CO to CO2 Filter Implementation

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Carbon Monoxide

ToCarbon DioxideFilter Implementation

Neal Bloom, Isaiah Freerkson, Brian Rose, Sean Youtsey

MAE 156B- Fundamental Principles of Mechanical Design IIUniversity of California- San DiegoProfessor Jerry Tustaniwskyj, Ph.D.

June 8, 2008


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Abstract

Modern day air purifiers are capable of cleaning large particulate matter down to a

standard 0 .3 microns. This usually takes out dust, pollen, mold spores, and pet dander, but is

not capable of removing airborne chemicals. There are many chemicals in the average home,

like formaldehyde, ammonia, and carbon monoxide, which are dangerous over prolonged

periods of exposure, regardless of the concentration. It would be helpful to have a way to clean

these out.

Quantum Group of Mira Mesa, California has a long history of developing and

manufacturing carbon monoxide safety equipment. The companys proprietary carbon monoxide

to carbon dioxide (CO CO 2) catalyst has been essential in their success. The MAE156B group

was charged with taking Quantums existing carbon monoxide to carbon dioxide catalyst

technology and implementing it into a product. The product that was chosen for the group is the

modern day air purifier, for the reason explained before, about most air purifiers do not finish

the job of keeping a house as clean as possible. This team made a filter with their catalyst and fit

it into an air purifier and then tested its effectiveness of lowering carbon monoxide

concentrations in the average home. The main objective was to characterize the catalyst in an

air purifier by testing different thicknesses of catalyst beads, which was successfully completed.

A visible goal was set to clean a 2000 cubic foot room of 30 parts per million carbon monoxide

to an undetectable amount in a given hour and through the small-scale testing that was

completed, it was shown that this was not feasible. The group has been able to clean 30 parts per

million in a 39.5 cubic foot room in 11 minutes in laboratory tests.


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Table of Contents

Abstract .................................................................................................................................................... 2

List of Figures ......................................................................................................................................... 5 List of Tables........................................................................................................................................... 6

Executive Summary.............................................................................................................................. 7 Project objective ............................................................................................................................................... 7 Design solution ..................................................................................................................................................8

Project Description............................................................................................................................... 7 Background.........................................................................................................................................................9 Review of Existing Designs Solutions ..................................................................................................... 10 Statement of Requirements ....................................................................................................................... 11 Deliverables..................................................................................................................................................... 12

Definitions of where and how the project will be used.................................................................... 12 Design Solutions Considered ..........................................................................................................12

Primary Designs Considered ..................................................................................................................... 12 Catalyst Filter................................................................................................................................................................12 Carbon Filter .................................................................................................................................................................13

Risk Reduction Effort ................................................................................................................................... 14 Justification of your design choice........................................................................................................... 14

Description of Final Design..............................................................................................................15 Assumptions regarding scope of project............................................................................................... 15 Summary of Final Design (overview of how it works) ..................................................................... 17

Overview.........................................................................................................................................................................17 Carbon Filter .................................................................................................................................................................18

Description of how it works......................................................................................................................................................18 Justification of your design decisions....................................................................................................................................19 Purchased engineering components and selection justification................................................................................20 Analysis used for sizing and design ....................................................................................................................................... 20

Catalyst Filter................................................................................................................................................................21 Description of how it works......................................................................................................................................................22 Justification of your design decisions....................................................................................................................................22 Purchased engineering components and selection justification................................................................................25 Analysis used for sizing and design ....................................................................................................................................... 26

Analysis of Performance...................................................................................................................27 Air Flow ............................................................................................................................................................. 27

Assumptions..................................................................................................................................................................27 Analytical Methods Used..........................................................................................................................................27 Analytical Results........................................................................................................................................................29

Analysis of Performance...................................................................................................................31 Catalyst Performance................................................................................................................................... 31 Method 1: Empirical Model ........................................................................................................................ 31

Assumptions..................................................................................................................................................................31 Analytical Methods Used..........................................................................................................................................33


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List of Figures

FIGURE 1: IQ AIR............................................................................................................................................................................................. FIGURE 2: CUT AWAY VIEW OF IQ AIR ..........................................................................................................................................................1 FIGURE 3: FINAL FILTER DESIGN (CARBON & CATALYST).........................................................................................................................17 FIGURE 4: SANDWICH DESIGN OF FILTER ......................................................................................................................................................1 FIGURE 5: CO FILTER IMPLEMENTATION INTO IQ AIR ...............................................................................................................................18 FIGURE 6: AIR FLOW CHARACTERISTICS OF EACH TYPE OFCARBON SYSTEM.........................................................................................19 FIGURE 7:MAIN BODY OFCATALYST FILTER BEFORE FILLING WITH CATALYST ......................................................................................21 FIGURE 8: COMPLETE CATALYST FILTER BEFORE TOP IS ATTACHED .........................................................................................................22 FIGURE 9:N YLONMESH WITH POUR SIZE


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List of Tables

TABLE I: REQUIREMENTS FOR FILTER ............................................................................................................................................................1 TABLE II: 2ND ORDER POLYNOMIAL REGRESSION COEFFICIENTS ..............................................................................................................29 TABLE III: R2 VALUES FOR DIFFERENT REGRESSIONS .................................................................................................................................35 TABLE IV: R^2 VALUES FOR DIFFERENT REGRESSIONS...............................................................................................................................37 TABLE V: PROJECTEDCOST FOR PRODUCTION DESIGN................................................................................................................................54 TABLE VI: TEAM TASKDESCRIPTIONS...........................................................................................................................................................5 TABLE VII: BUDGET.........................................................................................................................................................................................


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Executive Summary

Project objective In the world of air purifiers that are currently on the market there is not one that can

eliminate the carbon monoxides from the air it processes. The importance of the removal is to

eliminate the side effects of carbon monoxide poisoning. Some of the side effects of carbon

monoxide are headaches, nausea, vomiting, dizziness, shortness of breath and even death. The

objective of this project is to utilize a proprietary carbon monoxide catalyst to reduce carbon

monoxide for living spaces. The target is to remove a carbon monoxide concentration of 30 parts

per million from a 2000 cubic foot room in one hour. This target must be achieved consistently

for one year which is the chosen life of catalyst system. This task must be completed using air

purifier systems that are on the market. The purpose of this is to market the carbon monoxide

removing system to air purifier companies. The system optimally will fit inside current air

purifiers without any modifications; this will insure a smooth transition into the current market.

This catalyst consists of small silica beads approximately 1-2 mm in diameter coated with a

proprietary agent. The catalyst utilizes a chemical reaction in which it places an extra oxygen

molecule onto the carbon monoxide thus creating a molecule of carbon dioxide. To properly,

utilize the strengths of the catalyst there are several crucial limitations that must be investigated.

