The Australian Greenhouse Office (AGO), the world’s first government agency dedicated to cutting greenhouse gas emissions, has benefited from design, documentation and on-going advice from GHD during the construction phase for the mechanical and fire services in the 3,500 square metres of the agency’s refurbished office space.

Design implementations to systems such as the offices air conditioning include applications such as delivering the air at floor level because the resultant air flow patterns, from floor to ceiling, more efficiently remove heat and contaminants. This system alone, using just one air handling plant, will reduce energy consumption by up to 25% compared with conventional systems.

Additionally in Victoria’s Latrobe Valley Hazelwood power station, a GHD system of thickened ash pumping and disposal has been used to dispose of the large amounts of ash produced by the coal-fired power stations, the bulk of which is collected in hoppers at the bottom of precipitators, sluiced into a pit and then pumped as a mixture of 95% water into an ash dam.

GHD is using technology from the mining industry to convert this low-concentration solution into thickened ash slurry. Benefits of which include less impact on the environment by reducing the risk of groundwater contamination, greater disposal efficiencies and improved safety through the elimination of multiple handling, and a reduction in fuel consumption and water pumping costs.

“Recent developments in thickener technology mean that we can transform the 95 to 5% ratio of water to ash in the ash sluice water down to a 50/50 ratio, and the thickened material is virtually solid once it is deposited in the ash containment area. This allows it to be deposited into areas such as overburden dumps within the mine, that was not feasible with the previous slurry,” said project manager Ken Keam.

The Hazelwood project is due to be commissioned in 2005, and the team is now assessing the system’s direct application for other mines in the Latrobe Valley.