pr-sof-1262-design and fabrication of wood gasification plant that runs a 15 kva static load...

8/10/2019 Pr-sof-1262-Design and Fabrication of Wood Gasification Plant That Runs a 15 Kva Static Load Generator

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DESIGN AND FABRICATION OF WOODGASIFICATION PLANT THAT RUNS A 15 KVA

STATIC LOAD GENERATOR

PROJECT REPORT

DE-31 (DME)

Submitted by

GC-UMAIR SAEED

PC-M.ADIL NASEER

BACHELORS

IN

MECHANICAL ENGINEERING

YEAR

2013

PROJECT SUPERVISOR

Dr AAMER AHMAD BAQAI

COLLEGE OFELECTRICAL AND MECHANICAL ENGINEERING

PESHAWAR ROAD, RAWALPINDI

NUST COLLEGE OFELECTRICAL AND MECHANICAL ENGINEERING

DE - 3 1

( DME )


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DECLARATION

We hereby declare that no portion of the work referred to in this Project Thesis has been submitted in support of an application for another degree or qualification of this of anyother university or other institute of learning. If any act of plagiarism found, we are fullyresponsible for every disciplinary action taken against us depending upon the seriousness ofthe proven offence, even the cancellation of our degree.

3. Copyright Certificate

COPYRIGHT STATEMENT

Copyright in text of this thesis rests with the student author. Copies (by any process) eitherin full, or of extracts, may be made only in accordance with instructions given by the authorand lodged in the Library of NUST College of E&ME. Details may be obtained by theLibrarian. This page must form part of any such copies made. Further copies (by any

process) of copies made in accordance with such instructions may not be made without the permission (in writing) of the author.

The ownership of any intellectual property rights which may be described in this thesis isvested in NUST College of E&ME, subject to any prior agreement to the contrary, and maynot be made available for use by third parties without the written permission of the Collegeof E&ME, which will prescribe the terms and conditions of any such agreement.

Further information on the conditions under which disclosures and exploitation may take place is available from the Library of NUST College of E&ME, Rawalpindi.

Abstract


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4. Biomass fuel 235. Design and Fabrication 286. Analysis 377. Field-testing and results 648. References 69

Chapter 1 History and Background

Earlier Development:In 1798 Gasification process was discovered in France and England independently and till 1850 thistechnology was developed to such point that it was possible to light much of United Kingdom withthis Producer gas.During World War I small gassifiers were developed to operate vehicles, trains,


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ow india io 250kw),i

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organizatioeginning cy 2009 thi

of the TsunCurrent po

ow later iiomass gasrocess is

fabricatedaestimated th

he countryfirst Bioma

ake Imber

enerators.o operate vm of alternaicles werehicles thatoil embarg

s that wasca

e under devoducer gasting, In Braat.ow our futen place dh wood gaeminated in

ve brief loo.Uptill now

, Delhi,Indin Institute.In 1990s fid at apex li

s exportingdustries haindia emer ing project.It took one

leaning systs small scalmi relief.sitions:

2012 mor ification plaot only li

d giving bat small sca like Pakists gassifier.

t downdraft

uring thehicles.Duri

tive fuel du being powe

ere operateo of 1973 trried out to

eloped counfrom char

zil 30 large

ure conditiring world

ssifier vehiformation o

upon theour neighbn Instituteof Scien

rst small scit.

gassifier pve been dee as one ofin Sri Lan

year in ordem had a ne gasifier h

than 300Mnt was deveited to undnefit not o

le gassifiern, which isDrManzoogassifier .

ear 1939 ing the Wor e to shortagred by Synd on Produce united sta do researc

tries continoal was d units were

n, our priowar era inles were d small gass

ontributionours have cof Technole, Bangalle gassifier

wer plantseloped,res

the leadinga(small scr to contro

umber of pd been wor

W plants wloped.It is ter develop

ly to indiviving relieffacing dras Ahmad Pe visited th

Europe apld War IIer of conventgas and at

er gas.testoped wo and devel

ed to work veloped indeveloped

ities changhich transp

eveloped,duifier in case

of under derossed thegy, Bombare these awas develo

pto 250kwarch on clecountry inle gasifier l soot and taoblems butking well .

ere develope biggest bountries, Iidual but ato their natiic shortfallof at Unive university

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in which pr

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eloped couilestone in, Indian Inll dedicateed but afte

