RES 367 Exam 3

Biomass pellets, having a bulk density of 662 kg/m3, are shipped to a combustion plant where they are used to produce energy. If the plant takes in 1026 Mg (1 Mg = 1 metric tonne) of biomass per day, how many trailer-loads are required to deliver this feed per day? The truck weight limit is 24000 kg and the volume limit is 68 m3. Provide the answer to a whole trailer by round to next highest integer.

43

How much power (in kW) is needed to heat 10L of water to increase its temperature from 25 °C to 100 °C in 10 minutes? Note: 1-calorie is defined as the energy it takes to raise the temperature of 1 g of water by 1 °C at atmospheric pressure. The calorie is equivalent to 4.184 J of energy

5.2kW

A modern state-of-the-art biomass power plant with heat recovery feature has the capacity to combust up to 1.3 x 106 kg/day of pellets to generate energy. The pellets have an average LHV of 17.4 MJ/kg and HHV of 19.9 MJ/kg. With a capacity factor of 56% and conversion efficiency of 37%, how much energy does this plant generate on an annual basis? Provide your answer in GWh with at least 3 significant figures.

544

The gas potential for pig manure is 6.0 ft3/lbVS, and the average animal produces 1.30 dry lbs/day of manure which has 0.90 lbVS/dry lbs manure. The energy content of methane gas is 21,433 Btu/lb, and the density is 0.0416 lb/ft3. What is the daily energy potential in the methane produced for one animal? Answer with at least 3 sig figs and in Btu/day?

6260

The biomass is currently being delivered as bales at 1,000.0 US tons per day. The bulk density of the bales is 10.0 lb/ft3. How many truckloads are needed to deliver this much feedstock per day? From lecture you know that the delivery trailer-trucks have a maximum weight limit of 48,000.0 lb or a volume capacity of 3000.0 ft3. Hint: you will need to determine the limiting factor for transporting the baled biomass before calculating the truckloads. Enter as integer, remembering to round to next whole number.

67

In anaerobic digesters, Hydraulic Retention Time (HRT) of the substrate can be defined as the: - digester volume divided by feedstock flow rate -feedstock flow rate divided by feedstock mass -Feedstock mass times feedstock flow rate -volume of liquid in digester divided by volume of solids in digester

- digester volume divided by feedstock flow rate

Calculate the theoretical (maximum) COP for a heat pump that is moving heat by cooling from 33.0 degrees C to 0.0 degrees C. Note: Use the thermodynamic equation: COPcooling = Tcold/(Thot-Tcold) where temperatures are all in absolute units (like degrees K)

8.28

The instructors for this class were: a) awesome b) really awesome c) unbelievably awesome d) all of the above

Just kidding...

What stage of technology is Anaerobic Digestion?

MATURE

Bioenergy fulfills which renewable energy sector needs better than the renewables energy technologies of solar, wind, or geothermal? transportation heating electricity industrial

Transportation

Which of the following are the 3 "primary macronutrients" required for plant growth?

Nitrogen Potassium Phosphorus

About how much biodiesel can I get from 1000 kg of oil? a. 1000 kg b. 900 kg c. 500 kg d. 100 kg

a. 1000 kg

The goal of torrefaction is to create a high yield of a. Biochar b. Syngas c. Methane d. Pyrolysis oil e. Ash

a. Biochar

The following are methods of transforming biomass into fuel (Select all) a. Biological b. Thermochemical c. Genetic modification d. Chemical e. Nuclear

a. Biological b. Thermochemical d. Chemical

What is syngas primarily comprised of (select best answer) a. CO and H2 b. H2 c. H2O and CO2 d. CO

a. CO and H2

Thermalchemical produced biofuels (pyrolysis and gasification) have the following characteristics (select all) a. Can use multiple feedstocks b. Have lower environmental impact than biodiesel and corn ethanol c. Are currently being commercialized d. Allow advanced engine technology

a. Can use multiple feedstocks b. Have lower environmental impact than biodiesel and corn ethanol c. Are currently being commercialized

Gasification creates primarily the following products (select all): a. Carbon monoxide b. Carbon dioxide c. Water d. Hydrogen e. Ash f. Char

a. Carbon monoxide d. Hydrogen f. Char

Why do people use cars vs. human power (biking or walking) for transportation (select all) a. Comfort b. Safety c. Convenience d. Health

a. Comfort b. Safety c. Convenience

What are some advantages of Anaerobic Digestion (select all) a. Produces fuel on waste products b. Does not require feedstocks to be dry c. Methane gas allows for easy separation and conversion to electricity d. Mature technology e. Can produce a large portion of the US energy supply

a. Produces fuel on waste products b. Does not require feedstocks to be dry c. Methane gas allows for easy separation and conversion to electricity d. Mature technology

The advantages of wave energy (select all) a. The energy is free - no fuel needed, no waste produced b. Waves can produce a great deal of energy. c. Easily can withstand rough weather d. Promotes marine habitat

a. The energy is free - no fuel needed, no waste produced b. Waves can produce a great deal of energy.