(1) Contamination by common house hold agents can render the catalyst incapable of processing

carbon monoxide. (2) The catalyst will have air passed through them thus creating a resistance to

the standard flow of the air purifiers this creates a pressure drop and can affect the way the

catalyst removes the carbon monoxide. In addition to the catalyst the carbon must be protected

by an activated carbon product this will increase the pressure drop experienced by the air purifier


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system. (3) The catalyst also has sensitivity to particular containment materials. These limitations

were investigated and were subverted with positive results.

Design solution In the quest for a solution to our limitations much research and testing was conducted.

The design that was finalized was as follows. Catalyst containment was achieved through the use

of a frame made of acrylic and a containment mesh made of nylon mesh. Both of these materials

are compatible with the catalyst and provide an inexpensive and simple solution to the

manufacturing process. Testing of the catalyst effectiveness provided a thickness of inches,

which provided a pressure drop of 1.5 inches of water. Effectiveness was tested by varying

thickness of the catalyst and the velocity at which air was passed through the catalyst

containment. Within the catalyst containment carbon beads were also housed to provide

protection from catalyst killing house-hold agents. The individual carbon beads measure 0.0039

of an inch on average and were tested to provide optimum protection at a thickness1/2 of an inch

with a low pressure drop of 1 inches of water. The optimum thickness of the carbon filter was

determined using the assumption that it must absorb all the background ammonia in an average

house hold over the course of one year. The carbon must remove all the ammonia to assure the

life of the catalyst is maintained.

The air purifier that was chosen as the optimal system was the IQ air. It was chosen due

to its robust design, a high quality and powerful fan and it provided the most room to locate the

carbon monoxide converting unit. It was early in testing that the team realized that the initial

requirement was not going to be met. The time it was taking to clean the small test chamber

which is 50 times smaller than the intended room size. The system theoretically scrubs out all the

carbon monoxide in 16 hours this is 16 times that initial requirement. With this finding the initial


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condition are eliminated. The system also was tested at much higher concentrations and it is

found that it extremely effective at high concentrations of carbon monoxide. This will enable the

catalyst to be used as an emergency purging system. Future investigations to find new solutions

that would place the system much closer to the initial condition requirement will have to be

under taken.

Project Description

Background Carbon monoxide is a colorless, odorless gas that is a by-product of incomplete

combustion. Many household appliances produce carbon monoxide, which can have harmful

effects, even at low levels. Side effects range from headaches to nausea to shortness of breath

and depending on the concentration and length of time of exposure, could lead to death,

especially in fetuses, infants, elderly people, people with anemia or a history of heart or

respiratory disease.

Quantum Group was founded in 1982 and first made fire safety equipment for the nuclear

power industry. It then developed the worlds first biomimetric carbon monoxide sensor and

began manufacturing carbon monoxide safety products in 1989. Today their products range from

carbon monoxide detectors, sensors and controls. They make products for the car, the home, RV

and watercraft.

Recently, the company has shown interest to expand its market diversity. In recent years,

the company has sponsored a MAE156B project whose purpose was to see if their proprietary

carbon monoxide to carbon dioxide catalyst could be used for emergency gas masks for miners.

The intention was that if a miner were caught in a mine with a sudden outburst of carbon


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monoxide, the mask would enable him to survive the hours until potential rescue. The data found

on this project positively showed that their catalyst did have potential for other uses.

Recent research has shown [8] that the average house could contain around 30

parts per million [ppm] of carbon monoxide that over long term exposure, could lead to disease

and other problems with the health of the inhabitants. The average household air purifier does

not filter out carbon monoxide, as most filters are only capable of filtering out particulate matter,

like bacteria and spores. With Quantums catalyst, an air purifier with the capability to cleanse a

house of a harmful gas is definitely a plus for the market

Review of Existing Designs Solutions There are plenty of air purifiers on the market that will clean particulate matter in the air,

but the list of air purifiers that claim to be able to clean harmful chemicals and molecules is

miniscule. Part of the problem with most air purifiers that include a HEPA filter, is that a HEPA

filter is rated for particles as small as .3 microns and then given a Clean Air Delivery Rating

(CADR) based on how well it filters out tobacco smoke, dust and pollen [1]. Since the size of

measuring is only .3 microns, really HEPA filters are only good for particulate matter, nowhere

near the size of the real dangers from Volatile Organic Gases (VOCs), like formaldehyde and

ammonia, and carbon monoxide, which are all obviously on the molecular level and therefore are

not being filtered out of the air. One of the best products on the market, is the IQ Air seen in

figures 1 and 2 below. Though its also only rated at the .3 micron level, it has the potential to be

upgraded with our successful design. During the SARS epidemic in South Asia, the Hong Kong

Hospital Authority completed a detailed study on the available air purifiers and came to the

conclusion to use the IQ Air in all of their hospitals to keep the chance of spreading the deadly

virus as low as possible [2,3,4].


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Figure 1: The IQ Air Compact air purifier used for proof of concept.

Figure 2: Cut Away View of IQ Air Compact to show the compartmentalization of product.

Statement of Requirements The primary goal of the carbon monoxide to carbon dioxide catalyst filter enhancement is

to reduce the level of carbon monoxide in the room. This has never been attempted with the

CO CO2 catalyst in a small concentration of carbon monoxide, so there are no existing

precedents to follow. The majority of the requirements have come to light during talks with

Quantum and this group. They are listed in Table 1 below.

Table I: Requirements for Filter

Issue Requirement

Carbon monoxide reduction Reduce 30ppm to 0ppmSize of room 2000 cubic foot roomTime of clean Reduce in 1 hour


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Material Compatibility All materials that are in contact with catalystmust not kill it

Activated Carbon Filter Effectively stop any harmful chemicals fromthe catalyst.

Deliverables For the sponsor, we will be first and foremost providing evidence that their catalyst can

actually be applied in dynamic areas, as opposed to their stationary and diffusive carbon

monoxide sensors and alarms. This will mostly be given in the form of data we have collected of

concentration of carbon monoxide vs. time. We have prototype filter that will be given to

Quantum, which fit exactly into the IQ Air Compact for future use, which will contain a catalyst

package along with an activated carbon pre filter.

Definitions of where and how the project will be used This product can be used anywhere an air purifier might be used. The CO filter is

designed to filter low level carbon monoxide found in most homes. This concentration level can

be due to a fireplace, cooking, or having a smoker near by. Since consumers often leave their air

purifiers on continuously, it will aid in alleviating some chronic sicknesses and headaches

associated with low level CO poisoning.

Design Solutions Considered

Primary Designs Considered

Catalyst Filter

The First design considered was a bag design that would contain the spherical catalystbeads. The next iteration it was decided that a single bag design would not be sufficient because

due to bulging. Thus a chamber bag design was created. This bag contained several small

chambers that could be filled with catalyst beads and would not bulge out as much. Another


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possible configuration for our catalyst filter is a honeycomb- Nylon sandwich. This would

allow for an even dispersement of the catalyst in the flow. This would also solve the problem of

bulging because the honeycomb would provide rigid support.

