In its latest sustainability report, Italy-based cement maker Italcementi reported advances in energy efficiency in the countries where revamped plants were commissioned. Energy efficiency at its Martinsburg, USA, works benefitted from a new kiln system that replaced the former wet kilns, reducing its specific thermal consumption by 40 per cent and resulting in the reduction of its North American plants by 11 per cent. Further gains were made in Matera (Italy) and Yerraguntla (India). Group-wise, more modest advances were made with thermal energy consumption falling from 3970MJ/t of clinker to 3915MJ/t of clinker.
The fuel mix showed significant changes in Egypt where gas was favoured over oil, and in Bulgaria, which saw its use of coal increase to 34 per cent at the expense of petcoke. Overall, around five per cent of energy came from alternative fuels with advances particularly noted in Spain and the US. The use of liquid AF increased significantly as did tyres, rubber and solid waste. In contrast, Italcement reduced its relative use of animal meal, agricultural and plastics to fire its kilns.
Both gross and net CO2 emissions crept up during the year to 723kg/t cement and 714kg/t cement, respectively – somewhat off the 2012 target of 690kg/t, which represents a five per cent reduction when compared with 1990 levels. For 2014, a more stringent target of 640kg/t is set. “The Group supports the supports the reduction plan by improving thermal process efficiency, using optimised fuel mix and alternative sources of energy, with high content of carbon-neutral biomass, and increasing the percentage of alternative raw materials with reduced carbon footprint and cement blending,” it said. Planned investment in Egypt, Bulgaria and India are expected to build on investments already made in India and Morocco to reduce the group’s CO2 emissions.
Power consumption rose slightly from 121.5kWh/t of cement to 121.6kWh/t.
The use of raw materials saw no great changes overall at 5.7 per cent but relatively more iron and calcium substitutes were used. The company’s clinker factor remained stable at 81.6 per cent.
In terms of air emissions, Italcementi made limited progress towards its dust emission target of 130g/t of clinker, falling from 199g/t clinker to 193g/t although dust levels in emerging countries remain relatively high. Nevertheless, the group reported action in that area as it completed an ESP-to-bag filter conversion in Fuping, China and a further such project planned for Marrakech, Morocco. A more significant advance was made in the area of SO2 abatement, where emission levels fell from 440g/t of clinker to 360g/t, greatly surpassing the 570g target further, following the turndown of the Agadir kilns. Gains in NOx reduction made in recent years went into reverse as NOx output increased from 1459g/t of clinker to 1672g/t, but remained below the 1760g/t target.