How Industrial Paper and Cardboard Recycling Is Reducing the Energy Footprint in Manufacturing Processes

Producing new paper from raw wood pulp can consume up to 40% more energy than recycling existing paper products. This heavy energy demand, coupled with deforestation and high greenhouse gas emissions, poses a serious challenge for industrial sustainability. At the same time, rising material costs and supply chain disruptions have made traditional paper production less viable. This is why, in response to these challenges, many industries are increasingly recognising the benefits of recycling paper and cardboard and adopting circular economy models and sustainable technologies.

This article explores the impact of waste paper and cardboard on the environment and the modern recycling technologies that are transforming industrial sustainability while reducing the carbon & energy footprint in manufacturing.

Understanding the Energy Footprint of Waste Paper and Cardboard in the Manufacturing Industry

The paper and cardboard industry is a major energy consumer, with Australia generating 5.76 million tonnes of scrap paper and cardboard in 2020–21—about 224 kilograms per person.

Energy Requirements of Traditional Recycling Methods

  • Recycling one ton of paper using traditional methods requires 4,000 kWh of energy—enough to power an average home for six months.
  • Water-intensive processes consume between 7,000–50,000 gallons of water per ton, depending on the type of paper.
  • The deinking and re-pulping stages require large amounts of electricity and chemical treatments, further increasing the energy footprint.

On the other hand, producing paper from recovered materials uses 55% less water while cutting air pollution by 74% and water pollution by 35%. These reductions help mitigate industrial emissions and conserve resources.

Recycling just one tonne of paper and cardboard has substantial benefits: it saves 12 trees, 2.5 barrels of oil, 4,100 kilowatt-hours of electricity, four cubic meters of landfill space, and 31,370 liters of water. These figures underscore the importance of efficient recycling systems in lowering the energy footprint of the manufacturing industry.

Modern Paper and Cardboard Recycling Techniques Reducing Carbon Footprints

The paper and cardboard recycling industry is adopting advanced techniques to minimise carbon emissions at every stage of the waste paper recycling process. Here are the key modern techniques:

Energy-Efficient Deinking Technology

Deinking is the process of removing ink, adhesives, and coatings from recycled paper to produce high-quality pulp. Modern industrial waste recycling types ensure that materials are processed efficiently.

Froth Flotation Deinking
Froth flotation deinking is a process where air bubbles lift ink and other impurities to the surface, allowing them to be skimmed off. It involves adding surfactants to create fine bubbles that attract ink particles. The ink-laden bubbles rise to the surface, leaving behind cleaner paper fibers.

Eco-Friendly Surfactants
Eco-friendly surfactants are biodegradable chemicals that help separate ink and coatings from recycled paper fibers. Unlike traditional surfactants, which can contribute to water pollution, these alternatives easily loosen ink particles. By using plant-based or biodegradable surfactants, industrial recycling plants can maintain high drinking performance while minimising harm to aquatic ecosystems and reducing chemical waste.

High-Efficiency Pulping

Pulping is the process of breaking down recycled paper and cardboard into fibers, which can be reused in the production of new paper products. Traditional pulping methods often damage fibers or require high energy input.

Low-Consistency (LC) Pulping
Low-consistency (LC) pulping is a method where the fiber-to-water ratio remains low, typically around 3-5%. It utilizes a rotor to generate turbulence, gently breaking down fibers without significantly degrading them. This method requires less energy than high-consistency pulping.

Drum Pulpers
Drum pulpers are large, rotating cylindrical machines that continuously process waste paper into pulp. They work by gently tumbling paper with water, allowing fibers to separate while minimising mechanical damage. It is particularly effective for mixed waste paper because it helps remove contaminants such as plastic, staples, and adhesives.

Enzyme-Based Pulping
This process is closely linked to organic recycling as it harnesses natural biological components to enhance sustainability. This pulping technique utilises biological catalysts to break down cellulose fibers in recycled paper. Unlike traditional chemical pulping, which relies on harsh substances, this method introduces specific enzymes that weaken the fiber bonds, making separation easier.

