How water is treated for the municipal supply ?

water treatment for municipal supply 

As the topic suggests treatment of water for the municipal supply here we’ll study how the municipal authority treated water before the supply of the water. We will know about the various methods which are used by the municipal authority for the treatment of water.

so let's begin with the introduction and then after we’ll go through the methods.

The water which is supplied to our home from municipal water supply is a source of natural water. which is obtained from rivers, canals, wells, etc. 

as it does not fulfill the required quality standards prescribed by the government so this nature is not good for the supply.

So for that to make this water suitable for the municipal supply some treatments are required for the supply of this water which depends upon the exact nature of impurities present in raw water. 

 Below given are the methods which are performed by the municipal authority for the treatment of water before supplying towards our home. 

1. screening 

2. sedimentation 

3. sedimentation with coagulation 

4. filtration 

5. disinfection 

I hope you have got some idea about the municipal water supply in another blog we’ll discuss these methods in detail 

thankyou and have a amazing day 

BY :- ADARSH GUPTA 

What is lubricants?

lubricants :- 

lubricant is a kind of substance which is used to minimise the friction of the two continiously moving body.

in any type of mechinery due to the presence of moving parts there is constant rubbing of the surface of the moving parts of the mechinery this resistance between the mechinery is known as friction.  

this friction is not good for the life of the mechinery hence it casuses wear and tear to the parts of mechine which also afecs the life and efficiency of the mechinary.

the friction inside the rolling or movin parts in the mechinary not only causes the wear and trear of the moving parts of mechine but also release a large amount of heat energy which effects the efficiency of the mechinery 

to minimise the friction between the moving parts of mechine some substence are inceeted between the moving parts of he mechinery to reduce the friction of the mechine these substance forms the thin layer in between two moving or sliding bodies by application of lubricants betweeen them is known as lubrication

in another words we can say that the substance which is introduced between the moving and silliding mechinery parts to reduce the frictional resistance between to fix the problems of wear ad tear in the moving mechinery parts 

and the process of reducing the friction in between the rolling and silliding parts of mechinery to overcome with the problem of wear and tear is known as lubrication 

as we know the surface of metal which is used in the mechine are never perfectly smooth and the have a irregularities in the form of elevation(which is the peak point) or depression (which is valleys) at the microscopic level 

when the moving metal surface came in the contact during moving of these metal parts, these parts gets rubbed against each other the asperties get welded due to the local mealting and some energy has to be spent to break the welded junction 

the asperties begins deforming and flattening out. this causes the formation of weed junctiojns ploughing or cutting out the softer material by the aspeties of the harder materials and the interlocking of the surfqace irregularities.

this friction produces due to the irregularities of the rolling and slidding metal surface this may cause damage to the mechinery in three ways 

1. heat generation :- 

the irregular surface of the rolling and sliding metals cause the production of huge friction and this friction leads to the generation of heat in the large amount and these produces heat may change the shape and size of the machinery parts which causes deformation of the machines 

2. energy loss :- 

this is another problem that arises due to friction. the power which is supplied to the machinery doesn't convert totally into the work some amount of energy is lost in terms of heat or in other form and which is determined as the energy loss

 

3. material loss :- 

the next disadvantages of the friction which is produced inside the machine is the loss of materials of the moving or sliding parts of the machinery and due to the difference of the hardness of these moving bodies leads to the lost of the materials 

function of lubricants :- 

as we see above the working of the lubricants and the requirements of the lubrication inside the machinery

now we will see the functions of the lubricants 

1. the very first function of a lubricant is it reduces the friction inside the machinery 

2. As we see above, it forms a thin layer over the rolling or sliding surface so it prevents the direct contact of these rubbing surfaces so that it reduces the wear and tear and surface deformation. by this it cure the machine from maintenance cost 

3. it also works as a coolant and prevents machine from heating effect 

4. By reducing the heating effect it prevents the expansion of metal by local frictional heat. 

5. it avoids the seizure of moving surfaces that's why the use of lubricant reduces the liberation of frictional heat 

6. also it makes the movement much smooth relatively 

7. it absorbs shocks between bearing and and in the moving parts of engine and contributes in reducing the noise of the machine 

8. also in an internal combustion engine it ac as a seal by sealing the piston and cylinder at the compression ring by this it protects the leakage of gasses at the high pressure in the compression chamber 

9. The lubricant also carried away the contaminated products from the rear parts of the machine so they may be removed from the system by oil draining or by oil purification system. 

so above we get the knowledge about the lubricants and also we come to know about the various different applications of lubricant. 

