Kvalitetssäkring av hushållsnära avloppsfraktioner
vad kräver livsmedelsbranschen?
On-site sewage systems are common on the countryside of Sweden with approximately one million on-site systems installed. Due to insufficient function, these contribute significantly to the total discharge of phosphorus to rivers and lakes, causing eutrophication.
In order to reduce eutrophication and to fulfil one of the environmental quality objectives, the decision was taken by the Swedish Government in 2005 that 60 % of phosphorous in sewage sludge is to be recycled to arable land before 2015. To make recycling a reality, new solutions have to be found. Federation of Swedish Farmers (LRF) takes an active interest in this issue and has initiated this study.
One problem is that the food industry is sceptical towards recirculation due to the risks that products from sewage systems may contain pathogens, heavy metals and unwanted chemical compounds, e.g. medical residues or detergents. Previous studies indicate that the food industry in general agrees upon the importance of recycling plant nutrients, but for the industry to accept this recycling the products must be quality assured.
The aim of this study was to find out the requirements from the food industry for accepting recirculation of plant nutrient products from on-site systems to arable land. Focus was on three sewage products; source separated urine, source separated blackwater (urine, faeces and flush water) and precipitated sludge from septic tanks.
By making interviews with stakeholders representing the food industry and environmental organisations, different factors important for a quality assured handling were considered. A draft on a quality assurance system was produced and discussed with representatives from the food industry, an environmental agency, LRF, municipalities and environmental consultants. Their answers showed that the food industry does not require many analyses of the sewage products in order to accept recycling. They rather require the handling being checked.
However, a successful introduction of a quality assurance system implies well defined roles regarding responsibility. The municipalities and the food industry are identified as the most important stakeholders for initiation and implementation of a system for nutrient recycling.