washington state university-chhp system design

7/31/2019 Washington State University-CHHP System Design

http://slidepdf.com/reader/full/washington-state-university-chhp-system-design 1/39

!

Manuel Garcia-PerezCougsCARE

Clean And Renewable Energy at WSU

Washington State University’s CHHP System Design and Report

April 2, 2012

By

M. Brennan Pecha, Eli J. Chambers, Cale Levengood, Jacob Bair, and

Shi-Shen Liaw

Faculty Advisors: Dr. Jacob Leachman, Dr. Su Ha, and

Dr. Manuel Garcia-Pérez



i

Executive Summary

Whitman County, Washington, home of Washington State University (WSU), has been the highest

wheat-producing county in the United States every year since 1978. The low net worth of straw,

combined with the lack of demand for this waste product of wheat farming, provides little incentive to

harvest it. Rather than harvesting, farmers often burn the straw, releasing CO 2 and other pollutants into

the air. Our proposal will help to minimize this practice and create clean energy through a series of

thermochemical conversion pathways. These well-studied technologies combined with the close

proximity of this untapped biomass to existing WSU facilities creates an outstanding opportunity for

Cogeneration of Heat, Hydrogen, and Power (CHHP) on our campus and community. i

This report lays out the design for a trigeneration system utilizing FuelCell Energy’s DFC3000 molten

carbonate fuel cell that integrates within the established infrastructure of the WSU campus. The best way

to produce CHHP is through thermochemical degradation. The wheat straw will be initially heated in a

pyrolysis reactor, producing char and pyrolysis vapor. Char will be converted into hydrogen through

gasification. A methanation reactor then converts hydrogen and carbon monoxide into methane. The

methane concentration will then be raised with a water gas shift reactor, a carbon dioxide scrubber, and a

hydrogen separation membrane. The synthetic natural gas will then be fed to a molten carbonate fuel cell

unit, which reforms the gas and creates electricity. Residual hydrogen gas can be separated from the

exhaust and used for other purposes.

The CougsCARE (Clean And Renewable Energy) facility will produce up to 3,945 kilograms of pure

hydrogen per day, cut down the natural gas requirement of the WSU steam plant, and add 4.4 MW of

electricity to Pullman’s power grid. Nearly 3.5 MW of heat can also be extracted to heat established

greenhouses immediately adjacent to the proposed facility. The facility will also produce excess pyrolysis

vapor and ash. The pyrolysis vapor will supplement natural gas at the steam plant and decrease fossil fuel

CO2

emissions. Ash has the potential for further upgrading to useful chemicals.

The immediate environmental benefits of this system are immense and provide high potential to become

profitable as clean energy becomes more important. The initial large capital investment of $24,531,290

required to setup the facility is justified by its lasting impact on the environment and community as it

clears the way for the development of a hydrogen economy. From operational and straw costs, the system

would lose $1,390,200 in 2012. However, if there is a carbon tax and fuel prices continue to rise, the

projected profits in 2020 will be $2,212,220.

An environmental analysis of this facility shows that by utilizing the pyrolysis vapor in steam generation

and incorporating hydrogen in campus vehicles, CO2 emissions will be decreased by 54,000 tons per year.

Analyses show that the plant location will keep the community safe and hydrogen gas will not be a threat

to public safety.

This process is highly beneficial for the entire community: (1) it minimizes air pollution to benefit overall

community health, (2) it creates clean energy to supplement the grid of an expanding WSU campus, and

(3) it finally gives Whitman County farmers a use for their wasted straw. All resources necessary for this

process are easily accessible on the WSU campus, making this proposition an incredible opportunity for

co-generation of clean Hydrogen, Heat, and Power.



ii

Table of ContentsExecutive Summary i

1 Resource Assessment and Transport of Straw 1

2 Technical Design 2

2.1 Process Identification 2

2.1.1 Rotary Cutter 22.1.2 Pyrolysis Reactor 2

2.1.3 Pyrolysis Vapor Distribution 5

2.1.4 Gasification Reactor 52.1.5 Methanation Reactor 6

2.1.6 Water Gas Shift Reactor 72.1.7 CO2 Scrubber 8

2.1.8 Hydrogen Separation Membrane 1 8

2.1.9 DFC Reformer and Anode 9

2.1.10 Hydrogen Separation Membrane 2 10

2.1.11 Recycling CO2 to the Cathode 10

2.1.12 Recycling Hydrogen to the Methanator 11

2.1.13 Hydrogen Compression and Storage 11

2.1.14 Electricity Integration 11

2.1.15 Heat Distribution 112.2 System Heat and Mass Balances 122.3 Equipment Selection 14

2.3.1 Pyrolysis Reactor 152.3.2 Gasification Reactor 15

2.3.3 Methanation and WGS Reactors 16

2.3.4 Hydrogen Separation Membranes 16

2.3.5 DFCs 16

2.3.6 Hydrogen Compression 16

2.3.7 Hydrogen Storage 16

2.3.8 Hydrogen Dispensers 17

2.3.9 Material Distributers 17

2.3.10 Electricity Integration 17

2.3.11 Heat Transfer Equipment 173 End Uses 18

3.1 Hydrogen 18

3.1.1 Transportation Fuel 18

3.1.2 Recycling Hydrogen to Methanator 20

3.1.3 Fertilizer Production 20

3.1.4 Additional Hydrogen End Uses 20

3.1.5 Available Diversification 20

3.2 Heat 20

3.3 Power 21

3.4 Ash 21

3.5 Pyrolysis Vapor 224 Safety Analysis 22

4.1 Classification of Dangers 224.2 Plant Location 22

4.3 System Monitoring and Process Control Instrumentation 22

5 Economic Analysis 23

6 Environmental Analysis 25

7 Education and Marketing 26

7.1 Education 27

7.2 Marketing 27

Appendix 29

References 34



!

P a g e | 1

!

WheatStraw,

291,517

Other FieldResidue,

10,750

Grass SeedStraw,

8,681

BarleyStraw,

147,605

Figure 1.1 Field Biomass Residue in

Whitman County (tonnes/year)

Figure 1.2 Plant and Straw Storage Location

1 Resource Assessment and

Transport of Straw

CougsCARE will use wheat straw as its primary

feedstock.

Approximately 291,517 tonnes1

of dry wheat

straw result from the immense wheat harvest

each year. The available biomass breakdown for

2005 in Whitman County is shown in Fig. 1.1.ii

Included in this breakdown are the 147,605

tonnes of barley straw and 8,681 tonnes of grass

seed straw produced annually, which could

serve as secondary sources of fuel for our

system.iii

The delivery and storage of straw is a relatively simple process which has been in practice for over 150

years on the Palouse, the fertile region in which Whitman County is located. It is common to bail the

straw into rectangular cuboids, to minimize packing volume. Semi-trucks transport the straw from

surrounding areas to where it can be stored in stacks with tarp coverings to reduce moisture intake. The

estimated yearly cost is $10 per tonne to transport and $12 per tonne to store. Sometimes livestock

owners buy straw for bedding for $45-

60 per tonne (depending on the

quality), although few wheat farmers

are fortunate enough to sell any of it.

Most farmers do not bother to even

collect the straw for this reason. For

our process, the total cost of the

purchase, delivery, and storage of

straw ranges from $70-85 per tonne.iv

At a feed rate of 1.2 kg/s of wheat

straw, the facility requires about

36,050 metric tonnes of straw per

year. Therefore, this system would

consume approximately 12.3% of the

available wheat straw on the Palouse.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1 Tonne=1000 kg



!

P a g e | 2

!

Wheat straw has a density of approximately 120 kg/m3. This means CougsCARE would need 300,000

cubic meters of straw per year. To avoid the fire hazard of storing so much straw in one area, farmers can

periodically deliver straw so that there will be at least two weeks’ worth of operating feedstock on the

premises at all times. Fig. 1.2v

shows the plant location and straw delivery spot and storage area.

It is important to note that there is plenty of space available for straw storage and an operational facilitynext to the steam plant. A large hill also stands between this location and all surrounding residences,

protecting nearby homes from any plant failures.

2 Technical Design

The overall goal of the project is to produce Cogeneration of Hydrogen, Heat, and Power (CHHP). With a

lignocellulosic feedstock of wheat straw, controlled chemical conversion is the most feasible solution. Fig

2.1 on the next page shows the overall Process Flow Diagram (PFD) for the system.

2.1 Process Identification

This section describes the philosophy and logic behind the process order. The numbers in this section

correspond to numbers on the PFD in Fig. 2.2. Fig. 2.3 shows a simplified 3-D plant layout.

2.1.1 Rotary Cutter

The first step in the process involves dumping the straw from the storage location into a large hopper and

chopping it up to fine particulate matter. This increases the surface area of the particles, which will

increase the rate of conversion to biochar in the pyrolysis reactor.

