Influence of Hydrothermal Carbonization on Composition, Formation and Elimination of Biphenyls, Dioxins and Furans in Sewage Sludge

Energies

Achim Loewen¹  Fabian Gievers¹  Volker Zelinski¹  Heiner Brookman¹  Jan Ohlert² 

[1] Faculty of Resource Management, University of Applied Sciences and Arts (HAWK), 37075 Göttingen, Germany;Institute of Chemistry, University of Oldenburg, 26129 Oldenburg, Germany;

关键词: hydrothermal carbonization;    sewage sludge;    dioxins;    furans;    polychlorinated biphenyl;   

DOI  :  10.3390/en11061582

来源: DOAJ

【 摘 要 】

In many areas of application, the influence of hydrothermal carbonization (HTC) on the composition of organic pollutants is still unexplored. In this study, sewage sludge (SS) was carbonized and the input as well as the hydrochar were examined for the organic pollutants: polychlorinated biphenyls (PCB), polychlorinated dibenzo-dioxins (PCDDs), and polychlorinated dibenzo-furans (PCDFs). The process temperatures of carbonization were 200 °C, 220 °C, and 240 °C and the holding time was 5 h for all tests. The total concentration of PCBs was relatively stable for all temperatures, whereas the toxicity equivalent (WHO-TEQ) at 200 °C and 220 °C increases compared to the input material. The strongest impact on toxicity was observed for PCDDs where concentrations were reduced for higher temperatures, whereas the toxicity increases by more than 16 times for temperatures of 240 °C. The concentrations and toxicity of PCDFs were reduced for all carbonization temperatures. In hydrochar from HTC at 240 °C, the limit values for the application of SS in German agriculture have been exceeded. The results indicate that the process conditions for HTC should be controlled also for SS with average contamination if the hydrochar is to be used as material, especially in agriculture.

【 授权许可】

Unknown