The global primary use for animal power is a. Transportation b. Electricity generation (treadmill) c. Rotational power (milling) d. Heating (body heat)

a. Transportation

Torrefaction allows the biomass to be transformed into (select all) a. a better solid fuel (more energy dense) b. a more friable fuel (more easily pulverized) c. a cleaner burning fuel d. a liquid fuel

a. a better solid fuel (more energy dense) b. a more friable fuel (more easily pulverized)

Lignocellulosic biomass is primarily comprised of (select all the correct answers) a. cellulose b. hemicellulose c. proteins d. fat e. lignin

a. cellulose b. hemicellulose e. lignin

Which fossil fuel is valued the least (currently has the highest $/GJ) a. coal b. natural gas c. gasoline

a. coal

Carbohydrates in biomass can be converted through hydrolysis to a. sugars b. proteins c. fats d. amino acids

a. sugars

Syngas can be converted into electricity by burning in an engine with a generator? a. true b. false

a. true

Syngas can be converted into liquid transportation fuels through catalytic conversion? a. true b. false

a. true

Syngas can be converted into renewable chemicals through catalytic conversion? a. true b. false

a. true

To use pyrolysis oil for a transportation fuel, it must be upgraded. What are some of the operations that it must undergo? (Select all that apply) Drying to remove water Filtering to remove particulates Stabilization so it does not polymerize Distillation to fractionate Deoxygenation by catalysis

all of the above

How much glucose can I theoretically get from 1000 kg of cellulose? a. 2000 kg b. 1100 kg c. 500 kg d. 100 kg

b. 1100 kg

Why is ethanol such a good renewable transportation fuel (select all correct answers) a. High mpg for car b. Biodegradable c. Does not produce CO2 when burned d. Is commercially blended with diesel e. Biogenic CO2

b. Biodegradable e. Biogenic CO2

Combustion creates primarily the following products (select all): a. Carbon monoxide b. Carbon dioxide c. Water d. Hydrogen e. Ash f. Char

b. Carbon dioxide c. Water e. Ash

More and more dams for hydropower are being installed on rivers in the US a. True b. False

b. False

Which animal is able to output the most energy per day (sustainably) a. Human b. Horse c. Camel d. Mule

b. Horse

Soy-based biodiesel has the following advantages over corn-based ethanol (Select all) a. Need less acreage per gallon of fuel b. Simpler / less energy to convert c. More compatible with transportation fuel infrastructure d. More plants in the US producing biodiesel e. Works better in cold weather

b. Simpler / less energy to convert c. More compatible with transportation fuel infrastructure

The goal of gasification is to create a high yield of a. Biochar b. Syn-gas c. Methane d. Pyrolysis oil e. Ash

b. Syn-gas

Why are scientist interested in cellulosic versus starch based ethanol (select all) a. Ethanol produced is a better fuel b. Uses non-edible feedstocks c. Lignin content allows for easier conversion d. US has potentially ~ 1 billion tons that could be used for supply

b. Uses non-edible feedstocks d. US has potentially ~ 1 billion tons that could be used for supply

Hydropower can be economically used as energy storage for a. Biomass power b. Wind c. Off peak to On peak d. Solar

b. Wind d. Solar

When driving a car most of the energy is used to transport the human a. true b. false

b. false

You currently can make money by converting syngas into products? a. true b. false

b. false

Less developed countries are not a good place to develop renewable energy a. true b. false

b. false (because there is no legacy infrastructure)

Less developed countries energy demand is (select all): a. high per capita b. low per capita c. growing due industrialization d. growing but only with renewable resources

b. low per capita c. growing due industrialization

About how much ethanol can I get from 1000 kg of glucose a. 1000 kg b. 900 kg c. 500 kg d. 100 kg

c. 500 kg

Where does the energy for human or animal power come from a. Muscles b. Will power c. Food calories d. Oxygen

c. Food calories

What is a "developing country"? a. Country developing renewable energy b. Countries with rapidly expanding economies c. Poor or middle income countries d. Countries outside of "industrialized world"

c. Poor or middle income countries d. Countries outside of "industrialized world"

