Here, we experimentally
investigate an alternative membrane capacitive
deionization (MCDI) system cycle, which aims to reduce the required
electrical energy demand for water treatment. The proposed heat and
power combined MCDI system utilizes waste heat to control the electrostatic
potential of the charged electrodes during the charging (desalination)
and discharging (energy recovery) processes. The experimental findings
suggest that with an increase in the temperature of the brine from
20 to 50 °C, the electrical energy consumed can be reduced by
nearly 10%. We also show that the dependence of electrostatic potential
on concentration may limit energy recovery performance (power), when
moving toward higher water recoveries. Alternative desalination cycles
can be further explored through evaluating non-isothermal and non-adiabatic
system operation