Low-Carbon Drying

Drying recycled pulp is one of the most energy-intensive stages in paper production. Some low-carbon drying technologies are:

Infrared (IR) Drying
Infrared (IR) drying uses infrared radiation to directly heat and evaporate moisture from recycled paper pulp. IR drying systems consist of specialised emitters that generate shortwave or medium-wave radiation, which penetrates the pulp and removes water quickly. Additionally, IR drying provides precise temperature control, preventing fiber damage and improving the overall quality of recycled paper products.

Superheated Steam Drying
Superheated steam drying involves using high-temperature steam to remove moisture from paper pulp efficiently. This consists of a closed chamber where steam, heated above its boiling point, rapidly evaporates method water from the pulp.

Heat Recovery Systems
Heat recovery systems capture and reuse excess heat generated during the paper and cardboard recycling process. These systems consist of heat exchangers, condensers, and thermal storage units that collect waste heat from dryers, pulpers, and boilers. The recovered heat is then redirected to preheat incoming materials or water, decreasing greenhouse gas emissions while maintaining high productivity.

Advanced Water Recycling Systems

Water is essential in paper and cardboard recycling, but excessive use leads to resource depletion and wastewater pollution. Proper industrial waste management solutions, such as advanced water recycling systems, help mitigate these challenges.

Membrane Filtration Systems
Membrane filtration systems use fine-pore membranes to separate contaminants from wastewater, allowing clean water to be reused in the waste paper recycling process. These consist of microfiltration, ultrafiltration, and reverse osmosis membranes that remove suspended particles, ink residues, and dissolved chemicals. It ensures a more efficient and sustainable recycling process while reducing pollution and operational costs in paper mills.

Closed-loop Water Systems
Closed-loop water systems recycle and reuse water within the paper recycling plant, preventing wastewater from being discharged into the environment. It includes filtration, chemical treatment, and sedimentation processes that remove impurities, allowing the same water to be used multiple times.

Zero Liquid Discharge (ZLD) Technology
Zero liquid discharge (ZLD) technology ensures that no wastewater is released from a recycling plant by completely recovering and treating water. The evaporators, crystallisers, and filtration units in it remove impurities, leaving behind solid waste while recovering purified water for reuse.

Carbon Capture and Utilization (CCU) in Paper Mills

Carbon capture and utilisation (CCU) technologies help paper mills reduce their greenhouse gas emissions by capturing CO₂ and repurposing it for useful applications.

CO₂ Capture Systems
CO₂ capture systems trap carbon dioxide emissions from paper and cardboard recycling plant chimneys before they enter the atmosphere. These systems consist of chemical absorption units, membranes, and storage tanks that collect and concentrate CO₂. The captured gas can then be stored underground or repurposed for industrial use.

Algae-Based Carbon Capture
Algae-based carbon capture uses microalgae to absorb CO₂ emissions from paper mills. These algae grow in bioreactors or open ponds, converting CO₂ into oxygen and biomass. The harvested algae can be processed into biofuels, fertilisers, or animal feed.

Carbon Utilization for Chemicals
Carbon utilisation for chemicals involves converting captured CO₂ into useful chemical compounds such as methanol, carbonates, and synthetic fuels. These processes use catalysts and biochemical reactions to transform CO₂ into industrial products, reducing dependence on fossil fuels.

An Overview of Modern Recycling Techniques & Carbon Footprint Reduction Impact

 

TechnologyHow It Helps Reduce Carbon Footprint
High-Efficiency PulpingReduces energy and water usage, minimising emissions from pulping processes.
Energy-Efficient DeinkingLowers chemical dependency and prevents harmful waste discharge.
Advanced Water RecyclingReduces fresh water demand, preventing water wastage and pollution.
Low-Carbon Drying TechnologyMinimises fuel consumption during drying, reducing energy waste.
Carbon Capture & Utilization (CCU)Captures CO₂ before it is released, preventing emissions from reaching the atmosphere.

Wrapping Up!

Recycling is essential for a sustainable future, and paper and cardboard are among the most valuable materials to recover. But managing these different waste paper and cardboards effectively takes the right equipment, expertise, and a solid understanding of the recycling process.

At OGTEC, we have a proven track record of designing, manufacturing, and installing high-efficiency recycling plants throughout Australia, helping businesses optimize material recovery while achieving strong returns on investment. Whether you want advanced plant and cardboard recycling or skip bin recycling solutions, get in touch with us today!

Leave a comment

Your email address will not be published. Required fields are marked *