Which fossil fuel is valued the most (currently has the highest $/GJ) a. coal b. natural gas c. gasoline

c. gasoline

Are the following a primary component of lignocellulosic biomass? Mark yes or no for each option. cellulose hemicellulose lipids lignin protein starch

cellulose: YES hemicellulose: YES lipids: NO lignin: YES protein: NO starch: NO

Which feedstocks are suitable for pyrolysis or gasification? woody biomass grasses coal natural gas

woody biomass grasses coal

One advantage of using Pyrolysis, Torrefaction and Carbonization of biomass feedstocks is.. -All of these processes increase the energy density of the Biomass Feedstock and therefore, reduce transportation cost and energy use -All of these processes retain all of the energy value of the biomass. -All of these processes require no energy input for the transformation of biomass.

-All of these processes increase the energy density of the Biomass Feedstock and therefore, reduce transportation cost and energy use

The moisture contained in biomass introduces the following difficulties for its use as a fuel (select all that apply -Biomass may spoil during storage -When used for combustion, recovery of the energy from this moisture adds cost and complication. -The extra weight of the water increases transportation cost and difficulty. -The energy converted to steam during combustion cannot be recovered.

-Biomass may spoil during storage -When used for combustion, recovery of the energy from this moisture adds cost and complication. -The extra weight of the water increases transportation cost and difficulty.

In addition to electrial energy production, which of the following are benefits of anaerobic digestion (mark all that apply): -Reduces Nitrogen and Phosphorous in waste stream -Both Solid and liquid digestate fractions can be used as fertilizer. -Digested solids can be used as animal bedding -Reduce odor produced by manure -Reduced greenhouse gas emissions from dairy farms -Reduced pathogen population in digestate

-Both Solid and liquid digestate fractions can be used as fertilizer. -Digested solids can be used as animal bedding -Reduce odor produced by manure -Reduced greenhouse gas emissions from dairy farms -Reduced pathogen population in digestate

The desired characteristics of biomass used in a thermal conversion process include... -High Energy Density -Low Moisture Content -High ash levels -High percentage of green leafy material

-High Energy Density -Low Moisture Content

What would happen if the operating temperature of an anaerobic digester is gradually increased from 20oC to 60oC? -The digestion rate decreases because the microorganism activity is inhibited due to high temperature. -The digestion rate increases because compounds are broken down faster thermochemically. - The digestion rate increases because the same community of microorganism is more active. -The digestion rate increases because a different community of microorganism would become active.

-The digestion rate increases because a different community of microorganism would become active.

How does a higher moisture content of biomass impact the industries that use thermal conversion processes (combustion, pyrolysis, & gasification)? (select all that apply) -It increases the hydrogen produced during gasification. -It lowers the heating value as energy is required to dry the biomass -It facilitates the pyrolysis by lowering temperatures required -It results in higher transportation costs

-It lowers the heating value as energy is required to dry the biomass -It results in higher transportation costs

Why would planting alfalfa require no nitrogen fertilizer? -Legumes such as alfalfa can fix nitrogen from the atmosphere -Alfalfa does not require nitrogen for plant growth -They are a C3 plant that thrive in cool climates, requiring no additional nitrogen -Alfalfa is an perennial plant

-Legumes such as alfalfa can fix nitrogen from the atmosphere

Feedstock logistics systems challenges include: (select all that apply) -Low mass density and energy density -Moisture content at the time of harvest or collection leads to degradation -Quality characteristics are variable and inconsistent -Transportation is costly and can strain transportation networks -Chemical components are not suitable for fuels

-Low mass density and energy density -Moisture content at the time of harvest or collection leads to degradation -Quality characteristics are variable and inconsistent -Transportation is costly and can strain transportation networks

To maximize the amount of liquid oil produced during thermal degradation, the following conditions should be met. -Temperature round 600C, slow heat rate -Temperature around 600C, fast heat rate -Temperature 1000C, slow heat rate -Temperature 1000C, fast heat rate

-Temperature around 600C, fast heat rate

1000.0 kg per minute of water is released through a dam to generate electricity continuously. The drop of the water is 12 m and has negligible friction. Calculate how much energy (in kWh/day) can be generated on a daily basis, if the turbine is 80.0% efficient.

38 kWh/day

A wood processing plant would typically have _______ months of storage of biomass. 1-2 <1 12 6

1-2

Water in the Dead Sea has a density of 1,204 kg/m3. How much power (in MW) is converted from kinetic energy to electrical energy in rotating the turbine (diameter of 10m) if the water flows in at 7.00 m/s and out 3.00 m/s and the overall conversion efficiency of the turbine is 80%?

