From Science & Research
From Science & Research The AGRIMAX project Compostable seedbeds for the agricultural sector By: M.P. Villanueva, R&D Department AIMPLAS Paterna, Valencia (Spain) Steven Verstichel OWS Ghent, Belgium AGRIMAX is an EU-funded project that is developing and demonstrating the production of multiple, high-value products from crop and food-processing waste. The project is also developing economically competitive routes for marketing these products using flexible processing facilities that can be run by cooperatives. Around one third of all food produced each year is wasted and a significant proportion of this waste occurs at the field and food processing level. Globally, food and crop waste adds up to economic losses of around USD 936 billion a year and is responsible for 8 % of all global greenhouse gas emissions. In Europe alone, around 90 million tonnes of food and 700 million tonnes of crops are wasted every year. The four-year AGRIMAX project began in 2016 to address the following tasks: • The creation of two processing pilot plants (biorefineries), in Spain and Italy, for processing waste from cereals, olives, potatoes and tomatoes. • An online platform to coordinate waste supply and help maximize the use of the pilot plants throughout the year. • Processing technologies that produce high-value biobased compounds. • A biobased-compound performance test. • Regulatory assessments on the environment and society. • Cost-competitive marketing strategies. Thanks to the application of different processes in these waste streams, a series of new biobased compounds will be produced for application in: • Packaging (biopolymers, biocomposites, biocoatings, active packaging and stabilizing agents). • Food (additives, ingredients, natural flavouring substances, edible coatings and microbial growth media). • Materials for biodegradable agriculture, or plasticulture (seedbeds, mulch films and biofertilizers). End users will test the products to validate their profitability and performance. The remaining biomass will be used to produce biogas or enrich the soil. The Agrimax project is funded through the Biobased Industries Joint Undertaking (BBI) European initiative and the EU Research and Innovation Programme Horizon 2020, grant agreement no. 720719. Development of biodegradable and compostable biobased compounds Within the European Agrimax project, different compostable materials are being developed with the addition of fibre from agro-industrial waste. These newly Four new Agri-Value Chains from waste Tomato Olive Cereal Potato Figure 1. Flowchart of the AGRIMAX project. Online Platform Food Industry Waste Multifeedstock Biorefinery Biogas Cascade of High-value Bio-based Products Food Additives & Ingredients Materials for Agriculture BioFertilizers BioPackaging BioChemicals & Additive (including fibres) Co-operative Commercialisation 28 bioplastics MAGAZINE [04/20] Vol. 15
From Science & Research Figure 2. From waste to injection moulding of the material. Potato waste Potato fibres Bio-based compound Injected specimens developed compounds with fibre have been used to make plant pots and seedbeds through injection moulding. Although fibre increases the viscosity of the biopolymers used, the formulation of the material and the processing parameters have been optimized to achieve proper mould filling, thus reducing the friction of the material and its residence time in the equipment. AIMPLAS evaluated the processability of the new compounds by producing injection-moulded tensile bars (Figure 2) and then characterizing their mechanical and thermal properties (see Figure 3 and Figure 4). The results show that the mechanical and thermal resistance of the compounds with up to 15 % fibre was higher than the reference material (PP). The best biocompounds were selected for the production of plant pot prototypes. In terms of the surface area, dimensions and mechanical properties obtained so far, the materials produced are suitable for growing ornamental plants and seeds. Figure 5 shows some injection-moulded samples produced with compostable materials and waste potato fibre used as a filler. The pots demonstrated good compression resistance (1320 N at 15 % fibre) and drop impact resistance (no breakage when dropped from a height of two metres). Compostable seedbeds Although the materials used for developing the compounds are compostable and the fibre comes from agro-industrial waste, tests are currently being performed to check the compostability of the compounds containing fibre in accordance with European standard EN-13432, including the disintegration of the injection-moulded seedbeds. This standard defines four main requirements: a) determination of the chemical characteristics of the materials; b) biodegradability under controlled composting conditions in accordance with standard ISO 14855 c) determination of the degree of disintegration in accordance with the procedure established in standard ISO 16929 d) Assessment of the compost quality, including ecotoxicological effects on higher plants (OECD 208). After 4 weeks the disintegration of biocompounds with 15 % of potato fibre has clearly started (see Figure 7). The material felt brittle and was falling apart. These tests will determine if the waste seedbeds can be treated in a composting plant after use. Stress resistance http://agrimax-project.eu 32,2 12,3 28,1 28,9 26,6 Figure 5. Injection-moulded compostable plant pot prototypes obtained from potato fibre. Figure 6. Plant pots before and after compression test PP Biopolymer Compound 5% PF Compound 10% PF Compound 15% PF Figure 3. Stress resistance of new biocompounds Thermal resistance-HDT 91,7 87,4 89,7 93,1 73,3 PP Biopolymer Compound 5% PF Compound 10% PF Compound 15% PF Figure 4. Thermal resistance of new biocompounds Figure 7. Plant pots disintegration test: at start (left); after 4 weeks (right) bioplastics MAGAZINE [04/20] Vol. 15 29
