<abstract xmlns="http://www.w3.org/1999/xhtml">The presence of pathogenic microorganisms in sewage sludge is one of the crucial factors affecting their use in agriculture and in nature. An appropriate method of sludge hygienization can contribute to the reduction of the presence of pathogenic microbes in the sludge or to their complete elimination. This study presents the possibility of using dry ice in the hygienization of surplus activated sludge. The scope of survey covered microbiological as well as physiochemical analyses of the sludge. The microbiological analyses conducted show the hygienization effect of dry ice on surplus activated sludge such as the reduction of the total number of bacteria as well as of pathogenic bacteria. In the case of sludge to dry ice 1:1 voluminal ratio, the total number of bacteria has been reduced by 76%, the number of <italic>Salmonella</italic> sp. rods by 90%, and <italic>Clostridium perfringens</italic> by 85%. The results of physiochemical analyses confirmed the destructive effect that dry ice has over microorganisms. The disintegration of microbes by means of dry ice contributed to the increase of supernatant liquid turbidity and to the release of organic matter. For the sludge to dry ice 1:1 voluminal ratio, an increase in turbidity of supernatant liquid by 320 mg SiO2 dm-3 has been proven, as well as an increase in the value of CODCr by 549 mg O2 dm-3, which indicates the release of organic matter into the liquid phase.</abstract>

The presence of pathogenic microorganisms in sewage sludge is one of the crucial factors affecting their use in agriculture and in nature. An appropriate method of sludge hygienization can contribute to the reduction of the presence of pathogenic microbes in the sludge or to their complete elimination. This study presents the possibility of using dry ice in the hygienization of surplus activated sludge. The scope of survey covered microbiological as well as physiochemical analyses of the sludge. The microbiological analyses conducted show the hygienization effect of dry ice on surplus activated sludge such as the reduction of the total number of bacteria as well as of pathogenic bacteria. In the case of sludge to dry ice 1:1 voluminal ratio, the total number of bacteria has been reduced by 76%, the number of Salmonella sp. rods by 90%, and Clostridium perfringens by 85%. The results of physiochemical analyses confirmed the destructive effect that dry ice has over microorganisms. The disintegration of microbes by means of dry ice contributed to the increase of supernatant liquid turbidity and to the release of organic matter. For the sludge to dry ice 1:1 voluminal ratio, an increase in turbidity of supernatant liquid by 320 mg SiO2 dm-3 has been proven, as well as an increase in the value of CODCr by 549 mg O2 dm-3, which indicates the release of organic matter into the liquid phase.

Hygienization of Surplus Activated Sludge By Dry Ice

Department of Microbiology and Environmental Biotechnology, Institute of Environmental Protection and Engineering, University of Bielsko-Biala, ul. Willowa 2, 43-309 Bielsko-Biała, Poland, phone +48 33 827 91 57

Ecological Chemistry and Engineering S

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Hygienization of Surplus Activated Sludge By Dry Ice"}

The presence of pathogenic microorganisms in sewage sludge is one of the crucial factors affecting their use in agriculture and in nature. An appropriate...

Hygienization of Surplus Activated Sludge By Dry Ice

Publicado en línea: 02 feb 2015

Páginas: 651 - 660

DOI: https://doi.org/10.1515/eces-2014-0047

Palabras clave
surplus activated sludge, dry ice, sp.,

© 2015 Nowicka et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Hygienization of Surplus Activated Sludge By Dry Ice

Publicado en línea: 02 feb 2015

Páginas: 651 - 660

DOI: https://doi.org/10.1515/eces-2014-0047

Palabras clavesurplus activated sludge, dry ice, sp.,

© 2015 Nowicka et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Palabras clave
surplus activated sludge, dry ice, sp.,