Usage of PHOS4green Phosphate Fertilizers in Organic Farming

Organic suitability is not an utopian dream

PHOS4green consistently implements the closed-loop concept. This is also the declared goal of organic farming. However, organic farming is faced with a dilemma: because phosphorus recycling products from sewage sludge or sewage sludge ashes are currently not yet approved for use, pure rock phosphate continues to be used. However, the high energy input for mining, processing and transport from the countries of origin is anything but sustainable and basically contradicts the demands of organic farming. In addition, the quality of rock phosphate decreases and is linked to pH values below 6, while the content of toxic heavy metals such as uranium and cadmium increases – the pollutants are inevitably introduced into the soil during fertilization.

Sewage sludge and sewage sludge ashes are also contaminated with pollutants, so they must be further treated for recirculation use. PHOS4green is one of the few ash-based processes that can already be implemented on a large scale and solves both challenges: It makes the nutrient phosphorus highly available and at the same time significantly reduces the pollutant content in the end product – fertilizer-compliant, waste-free and without ash residues. Compared with rock phosphate, the clean phosphorus recycled products produced from domestic sources have equivalent phosphate content, are almost free of pollutants and, unlike rock phosphate, enable targeted fertilization effect. In addition, the bioavailability of the recyclates can be adapted to different soil conditions, and the fertilizer granules can be applied in a much more targeted and economical manner. So far, only conventional farming has benefited from the purity and process quality; organic farming must continue to hope for decisions from politicians.

We find that PHOS4green by:

  • the recovery/recycling of phosphate from a waste stream.
  • no long intercontinental transport routes – as is common in the production of conventional fertilizers – but the use of locally produced ashes
  • compliance with the limits for pollutants (see also heavy metal depletion) set out in the Fertilizer Ordinance – German Düngemittelverordnung (DüMV) and Regulation EG No. 2019/1009
  • controlled fertilization of the soil due to defined phosphate content compared to direct application of sewage sludge

is definitely a fertilizer production process suitable for organic farming and should be officially recognized as one.