With a designed capacity of 200 cubic meters per hour, the factory on Vietnam’s biggest island began operations on Wednesday, becoming the first of its kind in Vietnam.

The factory uses a sand cleaning and sifting technique developed by engineer Vo Tan Dung, now owned by Phan Thanh Construction Trading and Transportation Joint Stock Company in the southern city of Can Tho.

The technique uses water pressure to cut the structure of sea sand, removes salt and organic impurities, and then filters it again to get sand that could be used for building projects.

Before this commercial operation began, this technique had won Dung the World Intellectual Property Organization award in 2011.

It was tested by experts from the Vietnam Institute for Building Science and Technology under the Ministry of Construction in March last year in Ba Ria-Vung Tau, a coastal province next to Ho Chi Minh City.

Then earlier this year, it was tested again using the sand collected in Phu Quoc.

The results from both tests showed that in the treated sea sand, the amount of acid-soluble chloride content, dust, clay, organic impurities and mud dropped significantly, making it suitable for construction projects.

Dung said he hopes the sand cleaning technique will contribute to cooling down the construction sand fever that has been raging across Vietnam, leading to illegal sand mining in rivers and coastal areas.

Illegal sand mining has caused severe land erosion, collapsed and washed houses, and continues to threaten the livelihoods of people who depend on the water bodies.

Global demand for sand and gravel, used extensively in construction, is about 50 billion tons or an average of 18 kg (40 lb) per person per day, according to a report published by the U.N. Environment Program (UNEP) in May this year.

Extraction in rivers and beaches has increased pollution and flooding, lowered groundwater levels, hurt marine life, and exacerbated the occurrence and severity of landslides and drought, it said.

"We are spending our sand 'budget' faster than we can produce it responsibly," Joyce Msuya, UNEP's acting executive director, was quoted as saying in the report.

Current legal frameworks are not sufficient, and "sand mafias" comprising builders, businessmen and dealers in countries such as Cambodia, Vietnam, India, Kenya and Sierra Leone regularly flout existing laws, the UNEP report said.