Transport behavior of pathogenic microorganisms in porous media and remediation capability of biochar: A review

The reuse of reclaimed water is a cost-effective way to alleviate water resource scarcity, but the residual pathogenic microorganisms inevitably influence the safety of its reuse. The transport behavior of pathogenic microorganisms in receiving porous media varies under different environmental factors and could be harmful to the natural ecology and even human health if not well treated. Biochar is expected to be an effective, environmentally-friendly functional material to inhibit the transport of pathogenic microorganisms, with unreplaceable advantages of low price, simple preparation method, and strong adsorption capacity. In the present paper, we start from identifying the transport behavior of typical pathogenic microorganisms in porous media, including protozoa, bacteria, and viruses, and then analyzing the primary factors affecting the transport of pathogenic microorganisms from the aspects of biology, physics, and chemistry. Furthermore, the effects of types of raw materials, pyrolysis temperature, particle size, and functional modification methods on the remediation performance of biochar for the transport of pathogenic microorganisms are clearly reviewed. Finally, we aim to clarify the transport rules of pathogenic microorganisms in porous media and provide biochar-based technical means for effectively inhibiting the transport of pathogenic microorganisms, thereby improving the ecological and health safety of reclaimed water reuse. HIGHLIGHTS Pathogenic microorganisms could spread widely through transport behavior in porous media.; The biological, physical, and chemical factors affecting the transport of pathogenic microorganisms were reviewed.; Parameters of biochar impacting the transport of pathogenic microorganisms were discussed.; Biochar is expected to have practical applications in inhibiting the transport of pathogenic microorganisms.;