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

Flow cytometry, The following histograms were produced using flow cytometry...

The following histograms were produced using flow cytometry after labelling B-cell lymphocytes with propidium iodide. Histogram A is from a healthy individual while Histogram B is

Types of drug action, TYPES OF DRUG ACTION - 1 .       PHARMACODYNAMI...

TYPES OF DRUG ACTION - 1 .       PHARMACODYNAMIC DRUGS - These drugs modify the physiological and biochemical processes in the patient's body to eliminate the disease.

Explain cholera, Cholera  The risk of infection with cholera is very lo...

Cholera  The risk of infection with cholera is very low in tourists. The parenteral vaccine licensed in the US is no longer available. One oral vaccine called Dukoral is availa

Define the term - soil heterogeneity, Define the term - soil heterogeneity ...

Define the term - soil heterogeneity The ratings seem rather arbitrary and empirical but are meant to get a reasonable yield. Outputs for different doses of fertilizers are obt

High energy fixation - nitrogen fixation, High energy fixation - Nitrogen F...

High energy fixation - Nitrogen Fixation Through cosmic radiations, lightning, volcanic activity and meteorite trails which provide the high energy needed to combine atmospher

What do you understand by dimorphic nuclei, What do you understand by Dimor...

What do you understand by Dimorphic nuclei? Organization of the nuclear material typical of ciliates. There is always a single small micronucleus and either one large or many m

Observation of the anatomical structures, This assignment was done, sent in...

This assignment was done, sent in marked then sent back to me to be resubmitted. Comments were grammar & structure to be reviewed so could you please proof read & make it more acad

Define the clinical success for the root canal treatment, Define the Clinic...

Define the Clinical success for the Root Canal Treatment a) Absence of pain and swelling. b) Disappearance of sinus tract. c) No evidence of soft tissue destruction, incl

Define the term epimerism, Define the Term Epimerism? In addition to D ...

Define the Term Epimerism? In addition to D and L isomerism sugars also exhibit epimerism. Hexoses that differ from each other as a result of variation of H and OH on carbons 2

Infective endocarditis, Infective Endocarditis It is an infection of...

Infective Endocarditis It is an infection of the endocardial surface with micro organisms present in the lesion. The endocardium is contagions with the valves of the heart.

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