- Sludge undergoing anaerobic decomposition in the digesters is not completely decomposed but is converted into a more environmentally-friendly material.
- During digestion, water is produced such that the sludge is too diluted to transport to sites for further treatment.
- In order to make the sludge more concentrated, it is dewatered with six centrifuges (see picture) that reduce sludge volume by an order of 5 to 7 times enabling the conveyance of the sludge to compost production sites outside of the plant.
* See the chart below, which describes the efficiency of the sludge dewatering process.
Sludge dewatering centrifuge
Sludge dewatering efficiency during the last five years
Output after dewatering (tons) (orange)
Input prior to dewatering (tons) (green)