A team of researchers associated with the Clean&Circle Competence Centre has published a new scientific article in the international peer-reviewed journal Environments. The article is titled “Microbiological and Chemical Insights into Plasma-Assisted Disinfection of Liquid Digestate from Wastewater Treatment Plant ‘Kubratovo’” and was published in volume 13, issue 2 of the journal (2026).

The team behind the publication includes young researchers, including students, as well as experienced scientists from the centre – Lyubomira Gelanova, Polina Ilieva, Irina Schneider, Nora Dinova, Yovana Todorova, Elmira Daskalova, Margarita Antonova, Yana Topalova and Evgenia Benova.

The study explores the possibilities of using plasma technologies for the disinfection of liquid digestate, a by-product of biogas production from excess sludge generated during the wastewater treatment process of the city of Sofia. This product contains valuable inorganic substances and organic matter, but it often also includes pathogenic microorganisms, which limits its safe use.

Within the framework of the study, the scientists examined the effect of two types of plasma sources on the microbiological indicators and chemical composition of liquid digestate from the “Kubratovo” Wastewater Treatment Plant in Sofia. The results show that plasma treatment can achieve a very high degree of disinfection, including almost complete elimination of bacteria such as E. coli, Salmonella, and other indicators of sanitary contamination.

The obtained results demonstrate the potential of plasma technologies to improve the sanitary characteristics of digestate and support its safer use as a resource (liquid fertilizer) in agriculture. This is an important step toward the development of more effective solutions for waste management, resource recovery, and the implementation of circular economy principles.

Such scientific developments have direct importance for society, as they contribute to the development of technologies for a cleaner environment, safer wastewater management, and sustainable resource use.

The research was carried out under the projects

PNIIDIT №BG16RFPR002-1.014-0015 and № KP-06-IP China/4, funded by the Bulgarian National Science Fund, focusing on innovative solutions for energy and products derived from biodegradable waste.

The full text of the publication can be read here: https://www.mdpi.com/2076-3298/13/2/67

• Prev
• Next