2.1.2 Pyrolysis Reactor

The technology of lignocellulosic biomass

pyrolysis has been used for centuries to produce

charcoal (biochar). Since the beginning of 20th

century, pyrolysis vapor from the reaction has

been condensed for the commercial production of

solvents, chemicals and fuels. Fig. 2.1vi

shows a

basic pyrolysis reactor flow diagram.vii

Pyrolysis is typically performed at temperatures

between 400 and 600 °C in the absence of oxygen. In these conditions the biomass particles are heated

and vapors produced can escape from the biomass. The resulting products are bio-char (20-40 mass %)

and pyrolysis vapor (60-80 mass %).

In a commercial concept, the vapor produced is commonly used as an energy source to heat the pyrolysis

reactor through a combustion chamber. Therefore this reactor will operate at 500 ºC and about 1 bar.viii

Figure 2.1 Pyrolysis Reactor Flow Pattern



!

P a g e | 3

!

Figure 2.2 Process Flow Diagram



!

P a g e | 4

!

CougsCARE

Washington State University’s Clean And Renewable Energy

Facility

Figure 2.3 3-D Simple Site Diagram



!

P a g e | 5

!

2.1.3 Pyrolysis Vapor Distribution

The pyrolysis vapor (or biovapor) is produced in

excess. One great property of pyrolysis vapor is its

combustibility, as can be seen in Fig. 2.4ix. This can be

sent to furnaces for heating the pyrolysis andgasification reactors. This saves an extraordinary

amount of energy and fossil fuel emissions. Because of

this, the entire system does not require a net input of

electricity or fossil fuels.

The quantity of excess pyrolysis vapor is so large that,

even after heating the pyrolysis and gasification

reactors, it can be sent to the adjacent Grimes Way

Steam Plant. The steam plant currently heats steam for the campus using natural gas. Pyrolysis vapor can

supplement this natural gas and offset the cost and emissions of the steam plant.

2.1.4 Gasification Reactor

The next reactor is called a gasification reactor.

Combining char with water at high temperatures

produces syngas, a mixture of H2 and CO. The

seven possible reactions that commonly occur in

gasification reactor are shown in Table 2.1x below.

Fig. 2.5 shows a basic flow schematic for a

gasification reaction.

The primary reaction in this process is the water-gas reaction (R3). The reaction enthalpy can be

estimated as 7429 kJ/kg char with 68 mass % of

carbon.

C + H2O! H2 + CO

In industry, a gasification reactor is generally heated by combusting some of the biochar. This requires

oxygen and releases CO2. However, our reaction will be heated externally by a pyrolysis vapor furnace

and no oxygen will be added in the gasifier, resulting in no CO2 being released.

The water-gas reaction requires steam. All of the steam will be produced from excess heat in the CHHP

system. One of the great advantages of this project is that steam is already present in high amounts at the

steam plant, which is rarely running at its full capacity. We can therefore inject steam from the plant

directly into the gasification reactor if there is not enough steam produced internally.

The operating conditions in the gasification reactor, optimized by researchers, has been found to be 700

ºC and 1.25 kg steam/kg char for the best conversion.xi

The char entering the gasification reactor contains 32 mass % of ash. The ash does not disappear. It will

particularize and float up and out of the reactor with the syngas. The most common way to remove the ash

Figure 2.4 Pyrolysis Vapor Combustion

Figure 2.5 Gasification Reactor Depiction



!

P a g e | 6

!

is with a vortex-centrifuge, which spins the gas within a cone so the heavy particles (ash) drop out the

bottom while the gas comes out the top.

Usability of the ash will be discussed in End Uses.

Reaction ! Hr,

298 K

(kJ/mol)

! Gr, 298

K (kJ/mol)

Reaction Name

R1 C + O2 ! CO2 -393.5 -394.4 Complete carbon oxidation

R2 C + 1/2O2 ! CO -110.5 -137.2 Partial oxidation of carbon

R3 C + H2O! H2 + CO 131.3 91.4 Water-gas reaction

R4 C + CO2 ! 2CO 172.5 120.1 Boudouard reaction

R5 C + 2H2 ! CH4 -74.8 -50.8 Carbon hydrogenation

R6 CO + H2O! H2 + CO2 -41.2 -28.7 Water-gas shift reaction

R7 CO + 3H2 ! H2O + CH4 -206.1 -142.2 Reverse methane reforming

reaction

Estimated Conversion

In an optimized system, all of the carbon in the char is converted into syngas.

2.1.5 Methanation Reactor

The methanation reactor (methanator) converts hydrogen and carbon monoxide into methane and water;

the products are known as synthetic natural gas (SNG). The primary reaction is the reverse methane

reforming reaction, shown in Fig. 2.6.

CO + 3H2 ! H2O + CH4

It might seem curious to convert hydrogen back into methane, but the design of the DFC requires it. The

reformer in the DFC converts methane or other hydrocarbons into hydrogen and carbon monoxide. If

there is too much hydrogen in the feed, the fuel cell overheats since it has nowhere to balance its heat.

Therefore, the gas or liquid fed to the DFC cannot contain more than 50 mole % of hydrogen and must

have at least 50 mole % of methane on a dry basis.xii

Another reason to add a methanation reactor involves the heat balance for the system. The methanation

reaction is highly exothermic, so the heat can be pulled off in the cooling loop, as will be discussed in

section 2.1.14.

The methanation reactor also requires a catalyst for high and fast conversion. Researchers and industry

have shown that catalyst with a high nickel load (~60%) works well.xiii

Table 2.1 Important gasification reactions



!

P a g e | 7

!

Although fluidized bed reactors have the best conversion, compared with fixed bed reactors, fluidized bed

reactors are difficult to manage due to their dynamic nature. Therefore, CougsCARE will use fixed bed

reactors.xiv

This system will utilize four fixed bed reactors in series with heat exchangers between the reactors,

similar to the design seen in Fig. 2.6xv

.


A PRO/IIxvi reaction simulation was used to estimate the reduced Gibbs equilibrium. The assumption

made was that the reaction will reach complete equilibrium. A stream of 50% H 2 and 50% CO at 300 ºC

gave 99.9% conversion of hydrogen into product CH4 and H2O.

2.1.6 Water-Gas Shift Reactor

This reactor converts carbon monoxide and water to hydrogen and carbon dioxide.

The reason that this reactor is necessary is that the composition of methane in the synthetic natural gas istoo low, even on a dry basis. Why can’t the carbon monoxide be removed to increase methane

concentration? It is because CO and CH4 have very similar properties and are very expensive and

complicated to separate.xvii

There are well-tested processes for separating CO2 from CH4 that do not involve such delicate

complexity. Converting CO to CO2 can be done with a water-gas shift reaction (WGS) shown below.

CO + H2O! H2 + CO2

This is a slightly exothermic reaction, for which likely reactor temperature would be 300 ºC. The heat will

be transferred from the reactor through the same cooling loop used for the methanation reactor.

The WGS reactor requires a Cu/Zn/Al catalyst for high and fast conversion and will take place in a series

of two fixed bed reactors.xviii


Simulation of this process in PRO/II with a reduced Gibbs energy reactor gave 97% reaction conversion,

assuming complete equilibrium is reached.

Figure 2.6 Methanation Reactor Layout



!

P a g e | 8

!

2.1.7 CO2 Scrubber

This CO2 scrubbing step removes some

of the CO2 from the water-gas-shifted

synthetic natural gas.

A CO2 scrubber takes advantage of the

differences in solubility of the various

stream components in water. The WGS

outlet stream will be sent through an

adsorption column to be scrubbed using

a recycled water loop. Fig. 2.7 shows

the process flow for a CO2 scrubber.

The adsorption column will be packed

with 25 mm spherical packing. The gas

stream will initially be pressurized toabout 6 bar before being cooled by the

system cooling loop.

The scrubbing water will be sent

through a flash separator after exiting

the tower to strip out the CO2. Then it

will be cooled in a chiller and pumped

back into the top of the adsorption

tower, where it will cool the gas stream.xix

Through this process, the CO2 content

of the steam can be reduced to roughly

2%, if desired.

Component balance

The CougsCARE system only needs to remove 15% of the CO2 to meet CH4 concentration requirements.

2.1.8 Hydrogen Separation Membrane 1

Although the methane concentration has been raised,

the synthetic natural gas still contains too muchhydrogen for the DFC to operate efficiently, based on

required performance specifications.

Separating hydrogen from the stream is actually quite

simple. Since hydrogen is a small molecule, it can be

essentially filtered from other molecules via size-

exclusive membranes. Fig. 2.8 shows a general

separation schematic.

Figure 2.8 Hydrogen Separation Membrane

Figure 2.7 CO2 Scrubber Schematic



!

P a g e | 9

!

The driving force for separation is a pressure difference on either side of the membrane, so the feed will

be compressed to about 8 bar with a centrifugal oil-free compressor.

Component balance

Using this system, about 90% removal of H2 can be expected with permeating hydrogen at nearly 100% purity. This hydrogen is pure enough to used in transportation vehicles.

The SNG leaving the membrane now has a composition of more than 50% CH 4. This is a satisfactory

composition of methane to enter the DFC.

2.1.9 DFC Reformer and Anode

The Direct Fuel Cell (DFC) system works in essentially two stages. First, the feed fuel (methane, in our

case) is reformed into hydrogen through the methane reforming reaction (R7). This hydrogen-rich gas

then enters the anode side of a fuel cell. At the anode, H2 is oxidized by CO3-to release electrons into the

anode. On the cathode side, CO2 is reduced to CO3-by O2 and electrons.

Molecular and electron flow patterns in the molten carbonate fuel cell can be seen in Fig. 2.9xx

.

This creates an electric potential from which electricity can be drawn and sent to the campus power grid

by the electrical balance of plant (EBOP).

Integrating the electricity back into the grid will be

discussed in detail in section 2.1.14.

Electrical Output Calculation

The electrical output of the DFC can be calculated

based on the product specification for theDFC3000. Since the DFC consumption of methane

is 362 scfm2

and the power output is 2800 kW, the

energy conversion is 7.73 kW/scfm of methane. In

mass based units, 2.45 MJ/kg methane.

Anode Outlet Gas (AOG) Composition calculation Assuming all the methane entering the DFC system

is converted to hydrogen on a 1-mole methane

basis, the overall reactions at the anode result in the

following anode exhaust (AOG) molar flow:

0.93H2 + 3.07H20 + 0.47CO + 3.13CO2

Molar flow-rates from this equation are added to

the components in the incoming stream that do not

react at the anode surface. More details on this

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"!Scfm=0.01996 gmol/s methane!

Figure 2.9 Molecular Flow in a Molten

Carbonate Fuel Cell



!

P a g e | 10

!

calculation can be seen in the Appendix.

2.1.10 Hydrogen Separation 2

Only 65% of the hydrogen gas created in the reformer is consumed at the fuel cell anode. This leaves the

system with another opportunity to extract hydrogen gas.

The AOG is at a temperature of about 600 ºC and needs to be cooled to around 100 ºC before entering the

compressor so the separation membrane does not melt.

As with the first membrane, about 90% of the hydrogen can be separated. However, this hydrogen will

not be as pure as the hydrogen from the first membrane due to higher concentrations of other components.

All hydrogen from this component will be sent to the methanation reactor. More on hydrogen distribution

will be discussed in section 2.1.12.

2.1.11 Recycling CO2 to the Cathode

The cathode side of the fuel cell requires a constant flow of CO 2 and oxygen. Fortunately, the gas comingout of the retentate from the H2 separator contains plenty of CO2. The following equation relates how

much CO2 is used by the fuel cell cathode.

"O2+ CO2+ 2e- ! CO3

2-

CO + O2 + 2e-! CO3

2-

On the anode side, the carbonate is utilized according to the following equations.

CH4 + 2H2O! 4H2 + CO2

H2+ CO3

2-

! H2O + CO2

For every 1 mole of methane consumed at the

anode, about 3.6 moles of CO2 are consumed at

the cathode.

Notice that oxygen is also required, so it will

have to be added into the stream. This can be

done by first throttling the gas coming out of

the H2 separation membrane back to about 1

bar, then forcing air in at positive pressure.

This way, the exhaust gas will not escapethrough the air vent. Fig. 2.10 shows a basic

outline of this process. Since air is only 21%

oxygen, 9.52 moles air/mole CH4 are required.

The final exhaust composition contains about 3% hydrogen. Fortunately the flammability limit of

hydrogen is 4%, so there is little concern for combustion at the exhaust port. The high diffusivity of H 2 in

air also lowers the risk of hydrogen accumulation in case of a leak.xxi

Figure 2.10 Adding Air to Cathode Recycle



!

P a g e | 11

!

Figure 2.11 Cooling Water and Steam Flow Diagram

2.1.12 Recycling Hydrogen to Methanator

As will be discussed in the End Uses section, there will be more hydrogen produced than is demanded for

vehicles. Therefore, hydrogen permeate can be recycled to the methanation reactor feed to increase the

conversion of CO and H2 to CH4.

2.1.13 Hydrogen Compression and Storage

The difficult part of dealing with hydrogen is pumping and storing it. There are currently a few ways to

store hydrogen. One is by storing it as liquid hydrogen in insulated vessels. However, this process is

expensive and there is product loss due to evaporation. Liquefying hydrogen is excellent for transporting

bulk H2 long distances. However, bulk transportation is not necessary for our system. In this case, storage

of hydrogen at high pressures in the gas phase will be the least expensive option, since the refueling

station will be adjacent to the plant.

Most hydrogen vehicular tank pressures are at 350 bar (5000 psi). Therefore, we must pump the hydrogen

to about 440 bar to be able to fill tanks fast.xxii

It is reasonable to have enough immediate storage for 5 days worth of hydrogen vehicle usage in case of

repair time.

The hydrogen can be dispensed to buses or automobiles by fuel dispensers at 350 bar.

2.1.14 Electricity Integration

A transformer will be necessary to ensure electricity produced in our facility is consistent with the local

grid’s voltage and phase, as well as safety equipment to ensure electricity flows in the proper direction.

Our net power output will be slightly less than total electricity produced due to parasitic losses for pumps,

compressors, and other units used in our power generation cycle.

2.1.15 Heat Distribution

The methanator and WGS

reactors both produce large

quantities of heat. This heat

will be utilized along with the

exhaust heat of the DFC3000

units to heat water streams for

the gasification unit and a

heating loop for the nearby

WSU campus greenhouses.

Fig. 11 shows the cooling

loop schematic and Fig. 12

shows the breakdown of

coolant water distribution.

The returning water from the

greenhouse heating loop will



!

P a g e | 12

!

Methanationand WGS

Cooling

Water

37%

DFCCooling

Water

33%

DFC FeedWater

5%

Steam toGasifier

5%

EvaporatedWater

Make-up

20%

Figure 2.12 Distribution of Cooling Water Flow

be cooled in a large cooling tower to roughly 25 °C before being once again pumped through the cooling

loop.

Initially, the 25 °C water will be pumped from the basin at the bottom of the cooling tower to a distributer

which will split off a portion to the methanator and water-gas shift reactors while the remaining portion

will be sent to the DFC3000 as its cooling and water supply.

The water used to cool the DFC3000s will be split into two portions. Some will be sent through a

boiler/heat exchanger where it will be superheated to 300 °C to be fed to the gasification reactor. The

remaining portion of this water will be used to cool the DFC exhaust gas to 90 °C so that it can be safely

fed into the second membrane separator.

Any water condensed off by cooling the

DFC exhaust can be recycled in to the

cooling water loop to decrease total system

water consumption.

2.2 System Heat and Mass

Balances

All calculations were performed under the

optimal case where 0.00495 kg/s of

hydrogen will be saved and compressed

constantly for campus vehicular use. More

on this will be discussed in the End Uses

section.

Important values for total mass, heat, and electricity balance on the CHHP system can be seen in Table2.2. Table 2.3 contains the mass flow rates into and out of each important component of the CHHP cycle.

The residual mass out is evaporated water.

In Out

Straw 104 tonnes Ash 7.97 tonnesWater 164 tonnes Pyrolysis Vapor 29.8 tonnes

CO2 15.8 tonnes

CO 18.2 tonnesH2 428 kgElectricity 105,600 kW-hr

Heat 86,400 kW-hr

Table 2.2 Total System Balance Per Day



!

P a g e | 13

!

