Abstract:
Despite the extensive use of engineered hydrochar (EHC) for contaminants adsorption in
water, little is known about the scaling-up of EHC production which has kept the technology at a low
readiness level (TRL). Full-scale EHC production was simulated to help bridge this knowledge gap. A
systematic analysis was performed where EHC was produced from rice straw using hydrothermal
carbonization (HTC) at 200 ◦C with iron addition. A techno-economic evaluation model was employed to
simulate the production process and to estimate energy requirements, configuration, and cost scenarios for
the HTC process. The minimum selling price (MSP) analysis of the engineered hydrochar was found to
be almost half compared to the market price for other similar sorbents ($ 76/t vs. $136/t) suggesting that
EHC production is feasible for scaling up. Finally, as a trial, the resulting material was tested for its
efficacy in the adsorption of an anionic organic contaminant (e.g., Congo Red, C32H22N6Na2O6S2) in
water to identify its potential for water treatment. Experimental results showed that EHC adsorbed > 95%
CR suggesting significant adsorption capability and feasibility for production scale-up.
