Muncipal water treatment , Biology

Assignment Help:

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.

 

 


Related Discussions:- Muncipal water treatment

Birth control - permanent methods, PERMANEN T METHOD - 1. Vasectomy in...

PERMANEN T METHOD - 1. Vasectomy in male. 2. Tubectomy in female. 3. Leproscopy is used in tubal ligation , to ligate fallopian tubes.

Safety measures in the administration of drugs, SAFETY MEASURES IN THE ADMI...

SAFETY MEASURES IN THE ADMINISTRATION OF DRUGS It is essential to revise the five "Rights" before administration of medication to the paediatric group. These as you know are:

Cardiac output and its determination, The cardiac output is the volume of b...

The cardiac output is the volume of blood pumped from the heart every minute. It is obtained by the volume pumped with each beat (stroke volume) multiplied by the heart rate. The c

Is acetylcholine used in consciousness, Q. Is Acetylcholine used in conscio...

Q. Is Acetylcholine used in consciousness? Cholinergic mechanisms are important in wakefulness and cortical activation. In general, increased acetylcholine is associated with w

History of psychiatric nursing, History of Psychiatric Nursing: In 187...

History of Psychiatric Nursing: In 1873, Linda Richards, developed better nursing care in psychiatric hospitals, and organized nursing services and educational programmes  in

What is the meaning of obesity, What is the meaning of Obesity? Obesity...

What is the meaning of Obesity? Obesity is a condition resulting from accumulation of excess body fat. The fat deposition takes place because over a period of time, people cons

What are the lateral lines of fishes, What are the lateral lines of fishes?...

What are the lateral lines of fishes? The lateral lines of bony fishes are sense organs that extend along both sides of the animal body. They make contact with the environment

Fate of pyruvate, Pyruvate Pyruvate has three different  fates. Under a...

Pyruvate Pyruvate has three different  fates. Under aerobic conditions,  pyruvate enters mitochondriaand is converted to acetyl CoA. The acetyl CoA enters thecitric acid cycle.

The graph as temperature increases differ, Does the trend of the change in ...

Does the trend of the change in shape of the graph as temperature increases differ when a different gas is examined?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd