TURNING NON-RECYCLABLE MIXED PLASTIC FROM MUNICIPAL SOLID WASTE INTO VALUABLE CHEMICALS AND CARBON MATERIALS (VALORPLASTIC)

VALORPLASTIC

In the EU over 27.1 million tonnes of plastics are thrown away each year. Currently 69.9% of this goes to landfill (27.3%) or is incinerated (41.6%), causing major environmental problems. The project VALORPLASTIC will work on potential solutions to this problem. It will show municipalities how to achieve better recycling rates of plastic waste and create new circular economy business opportunities.

Particularly, VALORPLASTIC addresses the chemical recycling of currently dirty non-recyclable mixed plastic (NRMP) from municipal solid waste (MSW) which would otherwise have been bound for landfill or incineration. These plastic wastes (mainly polystyrene and polypropylene) will be converted into valuable chemicals (mainly light aromatic compounds) via chemical routes and separation steps. This multistage process will also yield carbon char as by-product, whilst it will present improved economic sustainability thanks to the valorization of carbon char as adsorbent for biogas from landfill treatment.

The technical aim of the project is therefore to develop a fully flexible, integrated pyrolysis technology to treat dirty NRMP from MSW to produce high value (i) chemicals (mainly light aromatic compounds) and (ii) carbon materials, through control of the waste pyrolysis process conditions and the use of novel catalysts.

By making NRMP from MSW valuable, it would encourage recycling and divert plastic from landfills. The challenge it to close the plastic recycling loop involving technologies/developments that can be exploited in plastic industry. Results of this project can be turned into an opportunity for the EU and the competitiveness of the European industry.

Graphical summary of the proposal process to the processing of dirty plastic from MSW

MAIN OBJETIVE

The overall objective of the proposed VALORPLASTIC project is to address the chemical recycling of a large fraction of today’s non-recyclable mixed plastics from municipal solid waste. First, the project combines chemical routes to produce valuable chemicals and second, it pretends evaluate the performance of carbon materials derived from obtained char in high value applications.

SPECIFIC OBJETIVES

Objective 1

Objective 2

Objective 3

Initial plastic feedstock testing

The researchers will receive approximately 2000-2500 kg of dirty non-recyclable mixed plastic from municipal solid which will be derived from Eco-Central Granada (a municipal solid waste treatment plant located in the south of Spain). 

Studying the two-stage pyrolysis of dirty non-recycled mixed plastics from municipal solid waste to its conversion into valuable chemicals

Experiments will be carried out in order to:

Screening properties of char byproduct

The char will be fully characterized in terms of physical (surface area, porosity, etc.) and chemical (pH, elemental analysis, ash composition, etc.) properties.

Objective 4

Objective 5

Upgrading properties of char for developing novel low-cost carbon materials through a unique set of functionalization protocols 

Submitting the crude chars to a sequential solvent extraction with organic solvents and upgrading of char by means of physical (with CO2 and/or steam) and/or chemical (with NH3, H3PO4, etc.) activation processes. Carbon materials will be further characterized and compared with raw chars and commercial activated carbons, in terms of physicochemical, structural and morphological features.

Evaluation of carbon materials in advanced applications as carbon adsorbents

Assessing of the performance of carbon materials by evaluating their capacity to remove CO2 from landfill gas stream at a lab-scale adsorption unit.

Graphical scheme of objetive 2

Graphical scheme of objetives 3, 4 and 5

WORKING PACKAGES (WP) + taskS

WP 1. Waste definition and characterization (Objective 1)

Task 1: Identification and quantification of plastics existing in MSW 

Evaluation of the composition and characteristics of the non-recyclable plastics (the feedstock of the project) containing in the municipal solid waste (fraction non-recovery selectively). A total of 100 kg of dirty non-recyclable plastics from municipal solid waste will be collected from Ecocentral Granada each week and this process will be repeated for 4 weeks in each station of the year. Identification and quantification of plastics existing in this fraction will be conducted following procedure described in the picture below.

Solid waste sampling will be carried out according to the random sampling method based on American Society of Testing and Materials (ASTM) standard. Then, identification of plastics will be performed by visual inspection, density, differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR).

Summary of procedure that will be performed to identify and quantify plastics existing in MSW. 

Task 2: Characterization of non-recyclable plastics existing in MSW.

The evaluation of the composition and characteristics of the non-recyclable plastics (the feedstock of the project) containing in the municipal solid waste (fraction non-recovery selectively). A total of 100 kg of dirty non-recyclable plastics from municipal solid waste will be collected from Ecocentral Granada each week and this process will be repeated for 4 weeks in each station of the year. Identification and quantification of plastics existing in this fraction will be conducted following procedure described in the picture.

Task 3: Estimation of the total amount of non-recyclable plastics existing in MSW.

