<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Municipal wastewater treatment results in the production of large quantities of sewage sludge, which requires proper environmentally accepted management before final disposal. Sewage sludge is a by-product of current wastewater treatment technologies. Sewage sludge disposal depends on the sludge treatment methods used in the wastewater treatment plant (anaerobic or aerobic digestion, drying, etc.). Taking into consideration presented given this information, a study concerning the effects of wastewater treatment processes and sewage sludge drying method on the sewage sludge gasification gas parameters was performed. Gasification is a prospective alternative method of sludge thermal treatment. For the purpose of experimental investigations, a laboratory fixed bed gasifier installation was designed and built. Two types of sewage sludge feedstock, SS1 and SS2, were analyzed. Sewage sludge SS1 came from a wastewater treatment plant operating in the mechanical and biological system while sewage sludge SS2 was collected in a mechanical, biological and chemical wastewater treatment plant with simultaneous phosphorus precipitation. The sludge produced at the plants was subject to fermentation and then, after being dehydrated, dried in a cylindrical drier on shelves heated up to 260ºC (sewage sludge SS1) and using hot air at a temperature of 150ºC in a belt drier (sewage SS2). The analysis shows that the sewage sludge properties strongly depend on the wastewater sources and the wastewater treatment processes. The gasification results, presented as a function of the amount of gasification agent, show that the greater oxygen content of SS1 caused a reduction in the reaction temperature. Paradoxically, this effect caused an increase in the quantity of combustible components in the gas. As expected, increasing the air flow rate caused a decrease in the heating value of the gas produced. A higher amount of oxidizer increases the amounts of noncombustible species and the volumetric fraction of nitrogen, thus reducing the heating value of the obtained gas. The higher hydrogen content in SS1 affects the gasification gas composition. As a result, combustible components are the majority of the syngas.</p></abstract>

Municipal wastewater treatment results in the production of large quantities of sewage sludge, which requires proper environmentally accepted management before final disposal. Sewage sludge is a by-product of current wastewater treatment technologies. Sewage sludge disposal depends on the sludge treatment methods used in the wastewater treatment plant (anaerobic or aerobic digestion, drying, etc.). Taking into consideration presented given this information, a study concerning the effects of wastewater treatment processes and sewage sludge drying method on the sewage sludge gasification gas parameters was performed. Gasification is a prospective alternative method of sludge thermal treatment. For the purpose of experimental investigations, a laboratory fixed bed gasifier installation was designed and built. Two types of sewage sludge feedstock, SS1 and SS2, were analyzed. Sewage sludge SS1 came from a wastewater treatment plant operating in the mechanical and biological system while sewage sludge SS2 was collected in a mechanical, biological and chemical wastewater treatment plant with simultaneous phosphorus precipitation. The sludge produced at the plants was subject to fermentation and then, after being dehydrated, dried in a cylindrical drier on shelves heated up to 260ºC (sewage sludge SS1) and using hot air at a temperature of 150ºC in a belt drier (sewage SS2). The analysis shows that the sewage sludge properties strongly depend on the wastewater sources and the wastewater treatment processes. The gasification results, presented as a function of the amount of gasification agent, show that the greater oxygen content of SS1 caused a reduction in the reaction temperature. Paradoxically, this effect caused an increase in the quantity of combustible components in the gas. As expected, increasing the air flow rate caused a decrease in the heating value of the gas produced. A higher amount of oxidizer increases the amounts of noncombustible species and the volumetric fraction of nitrogen, thus reducing the heating value of the obtained gas. The higher hydrogen content in SS1 affects the gasification gas composition. As a result, combustible components are the majority of the syngas.

Influence of Wastewater Treatment and The Method of Sludge Disposal on the Gasification Process

Institute of Thermal Technology, Silesian University of Technology, ul. Konarskiego 22, 44-100 Gliwice, Poland, phone +48 32 237 29 83, fax +48 32 237 28 72

Institute of Water and Wastewater Engineering, Silesian University of Technology, ul. Konarskiego 18, 44-100 Gliwice, Poland, phone +48 32 237 16 98, fax +48 32 237 10 47

Ecological Chemistry and Engineering S

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

Wpływ Oczyszczania ścieków I Sposobu Zagospodarowania Osadów ściekowych Na Proces Zgazowania

Municipal wastewater treatment results in the production of large quantities of sewage sludge, which requires proper environmentally accepted management before...

Influence of Wastewater Treatment and The Method of Sludge Disposal on the Gasification Process

Published Online: Jul 08, 2014

Page range: 255 - 268

DOI: https://doi.org/10.2478/eces-2014-0020

Keywords
wastewater treatment, sludge treatment, sewage sludge properties, gasification, uel properties, gasification gas parameters

© 2014 Sebastian Werle and Mariusz Dudziak

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

Influence of Wastewater Treatment and The Method of Sludge Disposal on the Gasification Process

Published Online: Jul 08, 2014

Page range: 255 - 268

DOI: https://doi.org/10.2478/eces-2014-0020

Keywordswastewater treatment, sludge treatment, sewage sludge properties, gasification, uel properties, gasification gas parameters

© 2014 Sebastian Werle and Mariusz Dudziak

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

Keywords
wastewater treatment, sludge treatment, sewage sludge properties, gasification, uel properties, gasification gas parameters