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Lignin(complex chemical compound,integral part of secondary cell wall of plant andmost abundant organic polymer on Earth)

complete flow sheet of biomass conversion into different fuelcellulose:

Hemicellulose:

Lignin:

complete flow sheet of biomass conversion into different fuel


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Thermal conversion process for biomass involve following reactionPyrolysis:

biomass+ heat charcoal+oil gasGassification:

biomass+limited amountofoxygen producer gasCombustion: biomass + excess ofoxygen hotcombustion productThe first step in gasification process is pyrolysis in which in the absence of air biomass is subjectedto a temperature of 350 C and the end product char coal,gases(co,co 2,H2,CH 4,H2o) and tar vaporsare produced.In order to better understanding ofpyrolysis, gasification and combustion we have aexample of match stick burning.


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A more quantity picture can also be obtained by technique Thermogravimetricanalysis(TGA).

sThermogravimetricanalysis(TGA) shows the complete analysis of a sample of biomass whensubjected to heated in the absence of air.The TGA is a simple technique in which biomass issuspended in balance pan in furnace and temperature is increased at known rate.

Theoretically(stoichiometric combustion) the ratio of air-to-fuelrequired for thecompletecombustionofthebiomass, is 6:1 to 6.5. As gasification is the process in which the combustion iscarried at sub-stoichiometric conditions and the air-to-fuel ratio is 1.5:1 to 1.8:1.4The gas that is obtained by supply this limited amount of air is known as producer gas or syn gas,

which is combustible and the device which made this process possible is called gassifier .


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This producer gas contain 70% to 90% energy content and some thermal properties of typical biomass and producer gas are shown in table:

Typical properties of producer gas:

Relative position of carbon,hydrogen and oxygen in solid,liquid and gaseous phase chemicalchanges that have been taken place during biomass conversion is shown by phase diagrams

Thermodynamics of Gassification:The adiabatic temperature of biomass is the temperature that would reached if any biomass cometo equilbrium with specific amount of oxygen/air(As it is impossible to achieve equilbrum butsome close state can be achieve in downdraft gassifier).The oxygen used in process is used todetermine the temperature of reaction and product.The oxygen is plotted as equivalence ratio(theused oxygen relative that required for complete oxidation).Very low value of oxygen needed for


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pyrolysis

Equivalence ratio of 0.25 is aproximated for gassificationand Combustion has been taken place forgreater than 1.Adiabatic reaction temperature of biomass reacting with oxygen and air.

As shown in above graph that with oxygen less than 0.25 the char is not converted completely andwith value more than 0.25 the combustion takesplace so the ideal value for equivalence ratiois 0.25

but how we can achieve that value?yes it is possible for static bed,so for fixed bed gassifierequivalence ratio of 0.25 is achievable.The composition of gas produced is shown,Equilibrium gascomposition for reaction of air

The amount of energy remaining in the char and converted from solid to gas is shown


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The low heating value of gas and energy per volume of gas is shown

As we know gasification is the process in which solid carbon whether in the form of coal,coke, orchar, the principle chemical reactions involving carbon,carbon monoxide, carbon dioxide,hydrogen, water (or steam), and methane.The reaction are given belowCombustion reactions,C + 1/2 0 2 = CO - IIIMJ/krnol (1)CO + 1/2 O 2 = C0 2 -283 MJ/kmol (2)H2 + 1/2 O 2 = H 20 242 MJ/kmol (3)Boudouard reaction isC + CO 2 = 2C0 +172 MJ/kmol (4)water gas reaction is

C +H 20 = CO + H 2+l3l MJ/kmol (5)And methanation reaction.C +2 H 2 S CH 4 -75 Mllkmol (6)The reaction 1,2and 3 doesnot need to be considered in equilbrium of syn gas composition.reactions 4, 5, and 6 are enough

CO shift reaction:CO + H 20 7 CO 2 + H 2 4l MJ/kmol (2-7)Calculations are used for the low temperatureC0 shift reaction, which operate at temperatures of

200-250C, Sufficiently accurate results are obtained by this aproximation .Conversion of Sulfur into H 2S and the nitrogen to NH 3 and HCN. The quantities of sulfurandnitrogen in the fuel are so small that they have a negligible effect onthe main Producer gascomponents of hydrogen and carbon monoxide. However it isImportant to consider andacknowledge the fate of sulfur and nitrogen because of their effect on environmentalemissions,catalyst poisons, and so on.in advance (for example, H2SlCOS=9 9.5, NH3=2S%, andt-lt.'N= tU% ot tuel nitrogen,

respectively), and their interaction with carbon, hydrogen,and oxygen is then only constraint tomass and heat balance


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THERMODYNAMIC OF GASIFICATIONDesigners and operators should have some good knowledge about thermodynamicmodeling,

although we all know that in developing models for gasi cation, the requirements of a operator anddesigner are totally different. The designer has been taken the responsibility of calculating a good limited number of designcases and by utilizingStartupand shutdown requirements and process control requirements.

