what is the importance of total suspended solid removal from drinking water?

Question

i wonder how suspended solid could be so much important to be removed from our drinking water and if possible could someone describe these process of removing suspended solid treatment in a simple step by step

Answer 1

One of the main reasons total suspended solids are an important factor in treating drinking water is that Giardia cysts (among other pathogens) can not be inactivated with conventional disinfection (chlorine). They need to be settled and filtered out. Every water treatment plant is run a bit differently, but I can explain the process at my plant:

Raw water is pumped from the river to our reservoir. As the water starts its journey through the plant, we add aluminum sulfate as a coagulation aid. It makes the suspended solids stick together to make larger particles that will settle easier. After passing through several mixers (each at a slower rpm), the water is sent to a settling basin. As the water moves across the basin, the particles (called floc) settle to the bottom, while the water continues across and out of the basin through troughs. At this point, our plant adds a first dose of chlorine to disinfect the water. The water then heads to our filters (ours are 5 feet of anthracite coal above 1 foot of gravel). After the water is filtered, we add another dose of chlorine to get the residual to the proper level so there is still a residual when the water is sent to the distribution system. We also add fluoride, sodium hydroxide (for pH control) and zinc orthophosphate (for corrossion control). The water is then sent to the clearwell to await its journey into the distirbution system.

The EPA has a website with the federal regulations regarding drinking water. http://www.epa.gov/ebtpages/water.html

Check with your state's environmental department for regulations they have as well.

If you have any questions, feel free to email me.

Answer 2

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