Sunday, February 07, 2010

North East Volunteer REAL Trail

25 January 2010

National Environment Agency (NEA) and North East Community Development Council (CDC) organised the 2nd Regional Environmental Awareness for community Leaders (REAL) Programme for Environmental Experential Learning (PEEL) land trail. The trail spanned a day, with participants meeting at the Environment Building in the morning.

The first destination was to the Biopolis building at one North. There, a representative from Envac gave us a short presentation on its Pneumatic Waste Disposal system (PWDS).

Using the concept of a vacuum cleaner, rubbish is sucked at a speed of 70 km/hr from bins to a collection point, where rubbish trucks can transport the thrash to the incinerator plant in this PWDS. This way, there is no need for cleaners to empty bins. As futuristic as the system might sound, it is already in use in several cities worldwide. According to the presenter, Biopolis as well as some condominiums are already using this system.


This is how a physical collection centre looks like:

The entire pipings and containers are all airtight. Below is a replica of the actual bin. When thrash reaches a certain level, the sensors would detect it and release the valve, for the thrash to be suctioned off.

After being collected from bin centres, rubbish lands itself at the incinerator plants. We made our way to the Tuas South Incinerator Plant where we learnt how majority of the wastes are burnt off.


Rubbish trucks are weighed before they enter the plant and after the plant, so as to determine the amount of waste disposed (and hence the costs per truck). Bulky items are not allowed to be disposed off at the incinerator plants.

The incineration plants operate 24/7.

As the rubbish truck approaches, the gate is opened for them to empty their waste.

This is where the waste will be disposed from the trucks:

The internal environment is kept at sub-atmospheric pressure so as to keep the stench inside. Operators use cranes to sieve through the rubbish to ensure there is no bulky items. Then, the cranes will feed the thrash into the furnace. Occasionally, water is sprayed on the rubbish to prevent burning outside the furnace.

We also had the chance to take a look at the control station.

And this is how the ashes look like:

We had lunch at the plant. The plates, cups and utensils were reusable, in line with NEA's cut-waste policy.

After lunch, we took a ferry to the Semakau Landfill.

The guides briefed us on the details of Semakau Landfill. I recall the guide saying that in the old days, there used to be the uncles selling wanton noodles along the street. After taking away back home and finishing the food, people would return the carrier to the vendor. This is unlike the current culture of "use and throw".

Incinerated ashes are shipped to the island via a barge. When the ashes arrive, special cranes grab the ashes and transport them to the dump trucks, which will empty them in one of the cells to be buried.

The cells are coated with special geographic membranes that prevent toxic waste from contaminating seawater. Mangrove swamps which line part of the coastal areas of the island also act as sensors for contamination.

Inspection wells enable NEA officers to check the quality of water.

The scenic view from the island is astonishing. I remember coming to this very island a year ago with the YEC for retreat. Sleeping out in the open for a night is a wonderful and memorable experience.




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