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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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Hydrogen production from urea in human urine using segregated systems
Ruben Asiain-Mira1, Collin Smith2, Patricia Zamora3
1Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS, Cambridge, UK; FCC Aqualia, Department of Innovation and Technology, Avda. del Camino de Santiago 40, 28050, Madrid, Spain.
Water Research
|August 15, 2022
Summary
This study presents a novel method to recover energy from human urine by isolating urea using activated carbon. This process efficiently decomposes urea into hydrogen fuel, offering a sustainable waste-to-energy solution.
Area of Science:
- Environmental Science
- Chemical Engineering
- Sustainable Energy
Background:
- Biological nitrogen removal in wastewater treatment is energy-intensive.
- Segregated wastewater systems can recover valuable compounds like urea.
- Conventional thermal treatment of urea is energy-demanding.
Purpose of the Study:
- To demonstrate a novel process for energy recovery from human urine.
- To reduce energy requirements for urea decomposition.
- To produce hydrogen fuel from a waste stream.
Main Methods:
- Urea separation from aqueous solution via activated carbon adsorption.
- Thermal decomposition of urea at 250°C for ammonia and CO2 generation.
- Catalytic decomposition of ammonia to produce hydrogen.
Main Results:
- Activated carbon showed consistent adsorption capacity over 5 cycles.
- The process yields hydrogen as a usable energy fuel.
- A city of 160,000 could produce 430 kg of hydrogen daily.
- Net energy production of 2,500 kWh/day is achievable.
- Wastewater treatment energy consumption can be reduced by 35%.
Conclusions:
- This novel process enables energy recovery from urea in segregated wastewater.
- It promotes a circular economy approach by valorizing waste streams.
- Significant energy savings and hydrogen production are feasible.
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