The impact of interface characteristics on the recyclability and repulpability of packaging material
(2022) KETM05 20222Chemical Engineering (M.Sc.Eng.)
- Abstract
- The world is slowly moving towards a more environmentally friendly mindset and many companies, such as Tetra Pak® have followed this lead by producing more environmentally friendly products and developing better materials with less environmental impact. To accommodate these requirements, it is important that the package is recyclable. For a carton this is defined by the repulpability, i.e., the ability of the material to disintegrate and the fibers to disperse.
Cartons consist of several layers containing different materials, such as plastics, cellulose and a barrier (that usually consists of aluminum foil). Together they give the package all of the wanted properties. The parts of the material that consists of fibers need to be... (More) - The world is slowly moving towards a more environmentally friendly mindset and many companies, such as Tetra Pak® have followed this lead by producing more environmentally friendly products and developing better materials with less environmental impact. To accommodate these requirements, it is important that the package is recyclable. For a carton this is defined by the repulpability, i.e., the ability of the material to disintegrate and the fibers to disperse.
Cartons consist of several layers containing different materials, such as plastics, cellulose and a barrier (that usually consists of aluminum foil). Together they give the package all of the wanted properties. The parts of the material that consists of fibers need to be separated from the polymers and aluminum during the repulping in order to be able to be repulped and thereafter further recycled. This thesis examines the method and repulpability and investigates the influence of interface characteristics on the recyclability of three materials, packaging material A, B and C (C has an aluminum barrier and A and B have fiber-based barriers). Different parameter settings, such as temperature, rotor speed, pre-soaking, moisture content and pH have also been investigated during the repulping process using the three forementioned materials.
The pulp was analyzed visually by making paper sheets out of the pulp, and quantitatively by doing further test on the pulp after the repulping to determine its quality. It was found that different parameters influenced the repulping time as well as the fiber flake content. The drainability was mostly influenced by the different properties of the materials, and the fibers in reject and flake content were influenced by both material properties and parameter settings.
Based on the results, a higher temperature than 43°C should be used when running the repulping trials, as it decreases the repulping time, and with it, energy consumption of the pulper. Material C gave the best recyclability out of the tested samples, and material A was the best alternative regarding the recyclability out of the two materials with fiber-based barriers. Material A would therefore be interesting to use for further research and development of recyclable material. (Less) - Popular Abstract
- Have you noticed that the food products you buy often are kept in packages that claim to be recyclable? But how recyclable are they actually?
Paper-based packages used as beverage containers consist of many different layers with different materials, paperboard, plastics and aluminum foil. The layers all have different functions and together protect the product from the outside environment and give the package its strength and rigidity. These material layers need to be separated from each other during the recycling process to facilitate the recycling of the individual materials. It is however very difficult to recycle beverage cartons, as specialized recycling mills are required, and not all of the specialized mills recycle all material... (More) - Have you noticed that the food products you buy often are kept in packages that claim to be recyclable? But how recyclable are they actually?
Paper-based packages used as beverage containers consist of many different layers with different materials, paperboard, plastics and aluminum foil. The layers all have different functions and together protect the product from the outside environment and give the package its strength and rigidity. These material layers need to be separated from each other during the recycling process to facilitate the recycling of the individual materials. It is however very difficult to recycle beverage cartons, as specialized recycling mills are required, and not all of the specialized mills recycle all material layers.
In 2019, 59.1% of all paper and paperboard consumed in the world was made from recycled material, 64.9% of the energy needed for on-site production was coming from renewable resources and 52.6% of the wood used for the pulp production came from sustainable-managed forests . However, the average recycling rate for beverage cartons was only 51% in in Europe in 2019 and 36.1% in Sweden in 2017.
The fibers in the packages are of great importance regarding the recyclability of beverage cartons as they can be recycled multiple times into other fiber-based products. Tetra Pak® is researching alternative material layers to increase the amount of fibers in their packages, and are especially looking to exchanging the aluminum layer with a fiber-based barrier. Three different packaging materials were studied in this thesis to see if the recyclability differs between material with fiber-based barriers compared to material with aluminum, and if the pulping environment can be changed to increase the recyclability.
The study showed that an increased temperature during the pulping increased the recyclability of the studied materials, and that all fibers in the material influence the recyclability and therefore need to be considered when constructing new materials. Out of the tested materials the aluminum material had the best recyclability, but one of the materials with fiber-based barrier seemed promising to work with and develop further.
Beverage cartons are recyclable, but more work needs to be done regarding the recycling process and in turn increase the packaging material recyclability. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9103979
- author
- Isacsson, Ingrid LU
- supervisor
- organization
- course
- KETM05 20222
- year
- 2022
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Tetra Pak ®, Recyclability, repulpability, packaging material, fiber-based barrier, chemical engineering
- language
- English
- id
- 9103979
- date added to LUP
- 2022-12-22 09:14:28
- date last changed
- 2022-12-22 09:14:28
@misc{9103979,
abstract = {{The world is slowly moving towards a more environmentally friendly mindset and many companies, such as Tetra Pak® have followed this lead by producing more environmentally friendly products and developing better materials with less environmental impact. To accommodate these requirements, it is important that the package is recyclable. For a carton this is defined by the repulpability, i.e., the ability of the material to disintegrate and the fibers to disperse.
Cartons consist of several layers containing different materials, such as plastics, cellulose and a barrier (that usually consists of aluminum foil). Together they give the package all of the wanted properties. The parts of the material that consists of fibers need to be separated from the polymers and aluminum during the repulping in order to be able to be repulped and thereafter further recycled. This thesis examines the method and repulpability and investigates the influence of interface characteristics on the recyclability of three materials, packaging material A, B and C (C has an aluminum barrier and A and B have fiber-based barriers). Different parameter settings, such as temperature, rotor speed, pre-soaking, moisture content and pH have also been investigated during the repulping process using the three forementioned materials.
The pulp was analyzed visually by making paper sheets out of the pulp, and quantitatively by doing further test on the pulp after the repulping to determine its quality. It was found that different parameters influenced the repulping time as well as the fiber flake content. The drainability was mostly influenced by the different properties of the materials, and the fibers in reject and flake content were influenced by both material properties and parameter settings.
Based on the results, a higher temperature than 43°C should be used when running the repulping trials, as it decreases the repulping time, and with it, energy consumption of the pulper. Material C gave the best recyclability out of the tested samples, and material A was the best alternative regarding the recyclability out of the two materials with fiber-based barriers. Material A would therefore be interesting to use for further research and development of recyclable material.}},
author = {{Isacsson, Ingrid}},
language = {{eng}},
note = {{Student Paper}},
title = {{The impact of interface characteristics on the recyclability and repulpability of packaging material}},
year = {{2022}},
}