Composting plant Novara
Agriter SrlS. Nazzaro Sesia | Novara - Italy
- System description: Composting
- Waste processed: Organic waste, garden waste and sludge
- Plant capacity: 50,000 t/year
The facility includes composting of organic waste and sludge. The waste-hygienization process is based on a spontaneous rise in temperature caused by bacteria and molds which develop in the biologically-treated mass. The plant is designed for composting a waste mixture consisting of the following components:
• Organic waste from source separation, such as kitchen waste or market waste;
• De-watered sludge from the biological treatment of waste water;
• Shredded structural material, e.g. wood waste from gardens.
The waste hygienization process is based on the spontaneous increase in temperature induced by bacteria and molds developing in the organic mass undergoing forced aeration. The floor of the composting building has built-in air ducts with nozzles for the distribution of air through the piles of material. The aeration system is modular. Therefore, the air flow can be varied according to the stage of the process in each area of the composting building. The material which first starts the process is the first to leave the composting building to be further processed. Centrifugal ventilators, made of stainless steel and set up outside the building, are used to keep the longitudinal air duct under positive pressure so as to distribute air to the ducts integrated in the floor. The building is equipped with a pre-existing odour control system supplied by third parties. The composting process is monitored by a computerized system that keeps the material temperature under control, as well as the pressure and airflow rate in each unit. The system includes a sensor for measuring the oxygen content in the air being blown in. Its purpose is to adjust the ratio between the air drawn inside the building and the fresh air coming from outdoors. Air flow is adjusted automatically by means of the electric drives of the air dampers. To limit power consumption, every ventilator has a motor with a variable frequency drive that adjusts the speed of the ventilator according to the requirements of the process.