Biomass/ Geothermal Energy [AB ENERGY]

c. Geothermal

Heat energy derived from earth crust.

a. Biomass

b. Ocean thermal

c. Geothermal

d. All of the above

c. All of the above

Applications of geothermal energy.

a. Electricity Generation

b. Heating

c. All of the above

d. Noe of the above

d. All of the above

Sources of geothermal heat.

a. Hot water

b. Steam

c. Hot dry rock

d. All of the above

a. Geothermal power plant

A geothermal system that generate electricity using

steam or hot water from the Earth.

a. Geothermal power plant

b. Direct-Use System

c. Geothermal Heat Pump

d. None of the above

b. Direct-Use System

A geothermal system that utilize the heat for various

applications like heating buildings or greenhouses.

a. Geothermal power plant

b. Direct-Use System

c. Geothermal Heat Pump

d. None of the above

c. Geothermal Heat Pump

A geothermal system that is characterized with a

relatively stable temperature which can be found in

shallow subsurface for heating and cooling.

a. Geothermal power plant

b. Direct-Use System

c. Geothermal Heat Pump

d. None of the above

10% to 23%.

thermal efficiency of a geothermal

power plant

Dry Steam & Flash Plants

Binary Cycle Plants

Classifications of Geothermal Powerplant

Dry Steam & Flash Plants

[Classification of Geothermal Powerplant]

These extract

high-temperature steam directly from the

earth.

15%

and 23%.

Dry Steam & Flash Plants thermal efficiency

Binary Cycle Plants

[Classification of Geothermal Powerplant]

These use lowertemperature

reservoirs (often below

150°C) and pass the geothermal heat

through a secondary working fluid.

7% to 12%.

Binary Cycle Plants thermal efficiency

a. Dry steam plants

These plants use naturally occurring steam from the Earth

to directly drive turbines and generate electricity.

a. Dry steam plants

b. Flash steam plants

c. Binary cycle plants

d. None of the above

b. Flash steam plants

These plants uses high-pressure, hot water from

geothermal reservoirs and is quickly pass into steam as it is

brought to the surface, which then powers turbines.

a. Dry steam plants

b. Flash steam plants

c. Binary cycle plants

d. None of the above

c. Binary cycle plants

These plants use a secondary fluid with a lower boiling

point than water to capture heat from lower-temperature

geothermal resources, which then vaporizes and drives

turbines.

a. Dry steam plants

b. Flash steam plants

c. Binary cycle plants

d. None of the above

a. Enhanced Geothermal System

These systems involve creating or enhancing

geothermal reservoirs by fracturing hot, dry rock

formations and injecting water to create steam or hot

water.

a. Enhanced Geothermal System

b. Direct Geothermal System

c. Hydrothermal System

d. None of the above

c. returned

To maintain pressure and sustain the heat source n

geothermal power plant, cooled water or condensed

steam is typically ____ to the geothermal reservoir.

a. diverted out

b. flash out

c. returned

d. None of the above

b. a turbine

To generate electricity in geothermal power plant,

the steam or hot vapor basically spins ____ that is

coupled to a generator.

a. an impeller

b. a turbine

c. a rotor

d. None of the above

h. All of the Above

Key components of geothermal power plant.

a. Production and Injection wells

b. Pipelines and Piping Systems

c. Powerhouse

d. Cooling Tower

e. Pumping System

f. Gas Removal System

g. Hydrogen Sulfide Abatement System

h. All of the Above

i. Four of the above

a. Production well

These wells are drilled deep into the Earth's crust

to reach geothermal reservoirs, tapping into hot

water or steam.

a. Production well

b. Injection well

c. Pump well

d. All of the above

b. Injection Well

Well used to return geothermal fluid back into the

reservoir of the power plant.

a. Production Well

b. Injection Well

c. Pump Well

d. All of the above

a. Pipe lines

Used to transport geothermal fluid (steam or hot water)

from the production wells to the power plant and back to

the injection wells.

a. Pipe lines

b. Piping systems

c. Pump system

d. All of the above

b. Piping systems

Include various pipelines for different purposes, such as

carrying steam to the turbine, returning cooled water to the

injection well, and transporting fluids for heat exchange

processes

a. Pipe lines

b. Piping systems

c. Pump system

d. All of the above

a. Heat Exchanger/Steam Separator

These direct steam from the hot water and transfer

the heat to a secondary fluid, which powers the turbine.

a. Heat Exchanger/Steam Separator

b. Pipe lines

c. Pumps

d. All of the above

a. Turbine/Generator

The steam (or heated secondary fluid) is used to

spins the ___ converting thermal energy into mechanical

and electrical energy .

