A founding principle of rendering is that there is no such thing as waste, only useful by-products. This principle means that the rendering industry is full of examples of sustainability and the circular economy in action.
Two new case studies highlight how ETSA in Portugal and Honkajoki in Finland improving food security through sustainable use of by-products.
It is estimated that in the EU 173kg of food per person per year is lost or wasted at some point on the supply chain from farm to fork. This represents a huge overall loss as the time, energy and resources used to produce the food are lost as well. Prevention is the most important step to improve sustainability, but some losses are unavoidable, this is where ETSA come in.
ETSA collect former foodstuffs from retailers and processors. Material is segregated so meat can be processed with Category 3 by-products (fit for human consumption at the point of slaughter), fish is processed into fish feed, and dairy and bakery products are used in pig feed. Any material that is too deteriorated and is a potential hazard is processed on a Category 1 ABP line.
ETSA ensure maximum value is taken from these materials which would otherwise go to waste. It also contributes to animal feed and protein production which benefits the local livestock industry.
The rendering facility of Honkajoki in Finland has developed a way to convert ammonia rich condensate from the rendering process into nitrogen fertiliser. In the standard rendering process condensate is typically combined with wastewater from the site and sent for treatment in a wastewater treatment plant.
Honkajoki processes this ammonia-rich condensate separately to produce a renewable nitrogen fertiliser and clean water, available for reuse on site or in other applications. This reduces the volume of wastewater to be treated dramatically. Unlike most renewable fertilisers which are ammonium-based and require a nitrification step in the soil, this product contains nitrogen as nitrate which is immediately available for the crop to use.
The technology pioneered by Honkajoki could be applied to other sites and offers a useful source of nitrogen fertiliser which is typically energy intensive to produce.