Papers cardboards axis

Excerpt

The research focuses on the different outgoing flows from paper and cardboard recycling plants: recycled fibers (known as accepted fibers), liquid rejects and solid rejects, and aims to develop new, more sustainable recycling or recovery processes for each.

For the accepted fraction, the aim is to improve inter-fiber bonds in the dry state, while maintaining repulping properties. The aim of this improvement is to limit the use of additives and thus minimize the associated costs and rejects.

For the liquid waste fraction, the aim is to develop a biorefinery integrated into a recycling unit. The starch present in used cardboard, which accumulates in the process water during recycling, is eliminated to avoid clogging the circuits, but is not currently recovered. The extraction and recovery of these compounds, in polymer or monomer form, could be applied to “secondary” biomass.

For the solid fraction, the aim is to develop alternatives to current recovery methods that are better adapted to the mixtures and conditions of the materials. The production of microfibrillated cellulose (reinforcement, rheological agent), regenerated cellulose (aerogels) or cross-linked cellulose (resins) is envisaged to take advantage of the damaged state of lignocellulosic fibers. For plastic-intensive waste, other thermoconversion routes are being considered to improve energy yields and diversify co-products.

The socio-environmental and economic impacts of all these flows will be studied.

Key words: Paper-Cardboard, Packaging, Lignocellulosic fibers, Recycling, Recovery, Biorefinery, Physicochemical separation, Upcycling, Green chemical processes, Enzymatic processes, Thermoconversion, Life cycle assessment, Best Available Technique, Innovative ecosystem.

Tasks

Our researchers

Upcycling of the accepted fiber fraction from cardboard recycling and recovery of fibrous rejects
nathalie.marlin@grenoble-inp.fr

• Reinforce the mechanical properties of recycled paper without adding starch, while retaining its repulping properties.
• Enhance the value of fibrous waste by taking advantage of its morphological state

Development of a new type of biorefinery from “urban forests”: recovered paper and cardboard
christine.chirat@grenoble-inp.fr

Extract starch from cardboard during recycling, and recover it to avoid its accumulation in process water

Cellulose and carbon aerogels
romain.sescousse@mines-albi.fr

Adding value to fibrous waste: producing porous materials

Recovering complex, non-recyclable fibrous waste by thermal methods
marion.carrier@mines-albi.fr

Propose efficient thermoconversion processes

Environmental and economic impact of new processes and materials developed
valerie.laforest@emse.fr

Report on the impact of new processes and products on the local ecosystem

Excerpt

The DEFI2R project aims to offer new technical solutions to paper and cardboard recycling operators by demonstrating the possibility of using green chemical and biological decontamination processes to produce food packaging and hygiene paper from contaminated raw materials. In addition, the project will aim to recover fiber waste, a co-product that is not yet recovered by recycling plants, to form insulating or structural panels for the construction sector.

To this end, research will focus on combining specific enzymes and ozone to eliminate chemical contaminants and microorganisms present in recycled fibers, as well as on 3D printing and a foaming process based on the use of fibrous waste, mixed or not with recycled fibers, to form high-performance panels. DEFI2R will be able to build on the Phase I project, PAC3R, and its researchers to further advance the recovery of fibers and fibrous waste from recycling.

Key words: Paper and board recycling ; cellulosic fibers ; fibrous rejects ; decontamination processes ; biocatalysis ; ozonation ; 3D-printing ; wet foam ; food packaging ; hygiene papers ; life cycle assessment

Tasks

Our researchers

Identification, selection, and analysis of accepted fibers and fiber rejects, as well as their contaminants
Rénato Froidevaux (BioEcoAgro)
Yassine Makni (Anses)

