The establishment of a US$300m cement plant near Oamaru, New Zealand, was its most viable option, Holcim told an Environment Court hearing at Oamaru District Court today.
That was due to the inefficiency of Holcim’s Cape Foulwind plant, near Westport, the company said.
The Weston plant – near Oamaru – would use cleaner, dry coal burning technology which would emit less carbon dioxide, sulphur dioxide and nitrogen per tonne of cement compared with Westport, which uses wet coal burning technology, Holcim lead project engineer Stuart Ward said.
"It goes without saying you end up producing less CO2."
However, as the Weston plant would produce up about 880,000tpa of cement, he conceded the total carbon footprint of Weston would be greater than that of Westport, which produces about 500,000tpa.
Mr Ward said Holcim had considered 18 sites in New Zealand, with Weston being the most suitable option.
Building a new dry technology site in Westport would be infeasible, he said.
The Weston plant, if constructed, would be about 1km long and have an estimated stack height of 104m.
Mr Ward said the size of the plant had been chosen to supply current needs and to allow for expected market growth in New Zealand into at least the 2030s.
The significant advantages of Weston included the large deposit of high-grade easily quarried limestone near the plant site, he said.
Most of the cement would be transported to Timaru via rail and then shipped around New Zealand.
Source: Otago Daily Times Online