I am in a fb group called “Journey to Zero Waste”. A group of strangers who are interested in going zero-waste and we share stories and also tips on how to transit to produces lesser waste. Fabian, one of the members of the group, organised trips to Senoko Waste to Energy Plant and also, Semakau Island. In this post, I will share only on the first trip. They did not allow any photos in the plant, but I will try my best to explain with some pictures online.
To start the trip, we were shown a video and a set of slides that explains the workings of the plant and the waste management system in Singapore. Below is a summary of the information I attained from the presentation.
Waste management in Singapore
Since 1970, Lorong Halus served as a landfill where Singapore’s wastes were dumped but it was officially shut down in 1999, as landfill operations were substituted by the new offshore landfill at Semakau Landfill. There are no processing of the waste in 1970s so, the landfill or the dumping ground smelled terrible and was obviously not clean or well-managed.
There are a number of incineration plants in Singapore. Those which are operational are all Waste to Energy plants. All waste in Singapore are burned and turned to ash to reduce the volume by 90% before transported to Senoko Island for disposal.
How does waste turn to energy?
Senoko Waste to Energy Plant is an incineration plant that uses heat from burning of waste to produce electricity. When they burn the waste, the waste acts as a fuel. The heat (which is very hot – around 1200 degrees celcius), is then used to heat up water to turn into steam. The steam will then turbines that convert kinetic energy to electrical energy. The amount of energy is only 3% of the national grid.
How much do we waste in Singapore?
We waste a lot in Singapore, around 1,370 kg of waste per person. Even when our recycling rate is “high”, which is 60%, most of the recycled materials comes from the industry and not households. You can check out the statistics here.
Let’s start on the tour!
- Trash storage bunker. The bunker is a negative pressure bunker, means even when there are windows on the bunker, air only moves into the bunker. This prevents smell from the trash to escape out. We even saw birds feeding on the trash in the bunker. The claw will then scoop up the waste to be burned. The claw can carry up to 5 tons of trash in one scoop.
- Tipping Hall. We saw truck loads of trash tipping their loads into the bunker. There is a smell but it is bearable (due to the negative pressure bunker). The guide explained that sometimes they do random checking of the garbage trucks. They will ask the drivers to tip their trash on the floor, then all the recyclables will be returned back to the trucks and asked to be recycled. They also found a truck load of refrigerator before (refrigerators are not allowed to be thrown in the incinerator because it is too big to be considered general waste). The public waste collector is penalized if such accidents occur. It will reduce their chance of getting the next tender. We did ask what happened to the trash that was turned away due to the checking. The guide said usually they mixed it with the next batch of trucks that will not go through the random check.
- Central control room. The brain of the whole plant. We see workers in a room that looks like a retro control room from a ’90s movie. There are screens for the different areas in the plant including the incineration bunker. When we asked what the workers are doing, the guide explained that since the amount of waste is not constant, they have to change the variables to make sure the whole system will still be operational with more or less waste.
We end the tour with a debrief in the conference room we started in. The debrief included reminders to not throw away aerosol spray cans or full LPG tanks to the trash bins. These items can explode and harm the incineration containers in the long run. It was then followed by Q&A.
Here are some questions asked by the participants.
Q: Is there any sorting done to take out any usable recyclables?
A: No. The moment the rubbish bag is placed down the rubbish chute, the waste will be sent to incineration straight.
Q: How is the recycling system in Singapore?
A: Household recycling in Singapore needs a lot of improvement. When the recyclables are placed in the blue bins, it will collected by recycling trucks to the recycling plant. It will then be sorted by hand to the different kinds of recyclables -metal, plastic, glass and paper. If the blue bin is dirtied by food, the whole bin will be considered general waste and will be sent to be incinerated, instead of recycled.
Q: Are glass bottles recyclable if it is broken?
A: Glass bottles are only recycled as a whole. It will be washed by chemicals and then refilled and repackaged. Broken pieces of glass will not be recycled. It will be considered general waste and incinerated. This also applies to glass bottles broken due to transportation to the recycling plant.
Q: Will the plant go bankrupt if Singaporeans throw less waste?
A: No. Profit margin is smaller when there is more waste. We actually earn less now because we are processing more waste than before.
My biggest takeaway from the trip is that Singapore is very good in hiding waste from Singaporeans. Simply, our waste is out of sight, out of mind. However, our trash does not disappear when we throw it down the chute. We have to be aware and concerned that the increasing rate of waste is hurting the environment.
Another main takeaway is that our recycling system need to be improved. There is no really other way than to ensure that recycling is less expensive. To make the sorting in the recycling plant easier, Singaporeans must sort their waste before recycling or throwing them away. There must also be separate bins for different kinds of recyclables. Education must be wide spread on what can or cannot recycle so there are less pollution of the recyclables. Singaporeans who do recycle are then confident that all their effort will not go to waste. Of course, it is all easier said than done. We have a long way to go to make recycling a Singaporean culture.
Information on Lorong Halus: http://lkcnhm.nus.edu.sg/dna/places/details/19
Waste Management in SIngapore: http://www.nea.gov.sg/energy-waste/waste-management/waste-management