Table 2.3 Component Mass and Energy Balances

Reactor Heat Balance In (A) (kg/s) In (B) (kg/s) Out (A)

(kg/s)

Out (B)

(kg/s)

Temp ( ! C) Pressure

(bar)

Pyrolysis

Reactor

-1,084 kW 1.205 Straw 0.3843Biochar

0.8203Pyrovapor

500 1

GasificationReactor

-3,485 kW 0.3843Biochar

0.4803 Steam Syngas: 0.09222 Ash 700 1

0.05149 H2 0.7209 CO

Methanation

Reactor

646 kW Syngas: Permeate: SNG: 300 1

0.05149 H2 0.7209 CO

0.04071 H2 0.2906 CO0.2459 CH4 0.2766 H2O

Water Gas

Shift Reactor

326 kW SNG: SNG: 300 1

0.2906 CO0.2459 CH4 0.2766 H2O

0.02014 H2 8.718E-3 CO0.2459 CH4 0.09538 H2O0.443 CO2

CO2

Scrubber

SNG: Flash Cycle: SNG: FlashExhaust:

90 6

0.02014 H2 8.718E-3 CO0.2459 CH4 0.09538 H2O0.443 CO2

0.664 H2O 0.02014 H2 8.718E-3 CO0.2459 CH4 0.09538 H2O0.3765 CO2

0.06645 CO2

H2

Membrane

(1)

SNG: SNG: Permeate: 90 8

0.02014 H2

8.718E-3 CO0.2459 CH4

0.09538 H2O0.3765 CO2

2.014E-3 H2

8.718E-3 CO0.2459 CH4

0.09538 H2O0.3765 CO2

0.01812 H2

DFC Anode -1290 kW SNG: Added Water: Exhaust: 370 12.014E-3 H2

8.718E-3 CO0.2459 CH4

0.09538 H2O0.3765 CO2

0.4578 H2O 0.03059 H2 0.2109 CO0.8491 H2O

2.493 CO2

H2

Membrane

(2)

AnodeExhaust:

Exhaust: Permeate: 90 8

0.03059 H2 0.2109 CO0.8491 H2O

2.493 CO2

3.059E-3 H2 0.2109 CO0.8491 H2O

2.493 CO2

0.02754 H2

DFCCathode

MembraneExhaust:

Added Air To Anode: Exhaust: 90 1

3.059E-3 H2 0.2109 CO0.8491 H2O2.493 CO2

4.104 Air 2.3974 CO2 3.059E-3 H2 0.2109 CO0.8491 H2O0.0956 CO2

Residual N2

Hydrogen

Distributer

0.00495 H2 0.00495 H2 25 440

Cooling

Tower

0.9619 H2O 0.9619 H2O

Total -3,597 kW 2.1431 2.1426 0.024%Diff



!

P a g e | 14

!

2.3 Equipment Selection

Equipment was sized according to flowrates, temperatures, pressures, and reaction types. Table 2.4

contains all equipment specifications, vendors, pricings, and energy draws.xxiii

Table 2.4 Capital Costs: Equipment Manufacture, Pricings, and Energy DrawSystem Unit Supplier Unit Cost ($) Number of

Units

Installation($)

Power Draw

Straw Handling

Kubota M96SHDMTractor

Kubota Tractor Corp. 55,000 2 - -

Bale HandlingAttachment

Washburn Company 2,500 2 - -

Straw Intake

Hopper Beacon Technology 4,000 1 1,000 0

Chaff Cutter Custom 14,000 1 6,000 7.5 kW

Screw Conveyor Screw Conveyor Corporation 10,500 1 4,500 15 kW

Pyrolysis

Pyrolysis Reactor International Tech Corp 422,500 1 175,000 15 kW

Furnace International Tech Corp 195,000 1 105,000 -

Screw Conveyor Screw Conveyor Corporation 10,500 1 4,500 15 kW

Gasification

Reaction Chamber Zhengzhou Hongji Machinery

Manufacturing Co., Ltd.

24,000 1 16,000 7 kW

Furnace AESI Inc. 390,000 1 150,000 -

Methanation

Methanation Column Custom 24,000 4 128,000 -

Nickel Catalyst Liaoning Haitai Sci-Tech Development Co.,Ltd. 2,000/kg 150 kg - -

Feed Blower fromRecycle

New York Blower Company 45,000 1 4,000 25 kW

Feed Blower fromGasifier

New York Blower Company 67,000 1 6,000 30 kW

Heat Exchanger Industrial Heat Transfer Inc. 25,000 4 5,000 -

Water-Gas ShiftReactor

Packed Reactor Column

Custom 39,000 2 26,000 -

Cu/Zn/Al Catalyst Chempack 3/kg 5000 kg - -

Feed Blower New York Blower Company 17,500 1 4,000 22 kW


CO2 Scrubbing System

Gas Feed

Compressor

Ingersoll Rand 140,000 1 4,0000 350 kW


Packed ScrubbingTower

Custom 26,000 1 60,000 -

Scrubbing Water Pump

Gould Pumps 1,500 2 1000 2.5 kW

Water Chiller Thermax 16,000 1 4,000 20 kW



!

P a g e | 15

!

Flash Chamber Custom 9,000 1 4,500 -

H2 Handling

Membrane FeedCompressor

Ingersoll Rand 105,000 2 60,000 300 kW

Prism Membrane Air Products and Chemicals Inc. 20,000 2 10,000 -

High Pressure H2 Compressor

Hydro-Pac Inc. 63,000 1 27,000 50 kW

Storage Tank Dynetek 1,980,000 1 850,000 -

Vehicle FuelingDispenser

Kraus Global 90,000 2 20,000 -

DFC Fuel Cell Bank

DFC3000 FuelCell Energy 6,440,000 2 100,000 -5600kW

DFC Cathode Air Feed

Blower

Chicago Blower Corporation 21,000 1 7,000 25 kW

Boiler/HeatExchanger

Cleaver-Brooks 45000 1 15,000 -


Primary Cooling LoopPump

Gould Pumps 5,000 1 2,500 4 kW

Plant Power System - - 2231340 -

Local Grid IntegrationSystem

Avista Corporation 1,000,000 - - -

Plant Plumbing - - 1,301,615 -

Control Instrumentation - - 55,7835 -

TOTAL 18,594,500 5,936,790 -4409.5kW

2.3.1 Pyrolysis Reactor

A pyrolysis reactor with an asymmetric double screw is chosen to be used for pyrolysis of wheat straw.

An auger pyrolysis reactor capable of processing up to 8 tons/hr of feedstock is designed by Congen

Designs, Inc. The pyrolysis system comprises 4 parts: (1) Feeding auger with airlock; (2) Combustion gas

flow system; (3) Pyrolysis auger reactor; (4)

Combustion chamber with heat exchanger. Fig.

2.13xxiv

shows a basic pyrolysis reactor.

An auger pyrolysis unit capable of processing

up to 50 tons/day, is designed by International

Tech Corp. The system costs around $450,000.

2.3.2 Gasification Reactor

A fixed bed gasification reactor will be used for

the gasification of the wheat-straw char.

Although the most efficient gasification heat utilization is achieved by a heated fluidized bed reactor, this

system is slightly different. In most gasification reactors, part of the char or biomass is combusted to

Figure 2.13 Basic Pyrolysis Reactor



!

P a g e | 16

!

provide direct heat inside the reactor. Pyrolysis, gasification, and combustion occur in these reactors.

However, these reactors also create high concentrations of CO2 and have problems with tar build-up.

Therefore, we will utilize a fixed bed reactor.xxv

Heat Transfer to Gasification Reactor

In order to add heat for the endothermic water-gas reaction and to raise temperature to 700 ºC, the reactor

will be heated indirectly by combusting pyrolysis vapors. Heat will be transferred to the gasification

reactor from a furnace with horizontal radiant tubes (or rod cluster).

Ash Management

The mass of ash produced is 55.8 tonnes (97.8 m3) per week. The residual ash will need to be transported

to local landfills. The Pullman Disposal service offers industrial 40 yard dumpster drop box delivery and

return. A 40 yard dumpster holds 30.6 m3 of volume. The disposal service operates once per week, so we

will need 4 of these dumpsters. The cost of disposal is $99 per ton and $203.70 per dumpster. Therefore,

it will cost $342,000 per year to transport and dispose of the ash. This is a significant expense, but is

unavoidable, unless there are further uses for ash, as will be discussed in End Uses.xxvi

2.3.3 Methanation and WGS Reactors

Fixed bed reactors can be purchased from wholesale dealers. Catalysts can also be purchased from

wholesale dealers. Reactor sizes were chosen to optimize the amount of catalyst required for the desired

conversions.

2.3.4 Hydrogen Separation Membranes

Commercially available systems for separating hydrogen include Air Products’ Prism Separators. These

models were chosen due to their low maintenance requirements and efficiencies.

xxvii

2.3.5 DFCs

This system will use two DFC3000s sold by FuelCell Energy, Inc. Two units are used because of the

large quantity of wheat straw available. In fact, to utilize all of the wheat straw on the Palouse would

require about 12 DFC3000s. It was concluded, however, that it is not feasible to retrieve ALL of the

wheat straw available, so only two units will be used.

2.3.6 Hydrogen Compression

Hydrogen can be compressed to 450 bar by Hydro-Pac, Inc.’s C06-

40-5250LX pumps. Hydro-Pac also sells pump-compressor packages which come with high-pressure plumbing and electrical

controls. The energy required to compress the hydrogen to 450 bar

is 2.2 kW-hr/kg. Fig. 2.14xxviii

is a photo of this complex pump.xxix

2.3.7 Hydrogen Storage

The hydrogen needs to be stored in vessels that comply with ASMEFigure 2.14 High Compression

Pump



!

P a g e | 17

!

Division 3 High Pressure Vessel standards.xxx

A company called Dynetek makes such vessels. The DyneCells are designed to store a variety of

compressed gases at high pressure, including hydrogen, natural gas and various industrial gases. The

company can make customer-specified tank sizes. It would be wise to have 4 large tanks to allow for

cascading pressure drop.xxxi

Dynetek actually designs Hydrogen Stationary Storage systems featuring 3-stage cascade compression,

flexible configurations for roof or ground mounting, and total storage bank construction, including system

covers, vent stacks, piping, etc. It would certainly be wise to hire Dynetek to help design the hydrogen

storage facility

It is reasonable to have enough immediate storage for 5 days’ worth of hydrogen vehicle usage in case of

plant repair. One day of vehicular fuel hydrogen for the campus is 458 kg. Five days of hydrogen will be

2,290 kg. The estimated up-front cost of storage tanks is $1,323/kg hydrogen.xxxii

2.3.8 Hydrogen Dispensers

The hydrogen can be dispensed to buses or automobiles by an FTI fuel dispenser at 350 bar with a

maximum flow rate of 20 kg/min. Since Pullman, WA can have cold winters, the FTI fuel dispenser is

ideal since it can operate from -20 ºC to 60 ºC.xxxiii

2.3.9 Material Distributers

The straw and biochar will be transported by auger throughout the system. Liquids and gases will travel

through pipes. The plumbing system of the facility will be quite complex. Different piping sections

include transport of syngas, synthetic methane, hydrogen (high and low pressure), pyrolysis vapor, and

coolant water.

Voith Industrial Services can help plan out a safe and efficient plumbing system and plant organization.

Most piping will require stainless steel due to creep occurring at high temperatures. The high-pressure

hydrogen piping must satisfy ASME codes for high pressure gas flow.xxxiv

2.3.10 Electricity Integration

The electricity provider for the Pullman area is a company called Avista. Since the size of the theoretical

generator is larger than 300 kW, the production is too large to insert into the electric distribution lines that

run at 13 kV. It must be interconnected to the transmission grid for 115-2230 kV levels.

A good estimate for implementation to the grid would total about $1.5 Million, although Avista will still

own any equipment used for this connection. This means that maintenance on the equipment and

associated fees will be the responsibility of Avista, so our cost is only the one-time fee.xxxv

2.3.11 Heat Transfer Equipment

The heat exchangers for this system will be cross-current shell and tube type except for the steam boiler

on the DFC exhaust, which will be countercurrent to allow for the steam to be more efficiently

superheated after vaporization.



!

P a g e | 18

!

To drive the fluid flow, a pump will be placed adjacent to the cooling tower and another attached inline

ahead of the boiler to insure that sufficient pressure is maintained in this portion of the system. Both of

these pumps are available from Gould Pumps.

3 End Uses

There will be five usable products created at the CougsCARE CHHP facility: (1) H2, (2) Heat, (3) Power,

(4) Ash, and (5) Pyrolysis Vapor.

3.1 Hydrogen

The most novel part of this design is the production of usable hydrogen. This hydrogen should not simply

be vented out into the atmosphere. There are two major possibilities for using the hydrogen.

1. It can be compressed into transportation fuel to power the entire bus transit system, other campus

operation vehicles, and/or private vehicles.

2. It can be recycled back to the methanation reactor to create more methane for the fuel cell.

3. The hydrogen can be catalyzed at high pressure with nitrogen to produce anhydrous ammonia to sell as

fertilizer back to the farmers.

3.1.1 Transportation Fuel

An average Pullman Transit bus, like that in Fig. 3.1xxxvi, averages 3.68 mpg. With such a low fuel

economy, buses alone account for significant carbon emissions. Wouldn’t it be fantastic if they burned a

carbon-free fuel like hydrogen?

In some cities like Hartford, Connecticut, they already do. CTTRANSIT’s fuel cell bus achieved an

average fuel economy of 4.79 miles per kg. The fuel economy of the CTTRANSIT fuel cell bus equates

to 5.4 miles per diesel equivalent gallon, which is 47% higher than the diesel baseline bus average of 3.68

mpg.xxxvii

On an average day, all the running buses in Pullman combined travel about 1,250 miles, or 456,250 miles

per year. At 4.79 miles per kg hydrogen, they would need 95,251 kg hydrogen per year (assuming 365

Figure 3.1 Pullman Transit Bus



!

P a g e | 19

!

operating days to account for excess fuel usage). Since our system is estimated to create 1,600,000

kilograms hydrogen per year, our system will not only fuel the Pullman transit system, but have

excess.xxxviii

At $5.00/kg H2, Pullman transit can save $20,000 per year. This is not much money, but the CO2

emissions decrease significantly, as will be displayed in section 5.

Washington State University also has a fleet of over 700 vehicles. About half of these vehicles remain

constantly within a 150 mile radius, making it a possibility to replace them with hydrogen vehicles.

Approximately 2.5 million miles are driven per year by vehicles remaining close enough to refuel in

Pullman. Since the university would own the hydrogen, this would be equivalent to saving $315,000 per

year on gasoline, assuming an average gas price of $3.60 per gallon. This application would use

approximately 37,000 kg hydrogen.

The third possible use for excess hydrogen is to replace the University Motor Pool’s heavy equipment.

This includes backhoes, forklifts, front loaders, and other heavy machinery. They currently use 3 gallons

of diesel fuel every hour of operation, for 12,000 hours per year, which comes out to 36000 gallons per

year. Assuming that they could achieve an average of 2 kg of hydrogen per hour this would use another

24,000 kg of hydrogen saving the university $144,000 per year on diesel. Fig. 3.2 shows campus

vehicular fuel currently and after CHHP operation.xxxix

The total estimated campus vehicular use of hydrogen would be 156,251 kg/year (428 kg/day) and save

the school $3,650,002.

495,924 476,253144,000 0

314,685

0

5,839,000

3,269,000

6,793,609

3,745,253

Current System With CHHP

S p e n d i n g

( $ / y e a r )

Diesel,bus Diesel,heavy equipment Gasoline,cars Natural Gas Total

Figure 3.2 Current and Proposed Energy Expenses at WSU



!

P a g e | 20

!

3.1.2 Recycling Hydrogen to Methanator

Even if it is not possible for the school or anyone to purchase any fuel cell vehicles, the separated

hydrogen can always be recycled back into the system to create electricity. This decreases the straw feed

rate when using the same number of DFC systems.

3.1.3 Fertilizer Production

As an agricultural region, the Palouse farms require a huge amount of fertilizer to keep the crops growing

at high rates. In fact, nitrogenous fertilizers are considered to be the single most important invention in

the history of mankind.xl

One of the most common forms of fertilizer is ammonium nitrate (NH4 NO3), which is produced from

ammonia and nitric acid. This famous reaction is known as the Haber process. Producing the ammonia

and nitric acid is usually created by gasifying natural gas and combining that hydrogen with nitrogen from

the air. Using natural gas, the energy requirement is 31.97 MJ/kg NH3. Creating nitrogenous fertilizer

from NG is actually considered one of the single largest energy draws in the world.xli

Instead of using natural gas, a fossil fuel, our system creates hydrogen from wheat straw, creating a

product from the Palouse, for the Palouse. Since this process starts with hydrogen gas instead of

methane, there is actually a release of heat in the overall cycle.

Future work would need to be done to design an entire ammonium nitrate production facility, but it is a

well-known process with huge potential for an addition to the CougsCARE facility.

3.1.4 Additional Hydrogen End Uses

Washington State University has a very robust research facility for studying hydrogen gas, known as the

HYPER Laboratory, run by Dr. Jacob Leachman. This lab will certainly appreciate a constant supply of hydrogen right on campus.

3.1.5 Available Diversification

As the market for hydrogen changes, it might be more profitable to sell more hydrogen gas as

transportation fuel or even use all of it to produce electricity.

There is so much research being done on hydrogen currently that there may be even more feasible uses in

the future. When those uses become available, CougsCARE will be ready to supply the amazing element. !

3.2 Heat

The massive heat output of approximately 3.5 MW can be used to heat the greenhouses on campus. This

heat can be sent to greenhouses across the street, where produce can be grown all year round, and sold for

further profit. Fig. 3.3 shows a map of the greenhouses directly across the road (Grimes Way).



!

P a g e | 21

!

!

Figure 3.3 Map Showing Greenhouses Across the Road

3.3 Power

WSU consumes 162,352,083 kW-hr per year. The average power draw is 18.5 MW. The CougsCARE

plant will generate 4.4 MW continuously, 347 days per year (allowing for maintenance periods). Though

most power in Washington comes from hydro-electric plants or nuclear energy, it would certainly be

beneficial to cut down on their energy bill. Power usage on the WSU campus can be seen in the

Appendix.

Furthermore, if the school buys energy from CougsCARE, the money ultimately goes to the farmers, who

are paid for their feedstock.

3.4 Ash

The ash does not need to go to waste. Since it is highly basic, most farmers cannot add it to their fields.

There are a few potential options other than sending it all to a landfill.

