From unwanted bottles to useful bricks

When bottles arrive at Tiostone Environmental in Tuen Mun, they are crushed into glass sand which is mixed with fly ash from power plants and some other construction waste products to form bricks.

"There's no heat or fire involved in the whole process," says Dixon Chan, Tiostone's director.

Some companies, including Coca-Cola and Kowloon Dairy, reuse their glass bottles several times before sending them to Tiostone for recycling.

Tiostone, which began operating in 2005, produces between 10,000 and 15,000 square metres of bricks a year, which are mostly used for paving. At present, the company's biggest buyers are government contractors.

Tiostone ecobricks have been put to use in redeveloping Kai Tak, and are often used to pave emergency vehicle access roads.

"They can sustain the load of a fire truck," he says.