Correlating phosphorus transformation with process water during hydrothermal carbonization of sewage sludge via experimental study and mathematical modelling

2022 ◽  
Vol 807 ◽  
pp. 150750
Author(s):  
Xiaoyuan Zheng ◽  
Mengxuan Shen ◽  
Zhi Ying ◽  
Yuheng Feng ◽  
Bo Wang ◽  
...  
Keyword(s):  
Experimental Study ◽  
Sewage Sludge ◽  
Mathematical Modelling ◽  
Hydrothermal Carbonization ◽  
Process Water ◽  
Phosphorus Transformation

Feedwater pH affects phosphorus transformation during hydrothermal carbonization of sewage sludge

2017 ◽  
Vol 245 ◽  
pp. 182-187 ◽  
Author(s):  
Tao Wang ◽  
Yunbo Zhai ◽  
Yun Zhu ◽  
Chuan Peng ◽  
Tengfei Wang ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Hydrothermal Carbonization ◽  
Phosphorus Transformation

scholarly journals Optimizing the Hydrothermal Carbonization of Sewage Sludge—Response Surface Methodology and the Effect of Volatile Solids

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1225
Author(s):  
Tobias Blach ◽  
Markus Engelhart
Keyword(s):  
Reaction Time ◽  
Sewage Sludge ◽  
Response Surface ◽  
Reaction Temperature ◽  
Hydrothermal Carbonization ◽  
Process Water ◽  
Heating Value ◽  
Box Behnken Design ◽  
Water Load ◽  
Volatile Solids

This study focuses on identifying the optimum conditions of sewage sludge hydrothermal carbonization by Box–Behnken Design and on the effects of volatile solids on heating value and on process water load. To get insight into the solid and process water characteristics, we applied the Box–Behnken Design on the hydrothermal reaction temperature (190, 220, 250 °C), reaction time (0.5, 2.25, 4 h) and pH (3.9, 5, 6.1). The response surface of the liquid phase revealed decreasing dissolved organic carbon (DOC) concentrations with increasing temperature from 9446 mg/L (190 °C) to 7402 mg/L (250 °C) at 4 h reaction time. For the same hydrothermal conditions, NH4-N concentration increased from 754 to 1230 mg/L. Reaction temperature was identified as the most important process parameter, whereas reaction time and pH had only minor effects. Moreover, linear coefficients of the models were more decisive than the interrelation and quadratic coefficients. Volatile solids (VS) of the feedstock were found to significantly influence both the load of the process water and the change in heating value of the hydrochars. Process water load increased steadily with higher VS. The heating value only increased with more than around 65–80% VS in feedstock.

scholarly journals Sewage Sludge Treatment by Hydrothermal Carbonization: Feasibility Study for Sustainable Nutrient Recovery and Fuel Production

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2697
Author(s):  
Gabriel Gerner ◽  
Luca Meyer ◽  
Rahel Wanner ◽  
Thomas Keller ◽  
Rolf Krebs
Keyword(s):  
Liquid Phase ◽  
Sewage Sludge ◽  
Hydrothermal Carbonization ◽  
Economic Feasibility ◽  
Phosphorus Recovery ◽  
High Yield ◽  
Nutrient Recovery ◽  
Waste Biomass ◽  
Sludge Treatment ◽  
Sewage Sludge Treatment

Phosphorus recovery from waste biomass is becoming increasingly important, given that phosphorus is an exhaustible non-renewable resource. For the recovery of plant nutrients and production of climate-neutral fuel from wet waste streams, hydrothermal carbonization (HTC) has been suggested as a promising technology. In this study, digested sewage sludge (DSS) was used as waste material for phosphorus and nitrogen recovery. HTC was conducted at 200 °C for 4 h, followed by phosphorus stripping (PS) or leaching (PL) at room temperature. The results showed that for PS and PL around 84% and 71% of phosphorus, as well as 53% and 54% of nitrogen, respectively, could be recovered in the liquid phase (process water and/or extract). Heavy metals were mainly transferred to the hydrochar and only <1 ppm of Cd and 21–43 ppm of Zn were found to be in the liquid phase of the acid treatments. According to the economic feasibility calculation, the HTC-treatment per dry ton DSS with an industrial-scale plant would cost around 608 USD. Between 349–406 kg of sulfuric acid are required per dry ton DSS to achieve a high yield in phosphorus recovery, which causes additional costs of 96–118 USD. Compared to current sewage sludge treatment costs in Switzerland, which range between 669 USD and 1173 USD, HTC can be an economically feasible process for DSS treatment and nutrient recovery.

Hydrothermal carbonization characteristics of sewage sludge and lignocellulosic biomass. A comparative study

2019 ◽  
Vol 120 ◽  
pp. 166-175 ◽  
Author(s):  
Małgorzata Wilk ◽  
Aneta Magdziarz ◽  
Kandasamy Jayaraman ◽  
Monika Szymańska-Chargot ◽  
Iskender Gökalp
Keyword(s):  
Sewage Sludge ◽  
Comparative Study ◽  
Lignocellulosic Biomass ◽  
Hydrothermal Carbonization

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

Energies ◽  
2018 ◽  
Vol 11 (6) ◽  
pp. 1582 ◽  
Author(s):  
Heiner Brookman ◽  
Fabian Gievers ◽  
Volker Zelinski ◽  
Jan Ohlert ◽  
Achim Loewen
Keyword(s):  
Sewage Sludge ◽  
Organic Pollutants ◽  
Total Concentration ◽  
Hydrothermal Carbonization ◽  
Process Conditions ◽  
Limit Values ◽  
Composition Formation ◽  
Input Material ◽  
Dioxins And Furans ◽  
Toxicity Equivalent

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.

Sign in / Sign up

Export Citation Format

Share Document