Less odour with Yuhua's automated waste collection system

Residents will be able to drop recyclable waste into outdoor inlets such as this, which will carry the rubbish to the centralised bin centre. -- -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES 
Residents will be able to drop recyclable waste into outdoor inlets such as this, which will carry the rubbish to the centralised bin centre. -- -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES 
The Exhaustor, part of the new pneumatic waste collection system being tested on several HDB block in Yuhua, is a centrifugal pump that creates suction, in the centralised bin centre on May 28, 2015. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
The Exhaustor, part of the new pneumatic waste collection system being tested on several HDB block in Yuhua, is a centrifugal pump that creates suction, in the centralised bin centre on May 28, 2015. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
Rubbish thrown into household chutes will be gathered at centralised precinct bin centres, which will make it easier for waste collecters to retrieve the garbage. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
Rubbish thrown into household chutes will be gathered at centralised precinct bin centres, which will make it easier for waste collecters to retrieve the garbage. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
A staff member monitoring the pneumatic waste conveyance system in the control room of the centralised bin centre on May 28, 2015. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
A staff member monitoring the pneumatic waste conveyance system in the control room of the centralised bin centre on May 28, 2015. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
The Cyclone, part of the new pneumatic waste collection system being tested on several HDB block in Yuhua, creates a spinning effect so that waste can go down and air goes up in the network of pipes. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES
The Cyclone, part of the new pneumatic waste collection system being tested on several HDB block in Yuhua, creates a spinning effect so that waste can go down and air goes up in the network of pipes. -- ST PHOTO: LIM YAOHUI FOR THE STRAITS TIMES

SINGAPORE - Foul-smelling rubbish chutes will soon be a whiff of the past at Jurong's Yuhua estate, as blocks there get retrofitted with high-tech waste collection infrastructure.

Since early May, six blocks in Yuhua have been using the pneumatic waste conveyance system, which uses vacuum-type underground pipes to automatically gather household garbage, doing away with the usual manual method of collection.

A total of 38 blocks in the estate, or about 3,200 households, will have it by the third quarter of this year, as part of the Housing Board's Greenprint programme.

If deemed feasible, the same system will be rolled out to other housing estates.

Under this automated method, rubbish thrown into household chutes will end up in bins at the bottom of blocks. When the bins are full, sensors will instruct valves to open and drop trash into underground pipes.

Garbage is then transported by air suction to a centralised bin centre in the precinct under a minute, at a speed of 50 to 80 kmh.

Outdoor disposal inlets where the public can throw recyclable waste will also be linked to the system.

As waste collectors only need to retrieve garbage from one point and less frequently, this system is estimated to reduce manpower needs by about 70 per cent, said HDB's deputy director of technology research Tan Chek Sim.

He added that this method gives residents a cleaner and greener environment. Said Mr Tan: "The entire time, rubbish is not exposed. There is no spillage so there is less smell."

Residents in blocks which have piloted the system agreed.

"We also don't have to worry so much about pests like cockroaches now," said housewife Helen Leong, 45.

Retiree Kwek Han Tiang, 67, said: "It's great that we have new technology like this. Singapore is a first world country after all."

HDB cautioned that bulky items such as bamboo poles and pillows might choke the pipes, which are 50cm in diameter and run about 4.6km.

But if this happens, the suction power will be automatically increased to unclog the blockage, said Mr Tan. There are also manholes which allow for manual access to the pipes if needed.

While this system has been test-bedded at some HDB blocks in Kim Keat, Choa Chu Kang and Clementi, Yuhua is its largest implementation in Singapore. Upcoming housing projects at Tampines North, Bidadari and Punggol Northshore will also come with it.

The Greenprint scheme for Yuhua, which started in 2012 and will end this year, aims to transform the estate into Singapore's first green neighbourhood. It is estimated to cost about $23 million.

Other green initiatives include rooftop solar panels and double-tiered bicycle racks.

The pneumatic waste collection system is expected to take up more than half the cost, given its large scale and extensive network of underground pipes, said HDB.

yeosamjo@sph.com.sg