-Ms. Neha Patni DEFINITION: Any combustible substance which is - - PowerPoint PPT Presentation
-Ms. Neha Patni DEFINITION: Any combustible substance which is obtainable in bulk, which may be burnt in atmospheric air in such a manner that the het evolved is capable of being economically used for domestic and industrial purposes for
DEFINITION: Any combustible substance which is
atmospheric air in such a manner that the het evolved is capable of being economically used for domestic and industrial purposes for heating and generation of power.
FUEL + O2 Products + Heat
Th The co compositio sition n of co coal l vari ries s acc ccord rdin ing g to the degree of coali lifi ficati ation. In order to co compar are e the coals ls for the consum umer er, , pri rize fix ixation tion and many y other er factors rs ,the analysi lysis s of co coal l is is carrie ied out Coal l analy lysis sis are of two ty types es :
1. 1.
Pro roxim imat ate e analysis lysis
2. 2.
Ul Ultim imat ate e analy lysis is
1.SUITABILITY: For instance , coke made out of bituminous coal is most suitable for blast furnace , inspite of the fact that charcoal or anthracite may also be used. 2.COST: The fuel should have a low cost and on prolong storage it should not change its properties significantly. 3.CALORIFIC VALUE: The fuel must possess high calorific value (heat per unit mass or volumes)and produces no hazardous gases which might pollute the atmosphere. 4.IGNITION TEMPERATURE OR KINDLING TEMPERATURE: The minimum temperature at which the substance ignites and burns without further addition of heat from outside . Fuel should possess a moderate ignition temperature . Too high ignition temperature causes difficulty in kindling while too low ignition temperature may create safety problems during storage , transport and use of the fuel . The presence of moisture and foreign material in the fuel always decreases the ignition temperature. 5.Flame temperature: The highest temperature at which an substance can be heated by flame is called flame temperature . The flame temperature generally increases with the increases in the number of combustibles.
6.MOISTURE: It should be very low. High moisture content lowers the
effective calorific value of the fuel.
7.NON COMBUSTIBLE MATTER CONTENT: The non combustible
matter forms clinkers after combustion and it reduces the heating value and involves the cost of disposal after the combustion.
8.VELOCITY OF COMBUSTION: Velocity of combustion should be
whereas too low velocities causes loss of heat due to radiation.
9.Control of the process: The fuel should be such that its combustion
can easily be controlled i.e. It can be easily started or stopped.
10.Ash: It should produce minimum quantity of ash upon
combustion . The Higher proportion of ash may have lower calorific values.
11.Sulphur and Oxygen: The fuel should have minimum quantity of
sulphur and oxygen because higher sulphur contents may create corrosion , while oxygen decrease ignition temperature .
12.Safety: It should be safe while transporting and storage. 13.Production of side products: It should not produce any
undesirable products(i.e. Noxious gas and pollutants) upon combustion which are harmful to the atmosphere.
G.C.V. (Gross calorific value) or H.C.V. (High
calorific value)
Definition : “Total amount of heat liberated
when unit mass bond and products are cool
G.C.V = N.C.V + LATENT HEAT. N.C.V (Net Calorific value ) or L.C.V (Low calorific
value)
Definition : “ Total amount of heat liberated
when unit mass of fuel bond and products are allowed to escaped.”
C= percentage of carbon H=percentage of hydrogen O=percentage of oxygen S=percentage of sulphur
Peat Lignite Sub-bituminous Bituminous Anthracite
Proxim imat ate e analysi lysis s is is a em empiri irical al rather er than n true analys ysis. is. It in inclu ludes des the determina mination ion of the foll llowi wing: ng:
1. 1.
Mois isture ure content ent
2. 2.
Vo Vola latil ile matter er
3. 3.
Ash Ash
4. 4.
Fix ixed ed carbon
Moistu
sture re content ent : Moisture sture content ent should
w. Reason son:
1. 1.
For eve very ry perc rcen ent of moisture ture presen esent 1% of heat t is lost.
2. 2.
Increa creases ses transport nsport cost. Ho Howe wever ver about ut 5-10% moistur ure e is desi sirab rable e as it prod
uces es a uniform form fuel bed and less s of fly ash. h.
