Bioinspired polyethylene/boron nitride woven mesh integrating heterogeneous wettability and radiation cooling for water recycling of cooling tower.

Abstract

Industrial cooling towers, consuming ∼50 % of global industrial water, incur significant losses via evaporation, drift, and blowdown. To address this challenge, we developed a melting blending and extrusion-drawing method to fabricate spider-web inspired woven mesh based on polyethylene/boron nitride composites. The bioinspired mesh integrates heterogeneous wettability with radiative cooling to efficiently harvest water from the cooling tower. The bioinspired woven mesh exhibited a strong mid-infrared emissivity of 96.46 % and a temperature reduction of 6.68 °C is achieved. The micro/nanostructure-induced heterogeneous wettability synergized with radiative cooling to enhance droplet nucleation and growth, boosting water recycling efficiency by 54.67 % compared to conventional meshes. When applied to the water recycling of the cooling tower, the bioinspired woven mesh achieved a water recycling rate of 13.58 kg m⁻² h⁻¹ with a recovery efficiency of 71.46 %. Furthermore, the water recycling efficiency and material properties of the bioinspired woven mesh remained stable after 30 days of outdoor testing and 72 h of continuous UV irradiation of 0.5 W cm⁻², ensuring long-term durability for sustainable water recovery in industrial applications. Critically, global implementation of this spider-web-inspired woven mesh in industrial cooling towers could conserve ∼149.0 billion m³ of water annually. This rapid, efficient strategy addresses key challenges in cooling tower water recycling through synergistic heterogeneous wettability and radiative cooling.