BY :- ADARSH GUPTA 

What are boilers ?

What is a boiler ? What is the use of a boiler ? where the boilers are used ? 

At the end of this study you will get the knowledge about the boilers, its use and its working , etc.

Let’s begin with the introduction of boiler so a boiler is a very essential engineering material which is used in the production of steam in the various power plants for the production of electricity by rotating the turbine blades of the power houses 

Water is very essential in this process because for the production of steam water is heated inside the boiler and converted into the steam the water which is used in the boiler for the production of steam is known as boiler feed water

Because water is a essential unit inside the boiler there is certain requirement are required for the water to reach the requirement of the boiler like the water which is to be used in the boiler should be free from the dissolve salts(calcium and magnesium salts) also it should not contain gases such as oxygen and carbon di-oxide 

The composition which is required for the boiler feed water are as follows :- 

1. The hardness of the water should be below 0.2ppm

2. It's caustic alkalinity should be 0.15 - 0.45 ppm 

3. It soda alkalinity should be lie between 0.45 - 1.0 ppm

4. Excess soda ash should be between 0.3 - 0.55 ppm 

Hear ppm stands for parts per million which is a measuring unit of the solution. 

Also the composition of the boiler feed water varies as per the pressure requirement of the steam. 

The constituent limit of the boiler feed water is checked regularly because the unawareness of the constituent of the boiler feed water may lead to the problems inside the boiler such as priming, foaming, carry over, boiler corrosion, scale and sludge formation, caustic embrittlement these problems inside the boiler may lead to the serious explosion also. 

Uses of boilers :- 

Today boiler plays an important role in almost every unti by producing power

 

The power generated by the boilers are used by many industries to running machinery and many industrial equipment runs by using this power source 

boilers fulfills all the basic requirements of the industrial machinery by producing electricity for them 

Also the power produced by the boilers are used for the domestic purposes like as electricity supply to the houses 

On the other hand it is also used in the cold areas to supply warm water through pipelines

Besides this it has many other uses of boiler.

I hope the above mention help you to learn about boilers 

Thankyou 

BY :- ADARSH GUPTA

How boilers are effected by corrosion ?

What is boiler corrosion? How did a boiler get corroded?

The process of decaying or disintegration of boiler material either by a chemical or electrochemical reactions with its environment is known as boiler corrosion 

Causes of boiler corrosion :- 

The causes of boiler corrosions are as follows

1. Due to the presence of dissolved oxygen :- 

As we know that the water which is feed to the boiler contains some amount of oxygen as well as usually it contains about 8ppm of dissolved oxygen at the room temperature 

When the water inside the boiler is heated then dissolved oxygen in the boiler feed water is also get heated due to the heating of dissolved oxygen of water it evolves some gases which becomes the reason of corrosion inside the boiler 

2. Due to the presence of carbon dioxide :- 

As we know that the natural water also contains some amount of carbon dioxide in it but also it may be released inside the boiler during the process of generation of steam.

3. Due to the presence of acid forming salts :- 

The inner walls of boiler may also be corrode due to the presence of some acid forming salts inside the boiler which comes along with the boiler feed water 

Water which is used for the boilers contains chlorides of magnesium and calcium in it which hydrolysed to form acids and which has corrosive action on the boiler material 

Where as magnesium chloride present in boiler feed water hydrolysis completely at 200`C to form hydrochloric acid 

At last the liberated acids react with the boiler material (which is iron) in a chain like reaction producing hydrochloric acid repetitively which causes extensive corrosion. 

Here calcium chloride also goes hydrolysis but to a lesser extent.

It hydrolyse to an extent of 25% at 600`C silicic acid catalyses the reaction therefore if water contains contains silica than an appreciable quantities of HCL may be formed even at the lower temperature 

And this type of corrosion in the boiler could be prevented by adding alkali to neutralize the acid which is formed inside the boiler 

4. Formation of galvanic cells :- 

The boiler may also corrode due to the formation of galvanic cells between the iron and other metal present in the alloy used in boiling fitting; this may also lead to boiling pitting corrosion. 