Moisture sture co content tent is determined rmined by
1. 1.
Heati ting ng a k known wn quantit tity y of air-drie dried d co coal l to 105 105-11 110 0 C C for an an hour. r.
2. 2.
It is co cooled led and then n weighe hed. d.
3. 3.
Loss ss in weight ht of co coal l is reported rted as moisture sture co conten tent t on per erce centa ntage ge bas asis Percentage centage moisture sture= = (W-w) w) x 100 /W Wher ere, e, W=wei eight ght of sam ampl ple e bef efore
eating ing w= weight ht of samp mple le after r heati ting ng
VOLAT
Volati tile e ma matter er consi sists sts of a mi mixture ure of ga gaseo eous us and liquid id prod
ucts resu sulting ting from the e thermal rmal decomp mposi
tion
Eg : H2,CO, O,CH4 It does es not include ude mo moisture ture of coal. Volati tile e matter er must t be low. w. Reason: son:
1. 1.
A hi high h per ercentage centage of vola latile tile mat atte ter r indicates icates that at a l large e part fuel is burnt nt as a g gas which ch may y esca cape pe unburnt urnt.
2. 2.
Higher her volati atile le matter ter means ns more e smoke
more e polluti lution
%C= (12/44)*(
)*(x/w x/w)*10 )*100
%H=
H=(2/1 2/18)*(y/w)*10 8)*(y/w)*100 (where, x=weight of CO2 absorbed y=weight of H20 absorbed w=weight of original sample)
It is determine ned d by:
1. 1.
Heating ng a known wn weight t of mo f moistu ture re fr free coal at around nd 950 C fo for 7 minutes. s.
2. 2.
It is then cooled. d.
3. 3.
Loss in we weight t is reporte ted d as volatile ile ma matter. r. Percenta tage ge volatil ile e matter =(x-y) ) X 100 / w where re x=weight ght of t f the sample befo fore heating ng y=w =weight ht of f samp mple aft fter heating ng
ASH
Ash h usual ually ly consists sists of sili lica, a, alumina, ina, iron n
e and small l quanti antiti ties es of lime, magnes nesium ium etc. Ash h content ent shoul
d be low. w. Reason: son:
1. 1.
It red educes uces calori rifi fic c va value. e.
2. 2.
In furnac rnace e gr grate, te, the ash h may restric strict t the passage ssage of air and d lowe wer the rate e of comb mbus ustion ion.
It is determined ermined by :
1. 1.
He Heating ing a known wn we weigh ght t of coal sampl ple e at 75 750 C fo 0 C for about ut 1 h 1 hour. ur.
2. 2.
The remaining maining mass ss is then n cooled d and d we weigh ghed ed.
3. 3.
The remaini aining ng mass s in terms rms of perc rcen entage age is repo ported rted and ash h content. ent. Pe Percentage centage ash= h= z X 100/ W Where re z=wei weight ght of resid sidue ue left W= W=we weight ight of coal sampl mple. e.
FIXE
Fixed d carbo bon n content ent must t be high gh. Reason son :
1. 1.
Hi High gher er fixed ed carbon bon content ent me means ns gr great eater er calori rifi fic va value. e. Pe Perce centage ntage of fixed ed carbon bon = 100 100 – [% moisture ture + %vo volatil atile e matter er + %ash] sh]
The ‘ultimate analysis’ gives the composition of
the biomass in weight percentage of carbon, hydrogen and oxygen (the major components) as well as sulphur and nitrogen (if any).
Helps determine if the fuel is good for a
particular application (as opposed to proximate analysis that gives only the general usability of a fuel).
Also called ‘Elemental Analysis’.
Required for detailing and accurating heat
balance for equipments in which coal is used
Useful in estimating calorific value of coal Used in designing furnaces
The ultimate ate anal alysi ysis s determ ermines ines the elemental ental anal alysis sis of the fuel sample e like :
1. 1.
Carbon rbon
2. 2.
Hy Hydro drogen gen
3. 3.
Sulphur phur
4. 4.
Nitroge gen n
5. 5.
