Muncipal water treatment , Biology

The modern water treatment plan is often called upon to perform wonders with the water fed to it.  The clear, safe , even tasteful water that comes from a faucet may have started as a murky liquid pumped from a polluted river laden with mud and swarming  with bacteria. Or, its source may have been well water, much   too hard for domestic use and containing high levels of stain-producing dissolved iron and manganese. The water treatment plant operator's job is to make sure that the water plant product presents no hazards to the consumer.

A schematic diagram of a typical municipal water treatment plants is shown in fig. 2.1. This particular facility treats water containing excessive hardness and a high level of iron. The raw water taken from wells first goes to an aerator. Contact of water with air removes volatile solutes such as hydrogen sulfide, carbon di-oxide, methane, and volatile odorous substances such as methane thiol (CH3SH) and bacterial metabolites. Contact with oxygen also aids iron removal by oxidizing soluble iron (II) to insoluble iron (III). The addition of limes as CaO or Ca(OH)2 after aeration raises the pH and results in the formation of precipitates containing the hardness ions Ca+2 and Mg+2. These precipitates settle from the water in a primary basin. Much of the solid material remains in suspension and requires the addition of coagulants (such as iron III and aluminum sulphates) to settle the colloidal particles. The setting occurs in a secondary basin after the addition of CO2 to lower the pH. Sludge from both the primary and secondary basins is pumped to a sludge lagoon. The water is finally chlorinated, filtered and pumped to the city water mains.

 

 

Posted Date: 7/11/2012 8:30:37 AM | Location : United States







Related Discussions:- Muncipal water treatment , Assignment Help, Ask Question on Muncipal water treatment , Get Answer, Expert's Help, Muncipal water treatment Discussions

Write discussion on Muncipal water treatment
Your posts are moderated
Related Questions
what is the classification of the Gumbout Chiton?

Explain the Ebb-Phase of Stress Response? This occurs immediately following injury and lasts for approximately 24-hours. The so-called ebb phase, which is the early phase of th

What type of colour blindness is most common in men? Red-green colour blindness is the most regular form of colour blindness in men.

Compare changes in the carbon cycle to that of the nitrogen cycle on human health. Please make a conceptual graphical model for how changing the carbon cycle is likely to impact hu

Q. To increase the strength of the muscle work is the muscle contraction intensely increased? An increase in the strength of the muscle work is not achieved by increase in the

Conduits Figure: Venous Conduits Reversed saphenous vein was the first conduit used for CABG. 'It is usually harvested from the leg starting above the ankle going up

Q. What is the function of the immune system? The immune system performs specific defense against agents the antigens that are harmful to the body or foreign. Exogenous anti

BRAI N (ENCEPHELON) Shape - Oval Positio n - Situated in cranial cavity of skull. Medulla oblongeta comes out of foramen magnum in the form of spinal cord. Colou

Who was Charles Darwin? Charles Darwin was an English naturalist born in 1809 and considered the father of the theory of evolution. At the end of the year 1831, before turning 23

Define about the Listing Plane Listing proposed that only horizontal movements  of  the  eye  are performed around a vertical axis  in  the equatorial plane and vertical moveme