Passively improving liquid sorbent based atmospheric water generation by integration of fuel cell waste products

Although interfacial atmospheric water generation is a new concept that can generate freshwater from renewable energy, its water generation rate is too low for widespread use. This paper proposes to integrate the fuel cell to a similar device but instead uses the electrochemically generated waste heat to drive the regeneration process of the liquid sorbent material. Furthermore, the electrochemically generated water is used to increase the relative humidity of the incoming air. Thus, by solely relying on the fuel cell waste products, water recovery rates that are theoretically higher than direct atmospheric water generation are achieved. A steady-state physics model based on the difference in water partial pressure to achieve water absorption and desorption is used to analyze the liquid sorbent device's performance. Furthermore, the effect of various design parameters such as the salt mass fraction, the fuel cell operating power, the ambient relative humidity, etc. have been studied. Results demonstrate that up to 1.8 kg/h and 0.82 kg/(m(2)h) of liquid water can be obtained by fuel cells with an operating temperature range that is consistent with the high-temperature proton exchange membrane fuel cell. This implementation would allow an FC waste heat utilization ratio of up to 0.8. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

This paper proposes an innovative approach to integrate fuel cells into a similar device, utilizing electrochemically generated waste heat to drive the regeneration process of liquid sorbent material and achieving higher water recovery rates. Through model analysis and parameter studies, it is concluded that fuel cells can obtain a certain amount of liquid water.