Author: Katarzyna Jurkowska

One of the products of the anaerobic digestion process is digestate which can be used in agriculture. The use of digestate from anaerobic digestion in agriculture promotes sustainable farming practices, improves soil health, and enhances crop productivity while offering economic and environmental benefits. By recycling nutrients and organic matter, it helps create a more circular and sustainable agricultural system. The quality of digestate from anaerobic digestion is important for ensuring its effectiveness as a fertilizer, protecting the environment, safeguarding human and animal health and maintaining public trust. High-quality digestate maximizes the benefits of anaerobic digestion and contributes to sustainable agricultural practices. The quality requirements for digestate from anaerobic digestion can encompass nutrient content, pathogen reduction, contaminant levels, pH and salinity, moisture content, odour, and appearance. Adherence to these requirements ensures that digestate is safe and effective for agricultural use, promoting soil health and crop productivity while minimizing environmental risks.

In the framework of the LIFE BIOBEST project, ‘Guideline to promote quality compost and digestate’ was published. The guideline provides insights about the processing options (composting, anaerobic digestion), analysis of product characteristics (compost, digestate), quality assurance systems and the quality assurance scheme of the European Compost Network (ECN-QAS). The guideline aims to support upper-level authorities in streamlining policy measures and lower-level authorities in implementing effective solutions. The guidelines can serve as crucial resources for municipalities, policymakers, waste hauliers, recycling entities, and technical practitioners. It can help stakeholders in different stages of bio-waste implementation in planning and managing bio-waste and digestate.

Biogas production has many benefits. One of these is the production of digestate, which can provide a very good solution for agriculture as a fertiliser of natural origin.

Recently, the European Biogas Association (EBA) published a white paper analysing the potential of digestate in supporting healthy soils and promoting sustainable agricultural practices across Europe.

The report “Discovering the Contribution of Ferment to Healthy Soils”, looks at the benefits of the use of fermentation in the agricultural practices of EU countries – from reducing the need for costly artificial fertilisers to promoting effective and efficient soil management and productivity.

The production and use of digestate also fits in with the direction of changes taking place in EU policy on carbon farming and the transition to a greener and more sustainable agricultural sector.

The development of biogas and biomethane production in Europe will contribute to the production of increasing amounts of digestate, which should be managed accordingly. The utilisation of the digestate will benefit farmers, local communities and producers as well as the environment.

On 11 March 2024, another study visit took place as part of the project ‘Green transformation in practice: demonstration and dissemination of the benefits of biogas production from bio-waste’, implemented by the Institute of Environmental Protection-National Research Institute (IOŚ-PIB) and Vista Analyse. This time, representatives of IOŚ-PIB and the Water and Sewage Management Plant in Tomaszów Mazowiecki visited the Water and Sewage Company in Jarocin.

During the visit, representatives of the Water and Sewage Company in Jarocin and KREVOX, which was responsible for the design of the modernisation of the sewage treatment plant, discussed the entire process from the design to the implementation of the investment.

The modernisation included installations for biogas production and the generation of energy (electricity and heat) for the plant’s needs, as well as a phosphorus recovery installation; recovered phosphorus can be used for the production of fertilisers. As a result of these investments, the sewage treatment plant, which has a capacity of over 90,000 person equivalents, can cover its thermal energy needs entirely and, in the case of electricity, approximately 60%.

Modernising of the wastewater treatment plant in Jarocin sets an example for other municipal sewage treatment plants in the country regarding the direction of investments in green transformation.

On March 4-6, 2024, as part of the project “Green transformation in practice: demonstration and dissemination of the benefits of biogas production from bio-waste” implemented jointly by the Institute of Environmental Protection-National Research Institute (IOŚ-PIB) and Vista Analyse, a study visit to Norway was held. The visit was attended by representatives of the Polish partner IOŚ-PIB, the Tomaszów Mazowiecki City Hall and the Water and Sewage Management Plant in Tomaszów Mazowiecki.

During the first day of the visit, participants discussed the project’s progress and attended a presentation by the Biogas Norge association. Biogas Norge brings together companies and organizations involved in developing the biogas market in Norway. Its members represent the entire biogas value chain, from suppliers and producers to distributors and end users.

On the second day, participants visited a sewage treatment plant and its biogas plant belonging to the municipalities of Oslo, Bærum and Asker. VEAS, the largest sewage treatment plant in Norway, has a capacity of over 800 thousand person equivalents, treating approximately 100 million m³ of sewage annually. From the resulting sludge, the plant produces 40,000 tons of biofertilizer, 60 GWh of biogas, and 5 thousand tons of ammonium sulfate. The produced biogas undergoes refining and liquefaction into biofuel (bio-LNG) at the refinery. The third day focused on discussions regarding the preliminary feasibility study, a key outcome of the project, and the catalogs of good practices. In the latter part of the day, a representative from Biogass Oslofjord presented the local conditions of biogas production and utilization in the Oslo Fjord area.