a. Turbine/Generator

b. Turbine

c. Generator

d. All of the above

a. Condenser

Cools the steam or secondary fluid after it has passed

through the turbine, converting it back into a liquid.

a. Condenser

b. Heat exchanger

c. Cooling tower

d. All of the above

b. Cooling Tower

These structures help dissipate heat from the

condenser, cooling the working fluid and enabling its

reuse.

a. Condenser

b. Cooling Tower

c. Heat exchanger

d. All of the above

a. Gas Removal System

These systems remove gases before they are released

into the atmosphere.

a. Gas Removal System

b. Gas Cleaning System

c. Gas Purifying System

d. None of the above

b. Hydrogen sulfide

Used to remove ___ to prevent environmental issues

and corrosion.

a. Carbon dioxide

b. Hydrogen sulfide

c. Oxygenated hydrogen

d. None of the above

Biomass

refers to all organic materials that originate from living organisms such as wood,

agricultural residues, animal wastes and others

Thermochemical conversion

Biochemical conversion

Biomass conversion processes (2)

gasification,

pyrolysis and carbonization,

combustion

Thermochemical conversions (4)

ethanol production

biogas production

Biochemical conversion (2)

Heat Application

Biomass

fuel is converted into a

combustible gas and is

consequently used as source of

heat for cooking, drying, kiln firing,

etc.

Mechanical Power

Generation for Steady Load

Biomass fuel is converted into

combustible gas and then cleaned

before it is used as fuel for internal

combustion engines, instead of

using crude oil. The engine is

then used for powering stationary

pumps, rice mills, corn mills, and

others, or for rural community

application by coupling it to a

generator to produce electricity for

home and street lightings and for

energizing schools, restaurants,

apartments, and others.

d. None of the above

Which of the following is not a biomass?

a. Corn cobs

b. Rice husks

c. Peat

d. None of the above

a. Producer gas

Product resulting from subjecting biomass to thermochemical

reaction.

a. Producer gas

b. Biodiesel

c. Bioethanol

d. Biogas

e. None of the above

b. Pyrolysis

If high percentage of carbon is required from biomass,

which of the following thermo-chemical process would you

recommend?

a. Direct combustion

b. Pyrolysis

c. Gasification

d. All of the above

a. 1200 kcal/m3

Heating value of producer gas is typically at ____.

a. 1200 kcal/m3

b. 2,245 kcal/m3

c. 3,000 kcal/m3

d. None of the above

d. All of the above

Type of engine that can be fueled with producer gas.

a. Gas engine

b. Diesel engine

c. Gasoline engine

d. All of the above

b. diesel

Biomass-gas engine is basically a modified ____

engine.

a. gasoline

b. diesel

c. steam

d. None of the above

b. 50-70 %

Percentage amount of diesel fuel that can be

replaced with gas producer.

a. 20-40 %

b. 50-70 %

c. 90-100 %

d. None of the above

a. 10-20 %

At an arbitrary speed, the power output of a

diesel engine is reduced by ____ when it is

powered with gas producer.

a. 10-20 %

b. 30-50 %

c. 50-70 %

d. None of the above

b. CO, H2, and CH4

Gases produced from producer gas.

a. CO2 and CH4

b. CO, H2, and CH4

c. CO2

d. All of the above

e. None of the above

a. Below 30% of stoichiometric air

Amount of air needed in pyrolysis biomass.

a. Below 30% of stoichiometric air

b. 30 to 40 % of stoichiometric air

c. Above 40% of the stoichiometric air

d. None of the above

a. Up to - 0.2

Equivalence ratio for pyrolyzers.

a. Up to - 0.2

b. 0.2 - 0.4

c. 0.4 and above

d. None of the above

b. 0.2 - 0.4

Equivalence ratio for biomass gasifiers.

a. 0 - 0.2

b. 0.2 - 0.4

c. 0.4 and above

d. None of the above

a. 56 kg of air per hr

What is the required airflow to gasify rice husk in a

gasifier that consumes 40 kg per hour of fuel? The

stoichiometric air requirement of rice husks is 4.7

kgair/kgfuel. Consider an equivalence ratio of 0.3.

a. 56 kg of air per hr

b. 70 kg of air per hr

c. 86 kg of air per hour

d. None of the above

a. high superficial velocity

Channel formation at the fuel bed inside the

gasifier reactor basically is the result of ____.

a. high superficial velocity

b. overloading of fuel during operation

c. reactor operating at a low temperature

d. None of the above

c. 20-23 cm/sec

To minimize channel formation inside the gasifier

reactor, the superficial gas velocity in the char bed

should not exceed ____.

