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Engineering 100W Section 13!

Student: Gavin Chen!

Dr. Lin Zou!

San Jose State University, Charles W. Davidson College of Engineering!

Date of submission: 06 May 2016! !

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Table of Contents!1 Abstract…………………………………………………………………………………. 03!2 Introduction ……………………………………………………………………………...04!3 The Big Three……………................................................................................................05! 3.1 Introduction! 3.2 Misconceptions about recycling ! 3.3 Upcycling ! 3.4 Comparison: Upcycling Vs. recycling ! 3.5 The Last Resort: Downcycling ! 3.6 Conclusion !4 Coffee Grounds for Cosmetics…………………...............................................................10!

4.1 Introduction 4.2 Possibility as a Sun Filter!4.3 Increasing the Rate Growth of Hair Follicle!4.4 Protection Against Skin Cancer!4.5 Conclusion!

5 Bio Oil………………........................................................................................................16!5.1 Introduction !5.2 Experiment Procedure ! 5.2.1 Materials! 5.2.2 Hydrothermal Liquefaction Procedure!5.3 Characterization of Bio-Oil !5.4 Conclusion !

6 Tannins Extract …………….............................................................................................20!6.1 Introduction !6.2 Production Method !6.3 Results of Acid-Base Extraction Experiment !6.4 Conclusion !

7 Energy-Spent Coffee Ground Fuel Cell ……………........................................................23!7.1 Introduction !7.2 Concepts of the Experiment !7.3 Data and Discoveries !7.4 Conclusion !

8 Grounds Used as a Raw Product ……………...................................................................26! 8.1 Introduction !

8.2 Natural Properties of Coffee Grounds !8.3 Household Applications !8.4 Gardening Applications !8.5 Conclusion !

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9 Overall Cost Analysis ……………...................................................................................31!10 Final Conclusion and Recommendations ..........................................................................33!11 Bibliography .....................................................................................................................36!!!

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1 Abstract!!

People drink coffee almost everyday and do not realize how much waste coffee negatively affects the environment. By upcycling waste coffee beans in the form of cosmetics, biomass, or even raw grounds, the Starbucks Corp. can reduce its negative impact on the environment. By turning coffee grounds into something more usable and environmentally friendly, Starbucks Corp. would be able to maximize their total revenue in a long term. In addition, these scientific findings we found regarding the usage of coffee grounds, will help further the end of life cycle development for Starbucks Corp. !! !

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2 Introduction!

The Starbucks Corporation is a commercial giant in the beverage industry. It handles

everything from resource sourcing to manufacturing to distribution. The Starbucks Corporation

is proud to announce its continuous effort to approach a complete sourcing of coffee beans

through ethical practices. However, Starbucks Corporation does not manage its main product’s

end of life cycle sufficiently. Although the coffee cups may be a major source of waste, that

should be handled by the consumers. In 2014, Starbucks Corporation chewed through over 208

million tons of coffee beans. The Starbucks Corporation may have the Grounds for Your Garden,

a program in place to manage portions of their share of waste grounds, but it is not a very

successful program when considering the impact it holds with the community. The vast majority

of Starbucks Corporation’s used coffee beans were sent to the landfills. In 2015, the human

population collectively sent a verified whopping 142 million tons of used coffee beans directly to

landfills (Yang). This environmental proposal demands the Starbucks Corporation must manage

the end of life cycle of their coffee beans. This is no small feat. To get Starbucks Corporation

started with a few methods of coffee waste management, we have left several suggestions.

Jordan Lum has been tasked with effectively explaining the most useful subgroup of recycling,

upcycling. Once upcycling has been established, Dennys Sudarma, Gavin Chen, and Justin Poon

will introduce multiple methods of upcycling coffee waste in various fields, such as cosmetics,

biomass, and low reprocessed products, respectively. Of course, why would Starbucks even

consider such an act if these proposals would cost them money? