The Cellulosic Ethanol

Group

Group Members: David Irvin Jeff Bennett

Vaughn Moser

Table of Contents:

Section 1: Introduction

Page: 2: Acknowledgements

3: Introduction

4: Abstract

5: Literature Review

7: Solution

Section 2: Design Process

Page: 9: Design Process

11: Design Challenges

13: Analysis/Experimental Work

14: Specifications

16: Drawings

Section 3: Implementation

Page: 23: Construction

26: Testing/Evaluation

Section 4: Project Management

Page: 28: Budget

Section 5: Conclusions

Page: 29: Conclusions

Section 6: Future Work

32: Future Work

Section 7: Appendices

Page: 33: Appendices

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Acknowledements:

We would like to acknowledge all of the following:

For technical and practical advice concerning agricultural practices:

Mike Berkheimer

Lyndon Moser

For completing a nutritional analysis of our corn stover:

Dick Matthews

For donating gifts in kind and lending of equipment:

Detail Consulting Inc.

For technical assistance and use of facilities

Prof. Oberholser

Prof. Erikson

Use of tools:

Messiah engineering shop (John Meyers)

All group members

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Introduction:

Corn stover is the leaves, stalks, and cob left over from a corn plant after the

kernels have been harvested. Corn stover is currently not being used, and for the most

part simply left in the field to decompose. According to the “Corn Stover Collection

Project,” it is the largest quantity of biomass residue (220 million tons) in the United

States providing the potential to supply around 6-14 billion gallons of ethanol. The

production of cellulosic ethanol from corn stover is just entering the commercially

feasible stage with the limiting factor being the efficiency of the conversion of the

cellulose and hemi-cellulose to glucose. Typically measured by the cost of the enzyme

per gallon of the ethanol produced, the cost of the enzyme has dropped dramatically to

between 10-18 cents/gallon (Patel-Predd 4052) on the large scale.

We built a small scale system that allowed us to attempt to produce ethanol from

corn stover available in the area. The components of the system were relatively cheap

and the system was functional. We were able to produce glucose from cellulose and

hemi-cellulose in small quantities. However, we were not able to able to convert this

glucose to ethanol due to issues with our fermentation process. We are still not sure if it

was the yeast used, the temperature the system was held at, or the time we allowed for

fermentation. We experimented with both mechanical pretreatment options and chemical

pretreatments. Overall, we feel we overcame the hardest part of the process in that we

were able to convert the cellulose to glucose and feel any future work done on this project

would be able to complete the process, improve the repeatability and efficiency of the

system, and make a better estimate of the economy of the system

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Abstract:

Corn Stover is one of the largest untapped natural resources in the United States

and is both renewable and more environmentally friendly than fossil fuels. We

attempted to harvest this resource with a small scale system of production capable of

converting it to ethanol. We were able to build a functioning system of production

relatively cheaply and showed that it is feasible to produce ethanol from corn stover using

our system. However we were not actually able to produce any but were able to

determine it would not be economical with our system to hope for any kind of profit on

such a small scale. Future teams would most likely be able to complete the process and

greatly improve the efficiency of the process through testing of different enzymes,

pretreatments, and ratios of enzyme to solid, etc.

Objectives:

1. Identify/procure necessary additives for a functional cellulose based ethanol plant.

2. Build an ethanol plant capable of producing one gallon of ethanol per batch.

3. Replicate the process and achieve a constant 190 proof product.

4. Identify and analyze the cost of the process and plant to see if an economic gain is

possible

5. Produce 10 gallons of ethanol by May 2007.

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Literature Review:

Based on research done online through the websites of many government

agencies, scholarly journals, and commercial companies, we found that production of

ethanol from corn stover is a beneficial process that has been accomplished by several

research corporations, including Iogen. Iogen has actually built a large scale production

prototype plant to show the feasibility and profitability of ethanol from corn stover and

switchgrass. We were able to read a book given to us by our advisor, Mr. Erickson,

called the “Applied Energy Technology Series” which had a section on the production of

ethanol. However, relative new advances in technology are more likely to be found in

magazines and government websites and scientific journals. Thus far, our literature has

consisted of information from the National Renewable Energy Laboratory (NREL)

website, Popular Mechanics on the profitability margin, the Celunol Corporation website

(a corporation that produced and patented metabolically engineered strains of

microorganisms used in the production of ethanol), Department of Energy (DOE)

website, information from Purdue University as well as Iowa State, The Harvest Clean

Energy organization, and lastly, the organization Journey To Forever. While not all these

resources are scholarly, useful information can be gleaned from them that can help lead

to other resources that are scholarly.

What we found is that large corporations and universities have done research and

determined that it is both physically possible and even commercially feasible using an

integrated approach of the newest technology that utilizes all by-products. Our project

incorporated the latest breakthroughs in enzymatic technology we were able to procure.

