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

Explain the limiting factors for the growth of a population, What are the m...

What are the main limiting factors for the growth of a population? The factors that limit the growth of a population can be divided into biotic factors and abiotic factors. The

What is energy, What is Energy ? Energy Energy is defined as the cap...

What is Energy ? Energy Energy is defined as the capacity to do work. Work is defined as the movement of a mass, or the product of the force and the distance through which t

Health hazards with poor management of bio-medical waste, Health Hazards wi...

Health Hazards with poor management of Bio-medical waste Health hazards associated with poor management of Bio-medical waste are: - Injury from sharps to staff and waste han

What are allosteric enzymes, What are allosteric enzymes? Allosteric re...

What are allosteric enzymes? Allosteric regulators can be allosteric inhibitors or allosteric activators. The interaction among an allosteric enzyme and the allosteric inhibito

What do you mean by lofenalac, Q. What do you mean by Lofenalac? Lofena...

Q. What do you mean by Lofenalac? Lofenalac is a formula which is nutritionally complete except for phenylalanine. This formula is the main diet for the infants suffering from

Steps of armamentarium, Armamentarium 1. Edentulous stock trays 2. R...

Armamentarium 1. Edentulous stock trays 2. Rubber bowl and alginate mixing spatula, plaster mixing spatula 3. Vernier calipers 4. Alginate impression material 5. Gy

Treatments of coronary, The treatment of hyperlipidemia requires two approa...

The treatment of hyperlipidemia requires two approaches: Therapeutic lifestyle changes (TLC) and medications. To achieve target LDL levels, most patients need both approaches si

What do you meant by medical writing, Question 1 : What do you meant by ...

Question 1 : What do you meant by medical writing? Show various types of medical writing. Define and explain briefly medical writing Discuss various types of medical w

Glands and its types, Glands A cell, tissue or organ which secretes ...

Glands A cell, tissue or organ which secretes specific chemical secretion is known as a gland. The glands develop from the epithelium tissues. The glands are classifi

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