11.9MW

Water in the Dead Sea has a density of 1,204 kg/m3. How much power (in MW) is converted from kinetic energy to mechanical energy in rotating the turbine (diameter of 10m) if the water flows in at 7.00 m/s and out 3.00 m/s?

14.9MW

Place the following steps in order for solid fuel combustion (1 is first and 5 last) Heating Flaming Combustion Pyrolysis Char Combustion Drying

14352

MGE's Blount Generating Station has a capacity of 100.0 MW (electricity produced), and combusts natural gas to generate this power. How much biomass is needed on a daily basis to convert this plant to a biomass combustion facility? Assume a heating value of the biomass fuel of 16,720 kJ/kg and a conversion factor of 0.350. Provide answer in Mg/day (Mg is the same as metric tonne) with at least 3 sig figs.

1476

Water in the Dead Sea in the Middle East, thanks to its very high salt concentration, has a density of 1,204 kg/m3. How much power (in MW) is available in the flowing water flowing at 7.00 m/s flowing through a turbine with a diameter of 10m ?

16.2MW

You are burning wood to heat water for your industrial process. What is the mass of wood required to raise the temperature of 1000 kg of water from 25.0 to 100.0 °C (in kg with at least 3 sig figs.)? The specific heat of water is 4.184 J/g°C, and the lower heating value of dry wood is 16.72 MJ/kg.

18.8

If the biomass in the previous problem was delivered as pellets instead, the bulk density is 36 lb/ ft3. How many truckloads would be required to deliver the same 1,000 tons of biomass to the plant each day? Hint: Remember to determine first whether the weight or the volume is going to be the limiting factor in this case. Enter as integer, remembering to round to next whole number.

42

If you hydrolyze and ferment 350 kg of cellulose how many kg of ethanol can you theoretically produce?

198 kg

It would take about ___ full semi-truck loads to transport 100,000 lbs DM of pelleted corn stover 9 5 2 1

2

If a modern power plant burns 1 million metric tonnes of natural gas in a year, about how much CO2 is added to the atmosphere? (in million tonnes) a) 1.5 million tonnes b) 2.5 million tonnes c) 3.5 million tonnes d) 4.5 million tonnes

2.5 million tonnes

A biomass combustion plant with a nameplate capacity of 100.0 MW, and a capacity factor of 0.50 utilizes pellet fuel with an energy content of 19.5 MJ/kg. What is the mass of fuel that is required on a daily basis (in tonnes/day)

222

A vehicle can average 40 hp cruising for a period of 4 hours on a full tank of gasoline (14-gal). Assume the energy content of gasoline to be 20,000 Btu/lb, and a gasoline density of 6.073 lb/US-gal. How efficient is said truck at converting the fuel into usable work (in %)? Assume: 1 kWh = 3,412.4 Btu, and efficiency is defined as the energy output/ energy input

23.6%

Chicken litter has a heating value of 2400.0 Btu/(dry lb) at the 28.0% solids content. Instead of converting to biogas, how much thermal energy per day can be produced through combustion of the one hen's daily biomass (from the previous question)? Answer with at least 3 sig figs and in Btu/day.

235

A corn ethanol production plant receives 600 tonne/day corn feedstock at a moisture content of 20.0% (wet basis). If all of this corn is converted into ethanol what is the most volume (theoretical volume) of ethanol that this facility can produce per day (m3/day). Assume that the starch content of corn grain is 70.0%. The density of ethanol is 789 kg/m3.

241

The methane potential for chickens is 4.30 ft3/lb volatile solids, and the litter (fancy name for chicken manure) has a total solids content of 28.0%, of which 65.0% are volatile solids. Assume that a single hen produces 0.35 pounds of litter per day. What is the daily energy potential in the methane produced via AD for one hen? Assume the energy content of methane gas is similar as the pig manure questions at 21,433 Btu/lb and a density is 0.0416 lb/ft3. Answer with at least 3 sig figs and in Btu/day?

244

The maximum weight capacity of a chip van semi-trailer is 80,000.0 lb, whereas the volume capacity is 4,000.0 ft3 . How many truckloads are necessary to deliver 1,000.0 tons of biomass pellets of bulk density 40 lb/ft3 per day to a biomass combustion facility (number of truckloads per day, round to nearest integer)? 1 US ton is equal to 2,000.0 lb.

25

The maximum weight capacity of a chip van semi-trailer is 80,000.0 lb. How many truckloads are necessary to deliver 1,000.0 tons of biomass per day (number of truckloads per day)? 1 US ton is equal to 2,000.0 lb. Enter as integer, rounding to next whole number. For example if you had 11.2 trucks you would need 12 trucks as you can't have 0.2 trucks.