However we were limited by time and the availability of some of the products, especially

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the required enzyme, which was not as effective as we were lead to believe it would be.

Because of the limited time and budget constraints, we were not able to develop a

continuous batch operation that produces ethanol. This could be easily accomplished in

the future, because it only requires building two more identical systems. Because of the

similarity of these systems, we are using only one for this year. Once we had settled on a

design for our system, the majority of our time and energy went into building the system

and we were able to get all pertinent information from conversations with faculty and

various professionals.

Solution:

Early on, we did a great deal of research to determine the best available processes

for producing ethanol from corn stover. We determined enzymatic hydrolysis process to

be the cutting edge process of the future and also possible to be completed within our

limited resources. We were able to get most of the necessary components from local

stores within our budget except for our temperature control device which though

expensive was donated and less expensive components could have been utilized. The

cellulase enzyme used also needed to be ordered and was procured from Novezyme

whom along with IOGEN is one of the leading companies in cellulosic ethanol. It is

possible in future years that there will be other technological leaders in the field of

enzymatic hydrolysis and this should be researched by future groups. Other components

were also donated, such as the barrels, but could have been acquired for minimal cost.

The actual design of the system itself basically remained unchanged throughout

the year. However, certain specifications, such as the pump type and the size of tubing

used were experimented with and the heating element was improved on over original

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specs. Different information, such as the temperature at which the slurry should be

maintained for each stage, also changed during testing as we strove to make the system

more efficient and the length of time we ran each stage varied also in an attempt to

increase production.

The actual system was began in early February and completed in March after

which testing of the system began. Prior to any actual test runs with our system, small

scale testing was done to determined different ratios of water, enzyme, and stover.

Different testing was done on our system to test each process of the system. The

performance of the system was determined by measuring the change of glucose present

within the slurry.

The most technically demanding portion of our project was to perfect the

chemical reaction which converts cellulose to glucose. However, we had the most

difficulty in the conversion of the glucose into ethanol. This did not allow us to

determine the feasibility of the distillation process however we were able to determine

that our system would get up to the desired temperature for fermentation. Time did end

up becoming our biggest restraint because we basically found that everything we did

required additional steps that took more and more time and at the end we ran out of time.

This was especially true with the fermentation process which we were originally told

took 24 hours and which we found out later took three to seven days and pushed us too

late in the year to complete testing. Also as we initially guessed, our system consisted of

many parts which were not complex in themselves but all took time and ingenuity to

build.

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Design Process:

Our goals of starting with corn stalks from the field and producing ethanol that

could be ran through a vehicle were very ambitious. En route to these goals we found an

extremely heavy and varied workload that included computer programming, chemical

analysis, systems engineering, and plenty of hands on work that left us dirty and tired.

We started the process by meeting up with various local farmers to find people willing to

let us on to their personal property to gather corn stover. Additionally, we found a farmer

who was willing to let us run our corn stover through his chopper and this was the

starting point for mechanically breaking down our corn stover. As we did research

online, we found chemical methods that would work as well unfortunately involving heat

and dangerous chemicals. A small experiment in the pretreatment method using diluted

sulfuric acid at room temperature was tried and found to work fairly well.

The story of this project has been that every part of the project has lead to more

complicated analysis and more work. The initial design proved fairly adequate but

involved building an RTD which measured the temperature inside the barrel and used

programmed logic controls to hold our heater at the desired temperature. Small scale lab

work we did to determine the ratios of enzyme to solid, and liquid to solid ratios of our

slurry told us far more practically speaking than chemically. We learned that our slurry

mix needed to use more water than previously thought simply because the corn stover

was dry and absorbed water. Additionally, we found that to measure the effectiveness of

our enzymes in terms of glucose production would involve purchasing even more

chemicals and glass ware than thought as well as learning more chemical procedures.

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The sucrose refractometer we had borrowed from Detail Consulting Inc. for this

procedure showed inconclusive results.

One surprise to us was that the chemical department would prefer us and any

future groups to buy their own glass ware in order to be able to run our experiments in the

engineering labs. A second surprise was that the enzyme we ended up ordering was

easily available through the school and had been around for a couple years. It also was

expensive and did not treat as much enzyme as we had thought it would. This limited us

to running only two batches through our system as well as the small scale lab work.

Some smaller surprises were that the modification to the specs in an attempt to save

money proved unsuccessful. We attempted to save money on the cost of copper by using

¼ in copper piping as a heating coil with a small submergible bilge pump. The bilge

pump failed when it was submerged in hot water due to shorting of the electrical system.

The larger pump we purchased to replace it overheated when we tried reducing the output

from 1 in piping down to ¼ in and forced us to replace our heating coil with one of ½ in

copper tubing.