1. Researchers are currently studying the use of ash as an absorbent to separate CO 2 out of gas streams.

This would create bicarbonate, a highly useful chemical.

2. Ash could be used by biologists on campus to reduce CO2 emissions from their anaerobic digestion

equipment.



!

P a g e | 22

!

3. Since the ash is slightly alkali, some farmers might want to use it to adjust the pH of their soil since

nitrogen-based fertilizer can lower the pH of the soil. These farmers will be allowed to take as much ash

as they would like.

Until more research is completed, the ash can be transported to landfills.

3.5 Pyrolysis Vapor

CougsCARE will send 12.3 million kg of pyrolysis vapor to the steam plant per year. This will save the

steam plant $1.43 million per year at the current natural gas price. It will also save it 16,119 tons of fossil

fuel CO2 emission per year.

4 Safety Analysis

4.1 Classification of Dangers

The most significant safety risk of this system would be from explosion of pyrolysis vapor and hydrogen.Both of these gases are flammable and could explode under the right conditions, which could cause

significant damage to the power plant as well as loss of life. The causes of dangerous events can be

described by these categories; mechanical or material failure, corrosion attack, over-pressurization,

rupture due to impact by shock waves and missiles from adjacent explosions, and human error.

Because of this, equipment should be tested periodically to ensure that materials have not undergone too

much corrosion and mechanical systems are working as expected. Pressure gauges should also be used at

specific points in the system to notify operators of any unexpected discrepancy with the desired pressure.

The system should be installed far from any other possible explosions, and all checks and tests should be

performed by more than one person to avoid human error.

Barricades could also be designed to protect against explosions. Many possible dangers have been

identified and codes and laws have been created.xlii

The codes and standards in Table 4.1 in the appendix should all be met by the system prior to operation.

4.2 Plant Location

Fortunately, the plant location is in a very safe area. The steam plant was intentionally built in a location

such that there are large hills between the plant and residential dormitories and classrooms. Since the

hydrogen production facility will be built adjacent to the steam plant, any explosion in the facility will be

naturally blocked from high-density population areas.

4.3 System Monitoring and Process Control Instrumentation

Various temperatures and pressures are encountered throughout our thermochemical conversion

processes.



!

P a g e | 23

!

Implementation of a comprehensive monitoring system will be necessary to ensure that the plant is

operating under safe conditions and to prevent major failure. It is extremely important to monitor and

control the continuous process from one location. Therefore, a control system must be purchased.

Siemens is a leading manufacturer of process control systems. The best model for this continuous flow

system is the SIMATIC PCS 7. This system can receive flow, temperature, and pressure values andexchange control commands throughout the system. Units that must be closely controlled are the

compressors, blowers, pumps, furnaces, and cooling loops.xliii

While Siemens produces the process control system, sensors are still required. Things to monitor are

leakage, temperature distribution, and pipe corrosion. Roctest Group produces monitoring systems and

sensors that can be integrated with the SIMATIC PCS 7.xliv

5 Economic Analysis

Washington State University is the ideal location for this energy conversion system since it is located in

the heart of the bountiful Palouse region. By locating this plant in such an area, the cost of acquiring thewheat straw feedstock to run this system is kept low while allowing the local area to reap in the benefits

of clean, renewable energy.

This analysis covers the cost of purchase and installation of all major system components as well as

additional consideration for extra costs included in building such a facility such as electrical wiring,

plumbing, yard improvements, and process control units. This data is shown in Table 2.4 on page 14. The

large amount of open land on the WSU campus is yet another reason the Pullman, WA location is ideal as

it allows for the affordable storage of the large amounts of wheat straw needed for continual system

operation throughout the year. For some of the larger reactor units, correlations from plant design texts

were used to estimate the overall costs as no such units are produced without precise custom designs.

Based on the equipment and installation costs, the capital investment will be $24,531,290.

The maintenance and labor costs were based on Timmerhaus values for the approximate time periods of

service that should be expected from such unit operations as are involved in this system, including

catalyst renewal costs and periodic unit renovations. The large initial investment cost can be defrayed

with government supported Clean Renewable Energy Bonds (CREBs) that serve to encourage the

building of renewable energy plants by providing tax credits to the holder in lieu of interest payments

from the issuing party.xlv

Operational costs for the system are limited almost entirely to feed straw, labor, and disposal of the ash

waste product produced by the gasification step. The magnitude of this system allows the production of

substantial enough amounts of hydrogen to eventually turn a profit as the market for hydrogen develops

around this system. While the cost of producing this electricity, $ 0.143/kW-hr, is higher than the current

utility rates of $ 0.062 /kW-hr, it will help to offset the cost of operating the system while the local

markets develop to utilize this new hydrogen resource. Annual itemized costs for this system were shown

in Table 5.1, which includes the production of both hydrogen and electricity and the estimated cost to

produce each.xlvi

xlvii

Without a doubt, the largest hindrance to the implementation of this system is the vast capital that is

required to purchase such a system, as seen in Table 2.4. However, as hydrogen producing power plants



!

P a g e | 24

!

such as this system are implemented, the practicality for the average commuter to begin driving hydrogen

fueled cars greatly increases as more hydrogen fueling stations become available. With the presence of

more hydrogen vehicles on the road, a greater portion of the produced hydrogen can be used for retail sale

and not power production. At the current cost of $4.32/kg H2, this plant design has the potential to be a

competitive producer of hydrogen for future markets, considering that hydrogen fuel sells for over $8 a

kilogram in areas such as Washington D.C.xlviii xlix

At the present electricity, fuel, and natural gas rates this system will not immediately turn a profit,

however there are currently many proposed carbon taxes being considered that could drastically change

the profitability of this system. In Table 5.2 the energy costs incurred by Washington State University on

an annual basis are estimated for 2012 both with and without the CHHP system. This table also includes

an estimated cost analysis to the campus for 2020, assuming energy prices continue to follow trends

similar to the last decade and a carbon tax is implemented that is approximately equal to the average of

the various currently proposed carbon taxes in the U.S. in 2020. This results in a substantial economic

benefit to system implementation in 2020. l

The estimated market value for the plant is $33,494,290 based on Timmerhaus engineering economicscorrelations.

li

Table 5.1 Annual Product Cost Analysis

Cost ($)

Total Cost for Straw 2,167,200 Hydrogen Produced Annually 1,369,000 kg

Labor 605,000 Hydrogen Consumed for Electrical

Generation

1,220,000 kg

Ash Disposal 342,000 Gross Energy Production 46,636,000 kW-hr/year

General Maintenance 950,000 Parasitic Energy Load 9,914,484 kW-hr/year DFC Maintenance 1,400,000 Net Energy Production 36,722,000 kW-hr/year

Service Vehicle Fuel Costs,

$4.00/gal

96,000 Hydrogen Unit Cost $ 4.32 /kg

Total Operational Costs 5,560,200 Electricity Unit Cost $ 0.435 /kW-hr



!

P a g e | 25

!

Table 5.2 Annual Energy Costs and Consumptions

2012

Without CHHP

2012

With CHHP

2020

Without CHHP

2020

With CHHP

Electricity Usage from Avista 162,352,083 kW-

hr/year

125,630,000 kW-hr/year 162,352,083 kW-

hr/year

125,630,000 kW-hr/year

Estimated Unit Cost ($) 0.062/kW-hr 0.062/kW-hr 0.08/kW-hr 0.08/kW-hr

Electricity Cost ($) 10,065,000 7,789,000 12,988,000 10,050,000

Natural Gas for Steam

Production

20,410,000

kg/year

15,400,000 kg/year 20,410,000

kg/year

15,400,000 kg/year

Cost, 0.286/kg (11 year average)

($)

5,837,000 4,404,000 5,837,000 4,404,000

Fueling Cost for Campus

Vehicles ($)

833,000 372,000 1,457,000 651,000

Estimated CO2 Carbon Tax

Rate ($)

0 /ton 0 /ton 53.43 /ton 53.43 /ton

Avoided CO2 Emissions 0 tons/year 54,000 tons/years 0 tons/years 54,000 tons/years

Avoided Carbon Tax ($) - - - 2,885,220

CHHP System Operating Cost($)

- 5,560,200 - 5,850,000

Total Energy Costs ($) 16,735,000 18,125,200 20,282,000 18,069,780

Net Savings with CHHP System

($)

(1,390,200) 2,212,220

Table 5.3 CHHP System Market Value

Cost ($)

Purchased Equipment Cost 18,594,500

Purchased Equipment Installation 5,936,790

Estimated Land Cost 1,500,000Engineering and Construction 3,850,000

Contractor's Fee 13,000

System Training and Contingency 3,600,000

Estimated Marketing Value 33,494,290

6 Environmental Analysis

According to the equations and constants given in the specifications for environmental analysis this

system’s total avoided CO2 emissions comes out to 54,063 tons per year. The total avoided fuel is 685,292million Btu per year. The origin of these totals can be seen in Table 6.1. Calculations of values can be

seen the Appendix. Fig. 6.1 shows CO2 emissions avoided if WSU replaces campus vehicles with fuel

cell vehicles.



