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Systemic large scale eco-innovation to advance circular economy and mineral recovery from organic waste in Europe

Periodic Reporting for period 3 - SYSTEMIC (Systemic large scale eco-innovation to advance circular economy and mineral recovery from organic waste in Europe)

Reporting period: 2020-06-01 to 2021-11-30

The H2020 project SYSTEMIC started in 2017 with the aim of identifying innovative approaches to recover and recycle nutrients and organic matter from biowaste, manure and sewage sludge into new fertilisers and soil improvers and to integrate them optimally into a circular economy. Recovering and reusing nutrients including nitrogen (N), phosphorus (P) and potassium (K) from biowaste is a crucial component of a circular economy and will contribute to Europe’s transition to a carbon neutral economy.

The greatest nutrient streams are available in areas of concentrated livestock production, through manure and residues from agri-food industry, and in urban areas, in sewage sludge and municipal biowaste. Animal manure is mostly used as a fertiliser but in nitrate-vulnerable-zones (NVZs), its application is limited by the 170 kg N/ha limit set in the Nitrates Directive (91/676). Current disposal practices for surpluses of manure are unsustainable as manure is either transported over large distances, incinerated or biologically treated to remove nitrogen. Other nutrient-rich waste streams are yet disposed of through f.e. incineration meaning losses of nutrients.
SYSTEMIC demonstrated promising technologies for nutrient recovery and reuse in five demonstration plants. The main objective was to showcase that the combination of anaerobic digestion and nutrient recovery is a viable approach for the valorisation of biowaste.

The project successfully implemented different cascades of nutrient recovery at the demonstration plants. Its main conclusion is that nutrient recovery is technologically feasible but that its economic benefits depend on regional circumstances such as the supply and demand for nutrients. Generally speaking, nutrient recovery is economically feasible in regions with nutrient surpluses whereas the use of raw digestate is cheaper in regions with low livestock numbers and a demand for organic fertilizers. Emissions of nutrients and greenhouse gases slightly decrease or remain similar to the reference situation in which fields are fertilized by raw digestate and synthetic fertilizers. Overall, regional conditions (e.g. supply and demand for nutrients, vulnerability of soils for nutrient leaching, environmental targets etc.) shall be leading in selecting optimal treatment plans for digestate.
The project started with the implementation, monitoring and evaluation of full-scale technologies for nutrient recovery and reuse at five demonstration plants:

• Groot Zevert Vergisting (Netherlands) where digestate of pig manure and residues from agro-industry are processed into a mineral N fertiliser, organic soil improver and a P fertiliser.
• Am-Power (Belgium) where digestate of biowaste is processed into a dried organic P fertiliser, an liquid organic NPK fertiliser and clean water. They thereby reduce the volume the of the end products which in turn reduces costs and impact related to transport.
• Benas (Germany) where energy crops and poultry litter are used to produce biogas and electricity. In addition, mineral N is recovered and organic fibres are extracted and prepared for use in production of carton products.
• Waterleau New Energy (Belgium) where biowaste and pig manure are co-digested and processed into ammonium water and solid organic fertilisers.
• Aqua&Sole (Italy) were sewage sludge serves as a save raw material for the production of organic and mineral fertilisers.

The five demonstration plants were thoroughly monitored by the project team. Phosphorus is mostly recovered in solid fractions and, in GZV, in the form of a phosphate precipitate. Nitrogen is recovered in mineral form through stripping or membrane filtration. Nitrogen strippers, evaporators and dryers consume large amounts of thermal energy. For this, the biogas plants use waste heat that is released during the conversion of biogas to electricity showing the synergy between biogas production and nutrient recovery. Demonstration plants that sell biogas to the grid selected other technologies running on electricity rather than on thermal heat. Overall, it is concluded that the optimal technological solution strongly depends on the type of feedstock, the required composition of end products and the on-site availability of waste heat or electricity.
Biobased mineral N fertilisers (including RENURE fertilisers, e.g. Recovered Nitrogen from manURE) can effectively replace synthetic counterparts without increasing risks for nitrate leaching and are therefore a safe option for NVZs. Levels of heavy metals were generally low and do not possess environmental risks. Screening on residues of herbicides, pesticides and antibiotics revealed that such residues are present in digestate in organic fertilising products but absent in purified water (after reverse osmosis) and mineral N fertilisers. Overall, biobased fertilising products can safely replace raw manure and/or synthetic fertilisers.
Life-cycle analyses showed that nutrient recovery has a small positive effect on the overall carbon footprint of the demonstration plants as compared to the reference scenario in which digestate was used as fertilising product. Production of green energy is far more relevant in terms of CO2 savings as compared to the production of biobased fertilising products. The five demonstration plants were all located in regions with a surplus of nutrients from intensive livestock farming and digestate disposal was a cost item. Nutrient recovery lowers the costs for digestate disposal.
SYSTEMIC explored opportunities for ten other biogas plants interested in nutrient recovery. Several workshops and plant visits were organised. A business development package called the NUTRICAS tool has been developed which is available via www.systemicproject.eu.
SYSTEMIC demonstrated novel technical approaches to convert digestate into biobased fertilising products. Beyond the state of art were, in particular, the demonstration of a full scale installation to recover phosphorus as a calciumphosphate salt (GZV), the production of organic fibres for use in potting soil or for production of carton products (BENAS, GZV) and the nitrogen absorber using gypsum (a waste product) to bind ammonium rather than sulphuric acid (BENAS).

Further impact of the project will be generated through dissemination of the projects outcomes to industry and policy makers. In particular, the NUTRICAS tool is expected to be used after the end of the project.
Although the physical production of biobased products from organic waste streams is technically feasible, additional incentives are needed for a broad market introduction. Generally speaking, biobased products are not cheaper compared to synthetic fertilisers due to the high-tech technologies required to recover valuable nutrients out of complex organic waste streams, an unequal economic playing field and legal barriers hindering marketing, and a degree of end-user reluctance towards these unfamiliar new products.

The SYSTEMIC project team has written policy briefs with recommendations to speed up the transition towards a circular economy by improving acceptance of biobased fertilisers, financial profits for producers, and increasing possibilities for trading biobased fertilisers with an EC label. The recommendations are related to RENURE fertilisers, the new Fertiliser Product Regulation (FPR, 2019/1009) and the Emission Trading System which is part of the proposal Fit for 55.
SYSTEMIC Circular Economy Approach