Another possibility is using a completely different substrate for the catalyst. Fiberglass

has been proposed as a possible candidate for a new substrate. This would completely alleviate

the problem of trying to push air to sand. It would also be much easier to implement in a

standard air purifier because it can be shaped into almost anything and once it is coated in the

catalyst it will become rigid, making the need for a secondary support obsolete.

Carbon Filter The second integral part of our design is the activated carbon filter. This filter will

protect the catalyst from volatile organic compounds (VOCs), which would prevent the catalyst

from converting CO to CO 2. This filter was needed to sandwich the catalyst filter in order to

ensure VOCs do not reach the catalyst beads from the top or bottom.

Several different types of carbon filters were considered during the design process. The

top three candidates included carbon beads (.6mm in diameter), carbon felt, and carbon cloth.

The first iteration was to construct a filter for the carbon beads. This filter design would be

exactly the same as the catalyst filter because they, like the catalyst, are spherical and are of

similar diameter.

Given that, the carbon beads are a slightly smaller than the catalyst beads lead to

concerns about pressure drop across the carbon filter. To remedy this, activated carbon cloth wasordered from Calgon Carbon. This cloth is pliable, porous, and can be cut into any size needed.

In addition to the cloth, carbon felt was ordered from McMaster-Carr. The felt seemed like a

strong candidate for our filter because it can be found in air purifiers that are on the market


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already, and therefore it was a viable option for our application. In order for this design to be

viable, it needs to be able to filter out as much or more VOCs than the proven activated carbon

beads.

Risk Reduction Effort In order to test the cubic feet per minute (CFM) and pressure drop across the filter a flow

test chamber was constructed. Its air intake system was constructed to mimic that of a standard

air purifier. A differential pressure manometer was mounted on and in the chamber to measure

the pressure drop and an anemometer was used to measure the CFM drop. This test allowed us

to determine what thicknesses arent viable to use in our filter design. This also provided us with

a curve of CFM and pressure drop vs. thickness of filter. This in conjunction with the CO

concentration vs. time curves will provide us with a systematic way to choose our final filter

design.

The final test was to determine the time it takes to reduce the CO concentration from

30ppm to 0ppm in test chamber. The flow settings were calculated using dimensionless analysis

to account for the smaller test chamber. These tests will deliver the CO concentration vs. time

curves for different thicknesses and as stated before this will be used to systematically choose

our final design.

Justification of your design choice

Several factors will go into to our final design choice. It must reduce the concentration of

CO from 30ppm to approximately 0ppm in a 2000 ft 3 room as quickly as possible. Second it

must not completely diminish the flow rate of the air purifier. Third it must fit into the IQ Air.

And lastly it must not decrease the life of the HEPA filter.


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Description of Final Design

Assumptions regarding scope of project Since the aim of this project was to implement the catalyst into an existing air purifier

several assumptions had to be made in order bring the concept to a product. First and foremost,

the IQ Air was chosen because it was a high-end, on the market, air purifier and had a powerful

fan. In order to implement the CO filter in the purifier, the pre-HEPA particulate filter was

removed. It was assumed that the catalyst/carbon filter configuration would block any particles

that would normally be blocked by the pre-filter.

The second major assumption that was used to design the CO air filter was that the

carbon monoxide flowing through the filter had enough time to react with the catalyst at any fan

speed. This was essential because in order for this product to be marketable, it has to add

functionality to the purifier and thus have to work on all available speeds. Also, since this

product is going to be marketed to the average consumer, an average background ammonia level

of 40 ppbh (parts per billion-hour) was assumed. This dose of ammonia has been known to kill

the catalyst after three years of exposure with diffusion. This fact allowed the group to calculate

a kill dose of ammonia for the catalyst, which gave way to a theoretical thickness needed to

protectagainst that amount of ammonia.

For the carbon system, it was known that the .6mm carbon beads were verified to protect

the catalyst in diffusion. This was a proven fact because it is used in their carbon monoxide

detectors, found on the market today. During the designing process, the group assumed that the

carbon beads would also work under the airflow conditions in the air purifier. During the testing

process a large pressure drop was observed using these beads. This lead to the investigation of a

new carbon filter system which lead to the coating of carbon felt and fabric in acid, which would


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make the carbon substrate activated carbon. It was assumed that, as long as 10% by weight of the

carbon filter system was the acid, the new carbon system would function just as the carbon beads

do. It was also assumed that the theoretical weight of carbon needed to protect the catalyst in

diffusion would also protect the catalyst in the air purifier.

The last assumption was that the CO filter system (carbon and carbon monoxide) needed

to be changed on a one year basis along with the HEPA filter. This adds to its marketability

because the consumer would not be inconvenienced with having to replace the CO filter more

often than the HEPA.


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Summary of Final Design (overview of how it works)

Overview

Figure 3: Final Filter Design (Carbon & Catalyst)

Figure 4: Sandwich Design of Filter

inchActivatedCarbon

inch

ActivatedCarbon

inchCatalystFilter


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Figure 5: CO Filter implementation into IQ Air

Carbon Filter

Description of how it worksThe carbon filter is a protection for the catalyst that converts CO to CO 2. It was essential

in the design ensure the catalyst filter lasts for as long as the HEPA filter. The filter is thicker on

the air inlet to the air purifier because most of the VOCs that will damage the catalyst will be

introduced through this inlet. Also since the IQ air isnt completely air tight, and some back flow

does occur, a layer of carbon was added to the top, creating a sandwich design, in order to fully

protect the catalyst. The activated carbon works by scrubbing the VOCs out of the air. This in

effect kills the VOCs that would damage the catalyst and allows for normal operation of the

catalyst.


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Justification of your design decisionsAt first the carbon beads were the front-runners for the final design choice because they

were verified to work to protect the catalyst against harmful VOCs in the air. However, upon

completing the flow characterization shown in figure 6, it was apparent that the activated carbon

beads werent a viable option due to a huge pressure drop that would prevent air flow through

the IQ air. The second method, the carbon fabric, was ruled out because it not only showed

approximately twice the pressure drop of the felt, but it was discovered that woven fabric is

notoriously difficult to coat in phosphoric acid. Based upon these findings, and the knowledge

that carbon felt is used in industry in some air purifiers, the carbon felt was coated in phosphoric

acid, and used in the final design.

Carbon Options (flow characteristics)

0

0.5

1

1.5

2

2.5

0 200 400 600 800 1000 1200 1400 1600

Flow Speed (ft/min)

S t a t i c

P r e s s u r e

D r o p

( i n . w

a t e r )

0.25" Carbon felt

Carbon Weave

.5" Carbon Beads

.25" Carbon Beads

Figure 6: Air Flow Characteristics of each type of Carbon System


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Purchased engineering components and selection justification

The carbon beads were given to the group by Quantum. An ample supply of beads was

given to the group in order to test several thicknesses and configurations. When it was

discovered the beads werent a viable choice for our design the carbon felt and fabric was

ordered.