a. 8-9 cm/sec

b. 15-20 cm/sec

c. 20-23 cm/sec

d. None of the above

c. Gasification

Conversion process of solid biomass to

combustible gaseous fuel through thermochemical

reaction.

a. Digestion

b. Carbonization

c. Gasification

d. None of the above

c. Carbon monoxide

Primary gas produced during gasification.

a. Methane

b. Carbon dioxide

c. Carbon monoxide

d. All of the above

b. 30 to 40 % of stoichiometric air

Amount of air needed in gasifying biomass.

a. Below 30% of stoichiometric air

b. 30 to 40 % of stoichiometric air

c. Above 40% of the stoichiometric air

d. None of the above

c. 34.2 m³/hr

A corn cob has an stoichiometric air requirement of

5.7 kg air/kg fuel. If 30 kg of corn cobs is required to

be burned per hour, how much air in m³/hr is required

for the system. Consider an equivalence ratio of 0.25

a. 30.68 m³/hr

b. 31.28 m³/hr

c. 34.2 m³/hr

d. None of the above

b. 110-210 kg/m2-hr

Gasification rate of rice hull ranges from ____.

a. 90-105 kg/m2-hr

b. 110-210 kg/m2-hr

c. 125-140 kg/m2-hr

d. None of the above

c. 0.39 m

A rice husk gasifier is operating at 20kg-per-hour

fuel rate. What is the diameter required for the

gasifier if the designed specific gasification rate is

160 kg/hr-m2?

a. 0.20 m

b. 0.25 m

c. 0.39 m

d. None of the above

b. Moving-bed

Type of gasifiers suitable for rice husk gasifier

operating on a continuous mode.

a. Fixed bed

b. Moving-bed

c. Fluidized bed

d. None of the above

d. All of the above

Engine suitable for fueling biomass producer gas.

a. Gasoline engine

b. Diesel engine

c. Gas engine

d. All of the above

kilowatt thermal

kWt

kilowatt mechanical

kWm

kilowatt electrical

kWe

Gasification

the process of converting solid carbon into

combustible carbon monoxide by thermo-chemical reaction of fuel.

air; carbon

In complete combustion, the process takes place with excess ___ while in gasification, the process takes place with excess ___

biomass

The process of gasification converts ____ into carbon- and

hydrogen-rich fuel gases that can be more easily utilized, more

efficient, and environmentally-beneficial performance compared with

direct combustion systems.

producer gas

In power generation application, ___ is used either in

dual-fuel mode in diesel engines, or as the only fuel in spark-ignition

engine/gas turbine.

Equivalence Ratio

the ratio of the

amount of air and

stoichiometric air

needed to gasify the

fuel.

Composition of producer gas

CO - 15-30%

H2 - 12-20%

methane (CH4) - 0.5-7%

CO2 - 3-15%

N2 - 50-58%

Wood Chips

Wood Charcoal

Biomass Pellets

Agri-Residues

- Rice Hull

- Coconut shell

- Peanut hull

- Corn cobs

FUEL FOR GASIFIER

Gasification; biogas

___ needs dry materials (wood, paper, hard waste);

___ needs wet or liquid organic waste (manure, food sludges)

Gasification; Biogas

_____ : syngas (carbon monoxide and hydrogen)

_____ : methane and carbon dioxide

b. Biogas

Gas consisting mainly of methane and carbon

dioxide that produces putrefactive bacteria that breaks

down organic material under airless-condition.

a. Biofuel

b. Biogas

c. Gasifier

d. All of the above

b. CH₄ & CO₂

Primary gas produced during anaerobic digestion of

agricultural wastes.

a. CH₄ & H₂S

b. CH₄ & CO₂

c. CH₄ & CO

d. All of the above

a. CO2 and CH4

Gases produced from biogas.

a. CO2 and CH4

b. CO, H2, and CH4

c. CO2

d. All of the above

e. None of the above

c. digester

Biogas is generated inside the ____.

a. gas holder

b. mixing tank

c. digester

d. None of the above

d. None of the above

Gas produced from animal residues consisting of

95% CH4 and 5% CO2.

a. Biogas

b. Producer gas

c. Synthetic gas

d. None of the above

b. 1:1 to 1:2

Feed-material-to-water ratio for optimum biogas

generation is ____.

a. 1:0.5 to 1:1

b. 1:1 to 1:2

c. 1:2 to 1:3

d. None of the above

a. anaerobic digestion

Biogas generation is a process of ____.

a. anaerobic digestion

b. anaerobic gasification

c. fermentation of yeast

d. None of the above

b. 20:1 to 30:1

C-N ratio suitable for anaerobic digestion of

agriwastes.

