We need a new circular legislation for sustainable sludge handling
EU rules “Directive 86/278” aim to ensure that the use of sewage sludge in farming does not harm the environment, animals and humans. The Directive, adopted 30 years ago, no longer matches current needs and expectations, such as properly regulating pollutants found in sludge. EasyMining welcomes the initiative from the EU commission to make a new circular legislation for sustainable sludge handling.
25 Nov 2020– The new legislation needs to ensure resource efficient and non-toxic recycling. Sewage sludge of low quality that cannot be used in farming needs detoxification and efficient recovery of the phosphorus, says Sara Stiernström, product manager at EasyMining.
EasyMining is an innovation company, part of the Ragn-Sells Group, dedicated to closing nutrient cycles. A sustainable legislation for circular economy should fulfil the following three criteria: a) real detoxification, i.e. removal and not dilution of contaminants, b) reduce the exploitation of virgin resources, and c) enable recovery and recycling of products with a quality and function suitable for their applications. Fulfilling the above criteria will assure that debts are not passed on to future generations.
– The use of new innovative processes to close nutrient cycles will play an important role to fulfil the future legislation, says Sara Stiernström.
Sludge ash cannot be used as a fertiliser
Consequently, a new circular legislation for sustainable sludge handling needs to be based on the above criteria with a special focus on the recovery of phosphorus which is classified as a critical raw material by the EU. Incineration is the leading technology for substantial detoxification of sewage sludge by destruction of organic pollutants, pathogens and plastics. Sludge ash, without further processing, cannot be used as a fertiliser due to a too high metal and heavy metal content and a too low plant availability of phosphorus. Therefore and also given its heterogeneity, sludge ash is normally landfilled today.
A market for recovered phosphorus is needed
EU is largely dependent on import of phosphorus (92%) as most phosphate mines are located outside of Europe. To decrease this dependency and to facilitate a circular economy it is crucial to establish a new legislation with high demand on recovery of phosphorus, proposing at least 80% phosphorus recovery. Recovery demands for phosphorus will not be enough to reach the goal of a new sustainable sewage sludge legislation and a toxic-free environment.
– In order for new innovative technologies to reach the market producing clean recycled phosphorus products from sewage sludge ash suitable for applications as e.g. fertilisers or feed phosphates, there is a need for clear “end of waste” criteria. Foremost, these recycled products need to be accepted on the market with no legislative hindrance if the quality demands are fulfilled, says Sara Stiernström.
Today, there is a total ban on using recovered nutrients from materials “derived from domestic and industrial waste water” and “solid urban waste” in animal feed. For the recovered phosphorus to be part of the circular economy and contribute to a sustainable sewage sludge legislation, the regulations for the downstream market, e.g. fertilisers and feed phosphates, need to be transformed from linear to circular focusing on quality and not on the origin of materials.
– It will not be enough to have a high demand on recovery of phosphorus in the new legislation. We also need to open up the market for recovered phosphorus. An quota system for blending in recycled products in fertilisers and feed phosphates would be one important step in reaching the market, Sara Stiernström says.