The carbon felt was ordered because one of the test purifiers employed the use of a felt

like material, and therefore it had been proven porous enough to work in airflow situations. It

showed the least amount of slow restriction as well as pressure drop of all three candidates, and

consequently was a top candidate to have coated in acid and tested.

The fabric was donated from Calgon Carbon Inc. It was postulated that since the carbon

fibers had a higher surface area than the felt, it might be a more effective method to scrub the

VOCs from the air.

Analysis used for sizing and design

In order to determine the thickness of felt needed in the final design the following

assumptions were made:

The average household has a background ammonia level of 40 ppbh (parts-per-billion-

hour). Second, in order to determine the amount of carbon needed to protect the catalyst,

it was assumed that the carbon would need to absorb all the ammonia over the course of a

year in a 2000 ft3

room. The last piece of the puzzle was the exact number amount of

phosphoric acid needed to completely neutralize the ammonia in the air. Therefore it was

assumed that the phosphoric acid completely reacts with the ammonia.

First the dosage was calculated:


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340 24 365 350 .262 ammoniag ppb day ppmhr

hr day year year m =

Second, knowing that the desired room size is 2000 ft 3 (56.6 m 3) the total mass of ammonia for

one year is calculated to be 14.838g. Lastly, knowing the molar masses of phosphoric acid andammonia as well as the complete reaction ratio of 3 mol ammonia : 1 mol phosphoric acid, it was

calculated that 28.5g of phosphoric acid were needed to protect the catalyst for one year.

Finally, careful measurements were taken of the weight pre and post activation. It was

found that a piece of activated carbon cloth contained 12g of phosphoric acid. From this data

the amount of phosphoric acid per inch was found to be approximately 53g. Thus, the final

theoretical thickness needed to protect the catalyst for one year is approximately 1/2 inch.

As stated previously a sandwich design was needed. And since more ammonia would be

taken in through the air inlet side, 1/4 inches of the felt was used on the inlet side and 1/4inch

was used on the air exit side of the filter.

Catalyst Filter

Figure 7:Main body of Catalyst Filter before filling with catalyst


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Figure 8: Complete catalyst filter before top is attached

Description of how it works

The final design for the catalyst filter mimics the particle filter that was being replaced.

It has the same footprint and checkerboard design as the particle filter. It has 16 -2 inch

squares equaling a flow area of .8 ft 2. A layer of nylon mesh is attached to the bottom of the main

body of the filter, shown in Figure 7. Each square is then filled with the catalyst beads and

clamped down at the top with another sheet of nylon mesh as shown in Figure 8. A small strip of

hot glue is added to the center bar to ensure a proper seal of each square. Subsequently it is all

held together with 4 threaded brass dowels to assure there is no leakage from the sides of the

filter.

Justification of your design decisions The filter was made with the same foot print as the pre-filter because it needed to not

only fit in the IQ air, but also it needed to maintain a seal such that air could only flow through

the catalyst and not around the filter. This seal ensures that all the air passes over the catalyst

beads, and thus, can be converted to carbon dioxide. Another major design constraint was

material compatibility with the catalyst. For this reason, nylon was chosen as the screen material

to be in intimate contact with the catalyst. Nylon was specifically chosen because it was proven


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to be compatible with the catalyst, and it is available in many different forms, including a mesh

material ideal for airflow, shown in Figure 9 .

Figure 9:Nylon Mesh with pore size


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Figure 10: Pressure Drop vs. Thickness

Figure 11: CO Reduction vs. Time for all thicknesses


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Figure 10 shows the pressure drop as a function of thickness for 3 fan settings. It shows

that at inch for speed 3 and 6 there is a significant increase in pressure drop across the filter,

which correlates to a significant reduction in flow rate, shown in comparison to a filter thickness

of one inch in Figure 12 . In Figure 11 a dismal 2-minute difference was observed between and

1-inch filter thicknesses while Figure 12 shows nearly a 50% reduction in airflow if the filter size

is increased to 1 inch.Thus, as a result of this testing, inch was decidedly the optimal thickness

for our air filter.

Figure 12: Pressure Drop vs. Flow Speed for and 1 inch

Purchased engineering components and selection justificationThe nylon was chosen due to material compatibility and availability. It was chosen with a

pour size less than 1mm because it was known that the minimum catalyst bead size is 1mm. Thus

when air is flowing through the filter, the catalyst beads stay in the filter and dont damage the

air purifier. Acrylic was purchased/donated from Chris Cassidy. Acrylic was chosen because it

was readily available, and was able to be cut on the lasercamm. This allowed the group to


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quickly test the effect of thickness on flow/pressure drop as well as on CO reduction. The last

purchase for the design was glue for a hot glue gun. Surprisingly hot glue is fully compatible

with the catalyst and forms and excellent bond between the nylon screen and the acrylic.

Analysis used for sizing and designA careful measurement was taken of the particle filter before design was made in Solid

Works. This was to ensure the proper fit of the filter into the IQ air. Next a barrage of CO

concentrations reduction tests were performed to determine the dependence on clean time on

thickness of catalyst, shown in Figure 11 . Comparing this data to the flow speed/pressure drop

data, the optimal combination of flow speed and carbon monoxide reduction was determined to

be inch.


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Analysis of Performance

Air Flow

AssumptionsThe IQ Air contains a centrifugal backward curved fan. This fan has a characteristic

performance curve that relates the static pressure drop ( sP ) to a given flow rate (Q) (Figure 14).

We obtained the fans specification sheet and used the reported curve.

We have assumed that the density of air does not change as it passes through the IQ Air.

We have also assumed that the low levels of CO and ammonia/VOC concentration do not affect

the properties of air at STP.

Every Air purifier on the market reports a flow rate (at each operation speed) in its

product specifications. As far as HEPA filters are concerned, the air flow through the fan is

indicative of the time to clean small particles, so as maintaining flow rate may not be as

important for the purposes of this project, it is still fairly important to the industry.

Analytical Methods UsedEvery apparatus that is subject to the flow system, such as screens and pre-existing

HEPA filters have a characteristic flow velocity vs. pressure drop curve. Every medium, such as

felt, carbon beads, or catalyst beads, has a characteristic curve as well (per unit thickness). All of

these curves must be experimentally determined and modeled.

The flow rate of the final design can be predicted by directly adding each components

pressure drop curve, yielding a system resistance curve. Wherever the system resistance curve

(flow rate vs. pressure drop) intersects the fan performance curve is more or less how the air

purifiers flow will perform.


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Darcys law describes flow characteristics through a porous medium, given a laminar

flow, i.e. with a Reynolds number sufficiently low.

However, problems arise when trying to characterize a systems Reynolds number, first

because the characteristic length is different for each medium (nylon mesh- 1mm opening,

carbon felt- O(.01mm) , catalyst beads- O(.1mm) ), and second because the velocity of the air is

changing through each medium, depending on that mediums porosity.