a. 10:1 to 20:1

b. 20:1 to 30:1

c. 30:1 to 40:1

d. None of the above

e. All of the above

Substrate for biogas production.

a. Poultry manure

b. Piggery manure

c. Cattle manure

d. Agri-plant residue

e. All of the above

f. None of the above

c. Effluent

Residue that comes out of the digester of a

biogas plant after the substrates are digested.

a. Sludge

b. Slurry

c. Effluent

d. None of the above

a. Scum

Layer of floating fibrous material on the slurry.

a. Scum

b. Substrate

c. Sludge

d. None of the above

b. 20 - 25 days

Optimum hydraulic retention time for biogas

production.

a. 15 - 20 days

b. 20 - 25 days

c. 25 to 30 days

d. None of the above

a. shorter

Retention time of pig manure in a biogas digester is

____ than that of chicken manure.

a. shorter

b. the same

c. longer

d. None of the above

b. 80%

Using biogas as fuel for engine can replace ____ of

diesel fuel.

a. 60%

b. 80%

c. 100%

d. None of the above

a. 4800 liters

A biogas digester is to be designed to accommodate

30 liters of dung per day. If the feed-material-to-water

ratio is 1:1 and the designed retention time is 80 days,

what is the capacity of the digester?

a. 4800 liters

b. 5200 liters

c. 6100 liters

d. None of the above

c. 22,500 kg

tunnel-ventilated poultry farm is composed of 5

buildings with 30,000 birds per building. How many kilos

of manure is available in each building if the birds will

stay in there for 30 days? Consider a manure yield of

0.025 kg/day/bird.

a. 18,500 kg

b. 20,875 kg

c. 22,500 kg

d. None of the above

d. All of the above

Biogas can be used for ____.

a. cooking

b. lighting

c. engine fuel

d. heating refrigerant

d. All of the above

e. None of the above

a. 5,500 kcal/m3

Heating value of biogas is around ____.

a. 5,500 kcal/m3

b. 7,200 kcal/m3

c. 9,468 kcal/m3

d. None of the above

c. longer

Retention time of animal manure mixed with plant

materials inside the digester is ____ than that with no

plant materials.

a. shorter

b. the same

c. longer

d. None of the above

d. None of the above

When biogas contains 40% methane and 60%

carbon dioxide, it can ____.

a. be used for cooking

b. be used for lighting

c. run a gas refrigerator

d. None of the above

b. The methane content of biogas is lower than that

of the natural gas.

Which of the following statements is true?

a. The methane content of biogas is higher than that

of the natural gas.

b. The methane content of biogas is lower than that

of the natural gas.

c. The methane content of biogas is the same with

that of the natural gas.

d. All of the above

e. None of the above

b. Bio-latrine

Biogas unit designed to use human wastes as the

principal organic input.

a. Bio-digester

b. Bio-latrine

c. Bio-fermentor

d. None of the above

c. Biofuel

Fuel derived from biomass primarily used for

motive, thermal, and power generation.

a. Bio-Oil

b. Biogas

c. Biofuel

d. All of the above

a. Bioethanol

Biofuel, with chemical formula C2H5OH, produced

from biomass feedstock.

a. Bioethanol

b. Biodiesel

c. Bio-oil

d. All of the above

c. Fermentation and distillation

Process of producing bioethanol from sugar-rich

plant materials.

a. Anaerobic digestion

b. Liquefaction

c. Fermentation and distillation

d. None of the above

b. Yeast

Organism responsible for the fermentation of

sugar into bioethanol.

a. Bacteria

b. Yeast

c. Fungi

d. None of the above

c. 1,350 liters per day

A 10,000liter-per-day-capacity bioethanol plant is

using fermented sap from sweet sorghum with 15%

alcohol. If the plant has 90% distillation efficiency to

produce anhydrous bioethanol, what is the volume of

ethanol that can be derived from the plant in one

day?

a. 967 liters per day

b. 1,250 liters per day

c. 1,350 liters per day

d. None of the above

a. 8,650 liters per day

How much stillage can be derived from the

bioethanol plant in Item above?

a. 8,650 liters per day

b. 9,247 liters per day

c. 9,950 liters per day

d. None of the above

c. Bioethanol

Product resulting from subjecting sugar-rich

biomass to fermentation and distillation.

a. Producer gas

b. Biodiesel

c. Bioethanol

d. Biogas

e. None of the above

b. coconut sap

Bioethanol is produced by subjecting ____ to

fermentation and distillation.

a. coconut oil

b. coconut sap

c. coconut water

d. None of the above