Hamar, N

Plant capacity and performance:

• 3,600 metric tonnes DS/year	• ~65% volatile solids reduction
• 2 x 1,300 m³ digesters	• Half the original cake volume
• X kW electricity + steam	• Meets highest biosolids standards
• 2-reactor Cambi THP

The HIAS wastewater treatment plant serves the city of Hamar and several smaller towns in the 
surrounding area and treats a population equivalent of 90,000.

In 1995 Cambi built its first full-scale thermal hydrolysis installation at HIAS as part of a new sludge 
treatment process including thermal hydrolysis, digestion, dewatering and gasengine co-generation. 
It has since been in successful operation since that time 

The sludge treatment process has a capacity of 3,600 tonnes/year dry solids (DS) at 16% DS. 
The HIAS WWTP produces approx. 2,650 tonnes dry solids/year, but because of the popularity of the 
process and the end product HIAS has progressively imported more sludge from neighbouring communities. 

Thus, on 19 January 2005 Cambi AS was awarded a contract to supply an additional anaerobic digester 
in order to increase capacity. This was followed by an order in September 2006 to supply and install a 
new THP reactor and a flash tank, including associated piping and instruments, into the existing THP room.

This expansion was commissioned at the end of 2007.

The benefits of the Cambi process are: 

• 65% volatile solids reduction and maximised biogas production.
• Half the cake volume from before THP and digestion
• Integrated combined heat and power with steam production
• The biosolids product meets highest standards in Norway and can be used without any restriction
• Plant now has income from importing sludge from other plants that cannot treat sludge successfully

See Cambi's film showing some of the plants, including the plant at Hamar.

Article in the World Water Magazine "Energy price rises fuel advanced digestion"