reverse osmosis

Desalination

Desalination

Many times, during presentations, students ask why we cannot simply desalinate the water from the ocean. After all, whenever you look at the globe, you can see that there is a lot of blue! Why are we being asked to conserve water when water covers about 71% of the Earth’s surface? Only 3% of the Earth’s water is fresh, and the majority of that is unavailable – it is either locked up in glaciers, in polar ice caps, in the atmosphere, or in the soil, or it is highly polluted or lies too far under the Earth’s surface to be extracted at an affordable cost. 97% of the Earth’s water is found in the oceans. If we could use ocean water to drink, then we would not have a water shortage, correct? Why can we not drink ocean water? There are desalination processes, so why can we not simply desalinate the ocean water if we cannot drink it?

Ultrafiltration, Nanofiltration and Reverse Osmosis

Ultrafiltration, Nanofiltration and Reverse Osmosis

An ultrafiltration filter has a pore size around 0.01 micron. A microfiltration filter has a pore size around 0.1 micron, so when water undergoes microfiltration, many microorganisms are removed, but viruses remain in the water. Ultrafiltration would remove these larger particles, and may remove some viruses.

Water Fluoridation in Canada

Water Fluoridation in Canada

Fluoridation of water is supported by many national and international organizations. The World Health Organizations, Centers for Disease Control and Prevention, Health Canada, and multiple dental associations, including the American, Canadian and provincial associations believe water fluoridation helps with dental problems. Health Canada has even declared water fluoridation a public health issue.