,what will be the results of that feeding.how to defined gas compositions for example, the steammake in a syngascooler.A Expected good model can only be built when both requirements should fulfill.The user need to todo a lot of hardwork,he will go by number of iterative process or calculation to perform his task.Proper calculation for gassification are based on themtodynamics, massand energy balances . In allthese calculations it is important to know the element composition and the temperature of the feedstreams .The gassification is the process in which differentreaction have been taken place some areexothermic and some are endothermic.Thedesired operating temperature is obtained by playing with the exothermicand endothermicreactions.As In gasifiers sometime both oxygen and steam are used to control the temperature, therole ofsteam is not more than that of a moderator.There is also some other methods to equilize the temperature that is to add nitrogen or carbondioxide to the oxygen, or to remove heat indirectly.Following balance equation that are applied in all gassification process

l. Carbon2. Hydrogen3. Oxygen4. Heat5. Sulfur balance.6. Nitrogen balance.7.Ash balance8. Argon Balance


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Chapter 3Gassifier types and their applications

Gasifiers are classified according to the requirement. Each type of gasifier is used for a specific purpose. The processes of oxidation pyrolysis drying and reduction is needed.


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During the biomassgasification procesbiomass is pyrolized cracked or heated by thermal energyand converted into a producer gas. As mentioned earlier this syn gas is purified by different stepandthen. used

Gasifiers

Biomass gasifiers is a unit that heates the biomassinalow-oxygen or produce a gas)The syngas that

is produced from a gasifier is used to drive highly efficient devices for example genserator ets,turbines and fuel cells to generate power.


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Types Of Gasifiers

There or main types of gasifiers:

Fixedbed Fluidizedbed

Fixed bed Gassifier:

The fixed bed gasifier has usuallybed of solid fuel particlesthroughwhichgas moveup or down. Itconsists of annulus tube that contains fuel and it is then oxidized by giving an air inlet port at the

point where we need to have oxidation of the fuel. In the this type of gasifier, biomass moves downthereactor as thegasification happenss. Fixed bed gasifiers are easy to fabricate there is a problem oftar content in the gas. Which can be cleaned.


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Fixed bed gasifiers are generally common. There are two common type of fixed bedgassifier,depending upon the directionofga flow through main chamber

Updraft gassifier:

In updraft gaisifier the direction of draft of air is upward during the gasification process. And thegas is exterated from a port which is at the top. And the controlled airinlet is from below the grate.Flexibility of fuel is an advantage of updraft gasifier and it can alsoaccept cal as fuel and it can bear high content of ash and high moisturelevel.Gasification takes place at the bottom. As the syn gas passes through thefuel bed, it picks tars and moisture content from the fuel . So there are

condensable volatiles from the gas that get out from updraft gassifier.gas comes out at usually 300-500C temperature.

Downdraft Gasifiers

Downdraft gasifiers are desiged for specific fuels to avoid clogging offuel in the reaction chamber. Downdraft wood gasifiers can only operate good on wood like

biomass material and gas is drawn from bottom of the grateand may be above in case of double vessel as in ourcase.reaction takes place in the middle.The gasfrom the downdraf gasifiers canbe cooled and cleaned

tovery high purity by passing it throughfabricfilter orcoolingunit then it can be used inIC engines or fordirectheatingapplicationwhere purity ofgas is a basicrequirement.


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Advantages of downdraft gasifier over updraft :

The updraft gasifierachieves the highestefficiecy as the hotgaspassesthrough fuelbed and leaves itat lowtemperature. The sensible or hidden heat as given by gas is usually used to preheat and dryfuel.One of the major disadvantagesofupdraft gassifier is that in producer gas excessive amount oftar is present and poor loading capability. Hence it is not suitable for running vehicle or could not

be used in ic engine.Fluidized Bed Gasifiers:

In this gasifier the biomass is brought to a bed of char or sand where gasification takes pplace.This system is ver exopensive and delicate and does not accommodate multiple fuels.Prodeucaes high tar and particulate . these are used for larger scales production. Has high flowrates..

Sometimes the fuel is fed from side and sometimes from the above. During optimum gasificationthe fuel is maintained at very high 1300-1800 F. When a fuel particle at this high temperature isintroduced into environment, gasification takes place..It is usually seen that the temperature distribution across the fluidized bed is mostly constantandnormal ranges of temperature is between 700Cand900C.The large thermal or heating capacity of inert or nascent bed material and in addition to the hardmixing related with the fluid bed allow this system to deal with a much greater quantity andmostly having fuel quality is usually a lower.Other Gasifier:Twin fire gas producer:

It is called twin fire gasifier due to combination of co-current and counter-gasfier. Itusually consistsof two reaction zones. Drying of fuel , low-temperature carbonisation, and cracking or breaking at


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. As this is of notmajor importance only if the gas is used for direct heat purpose in which the taris burned directly.But if we have to use the gas for engines, large components will added for gas cleaning .Downdraft fixed bed gasifiers:There will be constraint on . fuel requirements it must beof uniform sized from 4 to 10 cmThe moisture of the biomass not more than of 25 usually.The high temperature of the exit

producer gas is effect efficiency. Of gasification process.

Fluidized bed gasifiers:

This type of gasifier is not suitable to produce syn gas that run engines because of high tar content .Incomplete burning of carbon have effect the energy output. There is a Complex or difficult taskneeded for air to be supplied

Chapter 4Biomass potential

Biomass issuch a fuel that is developed or produced from organic materials, one of the renewableand sustainable source of energy used to produce cheaper electricity or other different forms of

power.The estimated biomass production in the world is seen to be 146 billion tons a year,Some of the basic different types of biomass are:

scrap lumber forest debris certain crops manure


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Wood isone of the largest biomass energy source today which included most of the forestresidues such as:

dead trees branches tree stumps yard clippings wood chips

Industrial biomass is grown from different types of plants i.e Mis canthus Switch glass hemp, corn poplar, willow, sorghum, sugarcane

bamboo

And a lot of tree species, including from eucalyptus to oil palm (palm oil).

As Green wood have up to 50% water by weight. soits properties or characteristics vary mostlywith moisture content.Thechemical composition oftypical biomass is more constant than that of the differentcoals(bituminous, anthracite, lignite) product.However more than 80% of the biomassis usually volatile

but Coal is typically only 20% volatile; which is more dif-ficult to gasify than charcoal.Biomass mostly hasvery low sulfur content and ash content compared to coaletc.However, unlike

coal, biomass comes in a different varietyof physical forms, making it necessary to accommodate

according to the\shapes of the gasifier.So the resulting gasifier design should t be veryfuel-speci c.Analysis technique :There are are two types of analysis:

Proximate analysis Ultimate analysis

Proximate analysis:The proximate analysisindirectly determines the moisture (M),volatile matter [VM], ash (A). and xedcarbon content (C) of a fuel, using standard ASTM tests.Moisture is analyzed by the weightloss is usually observed at110C. . The high heating rates opposewithin an actual gasi erdemanding a higher volatile contentand a lower fixed carbon content than the slow rateasused in the

ASTM measurement, but char get fromthe component is expected to be directly proportional tochar yieldfrom the ASTM testAs shown in table given below that more than 70% of most biomassmaterial isvolatile under the conditions of the test. The proximateanalysisusually includes moisturecontent measuredon a totally wet basis.Ultmate analysis:


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The ultimate analysis is only gives the chemicalcomposition and the HHV of the different fuels.The ultimate analysis generally gives the oxygen, hydrogen, carbon nitrogen, and ash content of

the dry fuel on a different weight percentage basis.Following are the table shows different values of moisture content of biomass by approximateanalysis


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Biomass potiental in Pakistan

In Pakistanthesedays people are thinking to device long term economic policy due to severeeconomic and social problemsThe electricity and gas shortageshavebadly affected the commonman, Industry and commercial activities.The high cost of energy mix is the main reason behind the

power shortage.Pakistan has potential inbiomass. As Pakistan is an agrarian economy with 60% rural work man

ship. As per World Bankstatistics, more than around 26, 280, 000 hectares ofland is under-cultivation in a country like Pakistan.

