Imagine you are on a conveyor belt. The conveyor belt is circling around a box of pizza. Every time you get close enough, you take a slice of pizza. If the conveyor belt moves too fast, you can’t grab the pizza. But if it’s too slow, you’ll starve and the pizza won’t be nice and hot anymore and it might even start to grow mold. This is how the activated sludge process was explained to me in my first Environmental Engineering lecture many moons ago.
Did you know that bubbles can clean water? Specifically, dissolved air flotation (DAF) and ultrasound are two methods of making water safer with bubbles. DAF can be used to replace sedimentation in municipal drinking water treatment. Large particles are typically settled out using gravity, but with DAF, bubbles are produced by an oxygen tank pumping air into the bottom of a basin and small particles attach to the sides of the bubbles. The bubbles rise to the top of the basin and the particles are swept off the surface of the water by a skimmer.
For my friend James, running water is a soothing noise. For me, gushing water is the definition of aggravation. I can’t help but think of all the other uses for clean water besides going down the drain, while someone brushes their teeth in the mirror. But all this talk about water brings back a memory.
While this post will have more to do with wildlife than water treatment, it is a topic relevant to the environment and therefore is significant in environmental consciousness. Recently, while traveling to Maine I learned about the history of the waterfront. Native Americans and settlers lived along the Piscataqua river waterfront that serves as a harbor to the Atlantic Ocean. It later became an important location in defending the US from submarine attacks.