Darcys law states that in a laminar flow, the pressure drop through a porous medium is

directly proportional to the flow rate.

Since our flow system may not be laminar everywhere, we used a modified version of Darcys

Law called the Forchheimer equation. This equation is a second order polynomial, relating

pressure drop to Flow Velocity, and applies to higher flow rates. This is the flow model that was

universally used because there is no harm in having a V 2 term in the equation. Even if the V 2 term

is superfluous then its coefficient will be very small, having a negligible effect on our model:

=kinematic viscosity Q = flow rate

= permeability A = area of cross section

= geometric constant L = Length (thickness) of medium

= fluid density

The unknown values can be found using tabled values of and for ambient air at STP.

We did not bother extracting these values (unimportant for our purposes) because the combined


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coefficients are found using a second order polynomial regression. We have also normalized the

Velocity to our purifier, which has a 0.80 ft 3 through area. That made curves in terms of air flow

Q and Q2.

Analytical Results

Pressure Drop Curves of Materials

y = 0.00000129x 2 + 0.00208620xR2 = 0.98588545

y = 0.00000120x 2 + 0.00125582xR2 = 0.98848744

y = 0.00000087x 2 + 0.00084720xR2 = 0.97112618

y = 0.00000215x 2 + 0.00274777xR2 = 0.97784646

y = 0.00000340x 2 + 0.00134032xR2 = 0.99135291

y = 0.00000720x 2 + 0.00154800xR2 = 0.98553498

y = 0.00000037x 2 - 0.00000037xR2 = 0.99859931

0

0.5

1

1.5

2

2.5

0 200 400 600 800 1000 1200 1400Air Flow (cfm)

P r e s s u r e

D r o p

( i n c

h e s w

a t e r )

3/4" Carbon Felt1/2" Carbon Felt1/4" Carbon Felt1" Carbon Felt1/4" Catalyst1/2" Catalyst1mm Nylon Mesh

Figure 13: Characteristic flow curves for various mediums

Table II: 2nd order polynomial regression coefficients

material Q squaredterm Q term

Nylon 1mm 0.00000037 0.00000037Carbon Felt 0.25" 0.00000087 0.0008472Carbon Felt 0.50" 0.0000012 0.00125582

Carbon Felt 0.75" 0.00000129 0.0020862Carbon Felt 1.00" 0.00000215 0.00274777Catalyst 0.25" 0.0000034 0.00134032Catalyst 0.5" 0.0000072 0.001548


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The next step of this analysis was to add the coefficients of every medium in the final

design. The final design includes 2 layers of Nylon (1mm), Catalyst Beads (0.75), and Carbon

Felt 0.50, as well as the Hyper-HEPA filter. As we do not have data for the Hyper-HEPA filter,

it will be omitted from this analysis.

Adding all of these components curves yields the system resistance curve

( ) ( )20.00001254 0.00414488P Q Q = +

Laying that curve on the fan performance curve showed the intersection at final performance.

IQair Pressure Drop

0

0.5

1

1.5

2

2.5

3

3.5

0 100 200 300 400 500 600 700 800 900Air Flow (CFM)

P r e s s u r e

D r o p

( i n

H 2 0 )

IQair: Fan Parformance CurveFinal System Flow

Figure 14: Indicates final configuration performs at about 250 cfm

Note: inclusion of the hyper-HEPA filters pressure drop will push the system resistance curveup, causing an earlier intersection with the fan performance curve. That leads, as expected, to alower flow rate .


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Analysis of Performance

Catalyst Performance There were two methods used to develop models that describe the behavior of our

catalyst configuration. The first method was purely empirical, utilizing regression analyses on

test data. The second method had an analytical basis, building a model from the mass

conservation equation. Both models are of a similar form.

Method 1: Empirical Model

AssumptionsThe purpose of our CO concentration tests was to characterize the behavior of the

catalyst. The experimental variables included fan speed, catalyst volume, and room volume.

However, our test chamber was only 39.5 ft 3. Our model attempts to extrapolate this data

by a factor of about 50- applying to a room that is 2000 ft 3. For this model to apply at larger

scales, we must assume instantaneous fluid mixture and diffusion throughout the room.

Through these tests, weve discovered that the catalysts behavior is independent of fan

speed. Though there might be an air flow that is optimum, the benefit is so slight that we feel

justified in ignoring the variable of fan speed.

Also, our catalysts chemical reaction is very complex. There is a warm up period that

takes place after the catalyst has been inactive for any period. If the catalyst has been inactive

over night, then the warm up period is an entire test. However, it was observed that even when

the catalyst was inactive between tests it still took a few seconds for the catalyst to kick into high

gear. In these cases the warm up period looks very much like a transient response. Another

source of transient behavior is the time it takes for the fan to achieve full power/flow as well as


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the time it takes to establish an air flow throughout the room. Our model omits warm up runs,

but doesnt omit small transient response. The model is built as if the steady state is already

occurring at t=0.

CO Reduction vs. Time

0

5

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35time [min]

C O c o n c e n t r a t i o n [ p p m ]

all speeds

all speeds

all speeds

all speeds

all speeds

Figure 15: Plot shows that fan speed is not much of a factor

CO Concentration v. Time- 0.75" Catalyst, 40 ft 3 chamber

0

5

10

15

20

25

30

35

0 1 2 3 4 5 6 7 8 9 1 0

1 1

1 2

1 3

1 4

1 5

1 6

1 7

1 8

1 9

2 0

2 1

2 2

2 3

2 4

2 5

2 6

Time (min)

C o n c e n

t r a

t i o n

( p p m

)

Warm Up Run 1

Warm Up Run 2

Valid Test 1

Valid Test 2

Valid Test 3

Figure 16: Warm up runs & test runs


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Analytical Methods UsedThere is a complex theoretical basis for the performance of our catalyst. The chemistry

involved in that theory is beyond the scope of this project. In lieu of a strictly theoretical basis,

we first observed test results and then backed out reasonable theory, which would imply such

results. From this post hoc theory we have built a model that characterizes the catalyst

performance. Using regression analysis, we have tuned the parameters to best fit all of our test

data. Once the model was tuned, we could use it to predict performance for configurations (of

room size and catalyst volume) that extrapolate the test results.

The test data shows a very clean exponential decay of CO concentration in time. On an

instantaneous level, the chemistry follows a first order rate equation:

[ ][ ]

d COr k CO

dt = =

where:

[ ] concentration of carbon monoxiderate constant

CO

k

=

=

The solution to this differential equation is of the form:

[ ]( ) kt CO t a e =

There are 2 coefficients in each curve fit. Once we apply initial conditions to the

exponential decay curve, we see that the first coefficient a must be the initial concentration

(C o).The second coefficient is the reaction rate coefficient.

