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Industrial Research And Consultancy Centre
Patent
Conductive membrane and their Stacking for Enhanced Interfacial Evaporation (SiEVA) for Desalination, Water Recycling, and Near Zero Liquid Discharge Systems
Abstract
  • This invention used the laser-induced graphene (LIG) based Joule heaters for efficient water evaporation. 
  • It Addresses limitations of solar-driven interfacial evaporation: dependency on sunlight intensity and issues with salt deposition. 
  • It Investigates the impact of voltage on evaporation rates and benefits of stacking Joule heaters. 

    Key findings: 

  • Stacked heaters significantly enhance evaporation rates and reduce spatial footprint and thermal losses. 
  • Achieves up to 5 kg/m²/h evaporation rate at 10V, performs effectively even with seawater and exhibits self-cleaning properties to prevent salt buildup. Proposes a compact, efficient system for both small- and large-scale applications, integrating renewable energy sources.
Uniqueness of the Solution
  • Container-Based System: A liquid vapor generation system in a container, using an insulator member (foam or polyester sponge) and a wick (folded tissue paper). 
  • Stacked Heaters: Multiple heaters stacked on the wick, made from single or double- sided filters, and powered by an electrical source to control evaporation rate based on liquid weight loss. 
  • Stacked Configuration: Includes various configurations like SLIG (Single Laser- Induced Graphene), LILI (LIG-Insulator-LIG-Insulator) double stacking, LIIL (LIG- Insulator-Insulator-LIG) double stacking, DLIG (Double-sided Laser-Induced Graphene), and LILILI (LIG-Insulator-LIG-Insulator-LIG-Insulator) triple stacking for enhanced performance. 
  • Conductive Filters: Filters coated with conductive materials such as LIG, carbon cloth, or thin-film electrically conductive surfaces, created using specific laser techniques. 
  • Single-Sided Filter Fabrication: Single-sided filters made by lasing one side with a CO2 laser system. 
  • Double-Sided and Metal-Doped Filters: Double-sided filters created by casting a thin PES film and lasing both sides, and metal-doped filters made by incorporating nanoparticles into a polymer solution and lasing.
  • Dual Heating Mechanism: Combines Joule heating and solar energy, enabling effective water evaporation under varying environmental conditions. 
  • Laser-Induced Graphene (LIG): Utilizes LIG for efficient, localized heating, a novel application in water treatment. 
  • Stacked Configuration: Innovative stacked heater design significantly enhances evaporation rates compared to single-layer systems. 
  • Self-Cleaning Property: Exhibits good salt resistance and self-cleaning capabilities, reducing maintenance in high-salinity environments. 
  • Adjustable Heating Power: Allows fine-tuning of Joule heating to compensate for solar intensity variations, ensuring consistent performance.
Prototype Details

Materials: UP10 membrane, foam, tissue paper, PES polymer, copper tape Fabrication: LIG filters made using CO2 laser, JH created with copper tape Characterization: SEM, Raman, XPS, Contact Angle, Resistance, Temperature Joule Heating: Evaporation rate tested with different voltages, stacking configurations

Current Status of Technology

Early prototype development is in process

Technology readiness level

6

Societal Impact
  • Enhances Water accessibility: Provides clean water in scarce regions. 
  • Environmental Sustainability: renewable energy for sustainable water treatment. 
  • Cost-effective healthcare: Reduces costs with efficient sterilization.
Relevant Industries, Domains and Applications

Healthcare, Waste water Plant, Desalination Plant, Pollution control

Applications or Domain
  • Healthcare: Provides efficient steam-based sterilization of medical equipment. 
  • Desalination Plants: Enhances seawater desalination efficiency. 
  • Wastewater Treatment: Improves industrial and municipal wastewater management. 
  • Power Generation: Boosts steam generation efficiency in power plants.

Geography of IP

Type of IP

Application Number

202121056269

Filing Date
Grant Number

434993

Grant Date
Assignee(s)
Indian Institute of Technology Bombay