonium nitrogen and nitrite nitrogen were occurred. Measurement of molecular weights and spectroscopy such as IR and UV-V indicated that biodegradation of PCL occurred on its surface.