This type of corrosion can be prevented by suspending zinc plates which act as a sacrificial anode inside the boiler 

I hope the above mentioned information helped you to understand about the causes of corrosion occurring inside the boiler. 

thankyou 

BY :- ADARSH GUPTA 

How the boiling of water is helpful for good health

HOW BOILING OF WATER IS HELPFUL FOR OUR HEALTH ?

The boiling of water is a one of the best method of killing harmful bacteria from water which can be practice at home without any chemicals 

This method can be practice easily at our home 

The harmful disease producing bacteria which is present in the water can be killed easily by simply boiling the water for approximately 15 - 20 minutes.

LIMITATIONS OF THE PROCESS 

The boiling method is capable to kill the harmful bacteria of water but the method has some limitations with them which we will discuss below 

• The boiling method is costly thats why this method is not much suitable for the municipal supply but this method can be practice at individual level 

• The boiling method of water ensures to kill the bacteria present in the water at the time of boiling of water but it does not provide any protection for the further contamination 

• During the boiling process the fuel is used for boiling which is again not a good method 

The boiling method of water is used for a long time in tradition of indian people which is much beneficial for the good health 

It also increases the immunity power of the human body 

I hope the above mentioned information about the boiling method helps you to know about the method by which you can ensure the quality of water which you will be drinking 

It'll be very beneficial and helpful method for you 

Thankyou 

BY :- ADARSH GUPTA

What is priming, foaming and carrying over

What is priming, foaming and carrying over ? What are their disadvantages ? 

Priming, foaming and carryover all these phenomena occurs inside the boilers due to the improper composition of the boiler feed water. 

When the steam is produced rapidly inside the boiler at this time some small droplets of water are also carried along with the steam.

The steam which carries the water droplets along with them is known as wet steam which creates problems inside the boiler.

1. Priming :- 

priming is the process of formation of wet steam inside the boiler the phenomena occurs inside the boiler due to the rising of water in the boiler due to foaming. 

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Causes of priming :- this phenomenon inside the boiler occurs due to the certain reasons such as presence of large amount of dissolved solids in the water, very high level of water inside the boiler, high steam velocity, improper designing of boiler, and due to sudden increment in the production rate of steam which leads to the sudden boiling.  

Steps required for the prevention of priming :- 

-> by the use of mechanical steam purifier 

-> by keeping the water level lower 

-> by controlling rapid changes in the rates of steam

-> by using a proper boiler design

-> by using efficient softening and filtration of boiler feed water 

-> by blowing off sludge or scales from time to time

2. Foaming :- 

The phenomenon of formation of foam and bubble on the surface of water inside the boiler is called as foaming which becomes rigid by the time and did not break easily 

Causes :-

The process of foaming in the boiler feed water generally happens due to the presence of oil, grease, and alkalis in water and these substance reduces the surface tension of the boiler and causes foaming 

it may also cause due to the presence of finely divided sludge particles in the boiler feed water. 

Prevention method of foaming :- 

It can be prevented by adding coagulants like ferrous sulphate, sodium aluminate etc. because it removes oil,grease and finely sludge particles from boiler feed water. 

Another prevention method is by adding anti-foaming agents like caster oil spreads on the surface of water and neutralises the surface tension of the boiler feed water. 

Disadvantages of priming and foaming :- 

Priming and foaming often affects the efficiency of the boiler we have seen some of its disadvantages above now we will see some other disadvantages of priming and foaming 

-> due to the presence of water droplet in the steam may lead to the corrosion in the steam inlet ends of super heater it appears as a serious problem in the biollers because the replacement cost of the tube is huge  

-> height of the water column cannot be judged properly due to the foaming making also it affects the maintenance process of the boiler 

-> a part of dry salts may be carried along with the steam farther and deposits on the engine valves thereby decreasing their life 

3. Carry over :- 

The phenomenon of carrying water along with impurities by steam is called “carry over” ; this phenomenon mainly occurs due to priming and foaming.

the phenomena of priming and foaming usually occurs together and the  are objectionable because

• Dissolved solids or suspended solids in water carried by the wet steam to superheated and to the turbine blades and they get deposited over the blades of the turbines which decreases the efficiency of the boiler.

• Dissolved salts may enter to the parts of other machinery and then decrease their life. 

• The maintenance of the boiler pressure becomes difficult because of improper judgement of actual height of water. 

