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ARS Home » Southeast Area » Florence, South Carolina » Coastal Plain Soil, Water and Plant Conservation Research » Research » Publications at this Location » Publication #402277
Research Project: Innovative Manure Treatment Technologies and Enhanced Soil Health for Agricultural Systems of the Southeastern Coastal Plain

Location: Coastal Plain Soil, Water and Plant Conservation Research

Title: Hydrochar stability: understanding the role of moisture, time and temperature in its physiochemical changes

Author
item MARZBAN, NADER - Leibniz Institute
item LIBRA, JUDY - Leibniz Institute
item Ro, Kyoung
item PAIAGUA, DANIELA - Leibniz Institute
item ROTTER, VERA - Leibniz Institute
item STURM, BARBARA - Leibniz Institute
item FILONENKO, SVITLANA - Max Planck Institute Of Colloids And Interfaces

Submitted to: Biochar
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/21/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: Hydrothermal carbonization (HTC) technology can be used to convert the low-value wet biomass into value-added products such as and a carbonaceous solid called hydrochar. However, only limited information is available about the potential physiochemical changes that occur post-production. Understanding these changes is crucial for future practical applications. Here we study the effect of storage temperature, -18, 4, and 20 degree Celsius (°C(, over one-year period on selected organics, and inorganic compounds of dry (DH) and wet (WH) hydrochars produced from hydrothermal carbonization of digested cow manure in a HTC reactor. The results show that the organic compounds (e.g., sugars, acids, and aromatics) in the stored samples at week 52 were considerably higher than their control values, disregarding the storage temperature. Inorganics decreased after one year of storage, with no significant difference between dry and wet hydrochar. In general, the high stability of DH, particularly when stored at 18°C, makes it a suitable option for many applications. Optimal storage conditions for hydrochar are suggested to ensure retaining its properties.

Technical Abstract: Several studies have been conducted to optimize the hydrothermal carbonization (HTC) process conditions for producing hydrochar for biofuel, soil, and environmental applications. However, limited information is available about the potential physiochemical changes that occur post-production. Understanding these changes is crucial not just for shaping future research plans, but also for future practical applications. Here we study the effect of storage temperature, -18, 4, and 20 degree Celsius (°C(, over one-year period on selected organics, and inorganic compounds of dry (DH) and wet (WH) hydrochars produced from hydrothermal carbonization of digested cow manure in a 18.7-liter HTC reactor. Comparison of the WH and DH control values showed that drying the WH does not result in the same composition of organic compounds. We report that the sample handling of the hydrochar had a large effect on the organic contents. Results showed that storage time significantly impacted changes in both WH and DH, with a large effect on organic content. The results show that the organic compounds (e.g., sugars, acids, and aromatics) in the stored samples at week 52 were considerably higher than their control values, disregarding the storage temperature. These considerable changes were observed after week 12. Inorganics decreased after one year of storage, with no significant difference between dry and wet hydrochar. In general, the high stability of DH, particularly when stored at 18°C, makes it a suitable option for many applications. Optimal storage conditions for hydrochar are suggested to ensure retaining its properties.