Lessons within the course ‘On-site wastewater treatment’ for the ERASMUS students from Italy took place in the Water Centre on 18th October 2021. Physicochemical methods of testing of effluent from on-site wastewater treatment plant (dr hab. inż. Agnieszka Karczmarczyk) and microscopic analysis of sewage sludge (dr inż. Weronika kowalik) were presented.

      At first, students conducted field measurements of oxygen, pH and temperature in sewage sludge tank. The effluent and sewage sludge samples were collected for further laboratory analyses. Then the students tested physicochemical parameters of effluent such as BOD5, total solids, pH, colour and conductivity. Various groups of microorganisms living in sewage sludge were presented with the use of an optical microscope connected to a camera and a computer. Characteristic features of sessile ciliates, crawling ciliates, free swimming ciliates, naked and testate amoebae, flagellates, rotifers, nematodes, water mites and tardigrades were also described.