I hope the above mentioned information helped to gather knowledge about the phenomenon which occurs inside the boilers 

Thankyou

BY :- ADARSH GUPTA  

       How to determine the hardness of water

By edta method / complexometric method :- 

EDTA stands for ethylenediaminetetra acetic acid This method is widely used for the determination of hardness of water because it is more accurate than the soap titration method.

edta is a strong complexing agent.

as edta is not soluble in water but it is soluble in disodium salt so it is generally used in complexometric titration.

the complexing property of edta is used to estimate the amount of hardness causing ions in the water sample.

so that the water sample buffered at PH=9 to 10 is titrated against EDTA using eriochrome black-T which is also known as EBT indicator 

EBT (eriochrome black-t) indicator is a blue coloured azo dye which is capable of forming soluble wine-red coloured complexes with calcium and magnesium 

principle :- 

 This method is based on the fact that bivalent hardness causing metal ions (calcium and magnesium ion) which is present in the hard water is able to form complexes with both eriochrome black-t (ebt) as well as ethylenediaminetetraacetic acid (edta).

but the edta complexes are more stable as compared to ebt indicator

1  When ebt indicator is added to the sample of hard water then it forms a wine red colour compound which is a unstable compound

2  On addition of edta it first combines with free metal ions to give very stable and colourless metal ion-edta complex then the metal ion indicator comlex

3  When all the free metal ion gets complexed with edta further addition of edta solution displace the ebt indicator from metal-ebt complex since the stability of complexes (metal-edta) is very high than metal-ebt complex

now the free indicator shows blue colour in solution at ph=9 to 10 so that at the end point of the titration the colour of the titration turns wine red colour to blue colour

calamite is also use as indicator because of behaviour is identical to eriochrome black-t 

thus the amount of edta used corresponds to the total hardness of water.

but the temporary hardness of the water can be easily removed by simply boiling of water and after the removal of precipitate by filtration the permanent hardness of the water can be determined by the titration and temporary hardness will be given by the difference of total hardness and permanent hardness.

Procedure :- 

Preparation of solution :- 

1. preparation of standard hard water :- 

For the preparation of shw (standard hard water) dissolve one gram of pure and dry calcium carbonate in minimum quantity of of dilute hcl and boil it 

this solution is evaporated to dryness to remove excess of hcl and co2 

the residue is dissolve in distilled water and make up the solution upto one litre

 

2. preparation of edta solution :- 

For the preparation of edta solution dissolve 3.72g of disodium salt of edta in distilled water and make up to 1000ml, 0.01m edta is prepared.

3. preparation of buffer solution :- 

For the preparation of buffer solution for the process weight out of 67.5 g of NH4CL and dissolve this in 570 mL of concentration ammonia solution and make upto 1 litre with distilled water.

 

4. preparation of eriochrome black-t solution :-

 For the preparation of eriochrome black-t solution you need to dissolve 0.5 g of eriochrome black-t on 100mL of alcohol

Determinations of hardness :- 

1. standardization of EDTA method :- 

for this you need to fill up the burate with the edta solution. pipette out 50 mL of standard hard water into the conical flask. then after you need to add 10 mL of buffer solution of pH value across 9-10 and add 2-3 drops of eriochrome black-t. titrate this solution against EDTA until the wine-red colour, changes to blue (due to EBT) 

for the calculation purpose let the value of EDTA used in the process be V1 mL. 

2. determination of total hardness :- 

It also follows the same procedure which is mentioned above, then after titrating 50 ml of unknown water sample against EDTA. let the volume of EDTA used this time will be as V2 ml. 

3. determination of permanent hardness :- 

For the determination of permanent hardness you need to take 250 ml of the water sample in a 500 ml and you have to boil it till the volume reduce to about 50 ml and also this step causes all the bicarbonates decomposes into insoluble calcium carbonate and magnesium hydroxide. filter and wash the precipitate with distilled water and quantitatively collect the filtrate and washing in 250 ml conical flask and make up the volume to 250 ml with distilled water. titrate 50 ml of this water sample against EDTA and also let the volume used here be V3 ml. 

While performing this process in a chemistry laboratory you need to take care of certain precautions for the successful completion of the reaction. 

and also it is required to perform actions in the guidance of a lab assistant or some faculty member.

I hope the mentioned above information helps to getting much knowledge about the hardness of water 

Thankyou and have an amazing day. 

BY :- ADARSH GUPTA