Mantova – Italy
GeoStream has produced an ammonia stripping plant from livestock waste deriving from the anaerobic digester of a biogas power plant.
The plant has a flow rate of 120m3/ dd and operates in batches.
There is a law limit for dispersible ammonia per hectare of land; the scope of this treatment is to reduce the concentration so as to allow the spreading of waste water on plots with a reduced extension.
The Geostream plant reaches an 87% abatement, allowing a 10-fold increase of the dispersible quantity per hectare.
The plant is divided into several sections:
- wastewater pre-filtration section of
- stripping section: realises a synergy with the power plant;
This is an added value both for the actual combustor and for the stripping plant that works at temperatures that favour the desired chemical reactions, guaranteeing an energy self-sufficiency. The wastewater then vaporises inside the tower, encountering the ambience air flow generated by the blowers; under controlled temperature and pH conditions, the ammonia moves from the liquid phase to the gaseous phase;
- absorption section: a vaporised acid solution reacts with the ammonia contained in the gaseous flow, forming an ammonium salt.
Out of the plant, impoverished volumes of ammonia and acidic solutions are obtained, slowly enriched with ammonium salts, significant amounts of granular fertilisers commonly used in the agricultural sector are obtained.