25

Using the information from the previous two problems, what is the percent increase in the energy density that is achieved by densifying the baled biomass into pellets? Because the pellets are further dried they have an increase heating value (bale biomass = 16,720 kJ/kg and pellet biomass = 18,400 kJ/kg). Answer in % with at least 3 sig figs. Hint: From lecture we know the energy density is expressed as the energy content on a volumetric basis (units of energy/volume).

296

The state of Wisconsin's swine count is 1.12 million. What is the annual electrical energy that can be generated by the anaerobic digestion of swine manure produced in the state? Assume the conversion from chemical to electrical energy for the methane is 40.0% efficient. Answer with at least 3 sig figs and in GWh/year?

299

"Syn-Gas" produced by gasification of biomass can be used for -combustion for process heat or electrical generation. -conversion to methanol -feedstock for diesel or gasoline production -production of hydrogen for other reactions

ALL OF THE ABOVE

Which of the following feed stocks can be used in the anaerobic digestion process? -Animal Manure -Municipal Waste Water -Grasses -Food waste -Energy crops

ALL OF THE ABOVE

Match the technologies to their potential applications Anaerobic Digester Pyrolysis Gasification Pelleting ------------------------ Bio-gas producing syngas producing bio-char and bio-oil producing solid fuel

Anaerobic Digester: Producing Bio-gas Pyrolysis: producing bio-char and bio-oil Gasification: producing syngas Pelleting: producing solid fuel

Which type of plants are best at producing starch and simple sugars and also require plentiful sunlight and water? C4 plants C3 plants Woody plants Herbaceous

C4 Plants

Biomass fed to a boiler that has inadequate air for complete combustion of all the biomass. Select all of the products that are produced. Carbon dioxide (CO2) Carbon (C) Carbon monoxide (CO) Water (H2O) Nitrogen (N2)

Carbon dioxide (CO2) Carbon (C) Carbon monoxide (CO) Water (H2O)

The highest solar insolation occurs in the Southwestern USA while, the highest rainfall occurs in the Southeastern USA. Which of The following regions produces the most biomass per hectare? Central plains region where good solar insolation and good rainfall over lap Southwestern United States Southeastern United States Alaska

Central plains region where good solar insolation and good rainfall over lap

Choose which condition belongs to gasification and which to combustion. Excess air is supplied to reaction Temperatures can be >1000 C 'Reaction products are fully oxidized H and CO are the primary products

Excess air is supplied to reaction : COMBUSTION Temperatures can be >1000 : BOTH 'Reaction products are fully oxidized : COMBUSTION H and CO are the primary products : GASIFICATION

Bio-oil is processed in the way the crude petro oil is T/F

FALSE

Crops grown in the field and forest residue are the only types of biomass feedstock for bioenergy T/F

FALSE

Biomass has higher oxygen content than petroleum fuels T/F

TRUE

Biomass has less combustion calories per kg than petroleum based fuels T/F

TRUE

The main difference between the process of Gasification and Pyrolysis is: (select the best answer) -The feedstock is different. -There is no difference in the process because they happen together. -The amount of air supplied is different. -The water content is different.

The amount of air supplied is different.

The density of a material is the mass per volume of 'one piece' of the material. The bulk density of the same material is... Hint: this is review from the last module The weight to volume ratio of a 'pile' of the material and resulting voids. The density when many pieces are submerged under water. The density of the material before it is dried.

The weight to volume ratio of a 'pile' of the material and resulting voids.

The last biomass material to thermally degrade is ____?

char

About how much methanol is needed to make 1000 kg of biodiesel? a. >1000 kg b. 900 - 1000 kg c. 500 - 600 kg d. 100 - 200 kg

d. 100 - 200 kg

Hydropower relies on what energy conversions to make electricity a. PE to Electricity b. KE to Electricity c. PE to Rotational to Electricity d. PE to KE to Rotational to Electricity

d. PE to KE to Rotational to Electricity

The goal of fast pyrolysis is to create a high yield of a. Biochar b. Syn-gas c. Methane d. Pyrolysis oil e. Ash

d. Pyrolysis oil

Another more specific term for biomass that is of interest for bioenergy is a. wood b. grass c. cellulosic d. lignocellulosic

d. lignocellulosic

What is required to perform hydrolysis on carbohydrates? a. catalyst b. temperatures >500C c. abscence of oxygen d. water and a catalyst

d. water and a catalyst

The conversion of solar energy into stored chemical energy in a plant through the process of photosynthesis is approximately how efficient 28% 7.2% 4.3% less than 1%

less than 1%