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
Question 1 A patient is admitted to the hospital with suspected pneumococcal pneumonia. How would you confirm this initial diagnosis? Answer the following questions a) Which is

WHY NETWORKING IN HOSPITALS Sharing of data is essential, especially in any kind of hospital setting. For staff and doctors of a hospital, if they have details of patients rea

Q. List five advantages of DSME? Following are the advantages of DSME. It enables the patient to 1. Accept the disease. 2. Gain knowledge about disease, its prevention

Define the term- Ultrafiltration Ultrafiltration occurs when the flow of a substance across a cell membrane is increased by a hydrostatic pressure. This process was initially b

M e t h ods of curing Curing ingredients are applied in dry form or as a solution of curing ingredients in water (pickle or brine). The combination cure is applied in the i

Q. What is the pollination? What are the major forms of pollination? The procedure in which pollen grains (the male gametophytes of phanerogamic plants) reach the female gameto

figure of contractile vacuole of amoeba

For Dalmation dog, the spotted condition is dominant to non-spotted. a) Using a Punnet square, show a cross between two heterozygous parents. b) A spotted female Dalmation dog is m

Explain Pseudocoelomates in classification animal kingdom? In terms of body organization, Pseudocoelomates fall between the Acoelomates and the Coelomates. The body cavity in

Age Distribution - Population Parameters and Regulation It is obvious that individuals in a population will be of different age groups. Relative numbers of young and old indiv