Agricultural Residues (reference fact and figures from online news report) Wheat strawrice huskrice strawcane trash

bagassecotton sticks

Are some of the important and major crop residues in Pakistan. During 2010-2011, the area undersugarcane cultivation was estimated around 1,029,000 hectares which is more than 4% of the totalcropped area. Cane trash which makes 10% of the sugar cane is totally burned in the fields. Duringthe year 2010-11, around more than 63,920,000 metric tons of sugarcane was grown in this countrywhich in turn give trash generation of around more than 5,752,800 metric tons. It is estimated, thatthe bioenergy potential of cane trash is around 9,475 GWh per year.Cotton is another major and important corp in Pakistan and main and necessary source of rawmaterial to the local textile industry.As it is estimated that cotton is grown on around more than 11% of the total cropped area in thePakistan. The main residue from cotton crop is cotton sticks which left after cotton picking andconstitute approximately 3 times of the cotton that produced.Mostof the cottonsticks are used for domestic fuel in rural areas so only one-fourth of the total can

be considered as important biomass energy resource. The production of cotton sticks during 2010-2011 was estimated 1,474,693 metric tons which is considered equivalent to power generation potential of around more than 3,071 GWh.

The PakistanPunjabprovince has a great potential to produce energy from biomass.it is estimatedthat it can produced up to 5,400MW from thebiomass.Entrepreneur and the Punjabgovernment are hindering and searching foralternative energysourcestoovercome this powershortage in the province,. The provincehaslarge amount of biomassavailable in the shape of rice husk, ginning waste, cotton waste, cotton stalks, wheat straw, cottoncob and wood chips.The Interestinpowergeneration from rice husk was generated when it was heard that a textile mill inour neighbor country is producing 5MW electricity from rice husk.

The study revealed that in our country rice husk has the potential to produce more than 600MW to1,000MW per annum.The APTMAPunjab estimated that cotton wastehas thepotential to produce more than 50-75MW.cotton stalkin the province canproduce 100-200MW of electricity. The sugarcane crop waste alsohas big potential to generate electricity.


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ugar200-


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Chapter 5Design and Fabrication


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criteria for functioning of a good gasi er are: high chalorific value

H2 content accept uptill 20 % moisture in feedstock low content of tar In the gas burn-out of the carbon should be (>95%), which resulted a high e iciency

The main parameters for design are: diameter of the constriction the throat


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diameter of the tube height of the reduction zone. place or height of air inlet(s). surface area of air inlet air inlet angle

the velocity of air is different in different processes of the gasifier the residence time iof the gas istghat which tells us that how much time the gas stays in a specific zone. And the esidence timedetermines the .All know that real residence time is very dif cult. Also the volume-, ows of gas ,solid that is changed through the gasi er and height of a zone is controlled by numerous ,interdependent or correlated factors. They are totally dependent of heat generated and are used inthe different stages. The necessary factor that determining the correct circumstances of the whole the process is mostlytaken from the cross-section of the apparatus..

As it is usually considered that in the burning or oxidation zone all the gas that present should be burned completely and which is count to be a very fast reaction.

Besides of the total residence time, as it is calculated for the total or complete volume of a zone,the part of each zone should be such that where the most of the reaction takes placeThe actual zone where burning have been taken place is mostly thin.

The last step is pyrolysis and the reduction will start very fastly near to oxidation zone. beyondsome temperature cracking will start, and importantly charcoal is usually considered to catalyzeit. So this zone should be kept as large in dimension as possible.It is usually considered that the charcoal level ismostly formed at the 500C level.The Cracking isassumed to occur above 950C.It is noted that complete cracking the tar is only seen to be possible when the charcoal zone is highenough.The height of the pyrolysis zone that is the cause of heat transport, by conduction,convectionand radiation.As the actual burning zone isusually small and the reduction zone is starts at the height of the

lowest, airinlet.The length of the zone in which the reduction process actually seems to be takes place isdetermined by theprogress of the endothermic reaction..Heat losseshappened mostly and the reaction could be stops before completion and remwdy of thisis a good insulation that isneeded. Before heating air is usually unprofitable Ahuge bed isalso notacceptable ,it is only because of toohigh presure drop that occur, but also some heat losses.The burning zonepositioned is usually directly at the post of the air inlet.The realburning of thegasses is taking place only on that area which is very close to the actual inlets.The hot zone isalready extendedthrough complete penetration of the hot gasses, directed by the

power of the enteringair.The extensionof the hot zone is one the good step, its meansthat the complete area at the airinletheight that The burnt gasses aretaken up usually in a circulationcaused by the stream ofair.Sobythis they enter againrcirculation the part which hot one very nearthe inlets.Diametershould,ntlarge and the wallshoulbeinclined. It is noted that. Thenecessary measures are usually be the height of the air inlet above the the throat at athroatinclination of 45 .After studying above design constraints and rules and by following some of below tables we startedfabricating our project.