The experimental work we did involved small scale lab on the different ratios of

liquid: solid and enzyme: solid and proved somewhat successful. Additionally, each

subsystem was tested to determine its functionality such as the heating control system,

the heating system, and the mixing system. Our analysis included the results of the

sucrose refractometry as well as the determination of the amount of enzyme needed for

our batch, and the amount of yeast needed as well. Additionally we used a hydrometer to

determine the alcohol content of our finished product.

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Design Challenges:

There were certain aspects of the proposed project we anticipated to cause

difficulties. First and foremost we were not sure if we would be able to regulate our

temperature as tightly as we wanted for efficient production of glucose and ethanol. All

of our processes were dependent on temperature in some way and were the temperature

to get too warm during say fermentation, our yeast would be killed off before all of the

glucose was converted and prevent us from reaching maximum production. We also

were looking at pretreatment options that involved strong chemicals and possibly high

heats and then a return to neutralization. Since none of us were skilled chemists, to get

the ratios of acids and bases correct to neutralize the slurry required some research and

assistance to complete while also following safety precautions.

A great deal of our project involved doing research not to find parts that would do

the jobs but the cheapest part that would satisfy the requirements and not blow our

budget. We were not able to mix our slurry as completely as we initially wanted due to

power constraints on the motor we used. However, research into a more powerful motor

such as a motor used to mix milk in a bulk milk tank ran over $200’s and therefore were

not suitable. Additionally, the chemical used in pretreatment, sulfuric acid, was over fifty

dollars for 500mL if purchased from a lab; however through research we found a product

consisting of 90% sulfuric acid for only ten dollars for almost a thousand mL and found

sodium bicarbonate to neutralize it in its pure form in another product also readily

available. While these products are not suitable for lab work, they were effective for our

application generating around 4-5 times as much glucose after pretreatment than what we

had gotten without them.

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Another challenge for the design was making it easy to modify at a later point in

time if in fact it did turn out to be economical. We were able to make it easily modifiable

and if the end consumer used any form of circulating water to heat his home or shop, this

design could be converted to run off that source of heat rather easily. Since distillation

costs are 60% of the total cost in commercial applications, we see this as a major benefit

of our system. Additionally, the consumer could also probably eliminate the circulating

motor on our system and use his own for that as well. We did end of replacing the

cartridge heaters of the original design with water heater elements because we found the

water heaters to be less sensitive to overheating and burning out due to being built to be

submerged.

The last design challenge we faced was making the system profitable and we felt

that this would probably be our greatest challenge due to the low returns available even

on the commercial scale. We found that our system was nowheres near profitable mostly

due to the high cost of enzyme per glucose made. However, we feel that the technology

will only continue to improve and become cheaper and that this factor will be less of a

limitation in later years. Additionally, more testing might even find ways of getting even

better yields than what we were able to get from it were someone to be able to focus on

this portion of the experiment in a way we were unable too due to time and budget

constraints.

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Analysis and Experimental Work:

We conducted some experimentation with different ways of storage in that we

stored corn stover in different forms. We stored some of it in small square bales as it was

from the fields and stored it inside a tool shed however, left alone, it began to get moldy

and needed to be stacked by hand in such a way it touched other bales as little as possible

and could dry out. We have also gathered some corn stover in the complete stalk form

before combining which we then chopped before use. We also gathered shredded corn

stover after combining and stored it in that manner. We also immediately ran some of the

corn stover that had been run through a combine through a chopper and stored it in

barrels. Lastly, we ran some corn stover of the chopped corn stover through a modified

leaf vacuum in order to further reduce it to the size we wanted and this was the corn

stover used in our testing. Also we arranged for our corn stover to be analyzed by a

nutritionist to see what energy content it has and those results are in the appendix.

Additionally, we ran small scale testing with samples batches of corn slurry at different

mixes of corn stover, enzyme, and water to determine the proper ratios needed.

We did various test to confirm the functionability of our system, such as setting

the temperature to various temperature and comparing the results to independent

thermometers. We also ran just a sugar batch where we took a known amount of sugar

and water, calculated the percent volume of sugar, and then compared the refractometer

reading to it. We then added yeast to it in an attempt to check our fermentation process

and it was this test that caused us to determine that our fermentation process was not

working properly. Any ethanol made would have been tested with ASTM D4806

Standard Specification for Denatured Fuel Ethanol for Blending with Gasoline for use as

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Automotive Spark-Ignition Engine Fuel. This ASTM standard is considered the industrial

standard for ethanol however we unfortunately never reached this step.