This WP will also include the total amount of dirty non-recyclable plastics existing in MSW in Granada, Spain and Europe.

In this work package the researchers have the collaboration of José Manuel Soto Medina and Jorge Oliva Barrena. Both experts have a wide technical training and an extensive experience in supervision of important projects about solid waste management. They will facilitate the access to material and will provide data to perform estimations of Task 3.

Researchers WP1: G. Blázquez; M. Calero; M.A. Martín-Lara; PhD student.

Collaborators WP1: J.M. Soto; J. Oliva.

Deliverables WP1

D1. Input material definition and characterization technical report (one report for each season)

Milestones WP1

M1. Granada EcoCentral dirty non-recyclable mixed plastic fraction waste characterized.

M2. Estimation of the total amount of dirty non-recyclable mixed plastic fraction available in Granada, Spain and Europe.

WP 2. Pyrolysis Conversion Routes (Objectives 2 and 3)

Task 3: Preparation and characterization of catalysts

The different catalysts that will be studied in the project include: HY and HZSM-5 commercial zeolite catalysts and basic metal oxides such as CaO and MgO. 

First, a complete review of literature to design the best catalysts for upgrading oil from pyrolysis of plastic materials to a liquid product with higher content of light aromatic compounds will be carried out. Then, methods to modify catalysts for upgrading pyrolysis oil product towards the formation of valuable aromatic hydrocarbons will be performed. 

Task 4: Study the influence of pyrolysis and catalyst bed temperatures and type of catalysts on pyrolysis of currently non-recyclable plastic waste from municipal solid waste for the production of valuable chemicals.

Study of the catalytic performance of the resultant modified catalysts for the upgrading of oil product. The influence of temperature of both pyrolysis and catalytic reactor and types of catalyst on the pyrolysis-catalytic upgrading of waste plastics for valuable chemical production will be investigated. To improve the relevance of the project, the sample of plastic used will be real (provided by Ecocentral Granada) and according to the composition of non-recyclable plastics of municipal solid waste determined in work package 1.

Schematic diagram of the two-stage pyrolysis-catalytic fixed bed reactor system

Task 5: Assessing the effect of the operating conditions on the yield and composition of the gas

The pyrolysis process also produces a clean, high calorific value gas. The non-condensable gases will be analyzed immediately after each experiment using gas chromatography. Hydrocarbon gases from C1 to C4 will ve analyzed by gas chromatography equipment with flame ionization detector (FID). Permanent gases will be analyzed using other gas chromatography equipment with a thermal conductivity detector (TCD).

Task 6: Assessing the effect of the operating conditions on the yield and properties of the produced chars

Chars will be produced as by-product from the pyrolysis of different dirty non-recyclable mixed plastic waste.

The following characterization tests will be performed to chars:

Researchers WP2: G. Blázquez; M. Calero; M.A. Martín-Lara; A. Pérez; PhD student.

Collaborator WP2: F. Carrasco-Marín; L. Quesada

Deliverables WP2

D2. Catalysts preparation and characterization report.

D3. Impact of experimental conditions and type of catalyst used in pyrolysis process on the production of valuable chemicals report.

D4. Impact of experimental conditions and type of catalyst used in pyrolysis process on the composition of gas effluent.

D5. Impact of experimental conditions and type of catalyst used in pyrolysis process on the yield and properties of char.

Milestones WP2

M3. Control point to evaluate the appropriateness of developed catalyst to be employed in Task 4.

M4. Control point to evaluate the yield and composition of liquid oils to be employed chemical feedstock (source of light aromatic compounds).

M5. Control point to evaluate the characteristic of gas effluent to be employed as fuel or chemical feedstock.

M6. Control point to evaluate the appropriateness of produced chars to be employed in Task 7 based on their physicochemical properties.

WP 3. Refining of chars (Objective 4)

Task 7: Development of low-cost carbon materials for high-value applications.

Char is as a promising precursor of advanced carbon materials. Generally, the pyrolytic char does not possess properties of sufficiently high quality to be directly reused owing to the presence of oils and contaminants. First a sequential solvent extraction (with hexane and acetone) to remove and recover the pyrolysis liquid products trapped in the raw chars will be carried out. Then, an activation process is needed to expand the char specific surface area and porosity. This will be carried out through physical and chemical activation.

Task 8: Physic-chemical characterization of produced carbon materials.

For this Task will be employed the same characterization techniques as those used with raw chars to study their compositional and structural properties in comparison with raw chars. Besides, commercial activated carbons will be purchased to compare their features with the raw and upgraded char-based materials.

Researchers WP3: M. Calero; M.A. Martín-Lara; A. Pérez; PhD student.

