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BIOMASS GASIFICATION BIOMASS GASIFICATION TECHNIQUE FOR ELECTRICAL TECHNIQUE FOR ELECTRICAL

POWER GENERATIONPOWER GENERATION

INTRODUCTIONINTRODUCTION One seventh of the total energy is from One seventh of the total energy is from

biomassbiomass 1.5 billion of the world population has 1.5 billion of the world population has

biomass as main energy resourcebiomass as main energy resource Biomass can be transferred to useful Biomass can be transferred to useful

thermal, electrical energy and fuel as thermal, electrical energy and fuel as power by means of different techniquespower by means of different techniques

Problem/ opportunity, Goal, Problem/ opportunity, Goal, adjectives to achieve the goaladjectives to achieve the goal

.Problem/ Opportunity.Problem/ Opportunity- Villages in north of Iraq are using kerosene based lighting system, Villages in north of Iraq are using kerosene based lighting system,

diesel driven water pumps for irrigation and drinking waterdiesel driven water pumps for irrigation and drinking water.Goal of the project.Goal of the project-Using biomass gasification technique to generate electricity for lighting, -Using biomass gasification technique to generate electricity for lighting,

irrigation and drinking water.irrigation and drinking water.. Adjectives to achieve the goal. Adjectives to achieve the goal-Enough areas to be allocated for planting forest necessary to produce -Enough areas to be allocated for planting forest necessary to produce

feedstocks for the plantfeedstocks for the plant- Enough resources to be assigned to build the plant within reasonable Enough resources to be assigned to build the plant within reasonable

limited timelimited time- Federal government of Kurdistan builds the plant on non profit baseFederal government of Kurdistan builds the plant on non profit base

The model adopted in this projectThe model adopted in this project

A Village of 50 households are taken as a A Village of 50 households are taken as a modelmodel

-Main source of their income depends on -Main source of their income depends on cultivation of different seasonal cropscultivation of different seasonal crops

Each household is of 7 persons as averageEach household is of 7 persons as average Main their needs is electricity for lighting , Main their needs is electricity for lighting ,

irrigation and drinking waterirrigation and drinking water

Calculation of lighting loadCalculation of lighting load

Each household assumed to have 2 living rooms Each household assumed to have 2 living rooms 4.5x4m and a kitchen of 3x4 m4.5x4m and a kitchen of 3x4 m

1 lamp to be installed for each room and one lamp 1 lamp to be installed for each room and one lamp for external lighting. The total is 4 lamp for external lighting. The total is 4 lamp

Mark 4 lamps are usedMark 4 lamps are used All lamps working 4 hrs daily.All lamps working 4 hrs daily. There is a centralized power generation systemThere is a centralized power generation system Each house hold is supplied with one 12V SLA Each house hold is supplied with one 12V SLA

batteries to drive lighting system with power batteries to drive lighting system with power transfer efficiency of 0.85transfer efficiency of 0.85

Calculation of lighting load continueCalculation of lighting load continue

Total power consumed by each household= Total power consumed by each household= 1.2 1.2 ???? *4 = 4.8 watt *4 = 4.8 watt

Total power consumed by the village= 50X Total power consumed by the village= 50X 4.8 = 240 watt4.8 = 240 watt

Assume lighting load for other facilities such Assume lighting load for other facilities such as schools, health care, police centre = 240 as schools, health care, police centre = 240 watt.watt.

Assume 5% Assume 5% ???? losses then the total lighting losses then the total lighting load of the village = 420 w load of the village = 420 w ????????

Other loadsOther loads

Assume rating of induction motor for irrigation and Assume rating of induction motor for irrigation and drink water pump to be drink water pump to be

20 hp = 14.92 kw20 hp = 14.92 kw Assume milling machine motor( for milling the Assume milling machine motor( for milling the

crops) rating is 10 hp = 7.46 kwcrops) rating is 10 hp = 7.46 kw Total load = 0.42 + 14.92 + 7.46 = 22.8 kwTotal load = 0.42 + 14.92 + 7.46 = 22.8 kw Assume 10% future load increasing Assume 10% future load increasing Hence the total load will be 22 kw Hence the total load will be 22 kw ???? which is the which is the

capacity of the gasifier system capacity of the gasifier system

Energy stored Energy stored requirements( Battery)requirements( Battery)

Total current consumed by each household for Total current consumed by each household for lightinglighting

= (1.2W/12V) X 4 = 0.4 A= (1.2W/12V) X 4 = 0.4 A Take the capacity of the battery as 10 times the Take the capacity of the battery as 10 times the

load Ah, then C = 10(0.4A x 1h) = 4 Ahload Ah, then C = 10(0.4A x 1h) = 4 Ah We select SLA battery of 7AhWe select SLA battery of 7Ah Energy in this battery is 13.2V x 7Ah = 92.4 WhEnergy in this battery is 13.2V x 7Ah = 92.4 Wh

Charging station requirementsCharging station requirements

E (discharging)= 4 x [4h x1.2W/0.85] = 22.5 WhE (discharging)= 4 x [4h x1.2W/0.85] = 22.5 Wh E (recharging)= 22.5/0.85 = 26.4 WhE (recharging)= 22.5/0.85 = 26.4 Wh If the batteries are taken to the charging station If the batteries are taken to the charging station

every other day, i.e. half the batteries every dayevery other day, i.e. half the batteries every day Hence the total recharging energy of the Hence the total recharging energy of the

charging station= 26.4 x 25 = 661.8 Whcharging station= 26.4 x 25 = 661.8 Wh

Calculation of the required biomass Calculation of the required biomass for this projectfor this project

Generated energy per year = 20 Generated energy per year = 20 ???? x 6 x 6 ???? x 365 = 43800Kwh x 365 = 43800Kwh Biomass required to generate one Kwh = 1 Kg on averageBiomass required to generate one Kwh = 1 Kg on average Hence the total mass of required biomass is 43800 Kg , say Hence the total mass of required biomass is 43800 Kg , say

45 ton45 ton If we consider a well managed plantation, each hectare will If we consider a well managed plantation, each hectare will

produce 15 tons biomass / year, so we need about 3 hectareproduce 15 tons biomass / year, so we need about 3 hectare Taking factor of sharing the land with agricultural crops , then Taking factor of sharing the land with agricultural crops , then

the total hectare needed will be 3 X 5 = 11 the total hectare needed will be 3 X 5 = 11

Biopower technologiesBiopower technologies

Direct firingDirect firing Co-firingCo-firing GasificationGasification PyrolysisPyrolysis Anaerobic digestionAnaerobic digestion Most biopower plants use direct firingMost biopower plants use direct firing Gasification uses high temperatures and an Gasification uses high temperatures and an

oxygen- starved environment to convert biomass oxygen- starved environment to convert biomass into synthesisinto synthesis

Gasification fuels and selection of Gasification fuels and selection of right gasifier for each fuelright gasifier for each fuel

Gasification fuels include: charcoal, wood and waste Gasification fuels include: charcoal, wood and waste woods as well as agricultural residueswoods as well as agricultural residues

Most important fuel propertiesMost important fuel properties- Energy contentEnergy content- Moisture matterMoisture matter- Ash content and ash chemical compositionAsh content and ash chemical composition- ReactivityReactivity- Charring densityCharring density- N.B Before choosing a gasifier, it is important to ensure N.B Before choosing a gasifier, it is important to ensure

that the fuel meets the requirements of the gasifierthat the fuel meets the requirements of the gasifier- The downdraught gasifier is our choiceThe downdraught gasifier is our choice

Types of biomass gasification Types of biomass gasification processprocess

Large scale application (500 Kw and above)Large scale application (500 Kw and above) Medium scale application(30 - 300 Kw)Medium scale application(30 - 300 Kw) Small scale applications(7 - 30Kw)Small scale applications(7 - 30Kw) Micro scale application(1 - 30Kw)Micro scale application(1 - 30Kw)

Types of GasifiersTypes of Gasifiers

Updraught or counter current gasifierUpdraught or counter current gasifier

Cont. Types of GasifiersCont. Types of Gasifiers

Downdraught gasifierDowndraught gasifier

Cont- Types of GasifiersCont- Types of Gasifiers

Cross- draught gasifierCross- draught gasifier Fluidized bed gasifierFluidized bed gasifier Other types of gasifiersOther types of gasifiers

Processes occurring in down- Processes occurring in down- draught gasifierdraught gasifier

Process in drying zoneProcess in drying zone Process in pyrolysis zoneProcess in pyrolysis zone process in oxidation zoneprocess in oxidation zone Process in reduction zoneProcess in reduction zone

Cleaning dust from the gasCleaning dust from the gas Gas coolingGas cooling

Economical analysisEconomical analysis The expected generator life assumed to 20 yearsThe expected generator life assumed to 20 years Discounting rate 10%Discounting rate 10% Diesel engine parts replacement after 8 years cost to 10% and 20% after 16 yearsDiesel engine parts replacement after 8 years cost to 10% and 20% after 16 years Gasifier and other auxiliary systems life time is 10 yearsGasifier and other auxiliary systems life time is 10 years Inflation rate is considered 0%Inflation rate is considered 0% The SLA batteries to be replaced each 4 yearsThe SLA batteries to be replaced each 4 years Generator lead acid battery to be replaced each 4 yearsGenerator lead acid battery to be replaced each 4 years The feedstock cost is considered $30/ monthThe feedstock cost is considered $30/ month Total cost is $ 5311.75Total cost is $ 5311.75 Total Kwh = 876000 during 20 years Total Kwh = 876000 during 20 years Cost of each kwh= $0.05Cost of each kwh= $0.05 If using kerosene for lighting, each household pay $ 180 / yearIf using kerosene for lighting, each household pay $ 180 / year If using solid state lighting , each household pay If using solid state lighting , each household pay = 19.2 = 19.2 ???? x 365 x 0.0619 x 365 x 0.0619 ???? = $0.433 = $0.433 Percentage is 0.24% , is not amazing!Percentage is 0.24% , is not amazing!

Biomass environmental impactsBiomass environmental impacts

Reducing greenhouse gas emissionReducing greenhouse gas emission Energy crops restore and reestablish the forest coverEnergy crops restore and reestablish the forest cover The ash by- products will be used as a fertilizer thus The ash by- products will be used as a fertilizer thus

reducing the dependence on nitrogen fertilizersreducing the dependence on nitrogen fertilizers Enriches the soil and organic matter to avoid the soil Enriches the soil and organic matter to avoid the soil

erosionerosion

Negative impacts:Negative impacts: The emission of CO and other dangerous gases has The emission of CO and other dangerous gases has

negative impact on the environment, so this needs negative impact on the environment, so this needs appropriate managing planappropriate managing plan

Without proper plan of planting and harvesting, the de- Without proper plan of planting and harvesting, the de- frosting frosting ???? of the lands will result of the lands will result

Project social impactsProject social impacts

Jobs will be createdJobs will be created Local people will be encouraged to plant new Local people will be encouraged to plant new

types of feedstocks and they will get extra income.types of feedstocks and they will get extra income. The area will be lighted up and new business will The area will be lighted up and new business will

be createdbe created Education level , health care and security will be Education level , health care and security will be

improved.improved. The dependence on conventional and fossil The dependence on conventional and fossil

energy will be reduced so that the cost of the energy will be reduced so that the cost of the energy as a whole will be reducedenergy as a whole will be reduced

General recommendationsGeneral recommendations

Fast growing trees should be managedFast growing trees should be managed The older branches to be harvested in cycle The older branches to be harvested in cycle

of 2-6 month cycleof 2-6 month cycle The main stem is kept intact and hence the The main stem is kept intact and hence the

forest coversforest covers

Questions?Questions?