Specifications:

• Must fit in size of standard one car garage. • Must produce one gallon of ethanol per batch. • Must use parts with total value under $500 • All electrical devices must run on standard 120VAC. • Corn stover must be less than ¼”. • System needs to withstand 220ºF • Vessels must have at least 30 gallon capacity • Heating system must be able to use interchangeable heat sources • Control system for heater needs to be adjustable for multiple temperatures • Must comply with TTB permit, in appendix. • Must use only corn stover as biomass

Subsystems:

Grinding mechanism of some sort, slurry tank, Heating systems, mixing systems,

distillation system, temperature control device

Grinding-

• all corn stover particulate should be less than ¼ of an inch in both length and diameter and preferably smaller

Slurry tank

• Needs to be able to hold approximately 30 -50 gallons of corn Stover and water • Need to withstand heat up to100ºCelsius without losing its structural integrity • Needs to be able to accommodate some sort of heating system that can be easily

be added or removed • Needs to be accommodate some sort of mixing system to mix the slurry • Insulated • Chemically inert- possible that it will be exposed to sulfurous acid

Fermentation tank

• Needs to be able to hold approximately 30 -50 gallons of corn Stover and water

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• Need to withstand heat up to100ºCelsius without losing its structural integrity • Needs to be able to accommodate some sort of heating system that can be easily

be added or removed • Needs to be accommodate some sort of mixing system to mix the slurry • Insulated

Distillation tank

• Needs to be able to hold approximately 30 -50 gallons of corn Stover and water • Need to withstand heat up to 77.8 degrees Celsius without losing its structural

integrity • Needs to be able to accommodate some sort of heating system that can be easily

be added or removed • Needs to be accommodate some sort of mixing system to mix the slurry • Insulated • Needs to be air tight to prevent the escape of any evaporated ethanol vapor • Lead to a condensation tank

Because the specification for the slurry tank, fermentation tank, and distillation tank are

all very similar, we are looking at using one system with various attachments to

accomplish all three processes

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Condensation process

• Needs to be able to quickly cool ethanol vapor below its liquid temperature

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Heating System

• Need to be able to hold the process at a consistent temperature • Need to be able to set the holding temperature to various needed temperatures • Efficient use of energy in the heating system • Does not need to be removable • Low energy use circulating pump w/ continuous operating copacity • Able to be switched on and off multiple times

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Mixing system

• Able to fit inside the heating system • Fairly air tight • Able to withstand high amounts of torque exerted on lid and mountings • Able to be added or removed easily • Able to thoroughly mix slurry mixture at a constant temperature • Able to adjust the speed of the mixer

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Temperature Control Device • Able to measure and maintain a constant temperature based on input versus

desired input • Control power source to heaters, regulate on/off based on temperature reading of

barrel

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Process Flow Diagram

Corn Stover is ground with the modified leaf vac

Step 1 Corn Stover,

Water, And Enzyme

Are Added to the barrel

Step 2Heating System

Set to 75°F

Step 3Sugar Level Is Checked

Step 4

Yeast is added And left to ferment

Step 5 Heating System

Set to 190°F

Step 6Ethanol is cooked off and distilled.

Step 7Ethanol is redistilled Until 190 proof is Reached.

Step 8

Complete design of system:

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Subsystems: Grinding mechanism, Slurry tank, Heating systems, Mixing systems, Distillation system, Temperature control device Grinding Mechanism

• We are looking to use a modified leaf vacuum with shredding capacity to reduce our corn stover to particulate matter under aproximatly ¼ inch.

• We will remove a side or bottom of the vacuum leaf blower and spot weld a screen through which the particulate matter will have to pass through to ensure it is reduced to the desires size

• If this is unsuccessful, we are also looking at the option of using a hammer mill, which is similar in principle with the particulate screen but a higher powered version and will more thoroughly beat the corn matter and reduce the size

The Slurry tank

• Because the slurry tank will also be used as the fermentation tank and the distillation tank, its design needs to be flexible enough to accommodate all the accessories used for those processes as well

• The slurry tank will consist of a modified 55 gallon steel drum or possible a high density plastic drum able to withstand the high heat needed for distillation.

• The slurry tank will be insulated with eight or twelve inch thick fiberglass insulation wrapped around the barrel

The Heating system

• The heating system will consist of copper piping installed inside the barrel through which hot water is run to heat up the slurry mix.

• A hot water reservoir will be maintained outside the system at the desired temperature or possible slightly above to compensate for heat loss of the system

• A circulating pump will run continuously circulating water from the hot water reservoir through the copper piping and back into the reservoir

• A float system could be used on the hot water reservoir to prevent it from running dry and burning itself up

• The water will be heated by four 100 watt cartridge heaters inserted though the side of the hot water reservoir

• A device will be used to control the temperature of the hot water reservoir by turning them on or off as needed.

• This device will measure the desired output of the system (required temperature within the barrel) against the actual output (actual temperature within the barrel) and based on that regulate power to the cartridge heaters.

• The copper piping will be either ¾ or one inch in diameter in order to reduce flow work required to pump water though the system.