The reaction rate coefficient varied, as was observed, due to changes in catalyst thickness

and changes in room volume. As expected, the rate constant k went down with increasing room

size. That led to a longer clean time. On the other hand, the rate constant k went up with thicker

filter configurations. This led to a quicker clean time, as there was simply a higher volume of

catalyst present in the filter.


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Analytical ResultsThe rate coefficient ( k) was split apart to reveal a dependence on Catalyst Volume ( c )

and Room Volume ( r ). Once the variables were extracted from the reaction rate coefficient k ,

we observed that it became more of a reaction rate constant b.

( )( )[ ]( )

xc

yr

bt

oCO t C e

=

where:

[CO] = carbon monoxide concentration= volume of catalyst= volume of room

parameter to be tunedparameter to be tunedisolated reaction rate constant

C initial concentration

time

c

r

o

x

y

b

t

=

=

=

=

=

The reaction coefficient (k) was plotted against the volume of catalyst ( c ), each time

raising the power of c to a different number ( x) (Error! Reference source not found. ). A

linear regression was applied to each value of x. The coefficient of determination (R2) was

recorded for each plot (Table III). Then the coefficient of determination (R2) was plotted against

power ( x) (Error! Reference source not found. ).


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y = 3.4529818xR2 = 0.9669569

0.00

0.10

0.20

0.30

0.40

0 0.025 0.05 0.075 0.1

Catalyst Volume^1.00

R e a c

t i o n

C o e

f f i c i e n

t

Figure 17: Example when x=1.00, yields R^2=0.9669569

Table III: R2 values for different regressions

(Vol. of Cat.)^x

Coefficient ofDetermination

(R^2 Value)

1 0.96695691.1 0.93327851.2 0.88902890.9 0.98749350.8 0.99189010.7 0.9767191

0.75 0.98698080.85 0.99191370.81 0.99227120.82 0.99246050.83 0.99246170.84 0.9922783


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Figure 18: Shows a peak correlation when x= 0.83

The same regression analysis was done with respect to room volume.

Effect of Volume change on Reaction rate

y = 16.680820xR2 = 0.985694

y = 11.004590xR2 = 0.973992

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.01 0.02 0.03 0.04 0.05 0.06

1/Volume

R e a c

t i o n

R a

t e

Volume^1.13

Volume^1

Figure 19:Examples when y=1.00, yields R^2=0.973992,when y=1.13 yields R2=0.985694


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Method 2: Analytical Solution Model Equation Section 1 Mass Balance of Carbon Monoxide

AssumptionsIn order to avoid the complications that arise from fluid mixture and CO diffusion

throughout the room, this model assumes instantaneous fluid mixture and diffusion throughout

the room.

The mass balance model is also built as if the steady state is already occurring at t=0 i.e.

there is no transient response time.

Analytical Methods UsedThis model has its basis in the conservation of mass equation. This model is built as

though there are two mass flows. One is leaving the room (at the rooms concentration), and the

other is entering the room (after filtering; at the reduced concentration). This is exactly what is

going on (as if they were in a direct loop), just a convenient way of thinking about it. The

volumetric flow rate, Q, is the same for both.

,C O inm ,C O o ut m

The differential form of the mass balance equation is

, , ,CO room CO in CO out d

M m mdt

= (1.1)

MCO,room


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and

( ), [ ] [ ]CO room in out d

M Q CO COdt

= (1.2)

because

[ ] [ ]CO CO M M s m

CO m CO Qs Q

= = = .

(1.3)

Lets look at what is happening through a cross section of the catalyst filter.

The main assumption here is that the concentration change is directly proportional to how

much time the air spent in contact with the catalyst. This assumption departs from reality, but

may allow for a convenient collection of variables (in reality, the concentration follows the first

order chemical rate equation. An analysis using that method is shown after this one). Our

assumption is,

2 1C k tim e C = (1.4)

but,

.

Dist d Velocity t

Time v= =

.(1.5)

So (1.4) with (1.5) ,

2 1d

C k C v

= (1.6)

Where 0


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C1 is the concentration leaving the room, i.e. [CO] out .

and C 2 is the concentration entering the room, i.e. [CO] in, (1.6) becomes

[ ] [ ]in out d

CO k COv

=

.

(1.7)

Putting (1.7)into the mass balance (1.2) and factoring gives

, [ ] [ ] 1 [ ] [ ]CO room out out out out d d d d

M Q k CO CO Q k CO Q k Q COdt v v v

= = =

(1.8)

and since

Q A re a V e l= , (1.9)

( ), [ ] [ ]CO room out out d d M A v k Q CO A k d Q COdt v = = .

(1.10)

Now we see that

ca t ca t ca t A re a D ep th = (1.11)

which yields

( ), [ ]CO room cat out d

M k Q COdt

=

.(1.12)

We would like to see (1.12) in terms of only concentration so,

, [ ]C O roo m room room M C O= (1.13)

and the chain rule applies.

( ), [ ] [ ] [ ]CO room room room r r r r d d d d

M CO CO COdt dt dt dt

= = + (1.14)

Since the room isnt changing volume

0r d dt = (1.15)


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and using initial conditions

( )[ ] 0 oCO C = I.C. (1.25)

implies that

0oC e C = . (1.26)

( )( )

[ ]cat

r

k Q t

oCO t C e

= (1.27)

The units of a rate constant (k) for a first order reaction is 1/sec, so the units work out to be

dimensionless.

note: (1.27) This is a slightly simplified model of Carbon Monoxide concentration through time.

The model developed below is a slightly more vigorous derivation.

In Depth Model Using Reaction Rate LawNow we can take a closer look at what ishappening through a cross section of the catalyst

filter.

The concentration follows the first order rate equation during the time it is encountering the

catalyst (of course, this is also an assumption. This is the part of the analysis that would change

according to the real behavior of the chemical reaction)

C1, v C2, v

d


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Equation Chapter (Next) Section 2 [ ] [ ]d COr k COdt

= =

.(2.1)

Separating variables gives

[ ][ ]d CO kdt CO= (2.2)

and integrating,

ln[ ]d CO kdt = (2.3)

ln [ ]C O kt c= + (2.4)

Solving for [CO],

[ ]( ) kt CO t c e = (2.5)

Applying boundary conditions:

0 1[ ] t C O C = = B.C. 1(2.6)

2[ ]t d vCO C = = B.C. 2(2.7)

From (2.6) we see that

0 1[ ](0)CO c e c C = = = , (2.8)

and from (2.7)

1 2[ ]( )k d

vd CO C e C v

= = (2.9)

So the relation that can be used in the mass balance is

2 1

k d vC C e

= (2.10)

instead of(1.6): ( 2 1d

C k C v

= )

Again, C 1 is [CO] out and C 2 is [CO] in, so (2.10) becomes

[ ] [ ]k d

vin out CO CO e

= (2.11)


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into the mass balance (1.2) :

, [ ] [ ] 1 [ ]k d k d

v vCO room out out out

d M Q e CO CO Q e CO

dt

= =

(2.12)

equations (1.13) to (1.16) still apply, so

[ ] 1 [ ]k d

vr r out

d CO Q e CO

dt

=

(2.13)

Equation (1.18) still applies. The model becomes

1[ ] [ ]

k d v

r

d eCO Q CO

dt

=

.