Oxygen. gen.
A known mass of organic compound is
heated in the presence of pure oxygen. The carbon dioxide and water formed are collected and weighed. The percentages of carbon and hydrogen in the compound are calculated from the masses of carbon dioxide and water.
Leibig’s Apparatus
PROCED EDURE URE :
A known
unt of coal( ( x gm gm) Is taken en in a comb mbus ustion ion tube e and d burn rnt in ex excess ess of
gen(no C02 or moisture).The ture).The hydrog drogen en and d carbon bon are convert verted ed into H2O and CO2.
2.
C(s) s) + O2(g) g) CO2(g) g)
gm 2 X X 16
gm 44
gm
H2 + ½O
½O2(g)
g) H2O
gm 16
gm 18
gm
The other er oxidatio ation n produ ducts cts sulph lphur ur(S) (S) and d chlorine(Cl rine(Cl) ) are e also obtai ained ned wh which h are trapped pped by silver ver ga gause se heated ated at 800-850 C, wh while CO2 and H2 H2O are e abso sorbe rbed d in pre- we weigh ghed ed KOH H soluti ution
d anhydrous hydrous CaCl2. 2.
2KOH
H +CO2K2CO CO3+ + H2O
CaCl2 +
+ 7H2O O CaCl2.7H2O
Let, Weight t of coal sample=w le=w gm Increase crease in weight t of CaCl2=y =y gm gm Increase crease in weight t of KOH=x =x gm
gm of CO2 = = 12
gm of C Y gm of CO2 =(12/4 /44) 4) X y gm gm of carbon bon Therefore, refore, % carbon=
(12/4 2/44) ) X (x X 100)/w /w Similarly, arly, % hydrogen= drogen= (2/18) ) X (y X100)/w /w
Greater the percentage of carbon, greater the
calorific value
Higher percentage of carbon reduces the size
Higher percentage of hydrogen also increases
the calorific value of the fuel.
The e nitrogen rogen cont ntent ent pres esen ent t in coal l is es estimated ted by Kjeldahl’s met ethod. d. Proce cedu dure re:
A known
wn weight ht of coal al sample long g with h K2SO SO4 + H HgSO4 is taken which acts s as a catalyst t is heated d with conc. . H2SO4.
Nitrogen
d into (NH4)2SO SO4.
The content
ents s are then transferr erred into
sk and the cont ntent ents s are then heated ted with h excess NaOH.
The NH3 gas thus
us liber erat ated ed is absorb rbed ed in a known
ume
d acid. d.
The unuse
sed acid d is then determined d b titrating ng with NaOH.
From
m volume ume of acid used by N NH3 , nitr trogen gen con
tent can n be e calcula ulated. d.
(NH4)2SO
SO4 + + 2NaOH H Na Na2SO SO4
4 +
+ 2NH NH3 + + 2H2O
NH
NH3 + H2SO SO4 (NH4)2SO SO4 Let, , we weigh ght t of coal sample ple = W g W gm Volume me of acid d used= ed= V1 ml Normal alit ity y of the acid = N1 V1 ml of N1 acid= = V2 ml of N2 NH3 V2 ml of 1N NH3= V1 X N1 ml of acid Bu But 1000 ml of 1 N am N ammoni nia a soluti ution=
g of NH NH3=14g g of nitro roge gen Th Therefore, erefore, V2 ml 2 ml of 1 n 1 normal mal amm mmoni nia a soluti ution
= = (14 X N1 X V1)/100 1000 Pe Perce centage ntage nitrogen=(1 rogen=(1.4 .4 X N1 N1 X V1) 1)/W /W
Procedur
e:
Sulphu
phur prese esent nt in the coal al is oxidize dized d by fumi ming ng nitric tric acid d and sulp lphur huric ic acid id.
The sulphur
lphurin inc acid id is preci ecipita pitated ted as Ba BaSO SO4 by addi dition tion of BaCl Cl2.
The preci ecipitate pitate of BaSO SO4 is filter ered ed and heate ted d to a const nstant ant weigh ght. t.