!

P a g e | 26

!

Table 6.1 Fuel and Emissions Savings

Origin Avoided Fuel (MMBtu/ year) Avoided CO2 Emission (tons/ year)

Central Station 379,318 35,598

Bus Replacement 16,453 1,273

Car Replacement 10,927 846

Heavy Machinery 4,284 332

Thermal 276,009 16,119

Total 685,292 54,063

!

7 Education & Marketing

It is extremely important for the local community to understand the positive impact of CougsCARE. If

we want to convince the farmers to sell us their straw, we need to make sure that they understand what

will be involved in the process, how they can sign up, and how much they will get paid. It is equally

important to convince the school administration, Pullman city council, and local residents that this project

is feasible, safe, and desirable.

##$! %&'! $($&"!

$)($$*!

#'('*%!

'&(+#)!

+!

$+(+++!

"+(+++!

#+(+++!

&+(+++!

'+(+++!

)+(+++!

,-./0!

123456-78!

9.:;! <3;! =>-:6.?! 9-78:[email protected]! =B8.?!

! "

# $ $ # % & $ ( ) % # * + * , - % & $ . / + 0 1 2

Figure 6.1 Avoided CO2 Emissions Breakdown



!

P a g e | 27

!

The Business and Marketing department at WSU can help manage the public education and awareness

plan. First, they will develop questionnaires to compile response data and recommend the next best steps

for marketing the project.

7.1 Education

Town meetings, mail brochures, website and email questionnaires, and telephone interviews will be used

to collect response data. Each issue will be addressed appropriately. For example, if a significant portion

of data suggests there is not enough awareness about hydrogen safety, we will stage a meeting to talk

specifically about hydrogen safety. Meetings will be podcast and published in text format on the website

to make sure those farmers who do not live in Pullman can reach the information.

Other forms of education will include billboards, pamphlets for handing out at farmers association

meetings, pamphlets for Pullman residents, press releases, a grand opening fair, public meetings, and

classroom lectures on the WSU campus.

One major part of disseminating the ideas is having a robust website. The website will not just be for marketing the information to the public, but for organizing the straw delivery network. On the website,

farmers can pledge straw to the hydrogen facility each year and get paid through the website upon

delivery. Each farmer will be able to create their own account on the website.

7.2 Marketing

It is important to have catchy slogans and memorable names. The focus of the project is beyond making a

profit. It is truly about using the natural, local resources to bring fuel money to farmers and improve the

quality of the environment. This production plan will seriously cut down on CO2 emissions and the

farmers will get paid for straw, a previously useless field residue.

“Clean Air Today, Cleaner Air Tomorrow” is a memorable slogan, and “CashForStraw.com” would be a

catchy domain name. Both of these phrases appear on a pamphlet/billboard that will be used to market

the plan, as can be seen in Fig. 7.1.



!

P a g e | 28

!

Figure 7.1 Marketing Poster



!

P a g e | 29

!

Appendix

Anode Outlet Gas (AOG) Composition calculation

2.19 DFC Reformer and Anode

Assume all the methane entering the DFC system is converted to hydrogen. The reactions at the anode

are:

CH4 + 2H2O! 4H2 + CO2 (1)

H2+ CO3- ! H2O + CO2 (2)

Also assume 1 mole of CH4 is input to the DFC system. 65% of the H2 produced in equation (1) is

consumed at the anode.

2.6H2+ 2.6CO3- ! 2.6H2O + 2.6CO2 (3)

The remaining 35% of the H2 and all of the CO2 from equation (1) goes directly to the AOG.

1.4H2 + CO2 (4)

Combining the products from (3) and (4) yields

1.4H2 + 2.6H2O + 3.6CO2 (5)

In reality the actual internal reforming reaction has two steps:

CH4 + H2O! 3H2 + CO (6)

CO + H2O! CO2 + H2 (7)

Furthermore, not all the CO is shifted to hydrogen, as we assumed in step one above. In order to account

for this fact, we assume that there is approximately a 2:1 ratio of hydrogen to carbon monoxide in the

anode gas. In order to accurately calculate the AOG composition for the DFC system we need to back-

shift 1/3 of the H2 (in equation 5) to CO using equation 7.

This yields –

0.47H2 + 0.47CO2 ! 0.47H2O + 0.47CO (8)

Combining (5) and (8) yields the following products –

0.93H2 + 3.07H20 + 0.47CO + 3.13CO2 (9)

Molar flow-rates from equation 9 are added to the components in the incoming stream that do not react at

the anode surface.lii



!

P a g e | 33

!

6.5 Determine Total Fuel and CO2 Savings

!!!"!"# ! !!!"#$%&' ! !!!!!"#$% ! !!!"##$%&'(%&)*+ ! !!!"#$%&'#()*%!!"#$% ! !"!!"#$%

! !!"#$%&! !"#$$% ! !"#$" ! !"#$% ! !"#! ! !"#!##!!"#$

!"#$

!"#!!"#$% ! !"#!!"#$%&' ! !"#!!!!"#$% ! !!"!!"##$%&'(%&)*+ ! !"#!!"#$%&'#()*%!!"#$%

! !"#!!"#$%&'()*+",- ! !!"#! !"!!#! !!"#! !"#!! ! !!"!! ! !"#$%!"#$

!"#$

6.6 Determine Amount of Organic Waste Avoided

!"#$%&%!!"#$% ! !"#$%&'!!"#$%!!"#$%& ! !"#$%!!"#$%!!"#$%!& ! !"#"$! !"#$ ! !"#$%!"#$

!"#$

Fuel and Electricity Consumption at WSUliii

The Pullman campus used the energy noted below in fiscal year 2011 (July 2010 thru June 2011):

162,352,083 kWh of electricity at a cost of $10,052,745.

9,761,170 therms of natural gas at a cost of $5,205,000. (steam generation)

91,153 gallons of diesel fuel at a cost of $191,159. (steam generation)

The monthly breakdowns are:

Electricity Nat. Gas Diesel

(kWh) (Therms) (Gal) July 2010 13,864,563 370,010 2,215

August 2010 14,368,728 341,000 1,138

September 2010 13,435,272 520,050 1,886

October 2010 13,610,451 675,500 4,116

November 2010 13,534,302 1,023,000 7,450

December 2010 14,329,211 1,311,000 12,883

January 2011 14,186,866 1,247,000 17,320

February 2011 13,331,574 1,082,000 19,634March 2011 13,732,302 1,015,000 18,373

April 2011 13,159,780 901,610 3,778

May 2011 12,506,619 755,000 740

June 2011 12,292,415 520,000 1,620

Total: 162,352,083 9,761,170 91,153



!

P a g e | 34

!

References

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!iWashington Wheat Commission, (2009). Washington wheat facts 2008-2009.

Retrieved from WWC website:

http://admin.aghost.net/images/E0177801/2008WF4WebSmHomepage.pdf ii

1 tonne=1000 kgiii

Frear, C., Zhao, B., Fu, G., Richardson, M., & Chen, S. Washington State Dept. of Ecology, (2005).

Biomass inventory and bioenergy assessment (05-07-047). Olympia, WA: Dept. of Ecologyiv

Bair, G., & Bair, K. (wheat farmers) (2012, Jan 05). Interview by J Bair [Personal Interview]. Wheatstraw pricing.

v Google.com/mapsvi

"Thermal Pre-Treatment of Biomass for Large-Scale Applications ." IEA Bioenergy. International

Energy Agency, n.d. Web. 30 Jan 2012. <http://ieabioenergy.com/DocSet.aspx?id=6735>vii

Klass, D.L., 1998. Biomass for Renewable Energy, Fuels and Chemicals. 1st Edn., Academic Press,San Diego, CA., ISBN: 10: 0124109500.

viiiFjellerup, Jan. "Pyrolysis and Combustion of Pulverized Wheat Straw in a Pressurized Entrained Flow

Reactor." . Department of Combustion Research, 21 May 1996. Web. 30 Mar 2012.<http://pubs.acs.org/doi/abs/10.1021/ef950204e>

ixKristen Dechert. SERC Auger Reactor Design. 2011. Photograph. Mississippi State UniversityWeb. 2

Feb 2012. <http://www.serc.msstate.edu/news.html>.x Gupta, Ram. Hydrogen Fuel: Production, Transport, and Storage. 1. Boca Raton, Florida: CRC Press,

2009. 191. Print.xi

Chaudhari, S.T. "Production of Hydrogen and/or Syngas (H2 CO) via Steam Gasification of Biomass-Derived Chars." Energy and Fuels. 17. (2003): 1062-67. Print.

xii"Specifications for CHHP System Design." Hydrogen Education Foundation. Hydrogen Education

Foundation, n.d. Web. 30 Jan 2012. <http://hydrogencontest.org/pdf/CHHP Design Basis FCE Nov

2011.pdf>.xiii

"Methanation." . ECN, 06 May 2007. Web. 20 Jan 2012. <http://www.biosng.com/experimental-line-

up/methanation/>xiv Kopyscinski, Jan, Tilman Schildhauer, and Serge Biollaz. "Production of synthetic natural gas (SNG)

from coal and dry biomass – A technology review from 1950 to 2009." Fuel . 89.8 (2010): 1763-83.

