HKU study finds glass can replace river sand for building needs
University of Hong Kong study finds recycled materials might remove need to use river sand
Recycled glass could solve the problems of the building industry's huge demand for river sand and minimise the ecological impact on the Pearl River Delta.
The Construction Industry Council commissioned a HK$3 million study at the University of Hong Kong to seek an environmentally-friendly alternative to river sand, a key component of concrete and mortar.
It found that recycled glass crushed into fine particles could be the answer - a discovery that could mean big business for the glass recycling industry.
"The rapid developments in Hong Kong and in the region have created a huge demand for river sand," Professor Albert Kwan Kwok-hung of the university's Department of Civil Engineering said. "With a higher value, illegal dredging on upper streams has increased.
"Sometimes suppliers have quietly replaced river sand with sea sand - with its high level of salt, this could erode a building."
Following a mainland television exposé showing how sea sand was being used to make substandard building materials, 14 major building projects in Shenzhen were put on hold in March while local government officials tested concrete samples.