Composting in sludge fields is done following:
the sludge processed in the methane tanks and the structural material – green waste and shavings, they are mixed together and put into ricks.
Composting is carried out in specially designed fields that have a cemented foundation with drainage built for this purpose. For composting are used four fields. Two fields are allocated for raw materials, one field is used as the production field, another one is used for the ready compost – here the compost is stored before selling. The ricks or the piles are formed, using the wheel loader. Once a week (or as necessary) these ricks are stirred, using a special mixer. It takes 2 to 2.5 months to prepare one batch of compost. During the composting process the raw materials are organically recycled, therefore reducing the total volume of the raw materials. Depending on the raw materials, its proportion and level of aeration, the initial amount of raw materials can be reduced almost by half during the composting.
Composting of biodegradable waste is a natural process. When composting sludge with structural materials, this process is controlled and accelerated due to aeration and the correct composting technology is observed. Aeration of the piles is ensured by stirring the materials in piles, using a special mixer.
Precipitation, as well as infiltrate from composting fields are drained to the wastewater pump station and conveyed to the wastewater treatment plants. The water is not used for production needs.