Location:

• Town/village: Nacław
• District: Polanów
• County: Koszalin
• Province: Zachodniopomorskie

Project description:
The agricultural biogas plant in Nacław produces biogas and generates electricity and heat through its combustion. The input material is composed of liquid pig manure mixed with supplementary components: corn silage, glycerine and waste from crop production. The type and quantity of substrates used are monitored daily, so as to obtain the highest efficiency of the system and equal distribution during fermentation. The biogas is produced in a process of mesophilic digestion (fermentation) at a temperature of 37˚C, in anaerobic conditions. The biogas produced in the fermentation process is combusted in a cogeneration unit generating electricity and heat. The resultant electric power is partly consumed by the plant (5–10%) and the adjoining pig farm (10–15%), and the remainder (75–85 %) is sold to a power company. The heat recovered from engine cooling is used for technological processes of the plant and will be supplied to external customers.

The Nacław biogas plant is composed of the following facilities:

• component storage area with a feeder, with total area 288 m2
• component storage tank no. 1 with capacity 32 m3
• component storage tank no. 2 with capacity 32 m3
• pre-storage tank with capacity 1,000 m3
• fermenter with capacity 1,250 m3
• post-fermentation tank with capacity 2,000 m3
• service building
• service shed with mixing tank
• cogeneration unit with a power of 625 kWe and 680 kWt
• heat furnace with a power of 690 kW
• emergency cooler
• two-chamber tank for pre-fermented liquid manure – 2 x 10,000 m3

Annual input material to the Nacław plant:

• liquid manure feedstock – 20,000 tonnes per year
• corn silage feedstock – 13,800 tonnes per year
• glycerine feedstock – 4,700 tonnes per year (optional)

Annual output of the Nacław plant:

• biogas – approx. 2,300,000 m3
• electricity – approx. 5,300,000 kWh
• heat – approx. 5,900,000 kWh