Printxv

"Methanation." . ECN, 06 May 2007. Web. 20 Jan 2012. <http://www.biosng.com/experimental-line-up/methanation/>.

xviPRO/II is a process simulation software program made by Invensys, Inc.

xvii "Gasification Systems: Gas Separation." The Energy Lab. DOE, n.d. Web. 1 Feb 2012.

<http://www.netl.doe.gov/technologies/coalpower/gasification/gas-sep/index.html>.xviii

Cai, Yeping. "Low Temperature Water Gas Shift Reaction over Cu/Zn/Al Catalysts." . Süd Chemie

Inc., n.d. Web. 22 Feb 2012. <http://www.nacatsoc.org/18nam/Posters/P092-Low Temperature

Water Gas Shift Reaction.pdf>.

xix Kapdi, S.S., V.K. Vijay, S.K. Rajesh, and Prasad Rajendra. "Biogas scrubbing, compression andstorage: perspective and prospectus in Indian context." Renewable Energy. 30. (2005): 1195-1202.

Web. 31 Mar. 2012.xx

Fcell_diagram_molten_carbonate. 2011. Photograph. WikimediaWeb. 2 Feb 2012.<http://upload.wikimedia.org/wikipedia/commons/0/0b/Fcell_diagram_molten_carbonate.gif>.

xxi Wierzba, I. "Flammability limits of hydrogen–carbon monoxide mixtures at moderately elevated

temperatures." International Journal of Hydrogen Energy. 26.7 (2001): 649-53. Web. 31 Mar. 2012.<http://www.sciencedirect.com/science/article/pii/S0360319900001142>.



!

P a g e | 35

!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!xxii Gardiner, Monterey. "DOE Hydrogen and Fuel Cells Program Record." . DOE, Web. 22 Jan 2012.

<http://www.hydrogen.energy.gov/pdfs/9013_energy_requirements_for_hydrogen_gas_compression.pdf>

xxiiiPeters, Max, and Klaus Timmerhaus. Plant Design and Economics for Chemical Engineers. 4th. San

Fransisco: McGraw-Hill Inc., 1991. Print.xxiv Jones, Fred. "BIOMASS PYROLYSIS." Bioenergy Conference. 2008. Oakland, CA: Oakland

University, 2008. Print.

<http://www.oakland.edu/upload/docs/Energy/BioEnergy_Conf/08_Fred_Jones_Pyrolysis.pdf>.xxv

Brown, Robert. Biorenewable Resources: Engineering New Products from Agriculture. 1st ed. 2003.

148.xxvi "Washington Trash Rates." . WUTC, Web. 10 Mar 2012.

<http://www.pullmandisposal.com/garbage.htm>.xxvii

"Advanced Prism Membrane Systems for Cost Effective Gas Separations." Air Products. AirProducts,

n.d. Web. 30 Jan 2012xxviii

LX Series Gas Compressor . 2011. Photograph. Hydro-Pac, Fairview, PA. Web. 3 Mar 2012.<http://www.hydropac.com/HTML/photo.html>.

xxix Gardiner, Monterey. "DOE Hydrogen and Fuel Cells Program Record." . DOE, Web. 22 Jan 2012.

<http://www.hydrogen.energy.gov/pdfs/9013_energy_requirements_for_hydrogen_gas_compression.pdf>

xxx"Pressure Vessels Division 1." ASME.org . ASME, Web. 30 Jan 2012.

<http://www.asme.org/kb/standards/bpvc-resources/boiler-and-pressure-vessel-code---2010-

edition/viii--pressure-vessels---division-1>xxxi

"Hydrogen Tank Specifications." Dynecell . Dynetek,Web. 05 Jan 2012.

<http://www.dynetek.com/pdf/450_Bar_Specifications.pdf>.xxxii

Amos, Wade. "Costs of Storing and Transporting Hydrogen." . National Renewable EnergyLaboratory, Nov 1998. Web. 30 Mar 2012.<http://www.madrimasd.org/queesmadrimasd/Pricit/PlanNet/documentos/03/documentos/publico/T

DAUF/Hidrogeno/storage_1998.pdf>.xxxiii

"Hydrogen Dispensers: Safe Hydrogen Refueling." Fueling Tech. FTI, Web. 14 Mar 2012.<http://www.fuelingtech.com/index990e.html?id=806>.

xxxiv"Be on the Safe Side." Voith Industrial Services. Voith, Web. 15 Mar 2012.<http://www.voithindustrialservices.com/en-petro-chemical.htm>.

xxxvKnutson, Dan. Senior Engineer, Avista Utilities. Telephone Interview. 20 Mar 2012.

xxxvi2011. Photograph. Pullman Transit, Pullman. Web. 15 Mar 2012.

<http://www.parking.wsu.edu/File/transit_new_lg.jpg>.xxxvii

"National Renewable Energy Laboratory." Web. 12 Mar 2012.<http://www.nrel.gov/hydrogen/pdfs/47334-1.pdf, http://fuelcell.cttransit.com/>.

xxxviiiThorton, Rod: Pullman Transit. Telephone Interview. 14 Mar 2012.

xxxixRevetto, Dennis. Personal Interview. 10 Mar 2012.

xlTownsend, Alan, and Robert Howarth. "Fixing the Global Nitrogen Problem." Scientific American. 27

Jan 2010: n. page. Web. 12 Feb.. 2012. <http://www.scientificamerican.com/article.cfm?id=fixing-the-global-nitrogen-problem>.

xli "Energy Conservation in Corn Nitrogen Fertilization." Farm Energy. Iowa State University, 01 Sep

2010. Web. 1 Apr 2012. <http://www.extension.iastate.edu/Publications/PM2089i.pdf>.xlii

Gupta, Ram. Hydrogen Fuel: Production, Transport, and Storage. 1. Boca Raton, Florida: CRC Press,2009. 537-66. Print.

xliii"Innovative SIMATIC PCS 7 process control system."Chemical Industries. Siemens, n.d. Web. 10

Mar 2012. <http://www.industry.siemens.com/verticals/global/en/chemical-industries/chemical-

industries-products-systems/process-control-system/simatic-pcs7/Pages/Default.aspx>



!

P a g e | 36

!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!xliv "Chemical Plant Monitering Systems." Roctest Smartech Telemac. Roctest Smartech Telemac, Web.

12 Mar 2012. <http://www.roctest-group.com/applications/chemical>.xlv

"National Renewable Energy Laboratory." Web. 12 Mar 2012.

<http://www.nrel.gov/hydrogen/pdfs/47334-1.pdf, http://fuelcell.cttransit.com/>.xlvi

Peters, Max, and Klaus Timmerhaus. Plant Design and Economics for Chemical Engineers. 4th. SanFransisco: McGraw-Hill Inc., 1991. Print.xlvii

"FEDERAL Incentives/Policies for Renewables & Efficiency." Renewable Electricity Production Tax

Credit (PTC) (2011): n.pag. DSIRE . Web. 31 Mar 2012.<http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=US13F>.

xlviiiHealey, James. "Test Drive: Fuel-cell Clarity has tantalizing future." USA Today 05 Sep 2008, n. pag.Print. <http://www.usatoday.com/money/autos/reviews/healey/2008-09-04-honda-fcx-

clarity_N.htm>.xlix

"Today’s Hydrogen Production Industry." DOE . DOE, n.d. Web. 02 Mar 2012.

<http://www.fossil.energy.gov/programs/fuels/hydrogen/currenttechnology.html>.l"Are EPA Hammers The Best Tools to Ratchet Down Global Warming Pollution?." Carbon Tax Center .

Carbon Tax Center, 2012. Web. 1 Apr 2012. <http://www.carbontax.org/>.li Peters, Max, and Klaus Timmerhaus. Plant Design and Economics for Chemical Engineers. 4th. San

Fransisco: McGraw-Hill Inc., 1991. Print.lii

"Specifications for CHHP System Design." Hydrogen Education Foundation. Hydrogen Education

Foundation, n.d. Web. 30 Jan 2012. <http://hydrogencontest.org/pdf/CHHP Design Basis FCE Nov2011.pdf>

?444!Ryan, Terry. Director of Energy Services at WSU. Email interview. 10 Mar 2012.!

washington state university-chhp system design

Documents