(2.14)

We can separate variables for the solution to this differential equation:

[ ] 1[ ]

k d v

r

d CO eQ dt

CO

=

(2.15)

and integrating;

[ ] 1[ ]

k d v

r

d CO eQ dt

CO

=

1ln[ ]

k d v

r

eCO Q t C

= +


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and solving for [CO] gives the general form solution;

1 1

[ ]

k d k d v v

r r

e eQ t C Q t

CO e C e

+ = = (2.16)

initial conditions apply as in (1.25) and (1.26);

( )[ ] 0 oCO C = means 0 oC e C = so C=C o

The complete model is now:

1

[ ]( )

k d v

r

eQ t

oCO t C e

= (2.17)

This is a more realistic model of carbon monoxide concentration through time. We could go

deeper into how face centered cubic packing of the catalyst creates a porosity that increases the

velocity of the air through the medium by a factor. The catalyst beads have a tolerance ranging

from 1mm-2mm. So the FCC packing factor doesnt really apply. What needs to be done to find

velocity through the catalyst is divide the bulk volume by the empty space volume;

. .

bcat b

b w d

v v

=

(2.18)

Where,

. .

velocity through catalyst

bulk velocity through system (measurable)bulk volume of catalyst

water displacement volume

cat

b

b

w d

v

v

We could also go into how bead size affects reaction rate because of the different surface

area and characteristic length, but these changes of approach would just be absorbed in the k

value anyways.


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The most important part of this analysis is the inverse volume relationship that we have

found. Again, this is so important because we are extrapolating the volume of our test data by a

factor of 50.

Analytical ResultsAn equivalent form of (2.17) is,

1

[ ]( )

k cQ

r

eQ t

oC O t C e

=

Applying (2.18) to our test data indicated that k = 114 (1/min).

Our final designs catalyst volume is c = 0.050 (ft 3),

And the flow rate is predicted to be Q = 250 (cfm).

The room size is r = 2000 (ft3).

Designed to filter out an initial concentration of oC = 30 (ppm).

To a much lower concentration of [ CO ]= 2 (ppm).

Inputting these parameters into (2.17) and solving for t (min) yields a

clean time of 16.02 hours .

Description of Fabrication Process 1. Cut design out of and inch acrylic using the Lasercamm (cut 4 of the inch

skeleton pieces and 1 inch pieces)

2. On one side of a inch piece attach a sheet of nylon mesh (pour size


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3. Attach the similar inch filter skeleton using hot glue to one of the pieces on the

opposite side of the nylon mesh, being sure to put the hot glue around the perimeter and

in the center of the filter; this will ensure the catalyst beads stay in each small square and

cannon migrate between the and inch piece of acrylic.

4. At this point the layers (from the bottom up) should be nylon, inch acrylic piece,

inch acrylic piece

5. Fill the filter with catalyst beads and scrape off the excess until each square is filled and

level with the top acrylic piece (show in Figure 21)

Figure 21: Fill level of Catalyst Filter

6. Next the remaining inch acrylic/nylon piece, nylon side down to the top of the inch

piece using hot glue. From the side the filter should resemble Figure 22

Bottom

Figure 22: Side view of catalyst filter


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7. The next step involves cutting 4 inch pieces of activated carbon felt into 13 by 13 inch

squares.

8. Three pieces of this felt were then placed one on top of another on the bottom of the

catalyst filter then clamped down using a inch acrylic filter skeleton piece and 4 8-32

bolts.

9. Finally the remaining piece of activated carbon was placed on the top of the catalystfilter, and clamped down using the final inch filter skeleton piece using 4 8-32 bolts. A

schematic of the final configuration is shown in Figure 23 .

Figure 23: (Side View) Schematic of Final Filter- airflow from bottom to top


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Testing/Evaluation

Test Methods The testing of the filter design consisted of two steps. First a flow test was conducted

using a handheld anemometer. The airflow speed was measured and then converted to a

volumetric flow rate knowing that the flow area was equal to .8ft 2. This reading was taken at

multiple points across the entire inlet area in order to get an average inlet flow. The pressure drop

across the filter was measured using an oil filled manometer that measured the pressure drop in

inches of water as shown in Figure 24. In order to achieve this measurement a small tube was

placed in the IQ air, and once the fan turned on the change in height of the manometer was

recorded. The same measurements were also taken for the nylon screen and various carbon

systems.

Figure 24:Oil Manometer used to measure pressure drop


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The time was recorded when the ppm dropped and was also recorded by the drager into

its internal memory. This test was repeated for catalyst thicknesses ranging from to 1.25

inches on three different fan speeds. This allowed the group to fully characterize the catalyst

performance in an air purifier, and thus systematically choosing the optimal thickness for the

purifier.

The next phase of testing of testing involved sectioning off portions of the test volume in

order to derive an analytical model to predict the filters performance in a 2000 ft 3 room. Carbon

monoxide reduction testing was performed at and test chamber volume (825 and 550 Liters

respectively). The volume was sectioned off using a plastic sheet and duct tape; this is shown inFigure 27 and Figure 28.

Figure 27: volume test chamber construction Figure 28: volume test set up

In order to ensure the validity of our data a separate drager was placed into the test chamber on

the side that was not exposed to carbon monoxide in order to detect any leakage that might have

occurred, which is depicted in Figure 29. After this construction normal CO reduction tests were

performed as described above.


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Figure 29: -volume test chamber with extra drager

Evaluation of the Final design

Using the test methods described above, the final design was subjected to carbon

monoxide reduction tests. The results of which are shown in Figure 30 .

Figure 30: CO reduction vs. time for Final Design


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Comparison of prototype to production design

In the teams prototype, simplicity of design and the ability to quickly modify the catalyst

thickness was essential for testing purposes. Both these designs must be able to fit in the space

that will be utilized in the IQ Air. The current space in the IQ Air is filled with a pre filter. This

pre-filters dimensional footprint was the basis of the design for the prototype and the final

design. To achieve this acrylic sheeting of multiple thicknesses were utilized in manufacturing

multiple thin layers. These layers were utilized by stacking them to provide varying thicknesses

to contain the catalyst. These different catalyst thicknesses were placed in the IQ Air for

efficiency testing. The acrylic pieces were manufactured with 16 through holes to provide space

to place the catalyst. To close the ends of the acrylic pieces nylon mesh was used. This mesh was

adhered to the acrylic with hot glue, since hot glue is one of the only adhesives that is approved

for use with the catalyst. To hold all the layers of acrylic together through holes were place in the

acrylic to enable threaded rod to be placed through. This threaded rod was then secured with

washers and nuts that essentially sandwiched all the panels together.

