Recycled copper slag plant prompted by last year's sand supply crisis
Jessica Cheam, Straits Times 30 Oct 08;
THE building industry is taking steps to make itself more green with the opening yesterday of a new plant which will recycle used copper slag to make concrete.
The $6million facility in Sungei Kadut can process up to 360,000 tonnes of copper slag - an industrial waste material collected from local shipyards - a year.
This material can act as a substitute for sand in the making of ready-mixed concrete, which is heavily used here for building construction.
The 10,000sq m plant was developed by Geocycle Singapore, a joint venture of cement maker Holcim Singapore and mainboard-listed recycler ecoWise Holdings, and marks a milestone for the local construction industry.
Holcim Singapore chief executive Sujit Ghosh said the plant and its technology came about as a result of a 'sand crisis' that hit the building industry early last year. It was triggered when Indonesia abruptly banned exports of land sand, a move that caused prices to triple at one point.
'This led to a sudden and serious shortage of supplies of sand...the search for an urgent replacement was on in earnest,' said Dr Ghosh.
An early partnership with ecoWise, a leading copper slag collector, led to a series of tests - with the Building and Construction Authority- on the viability of using copper slag as sand in concrete.
'Despite stringent standards of safety...it came out with flying colours,' said Dr Ghosh.
Demand for green construction products has also been growing in tandem with environmental awareness, he said.
This led to the formation of Geocycle to meet this rising demand for recycled building materials.
EcoWise chief executive Lee Thiam Seng said about 15per cent of the processed slag would be sold back to shipyards, while concrete suppliers will buy the rest.
Mr Lee declined to reveal the price, but said that the cost of processing used copper slag was cheaper than the $40 a tonne price of sand.
This means developers who want to use green concrete, which uses this recycled material, will not have to pay a high premium for it, he added.
Geocycle is also carrying out research on other materials which may help promote sustainable construction. One avenue of investigation is how to recycle bottom ash from incinerators, which is toxic, into a material with sand-like properties.
Parliamentary Secretary (National Development) Mohamad Maliki Osman, who was at yesterday's launch ceremony, commended the industry's move towards greener construction practices.
'With increasing pressure on resources and the environment...Singapore will stand to benefit even more from alternative resources and resource efficiency,' he said.
What is sustainable construction?
Straits Times 30 Oct 08;
SUSTAINABLE construction involves building and designing eco-friendly buildings that reduce adverse impact not only on the environment but also on the health of their occupants.
The Building and Construction Authority (BCA) encourages green buildings here with its Green Mark Scheme.
It rates buildings for their environmental performance and provides financial incentives to go green.
The scheme aims to promote sustainability and raise environmental awareness among developers, designers and builders when they begin designing a building as well as during construction.
One example of sustainable construction is the use of products that are made from recycled materials.
Holcim Singapore and the BCA have developed a product called 'Holcim Green' that promotes greener building practices.
This is a form of concrete which uses recycled material such as granite from demolition debris and used copper slag as sand.
Developers who use this form of green concrete, for example, can score extra points in the assessment of their buildings under the Green Mark scheme, said Holcim Singapore chief executive Sujit Ghosh.
The BCA Green Mark is awarded based on five key criteria:
# Energy efficiency
# Water efficiency
# Site/project development and management (building management and operation for existing buildings)
# Good indoor environmental quality and environmental protection
# Innovation
