Wednesday, April 27, 2011
Different ways Singapore had dealt with water constraints.
Singapore dealt with their water constraints by importing water from their neighbouring country, Malaysia, collecting rainwater and used water, further purifying water and also desalinating water.
The water imported from Malaysia supply half of Singapore’s water consumption. They signed a treaty in 1961 and 1962 respectively and it will soon expire in 2011 and 2061.
Singapore collects their rainwater through drains, canals, rivers, storm-water collection ponds, and it will then lead to the various reservoirs for storage before being treated and further purified.
NEWater acts as a pillar of Singapore’s water sustainability by further purifying the water that are collected and stored in the reservoirs. By coming up with this system, it meets 30% of Singapore’s water requirements.
Singapore desalinates sea water and it meets 30% of Singapore water requirements. Observers suggested that Singapore could become the world’s water hub in recycling water and can even export desalinating technology to other parts of the world.
Description of the process of desalinating water.
(Above is the picture of how water is being purified through Reverse Osmosis.)
All suspended solids are removed, and the water pre-treated so that salt microbial growth does not occur on the membranes. Coagulation chemicals are used to attract particles together that will not readily settle or filter out of the water. Flocculation is a gentle mixing of coagulated raw water that allows particles to now gather to form larger, heavier particles. The sedimentation process settles out larger suspended particles and the particles created through the coagulation process and the heavy particles fall to the floor.
High pressure pumps supply the pressure needed to enable the water to pass through the membrane and have the salt rejected. The pressures range from about 150 pound-force per square inch (psi) for slightly brackish water to 800 - 1,000 psi for seawater.
Description of how water in collected in the Water Catchment Areas.
Rainwater is collected through a comprehensive network of drains, canals, rivers, storm-weather collection ponds and reservoirs.
Description of the process of purifying water in NEWater.
(Above is the picture that shows how water is being purified at NEWater.)
NEWater purifies water through a three-stage process. Going through micro-filtration, the unwanted substances such as suspended solids, minute particles, disease-causing bacteria and viruses are filtered out by membranes, leaving only dissolved salts and organic molecules.
At the reverse osmosis stage, the water passes through tiny pores in a semi-permeable membrane which only allows very small molecules like water molecules to go through. This ensures that undesirable contaminants such as bacteria, viruses, heavy metals, disinfection by-products, etc, are eradicated. The end result is high-grade water that is free from viruses and bacteria and contains very low levels of salts and organic matters.
As an added safety measure, the high-grade water next undergoes ultraviolet disinfection, guaranteeing the purity of the product water. Some alkaline chemicals are then added to restore the pH balance of the water. The end product water is ultra-clean and safe for drinking.
Description of imported water from Malaysia.
The above picture shows the water pipeline of Malaysia that runs through the Johor-Woodlands causeway to Singapore.
The best method we chosen and the reasons.
We think that the best method would be the process of desalinating water. Close to 97% of water on earth is salt water, 3% are fresh water, and less than 1% of the water is readily available as majority of it are ice. Since we are able to desalinate sea water through the process of Reverse Osmosis, and Singapore had been doing so for the pass few years, we think that it would be the best method readily available for us to use. Although the cost of the machine and mechanical parts are expensive, we are sure that it would benefit us in the long-run.
As compared to the other possible methods, we strongly object to the idea of buying water from our neighbouring country even if they are willing to sell at a low price. This is because small amount of money adds up to a large sum, and we would rather invest it on something more beneficial. We considered using the way of purifying water at NEWater, but what if we face crisis such as drought, and a large amount of used water isn't available for us to purify, or the machines isn't fast enough to purify the used water, we would not be able to get that extra amount of water that our citizens need.
|