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.
In the early 1900s, Onondaga Lake had a lot to offer. There was entertainment, like rowing, canoeing, strolling, swimming, fishing, and even amusement rides. Now some call it “The Most Polluted Lake in America”. Detrimental chemical dumping took place in Onondaga Lake from the 1920s to the 1990’s primarily by a company called Allied Chemical, later renamed Honeywell.
Kataka Seed. What is it? It comes from the Clearing Nut Tree and is sometimes used in India as a coagulant. What does that all mean? Coagulation can be compared to ion solvation in water. Essentially, the coagulant will bond to the suspended particles in the water that cause it to be muddy, and settle out the particles at the bottom of the water, allowing the clean water to be taken from the top. There’s a lot of existing research on this because the method of using crushed Kataka seeds to line water pots and other containers has been around since the dawn of written text. Here is a link on more reading.
While this post will have more to do with wildlife than water treatment, it is a topic relevant to Environmental Engineering and therefore is still 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. As we sailed farther from Maine and New Hampshire, the guide pointed out a stage 2 Sewage Treatment plant was built on the shore that releases water out using a schedule of high and low tides. He explained that it becomes an issue when the tides reverse, which happens every four hours. The treated sewage water then ends up where it started. He hoped and had been told that the plant is being upgraded to a stage 3 center. This simple guide explains the functions of the different stages. Continue reading “Illegal Seafoods”