From
e weight ght of BaSO4,sul ,sulphu phur r content ntent is calculated culated. Let, , Weig ight ht of coal al sampl ple= e= W gm the he mass s of preci ecipitate pitate = x gm 23 233 3 gm m of Ba BaSO SO4 = 32 32 g of sulphur lphur W gm of BaSO SO4 = (32/233 /233) gm Percent centage ge of sulp lphu hur r = (32/23 233) 3) X (x/W) W) X 100
ASH:-
It is determined in the same way as in proximate analysis.
DETERMINATION OF OXYGEN:
The percentage of oxygen can be calculated by deducting the percentage of all the element present in the coal from 100 by using following formula. % of oxygen = 100 – [% C + % H +% N + % S + % Ash]
Significance : Less is the oxygen content better is the coal. Oxygen is in combined form with hydrogen in
coal and thus hydrogen available for combustion is lesser than the total hydrogen present.
PROXI OXIMATE MATE ANALYS YSIS IS : RE REVISI SION ON
Ultimate analysis : Revision
The mixture of Carbon dioxide, Carbon monoxide
and Oxygen releasing out of combustion chamber is known as flue gases.
Analysis of flue gases gives idea regarding the
efficiency of the combustion process.
1.
More carbon monoxide content in flue gases indicate that oxygen supply is less and combustion is Incomplete.
2.
If there high percentage of oxygen , it indicates that combustion is complete but the supply of oxygen is excessive.
3.
If there is high percentage of carbon dioxide , it indicates proper combustions of fuel and adequate supply of oxygen.
E -Entrance for flue gas. U -contains glass wool for, retaining moisture and smoke. V -three way stopcock. S1,s2,s3 -are stopcocks connecting to bulbs b1,b2,b3 respectively.
FLUE GAS ANALYSIS by ORSAT’s APPARATUS
Absorpti tion
Bulb Solutio ion n Filled Functi ction
B1 Ammonical Cuprous Chloride (100 gm CuCl + 125 ml liq. NH3 +75 ml H2O) It can absorb CO,O2,CO2 B2 Alkaline Pyrogallic acid (25 gm Pyrogallic acid + 200 gm KOH + 500 ml H2O) It can absorb CO2,O2 B3 Potassium Hydroxide Solution (200 gm KOH + 500 ml H2O) It absorb CO2
Dif iffer ferent ent So Solu lutions ions filled led in bul ulbs bs of
sat t Appar arat atus us
and tested for air tightness. Solutions are filled in bulbs as per
separating funnel and fill water in gas burette.
funnel so water will run to B3 and suck the required quantity of water and close the valve.
separating Funnel till glass bulb is filled with water. Connect V and E and allow the Gas to be analysed in glass tube.
amount of air in glass tube and untill exactly 100ml of gas at atmosphere is collected.
SF to Get gas in GB and repeat till complete absorption of CO2 in KOH .
and then
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BIODIESEL ETHANOL HYDROGEN METHANOL NATURAL GAS CNG LNG LPG
Biodiesel is a domestically produced, renewable fuel that
can be manufactured from vegetable oils, animal fats, or recycled restaurant greases.
Biodiesel is safe, biodegradable, and reduces air
pollutants such as particulates, carbon monoxide, hydrocarbons, and air toxics.
Biodiesel can also be used in its pure form but it may
require certain engine modifications to avoid maintenance and performance problems and may not be suitable for wintertime use.
Need to heat storage tanks in colder climates to prevent
the fuel from gelling
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IT IS ALCOHOL BASED FUEL
PRODUCED BY FERMENTING AND DISTILLING STARCH CROPS.
ETHANOL PRODUCED FROM
CELLULOSIC BIOMASS SUCH AS TREES AND GRASSES IS CALLED AS BIOETHANOL.
E85,E95,E10 ARE USED AS
FUELS IN VEHICLES.
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Gasoline with ethanol is still gasoline. It's not an alternative fuel. An increasing number of new vehicles can use E85 (15% gasoline,
85% ethanol), which is an alternative fuel.
Methanol, also known as wood alcohol, can be
used as an alternative fuel in flexible fuel vehicles that run on M85
The benefits include lower emissions, higher
performance, and lower risk of flammability than gasoline
Methanol can easily be made into hydrogen for
hydrogen fuel cell vehicles in the future.
