Effect of temperature on the sulfur fate during hydrothermal carbonization of sewage sludge. (May 2020)

• Record Type: Journal Article
• Authors: Wang, Zhexian; Zhai, Yunbo; Wang, Tengfei; Peng, Chuan; Li, Shanhong; Wang, Bei; Liu, Xiangmin; Li, Caiting
• Is Part Of: Environmental pollution. Volume 260(2020)
• Publication Date: 2020-05
• Subjects: Hydrothermal carbonization -- Sewage sludge -- Sulfur balance -- Evolution mechanism; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.114067
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: To understand the effect of reaction temperature on sulfur during hydrothermal carbonization (HTC) of sewage sludge (SS), seven group of temperature (180–300 °C) were chosen to investigate the distributions and evolution of sulfur-containing compounds in hydrochar and the liquid products. Elemental analysis, X-ray photoelectron spectroscopy (XPS), and X-Ray powder diffraction (XRD) were used to characterize the distribution of sulfur in hydrochar. The concentrations of sulfate ions and sulfide were determined in the liquid sample. The experimental results showed that as the temperature increased, the O/C ratio decreased because of the improved carbonization degree of SS. After hydrothermal carbonization, 90% of the sulfur in SS remained in hydrochar. As the temperature increased, the amount of sulfur in the liquid, mainly in the form of sulfate ions, tended to decrease. However, the experimental results for the gas phase were the opposite of the liquid phase. Graphical abstract: Image 1 Highlights: The sulfur species distribution and evolution in sewage sludge were investigated. Increasing temperature enhanced stable thiophene and sulfate content. Sulfate ion was identified as main sulfur species in liquid fraction. Sulfur species depended on HTC temperature. Abstract : This manuscript discusses the evolution and transformation of sulfur species in sewage sludge for different hydrothermal carbonization temperature.