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1.1. Fire tube dimensions

Inside diameter (inches) Minimum length (inches) Engine power (hp) Typical engine displacement (cubic inches)2- 16 5 104- 16 15 306 16 30 607 18 40 808 20 50 1009 22 65 13010 24 80 16011 26 100 20012 28 120 24013 30 140 28014 32 160 320

Our gasifier Design and dimension


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Tabel taken from FEMA


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Height of gassifier 60Outer cylinder diameter 18Inner diameter 8Air inlet nozzle diameter 0.75

Air inlet height 8Air inlet angle 60Constriction diameter 6Constriction height 11

Units: Inches


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A cyclonecentrifugala spread she

eparator isorce compoet which is

essentiallynent. The eased on th

a gravitatiquation bel following

nal separaw are usedquation

or thathasto design c

beenusuallyclone filter

enhancedand there i

35

by aalso


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Chapter 6Analysis

We used Solid works flow simulation Analysis to find the velocities of thesyn gas at different points in the gasifier.Boundary conditions.


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Velocity contour plot:


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Streamlines Plot:

Pressure Ccontour plot:


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(Solid works Flow-Express report)

INPUT DATA

Initial Mesh SettingsAutomatic initial mesh: OnResult resolution level: 3Advanced narrow channel refinement: OffRefinement in solid region: Off

Geometry ResolutionEvaluation of minimum gap size: AutomaticEvaluation of minimum wall thickness: Automatic

Computational Domain

SizeX min -0.311 mX max 0.311 mY min -0.323 mY max 1.138 mZ min -0.229 m


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Z max 0.304 m

Physical FeaturesHeat conduction in solids: OffTime dependent: OffGravitational effects: OnFlow type: Laminar and turbulentHigh Mach number flow: OffHumidity: OffDefault roughness: 0 micrometer

Gravitational SettingsX component 0 m/s^2Y component -9.81 m/s^2Z component 0 m/s^2

Default wall conditions: Adiabatic wall

Initial Conditions

Thermodynamic parameters Static Pressure: 101325.00 PaTemperature: 293.20 K

Velocity parameters Velocity vectorVelocity in X direction: 0 m/sVelocity in Y direction: 0 m/sVelocity in Z direction: 0 m/s

Concentrations Substance fraction by mass

Carbon dioxide 0.3333

Hydrogen 0.3333

Methane 0.3333Turbulence parameters Turbulence intensity and length

Intensity: 2.00 %Length: 0.006 m

Material Settings

FluidsCarbon dioxide Hydrogen Methane

Boundary ConditionsOutlet Volume Flow 1Type Outlet Volume FlowFaces Face@Boss-Extrude14Coordinate system Face Coordinate SystemReference axis XFlow parameters Flow vectors direction: Normal to face


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Volume flow rate normal to face: 0.0094 m^3/s

Inlet Volume Flow 1Type Inlet Volume FlowFaces Face@Boss-Extrude15Coordinate system Face Coordinate SystemReference axis XFlow parameters Flow vectors direction: Normal to face

Volume flow rate normal to face: 0.0037 m^3/sFully developed flow: NoInlet profile: 0

Thermodynamic parameters Approximate pressure: 101325.00 PaTemperature: 293.20 K



Hydrogen 0.3333

Methane

0.3333Turbulence parameters Turbulence intensity and lengthIntensity: 2.00 %Length: 0.006 m

Boundary layer parameters Boundary layer type: Turbulent

Environment Pressure 1Type Environment PressureFaces Face@Boss-Extrude12Coordinate system Face Coordinate SystemReference axis XThermodynamic parameters Environment pressure: 101325.00 Pa

Temperature: 293.20 KConcentrations Substance fraction by mass


Hydrogen 0.3333

Methane 0.3333

Turbulence parameters Turbulence intensity and lengthIntensity: 2.00 %Length: 0.006 m



