Co-hydrothermal carbonization of sewage sludge and lignocellulosic biomass: Fuel properties and heavy metal transformation behaviour of hydrochars

Co-Hydrothermal Carbonization of Sewage Sludge with Wood Chip: Fuel Properties and Heavy Metal Transformation Behavior of Hydrochars

“…It was observed that SS had high levels of Mn, Zn, and Cr but relatively low concentrations of As. This was similar to the result of our previous study, 5 where the SS in Guangzhou also had high concentrations of Zn and Cr. This might be related to the high degree of industrial density and human activities in south China.…”

“…In our previous work, the addition of cellulose, xylan, and lignin was observed to be effective in reducing (F1+F2) fractions of Ni and Cr and the hydrochar from SS, and lignin exhibited a low potential ecological risk index. However, it was detected that the concentration of Zn did not exhibit a noticeable variation.…”

“…In China, the output of SS was 6.25 million in 2013 and more than 90 million tons of SS will be produced by 2023 . Without effective handling and disposal, SS is likely to pose a huge threat to the ecological environment and human. , In the past, an effective and economical strategy for SS management was dumping in landfill . The nutrients in SS including nitrogen, phosphorus, and other micronutrients can improve the biological properties of the soil and reduce the use of expensive synthetic fertilizers.…”

Hydrochar derived from municipal sludge through hydrothermal processing: A critical review on its formation, characterization, and valorization

“…Huang et al (2021) found that HTC treatment (150-275 °C) could transform metals into insoluble sulfides (e.g., Cu-Fe-or Zn-Fe-sulfides) and completely reduce high-toxic Cr(VI) into low-toxic Cr(III) in hydrochar derived from WAS and DS. Besides, Lu et al (2021) reported that co-HTC of MS with lignocellulosic biomass (e.g., cellulose, lignin, and xylan) could further promote the immobilization of heavy metals (e.g., Cr, Cu, Ni, and Zn) along with improved fuel quality of hydrochar. In general, the bioavailability and toxicity of heavy metals are highly reduced after HTP compared to raw MS.…”

Upgrading fuel potentials of waste biomass via hydrothermal carbonization

“…Additionally, elemental analysis (C, H, N, S) of all samples was performed by using a Vario EL III; C, H, N, S/O Elemental Analyzer (Elementar, Germany) equipped with a thermal conductivity detector (TCD), while O contents (%) were calculated by subtracting the sum of the obtained elemental values from 100 %. The HHV and ED values were calculated from the results of elemental analysis according to equations ( 1) and ( 2), respectively [16,17]:…”