Methanol is extremely corrosive, requiring special
materials for delivery and storage.
H2 HAS BEEN USED EFFECTIVELY IN A NUMBER OF INTERNAL
COMBUSTION ENGINE VEHICLES AS PURE H2 MIXED WITH NATURAL GAS.
H2 AND O2 FROM AIR FED INTO A PROTON EXCHANGE
MEMBRANE(PEM) FUEL CELL”STACK” PRODUCE ENOUGH ELECTRICITY TO POWER AN ELECTRICITY TO POWER AN ELECTRIC AUTOMOBILE,WITHOUT PRODUCING HARMFUL EMISSIONS.
TWO COMMON METHODS TO PRODUCE H2 ARE:
(I)STEAM REFORMING OF NATURAL GAS (II)ELECTROLYSIS OF WATER
IT HELPS IN: (I)ENERGY SECURITY (II)GLOBAL CLIMATE CHANGE (III)AIR QUALITY
placed in a series to form a fuel cell stack
system to power a vehicle.
speculate that a fuel cell vehicle will be commercialized soon.
use in North and South America, Europe, Asia and Australia.
forklifts and even bicycles are utilizing fuel cell technology as well.
NATURAL GAS ARE DOMESTICALLY
PRODUCED,HAVE CLEAN BURNING,AND HAS LESS HARMFUL EMISSIONS.
IT IS THE MIXTURE OF HYDROCARBONS
MAINLY CH4 AND IS PRODUCED EITHER FROM GAS WELLS OR IN CONJUCTION WITH DRUDE OIL PRODUCTION.
SMOG PRODUCING GASES SUCH AS CO AND
Nox ARE REDUCED BY 90% AND 60%.
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Still a major contributor, despite reductions in new vehicle emissions achieved over the last decade
CO NOx Lead VOCs CO2 Particulates 79% 53% 13% 44% 33% 25% SO2 7%
LNG IS ALMOST PURE METHANE AND BECAUSE
IT IS A LIQUID HAS AN ENERGY STORAGE DENSITY MUCH CLOSER TO GASOLINE THAN CNG.
IT IS TYPICALLY USED IN HEAVY-DUTY
APPLICATIONS SUCH AS TRANSISTS BUSES,HEAVY DUTY,LONG-HAUL TRUCKS OR LOCOMOTIVES.
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CNG is made by compressing natural gas which is mainly
composed of methane, to less than 1% of the volume it
CNG HAS LOW HYDROCARBON EMISSIONS AND
VAPOURS ARE NON-OZONE PRODUCING.
CNG IS 70%-90% METHANE
10%-20% ETHANE 2%-8% PROPANE AND DECREASING QUANTITES OF HCs UP TO PROPANE.
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ALSO KNOWN AS BOTTLED GAS OR
REFINERY GAS WHICH IS OBTAINED AS A PRODUCT DURING THE CRACKING OF HEAVY OILS OR FROM NATURAL GAS IS PREDOMINANTELY PROPANE WITH iso- BUTANE AND n-BUTANE.
LPG CONSISTS OF HYDROCARBONS OF SUCH
VOLATILITY THAT THEY CAN EXIST AS GAS UNDER ATM. PRESSURE BUT CAN BE READILY LIQUEFIED UNDER PRESSURE.
Propane or liquefied petroleum gas (LPG) is a
popular alternative fuel choice for vehicles because there is already an infrastructure of pipelines, processing facilities, and storage for its efficient distribution.
LPG produces fewer vehicle emissions than gasoline. Propane is produced as a by-product of natural gas processing
and crude oil refining.
The cost of a gasoline-litre equivalent of propane is generally
less than that of gasoline.
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CNG
More economical Kit more expensive More wear and tear on
engine
Safer in case of leakage-
lighter than air
Does not contaminate and
dilute the crankcase oil LPG
Higher Calorific Value Easily Available Wears out piston heads with
heavy loads
Stored at lower pressures Non-corrosive and free of
tetra-ethyl lead or any additives
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