• The copper piping will be coiled tighter at the bottom of the barrel that the top to compensate for the higher temperature needed at the end of the system when less fluid will be in the tank than initially

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Mixing System • An electric drill will be used to power the mixer device • A mixer paddle will be designed and made that can be inserted into the end of an

electric drill • The drill and mixer attachment will be mounted on a lid that securely attaches to

the barrel • The lid must fit tightly on the top of the barrel, preferably with some sort of

gasket seal, possibly of rubber. • The mixer attachment will be sealed as best as possible where it goes though the

lid (note: the lid does not need to be airtight but should extremely limit airflow into the system)

• The electric drill must be securely mounted on the top of the lid • A small closable hole or pipe should be on the lid in order to add the needed

enzyme or water to the slurry Distillation system

• The top of the barrel must be airtight with a 2 inch hole for the evaporated ethanol vapor to go through

• A pipe will lead from the hole to a cooling device where the vapor will be condensed into a liquid

• The cooling device will be the radiator of a car with a fan blowing upon it to further dissipate heat

• The piping will drop the liquid ethanol into a storage container of some kind

Construction:

Our construction turned out to be a continuous process of constantly modifying

the 55 gallon barrel we started out with all the necessary components. Construction

began with basic additions to the barrel such as handles in order to easily move it around.

The mobility of the system was enhanced even more with pulleys welded on top of the

handles that allowed lifting of even a fully loaded barrel. Next, a drain was installed in

the barrel to allow us to drain liquid from the barrel and this was done with a simple two

inch iron nipple which was welded to the bottom and closed with a cap. This drain

allowed us to dispose of the waste left after the distillation. We actually found we had to

reinforced the metal on the bottom of the barrel with a square of thin gauge metal to

allow sufficient welding to stop all leaks in the bottom. Next we added a vent to the side

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of the barrel by making a small ¾ inch hole and again welding a nipple to it to which we

attached copper tubing with a ball valve to open and close as necessary. This allowed

us to use the original top to the barrel which created a tight seal that was necessary for

fermentation and distillation. We planned on boiling ethanol, and then condensing it

outside of the tank. If the seal is not good, much of the ethanol will escape, and we will

not be able to collect it.

The heating system required more modifications to the barrel in that we created a

hot water reservoir on the barrel. This served a two-fold purpose. First it was handy to

have the reservoir close to the heating coil to which it needed to circulate through.

Secondly it allowed part of the heat lost from the reservoir to go into the barrel that it was

heating, reducing the total heat loss of the system. The heating coil of the system

consisted of ½ inch bendable copper coiled inside the barrel approximately one inch from

the side of the barrel and about two inches away from the pipe above and below it. This

coil was help into place by 1 ½ inch angle iron pieces welded to the barrel such that the

coil was held in the 90 degree angle. Two holes were drilled through the side of the

barrel above the reservoir and iron nipples were welded on to allow the pipe to be

screwed in with out compromising the air tightness of the barrel. The ends of the coil

were fitted with fittings that could screw off to allow the coil to be removed if necessary.

We initially tried to use a heating coil made of coiled ¼ inch copper tubing due to its

reduced cost but found we were unable to circulate enough heat through the system to

adequately heat it and it caused problems with our circulating system.

Our original circulating system consisting of a small bilge pump which could be

submerged in the hot water reservoir. This pump was relatively inexpensive and worked

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with the ¼ inch copper tubing. However we found that when the pump was subjected to

high temperatures the glue holding the housing of the pump together dissolved and the

pump shorted out. We replaced it with a larger pump with a one inch inlet and outlet and

found that reducing the outlet to fit the ¼ inch tubing caused the pump to overheat.

Therefor, we replaced the ¼ copper tubing with ½ inch copper tubing and this allowed

sufficient flow to circulate the antifreeze without overheating the pump.

The antifreeze is heated by a 1300 W hot water element that was inserted through

a hole in the side of the heating reservoir and sealed off. We found that level of

antifreeze in the reservoir varied a little as we ran the tests due to evaporation and this

made the cartridge heaters unsuitable because if any portion of them were out of the

liquid, they burned themselves out. However, if were submerged at all they shorted out

and no longer worked so the alternative water heater element was tried and found to work

vary well.

Our mixing system changed from our original idea of simply using a drill

mounted vertically. This was due in part the amount of power we found it took to mix

the slurry. Also, we realized that to build a shaft that would fit in the ½ inch chuck of a

drill would be very flexible and hard to hard in the chuck. The design we went with was

a vertically mounted motor with an inch shaft extending into the barrel. The 1 inch shaft

was not long enough to reach the slurry so a ½ rod was welded on the end to which

mixing blades were attached to mix the slurry. Because this motor belonged to a group

member, we were not able to modify it as ideally as we could have but it worked fairly

well.