Temperature: 293.20 KConcentrations Substance fraction by mass


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Hydrogen 0.3333

Methane 0.3333



Calculation Control Options

Finish ConditionsFinish conditions If one is satisfiedMaximum travels 4Goals convergence Analysis interval: 5e-001

Solver RefinementRefinement: Disabled

Results SavingSave before refinement On

Advanced Control OptionsFlow FreezingFlow freezing strategy Disabled

RESULTS

Calculation Mesh

Basic Mesh Dimensions Number of cells in X 10 Number of cells in Y 24 Number of cells in Z 8

Number Of CellsTotal cells 54672

Fluid cells 22464Solid cells 9829Partial cells 22379Irregular cells 0Trimmed cells 0

Maximum refinement level: 4


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Goals Name Unit Value Progress Use in

convergenceDelta Criteria

Min/Max Table Name Minimum Maximum

Pressure [Pa] 101302.53 101312.47Temperature [K] 293.20 293.21Velocity [m/s] 0 11.970Vorticity [1/s] 8.995e-004 1163.979

Engineering Database

Gases

Carbon dioxidePath: Gases Pre-DefinedSpecific heat ratio (Cp/Cv): 1.287Molecular mass: 0.0440 kg/molDynamic viscosity

0

0.00001

0.00002

0.00003

0.00004

0.00005

0.00006

0.00007

0.00008

0.00009

0 500 1000 1500 2000 2500 3000 3500

D y n a m i c v i s c o s i t y [ P a * s ]

Temperature[K]


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Specific heat (Cp)

Thermal conductivity

HydrogenPath: Gases Pre-DefinedSpecific heat ratio (Cp/Cv): 1.404Molecular mass: 0.0020 kg/mol

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 500 1000 1500 2000 2500 3000 3500

S p e c i f i c h e a t ( C p ) [ J / ( k g * K ) ]

Temperature[K]

0

0.2

0.4

0.6

0.8

1

1.2

0 500 1000 1500 2000 2500 3000 3500

T h e r m a l c o n d u c t i v i t y [ W / ( m * K ) ]

Temperature[K]


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Dynamic viscosity

Specific heat (Cp)


MethanePath: Gases Pre-Defined

0

0.000005

0.00001

0.000015

0.00002

0.000025

0.00003

0.000035

0.00004

0.000045

0 500 1000 1500 2000 2500 3000 3500


Temperature[K]

0

10000

20000

30000

40000

50000

60000

70000

80000

0 500 1000 1500 2000 2500 3000 3500


Temperature[K]

0

0.5

1

1.5

2

2.5

3

3.5

4

0 500 1000 1500 2000 2500 3000 3500


Temperature[K]


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Specific heat ratio (Cp/Cv): 1.305Molecular mass: 0.0160 kg/molDynamic viscosity

Specific heat (Cp)


0

0.000005

0.00001

0.000015

0.00002

0.000025

0.00003

0.000035

0 200 400 600 800 1000 1200 1400


Temperature[K]

0

1000

2000

3000

4000

5000

6000

0 200 400 600 800 1000 1200 1400


Temperature[K]

0

0.05

0.1

0.15

0.2

0.25

0.3

0 200 400 600 800 1000 1200 1400 1600


Temperature[K]


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Cyclone Filter:


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Boundary conditions.

During calculation:


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Flow trajectories and velocity trend:


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Velocity Cut plot Contours :


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Flow trajectories and pressure trend.

Pressure cut plot.

Particulate study


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(Solid works Flow-Express report)

INPUT DATA

Initial Mesh SettingsAutomatic initial mesh: OnResult resolution level: 3Advanced narrow channel refinement: OffRefinement in solid region: Off

Geometry ResolutionEvaluation of minimum gap size: AutomaticEvaluation of minimum wall thickness: Automatic

Computational Domain

SizeX min -0.076 mX max 0.173 mY min -0.302 mY max 0.279 mZ min -0.076 m

Z max 0.076 m

Physical FeaturesHeat conduction in solids: OffTime dependent: OffGravitational effects: On


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Flow type: Laminar and turbulentHigh Mach number flow: OffHumidity: OffDefault roughness: 0 micrometer

Gravitational SettingsX component 0 m/s^2Y component -9.81 m/s^2

Z component 0 m/s^2

Default wall conditions: Adiabatic wall

Initial ConditionsThermodynamic parameters Static Pressure: 101325.00 Pa

Temperature: 293.20 KVelocity parameters Velocity vector

Velocity in X direction: 0 m/sVelocity in Y direction: 0 m/sVelocity in Z direction: 0 m/s