Collaborator WP3: F. Carrasco-Marín

Deliverable WP3

D6. Report about the impact of activation methods used in the development of low-cost carbon materials on the properties of upgrading-char.

Milestone WP3

M7. Control point to evaluate the appropriateness of upgraded-chars to be employed in WP4 based on their enhanced physicochemical and structural properties.

WP 4. Application of carbon materials in the upgrading of landfill gas (Objective 5)

Task 8: Installation of the lab-scale adsorption unit.

Purchasing and supply of components: tubing, fittings, valves, mass flow controllers, reactor, gas analyzer (CO2, CH4) and gas standards (to achieve an average composition of landfill gas) for the analyzer calibration and carbon materials performance testing. Assembling the adsorption unit and testing it searching for leaks and potential operational problems according to health and safety procedures and protocols.

Task 9: Screening of the upgrading-chars.

This task will be focused on the removal of CO2 from landfill gas as a fundamental step in biogas treatment to biomethane.

Evaluation of the performance of the carbon materials (upgraded-chars) to upgrade landfill gas will be performed. Particularly, the evaluation of the CO2 capture capacity of the prepared chars by circulating a landfill gas stream through the adsorption unit and monitoring the treated gas composition at the outlet of the unit on a continuous way for 2-4 h will be completed. 

Researchers are partners of LIFE LANDFILL BIOFUEL. This task will be performed in collaboration with Jorge Oliva, responsible of the biogas plant linked to EcoCentral landfilling. 

Researchers WP4: M. Calero; M.A. Martín-Lara; A. Pérez; PhD student.

Collaborator WP4: J. Oliva.

Deliverables WP4

D7. Lab-scale adsorption unit installed.

D8. Technical report including the performance of the adsorption unit to upgrade landfill gas.

Milestones WP4

M8. Control point to evaluate the correct lab-scale adsorption unit construction and its proper installation that will allow the next phase of the work to begin.

M9. Control point to evaluate the appropriateness of adsorption unit performance with the upgraded chars (based on their CO2 adsorption capacity, kinetics, among other parameters).

WP 5. Environmental impact of the project through a Life Cycle Analysis (LCA) using the SimaPro software

Task 10: Life cycle assessment.

The main objective of this work package is analyzing environmental impacts associated with all the stages of the process. A life cycle assessment will be performed using SimaPro software. SimaPro is the most widely used LCA software. It offers standardization and used of the world’s leading databases.

The life cycle assessment (LCA) presents in this study will quantify the total energy requirements, energy sources, atmospheric pollutants, waterborne pollutants, and solid waste resulting from the production of high-value chemicals and carbon materials from non-recyclable plastic waste (low quality plastic waste). 

Also, improvement in environmental and climate performance (reduction of greenhouse gas emissions, improvement of water quality, etc.), use of natural resources (reduction of raw materials, reduction of energy consumption, etc.), land use, agriculture and forestry (areas of agricultural land under sustainable management, etc.), biodiversity, between others, will be quantified in terms of change compared to the initial situation.

Researchers WP5: M. Calero; M.A. Martín-Lara; PhD student.

Collaborator WP5: G. García-García

Deliverable WP5

D9. LCA report.

Milestone WP5

M10. Final indicators collected and quantification of environmental impact.

M11. LCA completed.

WP 6. IPR protection, dissemination and communication

Task 11: IPR protection and exploitation of results

The state-of-the-art and patents will be permanently updated to verify that, if necessary, our results can be freely exploited. If so, the UGR will support the researchers in the process of patent filing.

Task 12: Dissemination

The researchers of the project will attend several conferences, workshops and intersectoral events. Their contribution with oral communications will help to increase his visibility among experts in the field, opening up the opportunity for new collaborations. Preparation and submission of manuscripts to international open access peer-reviewed scientific journals. 

Task 13: Communication

The scope, objectives and key findings of VALORPLASTIC will be communicated to the general public using accessible language. These aims to raise awareness of the potential impact of the action engage society and gain a long-term visibility of the project. Our main target audience will be young people, who may feel engaged about pursuing a research career and get more involved in outreach activities (for example, European Researcher´s Night). The researchers of the project will also promote the “National Programme for Research Aimed at the Challenges of Society from the Spanish Ministry of Science, Innovation and Universities” by contributing to local newspapers and voluntary lectures at schools and universities. 

Researchers WP6: All.

Collaborators WP6: All

Deliverables WP6

D10. Dissemination in UGR website and other informal communication events.

D11. Publication in peer-reviewed international journals.

D12. Presentation of the results as conference communications.

D13. Organization of one workshop event.

D14. Contracts with companies.

Milestone WP6

M12. Evaluation of the activities carried out each year of the project and their impact and actual outcomes using qualitative and quantitative indicators. Identification of any possible deviation to be corrected for the following years of the project.