Italy is one of largest manufacturers of cement in Europe. With production that is in the region of 26 million tonnes per annum, it stands out from other sectors for its widespread distribution to plants over the entire nation (source: Enea operating guide).
Production of cement and its basic component, clinker, requires a high amount of energy per product unit. Specific thermal energy consumption is approximately 3700 MJ/Ton with specific consumption of fossil fuels that are mainly carbon fuels and petcoke, in the region of 3700 MJ/Ton, whereas electricity consumption in the sector has surpassed 3 TWh in 2012, which represents approximately 2.4 % of the electric consumption for the entire Italian industrial sector (sources: Operating guide for the cement production sector – January 2014 ENEA-UTEE, data from TERNA and report by AITEC 2012).
Notwithstanding significant changes in recent decades with regard to the entire production process, which led to a substantial reduction in fuel consumption and an increase in productivity, high margins of increases in energy efficiency in the industry have still been noted, which Enea estimates to be approximately 70,000 TOE of heat savings and 61,000 TOE of electricity savings, considering a percentage of completion of interventions of 50% of the possible total.
A few possible interventions:
- modification or replacement of the furnace
- installation of a multistage preheating system and pre-calcination
- use of a multi-channel burner
- thermal recovery from clinker cooling coming out from the furnace
- heat recovery from gas exhaust
- installation of mills with high-pressure grinding rollers
- fired and unbaked brick mill modifications
- use of waste fuels (CSS)
- installation of inverters on clinker cooling grid fans and on production line motors
- installation of automatic computerised control systems for various process phases
- installation of cogeneration systems