Nagoya City to Market Fertilizer Made from Sewage Sludge
Nagoya city officials are gearing up to market fertilizer derived from sewage sludge, recognizing its potential as a rich source of nitrogen and phosphorus for plant growth. This initiative comes at a time when nitrogen prices remain stable and phosphorus, largely imported, is experiencing a significant price surge.
The city aims to market 1,000 tons of sludge-derived fertilizer annually. This fertilizer is derived from the dead bodies of microorganisms that have decomposed human waste, a major component of sewage sludge.
Nagoya generates approximately 20,000 tons of sewage sludge daily. The city already incinerates this sludge, using the resulting ash as a raw material for cement production. Additionally, dried sludge finds application as solid fuel.
While sewage sludge has historically been recognized for its plant-promoting properties, its use as fertilizer has been limited. However, a recent policy shift by the central government, driven by rising phosphorus prices and increased global grain demand, has led to an aggressive campaign promoting its use as fertilizer.
The new policy permits the use of sewage sludge-derived fertilizer, provided its quality is consistently monitored through regular ingredient analysis.
Capitalizing on this opportunity, Nagoya city officials have decided to repurpose the solid fuel they already produce for use as fertilizer. A dedicated treatment plant in the city's Minato Ward is expected to produce around 7 tons of fertilizer daily.