In the
news release “Tuas Nexus – Singapore’s First Integrated Water and Solid Waste
Treatment Facility Begins Construction”, the National Environment Agency (NEA)
(2020) claimed that the aim of the project is to recover any drop of water
used. The used water solution system is formed by the Deep Tunnel Sewerage
System (DTSS). It further explained that Tuas Water Reclamation Plant (Tuas
WRP) can receive used water flows from two separate deep tunnels by gravity.
One tunnel is used to transport domestic water, the other to convey commercial
water of high strength. Sembcorp Architecture and Construction Pte. Ltd was
assigned in March 2020 to construct the biosolids treatment facility for the
plant. Hence, by the end of 2021, another seven-building tender valued at more
than $1 billion will be launched. Finally, phase 2 of the DTSS project is also
listed as, consisting 40 km of deep tunnels, 60 km of connection sewers, Tuas
WRP, and the NEWater integrated factory. As the consumption of water in
Singapore is expected to double in the next few decades, the Tuas WRP
incorporation is an important step to manage the growing need for the efficient
disposal of wastewater.
To begin, the consumption of water in
Singapore has always been very high. Kog (2020) stated that these innovations
will allow the future Tuas WRP to be able to be more energy-efficient and
double the energy recovery relative to traditional plants while consuming less
energy. With a net process energy utilization goal of 0.1 kWh/m3, 2.5 times
smaller than a conventional membrane bioreactor, PUB sees the upcoming Tuas WRP
as the most energy-efficient membrane bioreactor (MBR). In my opinion, the
experience gained in Singapore over the years proves that it is physically and
commercially viable to recycle and conserve water. It also explained that it
was unsuccessful at the beginning due to the high cost and unproven durability
of the technology. However, I believe as technology advances each year, the
major source of water supply in Singapore improves as well, hence moving closer
to water reclamation methods.
Next, there is a growing need for efficient
space management in Singapore because of the scarcity of land. Lay et al.
(2017) announced that the Integrated Validation Plant (IVP) and the
Demonstration Plant are part of a larger initiative to develop advanced
technologies that can be applied to the forthcoming Tuas WRP as part of Phase 2
of the DTSS project in Singapore, which is expected to be completed by 2024. I
strongly agree that the DTSS is an important part of the policy of the PUB to
address the long-term water reclamation needs of Singapore as this will
accommodate the rising need for water and cope with the effects of climate
change. Furthermore, the Tuas WRP is planned to utilize the energy-and
space-efficient MBR-RO (reverse osmosis) method for processing NEWater.
Finally, Tuas WRP is cost-efficient. Jain
(2012) revealed that DTSS is used at two large WRPs, Changi WRP at the eastern
end and Tuas WRP at the western end of Singapore, to centralize wastewater
treatment. The South Tunnel and the North Tunnel are two tunnels that will
crisscross the island and connect to these WRPs. Therefore, this centralization
leads to larger economies of scale and, reduces the cost of service in the long
run.
To sum up, there is a need to continue
improving water technology and creative reuse schemes in the future, as the
value of water reuse is gaining worldwide awareness to address the
water-food-energy nexus in the light of uncertainties and climate change. By
improving land use and enhancing energy and resource recovery, PUB is moving
towards in developing a more sustainable country.
References
Jain, P. (2012). Addressing Delhi’s water
supply problems: taking lessons from Singapore’s water management experience.
Kog,
Y. C. (2020). Water Reclamation and Reuse in Singapore. Journal of
Environmental Engineering, 146(4), 1-8. https://doi.org/10.1061/(ASCE)EE.1943-7870.0001675
Lay,
W., Lim, C., & Lee, Y. (2017). From R&D to application: Membrane
bioreactor technology for water reclamation. Water Practice &
Technology, 12(1), 12-24. https://doi.org/10.2166/wpt.2017.008
National Environmental Agency. (2020,
September 8). Tuas Nexus - Singapore’s First Integrated Water and Solid
Waste Treatment Facility Begins Construction.