He said the Hammarby model - where waste is regarded as a resource - was being adopted by some cities on the mainland.

Every week the 1.7 sq km eco-city hosted guests from the mainland, who toured the town to see how the green initiatives worked and how they might translate at home, said Freudenthal, who works at the environmental information centre.

'They started to come to us in 2003, 2004, and now we have one or two every week,' he said, adding that cities planning to incorporate Swedish green technologies included Wuxi, Danyang and Gongqing.

In Hammarby, the eco-city of 20,000 features comprehensive built-in systems to manage solid waste. A series of underground chutes for every apartment block divides waste into three categories.

Food waste is composted and turned into soil with plans to convert it into biogas; combustible waste is incinerated and produces energy for district heating and electricity; and paper, metal, glass and plastic packaging are recycled into new goods.

The project has been so successful that Stockholm is creating a second similar development in another harbour area, which will have 10,000 apartments and accommodate 30,000 workers.

'If you look at all the waste produced in Sweden, from households, building sites and industry, about 8 per cent goes to landfill. The rest is reused or used to produce energy,' Freudenthal said.

He also highlighted the benefits of a 'producer pays' programme to manage waste, something the Hong Kong government has introduced to a limited extent.

'When you buy a plastic or paper bottle of detergent, or food in a tin, a small portion goes back to the producer and that money is used for collection costs,' he said.

'It is the producers' responsibility to collect the packaging.'

But this move would work only if there were legislation to enforce the initiatives, something that existed in Sweden, he said.

'This model can work in Hong Kong, but you have to introduce it gradually because it requires education at the same time. You also have to tell people why you are doing it.'

In 2009, Hong Kong produced 6.45 million tonnes of rubbish, more than double the amount two decades ago. Translated into a per capita figure, this meant each of its seven million people produced 921kg of municipal solid waste.

The recycling rate in Hong Kong is currently 49 per cent, and the Environment Bureau is aiming to increase this to 55 per cent by 2015.

The government has proposed a controversial plan to build a large incinerator, with a capacity of 3,000 tonnes a day, on a reclaimed site at Shek Kwu Chau, south of Lantau Island.

Environment officials have not ruled out the need to build an extra incinerator to cope with mounting waste.

751

The amount, in tonnes, of paper, metal and plastic Hong Kong recycled last year

- 686 tonnes were recycled in 2009