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The last major system we built was the distillation apparatus. This consisted of

coil of the leftover ¼ inch tubing which we attached through to the vent on the side and

ran through a bucket of cold water into a container underneath. The important aspect of

this system was to make the sure the hole where the copper tubing ran through the bucket

was sealed with gasket material because any leaks would allow cold water from the

bucket to run into the storage container for ethanol and require additional distillation to

remove. We had planned on our ethanol coming out through a hole on the top of the lid

but found it much easier to put the vent on the side and feel that is just as effective.

Because the vent on the side wasn’t completely at the top of the barrel but very close, it is

possible that some evaporated ethanol would remain above the vent at the lid but this

should be a negligible amount of ethanol. We had also planned on using a car radiator

for distillation but feel it would have been more difficult then our current system and no

more effective.

Testing/Evaluation:

Testing was done on each component of our subsystems to ensure they completed

their intended function. The heating system was tested first by filling our barrel with

water and turning on our heating system and checking to ensure the water was heating.

This was also a test of our temperature control system in that we set the desired

temperature of the system to see if the temperature control system would turn the heater

off when the desired temperature was reached. The mixing system was tested first with

just water to ensure it had the power to turn the mixture but when corn stover was added

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we found it caught on the blades and so some blades had to be removed. We were not

able to test the distillation process due to time constraints.

Overall, we met several of our objectives which we made before we really got

fully involved in this. We did identify and procure all necessary additives for a

functional cellulose based ethanol plant. The cellulase we bought was effective and did

convert cellulose into glucose although not as effectively as we thought it would. The

yeast we used did convert the glucose into ethanol although not nearly in the quantities

we thought it would and it is possible that further research would turn up a more efficient

alternative to what we used, but most likely at a much higher cost as well. We did build

an ethanol plant capable of producing one gallon of ethanol per batch, in fact much more

than one gallon of ethanol per batch.

Due to the fact we were never able to get our fermentation process to work, we

were not able to complete objectives three and five. However, based on measured sugar

level readings that we took throughout our process, we were able to estimate the

efficiency of our system in order to see if economic gain was possible. As hinted at

before, we found the chemical reactions were very inefficient in terms of the amount of

glucose we were able to convert from cellulose. Using chemical pretreatment increased

the amount of glucose converted but added additional cost to the system and in the end

negated any economic gains. An initial cost per gallon based on the cost of additives was

around $80 per gallon of ethanol produced. As high as this is, we feel that future groups

focusing on the chemical side of the process could greatly increase the efficiency of the

reactions and lower the cost of conversion of cellulose into glucose. Additionally, as

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commercial production picks up, we expect to see the cost of additives drop as the

number of suppliers increase and this will make the process more economical as well.

Our final design met all specifications laid out for it in turns of cost, size, and

capabilities. We found that our original specs for each subsystem turned out to be a fairly

accurate representation of the final system and almost all deviations from the specs in

attempts to save money were unsuccessful. We were able to combine several subsystems

similar in nature such as the distillation, fermentation, and the slurry tank as planned and

this helped cut down redundant parts of our system. The only adverse effect of this

decision was that it limited the rate of production because we had to run all batches

completely through before we could start the next. Physically our system was able to

meet all objectives but further work is needed on the chemical reactions in order to

produce a final product.

Budget:

Gifts in Kind Temperature Control System $350.001/2 inch Flexible Copper Pipe $60.0055 Gallon Drum $20.00 Hardware Parts Angle Iron $10.00Pulleys $40.00Sheet metal $10.00Fittings, Hose Clamps $15.00Water Pump $45.00Rope $12.00water heater $8.00pipe for distillation $20.00supplies for box $50.00 Tools/Parts inert welding gas $36.00welding wire $10.00grinder wheels $5.00

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Additives/Chemicals Enzyme $65.00Yeast $10.00Sulfuric Acid $10.00Sodium Bicarbonate $15.00 Replaced Parts Bilge pump $15.00some copper tubing $10.00 $816.00

Our project was a prototype, and will continue to be. Attempting to calculate the cost of

an actual system does not make sense for this year. If this project continues, future

groups will be able to truly identify the cost of the system, and the cost of running the

system per batch.

Conclusions:

Despite the fact that we did not produce any ethanol, we feel that we made a

substantial amount of progress toward our ultimate goal. The goal of this project was to

determine whether cellulosic ethanol production on a small scale is possible, and if it is

possible, to determine the possible economic gain. When we developed our objectives,

we did so with all this in mind. Our overall conclusion is that cellulosic ethanol

production on a small scale is possible. By taking sugar levels before and after the

addition of our enzyme, we determined that the enzyme was performing as we had hoped,

and broke down the complex sugars into the necessary simple sugars. Once this is

complete, the fermentation process is fairly simple. We did not have enough time to

complete this process, because of necessary deadlines as well as unanticipated system

problems. However, if this were to be continued, the fermentation process is easily

understood and simple to implement. After the slurry is fermented, the mash needs to be

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distilled, which is also a basic procedure. We do know that our system is capable of

maintaining temperature requirements of each of these processes, which we found

encouraging. Given enough time, we could easily produce the small amount of ethanol

we had hoped to produce.

