The Italian company
Multiservizi will install a sludge belt dryer from Siemens Automation at its
plant in the city of Jesi, Ancona. Once the dryer becomes operational in 2012,
it will allow the plant to reduce the amount of biosolids produced annually by
roughly 75 percent. The belt dryer evaporation capacity is 2000 kg/hr.
Multiservizi is a publicly
owned Italian company that operates water and wastewater treatment plants for
45 communities in Italy. The plant in Jesi serves 60,000 residents. Siemens is
the world’s largest automation vendor.
The dryer will reduce
sludge production from 16,500 to 4,125 tons per year. The plant, which also has
a natural gas boiler, recovers thermal energy from the cogeneration plant, thus
reducing CO2 emissions.
With the sludge belt
driver, evaporation takes place when biosolids come in contact with the heated
air. Biosolids are evenly distributed on the entire belt width to cause uniform
evaporation across the two-belt system configuration. Belt speed and process
air temperature are adjusted for different residence times based on required product
moisture to meet final use or disposal requirements.
Siemens says its
technology was selected because of its high reliability and safety, low
maintenance, and high automation level. Other advantages include high energy
efficiency, minimal environmental impact, and agriculture-grade pathogen
approximately 4 million tons of biosolids annually – almost half of which is
currently sent to landfill with another quarter used for agricultural purposes.
Limited landfill space and rising transportation costs are heightening the need to
use technologies that reduce sludge volume.