Methane 0.3333

Hydrogen 0.3333


Material Settings

FluidsCarbon dioxide Methane Hydrogen

Boundary ConditionsOutlet Volume Flow 1Type Outlet Volume FlowFaces Face@Boss-Extrude7Coordinate system Face Coordinate SystemReference axis XFlow parameters Flow vectors direction: Normal to face

Volume flow rate normal to face: 0.0094 m^3/s


Temperature: 293.20 K


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Methane 0.3333

Hydrogen 0.3333



Calculation Control Options

Finish ConditionsFinish conditions If one is satisfiedMaximum travels 4Goals convergence Analysis interval: 5e-001

Solver RefinementRefinement: Disabled

Results SavingSave before refinement On

Advanced Control OptionsFlow FreezingFlow freezing strategy Disabled

RESULTS

Calculation Mesh

Basic Mesh Dimensions Number of cells in X 10 Number of cells in Y 22 Number of cells in Z 6

Number Of CellsTotal cells 13745

Fluid cells 5260Solid cells 3650Partial cells 4835Irregular cells 0Trimmed cells 0

Maximum refinement level: 2


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Goals Name Unit Value Progress Use in

convergenceDelta Criteria

Min/Max Table Name Minimum Maximum

Pressure [Pa] 101310.58 101322.49Temperature [K] 293.20 293.20Density [kg/m^3] 0.21 0.21Velocity [m/s] 0 7.856Velocity (X) [m/s] -6.274 5.065Velocity (Y) [m/s] -2.601 7.496Velocity (Z) [m/s] -5.213 4.782Temperature (Fluid) [K] 293.20 293.20Mach Number [ ] 0 9.71e-003Vorticity [1/s] 0.005 675.898Shear Stress [Pa] 0 0.15Relative Pressure [Pa] -14.42 -2.51Heat Transfer Coefficient[W/m^2/K]

0 0

Surface Heat Flux [W/m^2] 0 0

Crop residues productions in Pakistan ( Agri. Stat.2011)


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Chapter 7


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Testing and Results

Engine exhaust results while running on syn gas. Combustion efficiency 85%

Temp pre heat 47 c

Temp stack 141 c

Oxygen 3.1%

Carbon mono-oxide 751 PPM

Carbon di-oxi 9%

Excess air 15%

Nitrogen oxide 346 PPM

Nitrous oxide 363 PPM

Sulpher di-oxide 0 PPM

During testing:

Testing was done at College Of E&ME, NUST The emissions ofthe generator engine running on syn gas was analysed and Theresults were satisfactory and we clearly got the data validated thatEngine running on syn gas has less emissions as compared to

petrol as a fuel.


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Applications: Tractors, harvesters, irrigation systems. Grain drying, green house heating. Generation of mechanical and electrical power. Diesel as well as petrol engines

Conclusions:

Biomass gasification an attractive energy system for Agricultural

purposes. Fuels for gasification: charcoal,wood and biomass residues. Producer gas uses in I-C engines and grain drying. A spark ignition engine running on producer gas on average produces

0.55-0.75 kwh of energy from 1 kg of biomass.


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Compression ignition engines can not run completely on producer gas.Thus to produce 1 kwh of energy they consume 1 kg of biomass and 0.07liters of diesel. Consequently they effect 80-85% diesel saving

In future, producer gas in fuel cell and small scale irrigation systems fordeveloping countries offer the greatest potentialities.


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References 1. Solar Energy Research Institute (SERI), Generator Gas The Swedish

Experience from 1939-1945, SERI, Golden, Colorado, 1979.2. Reed, T. B., Graboski, M., and Markson, M., The SERI High Pressure

Oxygen Gasifier, Report SERI/TP-234-1455R, Solar Energy ResearchInstitute, Golden, Colorado, Feb. 1982.

3. H. LaFontaine, Biomass Energy Foundation, INC. Miami, Florida.Federal Emergency Management Agency (FEMA) Construction of aSimplified Wood Gas for Fueling Internal Combustion Engines in aPetrolium Emergency 1989.

4. Wood gas as engine fuel, Food and Agriculture Organization of theUnited Nations (FAO) 1986.

pr-sof-1262-design and fabrication of wood gasification plant that runs a 15 kva static load...

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