However, despite being able to produce the ethanol, we also needed to analyze the

process from a monetary perspective. Though we did not finish the distillation process,

we know from simple sugar readings that any ethanol produced would cost a minimum of

80 dollars per gallon. This easily leads us to the conclusion that a monetary gain is

impossible on such a small scale.

Our specific objectives were

1. Identify and procure necessary additives for a functional cellulose based ethanol

plant.

2. Build an ethanol plant capable of producing one gallon of ethanol per batch.

3. Replicate the process and achieve a constant 190 proof product.

4. Identify and analyze the cost of the process and plant to see if an economic gain is

possible

5. Produce 10 gallons of ethanol by May 2007.

We met our first objective, though we did not exhaust our possibilities for our enzyme. If

we were given more time and money, it is possible that we could find better additives,

and determine better ratios to improve the efficiency of the process, and help to lower the

cost.

We met our second objective as well, in fact exceeding it by a significant amount.

Our system is theoretically capable of producing a batch as large as 5 gallons, well above

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our stated goal of 1 gallon. This value is theoretical, and we were not able to run a batch

as large as we wanted because of the high expense of our additives.

We did not meet our third objective, though we do believe that our system would

be capable of meeting the objective if we had more time and money.

We met objective four, even though our findings were not so encouraging for

future work. As stated above, the cost of 80 dollars a gallon clearly indicates that an

economic gain on such a small scale is not possible for the time being. With future

advancements on the enzyme, and more experimental work, the cost could be dropped.

However, the cost is too overwhelming for any improvements to make the process

profitable.

Our last objective we could also have met if we were given more time and money.

However, given our conclusions on the fourth objective, producing 10 gallons of ethanol

would have been, quite simply, a waste of money for the time being. If there are

improvements made in the future small scale production can again be investigated, but

for the time being the cost is simply too high for production to make sense.

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Future Work:

Future groups will need to rebuild the circulating pump, and replace the pipe

insulation and lid for the hot water reservoir, as they were damaged in an overheating

incident. Also experimental work with fermentation needs to be done. Yeast is very

temperamental when making alcohol so they would need to practice, and get a technical

advisor from a brewery or vineyard. Additionally, pretreatment needs to be worked into

the process. The work we did with pretreatment was experimental and not streamlined to

fit into the process. Another option for future work is to find a “free” heat source. That

is, find a source of waste heat capable of heating up the hot water reservoir to around

200˚F.

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Appendices:

Calculations: Corn stover gathered:

Five truckloads of stover were gathered by hand

Each truckload was about 34 Ft^3

The approximate area it took to gather each truckload was about 730 ft^2 of surface area,

however, we are limited in the use of this information because we don’t know the weight

With machinery

One trip around a 13 acre field with pick up width of about 8 feet covered about 12,000

ft^2 and picked up about 70 bales at 50 pounds apiece, for a total weight of 3500 lbs of

stover, limited because we don’t know area, plus its baled therefore compressed

According to information from Popular Mechanic, we should be able to get about 300

gallons of cellulosic ethanol per acre and as an acre is 43,560 ft^2, we should expect to

get about 75 gallons from the corn stover gathered with machinery because of the area

gathered is about a fourth of an acre. However, it is possible we will get less because the

pickup on the baler was higher than it could have been and material was left in the field.

ftftArea 3*2*π= Thickness of insulation=6”= .5 ft

Conduction Coefficient of insulation = Km

W204.

=Kft

WL 2

10044.

tkaq Δ= t1=0 oC t2=87 oC a=3ft*2ft*π +2*π (1ft)2=8π ft2

q=ftKft

W5.10044. 2 * 8 π ft2 *(87 oC-0 oC)

q=20 watts This is the theoretical heat lost to the environment through the insulation.

While this is only a rough calculation, it is enough to justify our insulation and heating system.

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Drawings:

Saccharification

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Fermentation:

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Distillation:

37

38

39

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David Irvin

5279 East Trindle Road Phone (717)697-9633 Mechanicsburg, PA, 17050 E-mail DOC2884@comcast.net

Objective To use the engineering skills and practical knowledge I have acquired, to aid in the engineering tasks of this company.

Education 2003-2007 Messiah College Grantham, PA.B.S. Engineering, Focus Mechanical 2.65 GPA Minor in Music

2002-2003 Harrisburg Area Community College Harrisburg, PA. General Studies Member of Phi Theta Kappa

Work experience 2002-Present Plexus Scientific Columbia, MD.Engineer’s Assistant Operated a groundwater remediation facility in New Cumberland, PA. Collected N.P.D.E.S. samples. Aided in the construction of a methane recovery system on Ft. Meade

MD. Aided in the construction of a research and development facility on

Piccatinny Arsenal, NJ.