• Literature review on the nature of chemical and biological contaminants found in recycled paper and cardboard
  This task will provide partners working on decontamination with a comprehensive list of chemical and biological contaminants that can be found in paper and cardboard, based on scientific articles on the subject and current regulations concerning, among other things, food packaging and hygiene paper.
• Analysis of accepted fibers and industrial fiber waste, as well as a panel of contaminants for each substrate studied
  A shorter list of contaminants selected for their occurrence, hazardousness, and persistence in the environment will be compiled from the comprehensive list produced in the first task. The contaminants will be sought in several industrial substrates by GC-MS and LC-MS. FTIR and Raman spectroscopy analyses will complement these initial results. BioEcoAgro will identify certain microorganisms present in industrial fibers. At the same time, high-resolution chromatography will be used by ANSES to analyze all contaminants present.
• Development and sharing of analytical method protocols within the consortium
  Analytical tools concerning the toxicity of contaminants and their degradation products, their migration into food, and microbial testing will be developed by BioEcoAgro and ANSES based on methods already known to these partners and recent literature. Protocols for extraction and analysis by GC-MS and LC-MS of contaminants in fibers will also be harmonized between partners.

Decontamination of accepted fibers
Rénato Froidevaux (BioEcoAgro)
Etienne Montet (ECLORE)

• Elimination of chemical contaminants by enzymatic and oxidative means
  In these two tasks, decontamination processes using enzymes or chemical oxidants (ozone, H2O2, etc.) will be developed in order to eliminate chemical contaminants from recycled paper and cardboard. The extent of decontamination will be assessed by GC-MS and/or LC-MS. Their cytotoxicity will be measured by testing skin cells (Hacat) and intestinal cells (Caco 2).
• Elimination of biological contaminants by oxidation
  It is expected that lower doses of oxidants than those used in the previous task should be able to eliminate biological contaminants present in the fibers that could pose a problem for subsequent food contact. Microbial and migration tests will be used to evaluate sanitization. Particular attention will be paid to the presence of spore-forming microbes that can resist oxidation.
• Optimization of decontamination processes combining chemical oxidants and enzymes
  Enzymatic and chemical decontamination processes will be combined in series and then in a one-pot, two-step process. A strategy of immobilizing enzymes on hydrophobic supports could allow the enzymes to survive under oxidizing conditions and thus enable the use of a one-pot, one-step system. The parameters of the final decontamination process will be optimized to enable sufficient decontamination while preserving as much as possible the paper properties of the fibers, as evaluated in the following task.

Development and production of panels using 3D printing and foam insulation panels from fiber waste
Davide Beneventi (LGP2)
Cécile Sillard (LGP2)

• Development and characterization of materials obtained by 3D printing
  Formulation of composite pastes for 3D printing from fibrous waste. The study will begin with model compounds. Mechanical and rheological characterizations will be carried out on the composites in both wet and dry states. Various additives (starch, rosin, etc.) will be considered to improve the formulations. Decontaminated samples from Lot No. 2 will be used, as oxidation may have a positive effect on the 3D printing process developed in this task.
• Development and characterization of insulating foams
  Formulation of foams from fibrous waste. Model compounds will be used initially. The stability of the foam and its drying behavior will be studied, as these are the two critical parameters identified concerning the properties of the insulating panels formed. Samples decontaminated by oxidation in Lot No. 2 will be used in this task.
• Optimization and scaling up of 3D printing and foaming processes
  The aim of this task is to optimize the 3D printing and foam drainage parameters for the best formulations established in T3.1. and T3.2. in order to anticipate scaling up. Digital and robotic tools will be developed to produce series of structural panels using 3D printing. A prototype “sandwich” panel will be produced by combining an insulating panel with two structural panels created using the two processes developed in Lot No. 3.

Evaluation of technical and environmental performance
Etienne Montet (ECLORE)
Davide Beneventi (LGP2)

• Technical evaluation of the decontamination processes developed
  This task will evaluate the integrability of the decontamination processes for Lot No. 2 into a recycling line, as well as their effect on 3D printing and foaming processes that recover fiber waste and other low-value-added co-products. In particular, the effectiveness of decontamination and its impact on the mechanical properties of long fibers will be discussed. An estimate of the cost of decontamination will be made.
• Assessment of the environmental impact of the processes
  The effluents generated by the decontamination studied in Lot No. 2 will be analyzed by ANSES, as they will have to be treated in the recycling plant’s wastewater treatment plant if the process is to be used industrially. In addition, the recyclability of the 3D and foam panels in Lot No. 3 will be assessed. Finally, a Life Cycle Assessment (LCA) will be conducted, taking advantage of the workshops that will be held on this topic with the other areas of focus of the PEPR Recycling program.