Much scope for waste reduction

I WAS interested to read the letter from Dr Mike Chiu, of the Environmental Protection Department (EPD), which appeared in these columns on October 5.

There is no doubt in my mind that every society requires an integrated approach to waste reduction/recovery/disposal and that the ultimate solutions may be quite different for different societies. In my view the most important point is to reduce the amount of waste generated and I note that the Government is now actively involved in a Waste Reduction Study.

My experience as a member of the Environment Committee of the Hong Kong General Chamber of Commerce, indicates there is much scope for waste reduction in Hong Kong.

As an example the dumping of construction waste to landfills has been a serious problem and at times in excess of 10,000 tonnes per day have been disposed in this manner.

Our studies indicated that over 70 per cent of this material was re-usable in the sense that after segregation it could be used as fill in one of Hong Kong's many reclamations.

Other options include the recycling of waste concrete and rubble into construction aggregates - a system in use in the US.

As regards incineration, Dr Chiu may not be aware that Hong Kong already has a most efficient incinerator - the cement kiln at China Cement's integrated cement plant at Tap Shek Kok in the New Territories.

This kiln, with internal temperatures exceeding 1,400 degrees centigrade, is a very useful tool for the disposal of certain organic wastes and this practice is now widespread in the cement industries of Europe and the US. China Cement is working closely with the EPD to implement an environmentally friendly disposal programme and if successful, we will then be able to reduce our coal imports - a non-renewable resource.

At the same time China Cement is using very large quantities of coal ash from the two power utilities in its cement manufacturing process.

This material was previously dumped but is now being efficiently recycled.

These are examples of the integrated approach to waste management.

I hope the forthcoming Waste Reduction Study will suggest similar options.

Barrie Cook, Managing Director China Cement Company (Hong Kong) Limited