In the final design a mass manufacturing approach was used in the design of the catalyst

containment system. In this approach the use of easily manufactured structures and cheap

material costs were the optimizing factors. To achieve the teams optimizing factors, the use of

cardstock for the structural portion of the catalyst was chosen. Cardstock is easily manipulated

and is a cheap material. This is a common material used in the manufacturing of common air

filter cartridges. To close the gaps at the end of the catalyst containment system the nylon mesh

from the prototype design was carried over to the final design. It was observed that this material

was very effective and came at a low cost. The mesh cardstock interface would be secured using

the same hot glue from the prototype design.


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Cost Analysis/ProjectionsThe majority of the cost in a product like this is the catalyst. There is a lot of labor

involved in making them as well as not a current way to mass-produce them. Also, there are not

current activated carbon felts that are ready to be used out of the bag. Quantum dips each piece

of felt in a phosphoric acid bath.

Table V: Projected Cost for production design

Material/ Machinery Initial cost Cost per partCarbon Felt N/A $2.50

Fiberboard stock N/A $0.17

Nylon mesh N/A $0.58Hot glue N/A $0.01

Catalyst beads N/A $1.40Fiberboard cutter/former/assembly minimum $20,000 $3

Total cost $20,000 $7.99

Safety/Impact on SocietyThe impact on society of our project is quite positive. It can reduce a large amount of work

and home-related illnesses. There has not been enough research released to the public regarding

long-term carbon monoxide, which is unfortunate because there are some real risks. Low-level

exposure of carbon monoxide over a long period of time can cause headaches, muscle atrophy,

and mild death [8].

With all air purifiers now having the capability of removing a majority of the airborne

chemicals in the air, this product would have an immediate positive impact on all who utilize it

by reducing the volatile organic compounds in the air as well as harmful carbon monoxide.


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Conclusion/RecommendationsThe group definitely considers this project to be a success. We have proven the viability

of implementing this technology into an air purifier. We have described our method and design

for building the CO CO2 filter. We have also developed a mathematical model that fully

describes how the purifier will perform; both in air flow and CO concentration.

The analytical model is a good starting point for determining the clean time for an array

of parameters, including room size, fan speed +/or power, flow rate, initial concentration,

catalyst volume, and carbon felt thickness.

The groups main recommendations are in regards to ammonia and VOC tests. We did

not have the proper facilities or time allotment to extensively test ammonia, but such tests would

have given us a better idea of how to protect our catalyst. The carbon calculations that we have

performed (and ultimately used in the final design) were an extrapolation based on diffusion test

data. We do not know how well a diffusion situation correlates to a forced airflow situation.

Another recommendation is to vary catalyst bead size. A larger bead will allow more

airflow, though at the expense of CO CO2 effectiveness. If preserving airflow is a priority for

air purifier manufacturers, then our final design can be adjusted accordingly.

There can also be a sensor, mounted on the filter itself that indicates when the filter is no

longer functional. The consumer would only have to pull out the filter and look at the sensor to

see if the filter is still functioning. This would be relatively easy to install, considering these

sensors already exist.

AcknowledgmentsWe would like to thank everyone that helped in completing the CO CO2 project.


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To start off we would like to thank the staff at Quantum Group Inc.:

Adam Ariely -Supervising Mechanical Engineer

Michelle Oum-Lead Chemical Engineer

Eddie Tarango-mechanical Engineer

Secondly we would like to thank the staff and professors of University of California San Diego:

Jerry Tustaniwskyj-Lead Professor

Tom Chalfant-Machine shop supervisor

Dave Lischer-Student project supervisor

Sara Marsha- Teachers assistant

Ron Keets-Technical sales representative at SKC Global

We would like to thank anyone else we may have forgotten.

References[1] http://www.air-purifier-power.com/cadr.html ][2] http://www.iqair.us/sars.html [3] http://www.allergyconsumerreview.com/air-purifiers-sars.html [4] http://www.airpure.com/IQAir-sars.html [5] http://en.wikipedia.org/wiki/Porosity [6] http://en.wikipedia.org/wiki/Mass_balance [7] http://en.wikipedia.org/wiki/Rate_law [8] Environmental Protection Agency. Carbon Monoxide, Basic Information. Retrieved onMay 6, 2008 http://www.epa.gov/iaq/co.html#Levels%20in%20Homes


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Appendix

Project Management

During the course of this project, the group members have wore many hats. The initial hats were

researchers and rough estimators. Then technical callers, when questions needed to be answered

by companies who make products of interest to the group. Then fabricating was done, which

then followed into testers and into data analyzers and technicalwriters, web designers, project

managers. It is accurate to say every aspect of the project has been a complete group effort.

Table VI: Team Task Descriptions

TaskDescription Person Percentage Description

Researchgeneral airpurifiers Brian 25%

Familiarize with current market modelsand features

Isaiah 25%Neal 25%Sean 25%

AnalyticalCalculations Brian 25%

Determining theoretical flow,concentration, and other importantcharacteristics of the project


CAD andSketches Brian 25%

Early designs and final designs


Parts andMaterials Brian 25%

Researching, contacting supplier andsending order info to Quantum

Isaiah 25%Neal 25%


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Sean 25%

Purchasing Brian 25%Buying stuff at Home Depot, IndustrialMetal Supply and wherever

Isaiah 25%

Neal 25%Sean 25%

Initial FlowTesting Brian 25%

Checking actual flow values with statedflow from manufacturer's on air purifiers


PrototypeBuilding Brian 25%

Making early filter parts to get rough ideaof how catalyst will work


ReportWriting Brian 25%

Writing the report


Web DesignBrian 25%

Designing the website took a group effortfor feedback


Presentations Brian 25%

Making slides and knowing what to say


WeeklyUpdates Brian 25%

Keeping our sponsors and professors upto date every week


MeetingTimes Brian 25%

Checking each others schedules to makesure the times worked


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Weekly

SponsorMeetings Brian 25%

Making sure everyone could come and if

not, fill them on to keep them up to speed


Design Drawings:

Figure 31: Initial box design for CO test chamber


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Figure 32: Initial sketch of how flow chamber would look

Table VII: Budget

Qty Date VendorManufact

urer Part #Descripti

on

UnitPric

eShippi

ng TaxTotalPrice

2 4/7/08McMaster-

Carr9318T

13

NylonMesh-.85mm 9 2.79 20.79

2 4/7/08McMaster-

Carr9318T

44

NylonMesh-.5mm 9 2.79 20.79

4 5/7/08McMaster-

CarrCarbonfelt- 1/4" 7 2.17 30.17

4 5/7/08McMaster-

CarrCarbonfelt -1/8" 7 2.17 30.17

1

IndustrialMetal

Supply

SteelDiamond

Mesh 25 0 1.9375 26.94

4

IndustrialMetal

SupplyAluminum

blocks 1.25 0 0.3875 5.39


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CO to CO2 Filter Implementation

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