Biosolids

Nutrient content

This provides long-term cultivation security for you.

Phosphorus	>6–10 kg/t
Nitrogen	7–13 kg/t – utilization requirement for N is 50%
Potassium	approx. 1 kg/t
Mg & S	Contains smaller amounts

Information

Application

Biosolids are particularly well-suited for grain crops grown to maturity and as a pre-treatment before rapeseed. They are applied using a sludge spreader or manure spreader. The material has a scoopable consistency, with a typical dry matter content of 18–30%.

The latest figures show that as much as 77% of the biosolids produced at Danish municipal wastewater treatment plants are applied to agricultural land. This is the highest proportion ever recorded and demonstrates both that a large share of the biosolids meet Denmark’s strict limits for unwanted substances—which, incidentally, are among the toughest in Europe—and that Danish farmers trust the product, recognizing its economic value and positive effects in the field.

There are certain hygiene requirements and other regulations associated with the use of biosolids, and Miljøservice maintains full compliance with these, ensuring that the biosolids used on your farm are handled correctly and in accordance with the “Waste to Soil” regulation.

Delivery

Biosolids may be used on all conventionally managed fields that receive less livestock manure than the equivalent of 30 kg of phosphorus (P) per hectare per year, and where the crop, according to the “Waste to Soil” regulation (DK: Affald til jord bekendtgørelsen), is permitted to be fertilized with biosolids. Organic farmers have shown interest in using biosolids, but a regulatory framework is not yet in place

We deliver—by agreement with you—often to a transfer depot in the field, after which we ensure spreading via a local agricultural contractor.

Origin

Biosolids originates from processes at wastewater treatment plants, where microorganisms feed on the organic material in the wastewater, and the nutrients multiply rapidly before the organisms die. This results in a sludge residue with high fertilizer value

Well-Documented Fertilizer

Biosolids is likely the most studied and well-documented type of organic fertilizer on the market. At the same time, its application is highly regulated. Only sewage sludge that meets strict limit values is used as fertilizer.

Consistency

Biosolids has a scoopable and spreadable consistency. The dry matter content is between 20–30%.

Residual Products Can Be Combined

Residual products can be combined in accordance with the “Waste to Soil” regulation, which sets a maximum of 170 kg total nitrogen (N) per year. If you only supplement biosolids with commercial fertilizer, there are no issues. However, combining it with livestock manure is also possible.

We deliver nationwide

Miljøservice supplies biosolids to farmers across Denmark—either directly from wastewater treatment plants or from storage facilities strategically located near both treatment plants and spreading areas. We always strive to match locally produced biosolids with local farmers whenever possible, to minimize transport and thereby reduce CO₂ emissions.
Biosolids primarily replaces phosphorus, which is a limited resource. Approximately 25% of the phosphorus used in Danish agriculture (excluding livestock manure) now comes from biofertilizer!

How to Proceed

You contact one of our project managers.

Based on the information you provide, Miljøservice prepares a delivery agreement and delivery notice, specifying the field number, field size, expected delivery time, and a field map. We also provide details on the content of nitrogen (N), phosphorus (P), and potassium (K), along with suggestions for supplementary commercial fertilizer. You contact us—or we contact you—when the spreading time approaches.

Watch the spreading of Biosolids in action

Good Reasons to Use Biosolids

Fertilizer delivered and spread free of charge.
Kontant Direct area compensation included – with a 3-year application, biosolids replaces commercial fertilizer worth over DKK 1,000/ha.
Maintains the soil’s nutrient pool throughout the growing season, with residual effects in both the 2nd and 3rd year.
Increases the soil’s humus and carbon content, enhancing biological activity and improving soil structure.
Environmentally friendly and sustainable fertilizer that recirculates valuable, scarce resources.
Locally produced product, ensuring a minimal climate footprint.
Digested (de-gassed) biofertilizer causes minimal odor nuisance.
Strict regulations and limit values ensure high quality.