Related Experience

Designed, built, and tested an alternative energy project to produce ethanol from the cellulose in corn stalks.

Designed a passive arsenic filter using an ion exchange resin, for the Indian subcontinent.

Accreditations and licenses

OSHA 40 hour HAZWOPER

Current OSHA 8 hour HAZWOPER refresher

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Computer Skills Microsoft Office, IDEAS, Q-Basic

Awards received Eagle Scout Rank, 2002

Interests and activities

I enjoy performing live music in the Harrisburg Area Concert Band, traveling, and studying history.

Jeffrey Bennett Address: Box 5098 One College Avenue, Grantham PA, 17027 Email: jb1390@messiah.edu Phone: 860-367-4744 Objective: -To apply my Mechanical Engineering education to implement technology in a hands on environment Education: -Bachelor of Science in Mechanical Engineering, May 2007 -General Music Minor Messiah College, Grantham PA Senior Project -worked as part of a team to design and build a small scale ethanol production plant -implemented and adapted cutting edge technology to achieve our goal -developed a clear idea of the ethanol infrastructure and future of ethanol in our energy supply -extensive testing to determine the necessary steps to make the plant reliable and affordable Related Experience: -Began and developed my own landscaping business -Worked with customers, developed contracts, and supervised employees -Improved interpersonal skills -Demonstrated ability to work under pressure -Worked at a John Deere dealership as a mechanic -Gained experience working in a hazardous environment -Also worked at the counter, dealing with customers and managing cash flow Summary of Skills: -Able to apply engineering education in a practical sense -Extensive mechanical background in small engine and auto repair -Ability to work with other engineers -Excellent problem-solving skills -Computer skills-Microsoft Windows, Word, Excel, PowerPoint, some experience with AutoCAD and other drafting programs

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Other Activities: -Concert Master in College Wind Ensemble -Member of College Jazz Band -Member of local church worship team

Vaughn L. Moser vm1164@messiah.edu

Current Address: PO Box 6101, One College Avenue, Grantham, PA 17027, Cell: (315) 486-0124 ermanent Address: 3981Wilson Rd., Copenhagen, NY 13626, Home: (315) 688-2518 P

OBJECTIVE:

T

o obtain a full time position related to Mechanical Engineering.

EDUCATION: Messiah College, School of Engineering, Mechanical Concentration, Grantham, PA 2005-Fall 2007 Fourth year towards the Bachelor of Engineering Degree (December of 2007) Major: Bachelor of Science in Engineering with a concentration in Mechanical engineering Current GPA: 2.38 (junior year only, GPA of transfer credits do not apply) Financed 100% of education th

rough a summer job, scholarships, grants, and loans

Jefferson Community College (JCC), Watertown, NY 2002-2004 Associate of Science Degree (Class of 2004) Major: Engineering Science Cumulative GPA: 2.97 F

inanced 100% of education through a summer job, scholarships, and grants

Rosedale Bible College (RBC), Rosedale, OH 2004-2005 Major: undeclared Cumulative GPA: 3.33

SENIOR PROJECT: Conversion of corn stover into ethanol by designing and building a system that uses enzymatic and hydrolysis rocesses p

WORKS EXPERIENCE:

Lyndon Moser Farm, Copenhagen, NY Summer 1994 – present • Machine operation and maintenance of all types of equipment/ Night milker and herdsmen • Maple Syrup operation • Develop personal work ethics, mechanical skills, ability to work independently

New York Air Brake, Watertown, NY Summer 2006 • Designed and carried out modifications to lab components • Created needed components from electrical schematics • Specified modifications for engineering drawings

Self-Employed Contractor, Lewis County, NY Summer 2002 - present • Developed trade skills: foundations, framing, and finish work • Work on wood structures: residential housing and commercial farms • Use critical thinking and leadership skills • Demonstrate ability to work independently or within a group

SPECIALIZED SKILLS: • Knowledge of CadKey, AutoCAD, Microsoft Office, Adobe 5.0, MATLAB, Minitab, and Derive.

RELEVANT COURSES:

Dynamics • Statics • Graphics, CADD • Programming - C++ • Fluid Mechanics • Thermodynamics • Mechanical Design • Engineering Economics • Experimental methods • Control Systems • Instrumentation and Measurement •

uality Control • Materials Engineering Q

AWARDS AND SCHOLARSHIPS:

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• Norbert L. Gazin Scholarship 2000 - 2004 • Lowville Farmers Cooperative Scholarship 2000 - 2004

AFFILIATIONS:

• JCC Baseball team 2002 – 2004 • Messiah Baseball team 2005 – Present • TYESA (Two Year Engineering Science Association) ,

COMMUNITY ACTIVITIES:

Abba’s Place: worked with underprivileged kids in Harrisburg area Fall 2005

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