Research on the Characteristics of Heat Transfer and Mass Transfer of Imitation Heart Pulse Membrane Distillation

Membrane distillation, a separation technology, has drawn wide attention in industries such as seawater desalination and high-salinity wastewater treatment. However, conventional steady-flow operation suffers from flux decline and membrane fouling, while standard square-wave and sine-wave pulsations provide limited enhancement and stability. To address these issues, this study introduces heartbeat-mimicking pulsatile flow. Its effects on membrane distillation performance were evaluated through comparative (steady vs. pulsatile) experiments, a three-level orthogonal experiment, and tests with various feed solutions and modified membranes. Results show that, under baseline conditions, the heartbeat-mimicking pulsatile flow yielded a 17.5% higher average flux than steady flow, while its conductivity increase was only 25%, far below the 93% for steady flow. In the orthogonal experiment, the heartbeat-mimicking waveform accounted for the largest proportion of total variance (50.1%) among the tested parameters. Furthermore, compared to traditional sine or square waves, this biomimetic pulsation features unique acceleration-rest characteristics, making it highly applicable to complex feed solutions and effectively mitigating membrane fouling. This study aims to identify a new pulsation mode that can overcome the limitations of steady-flow membrane distillation.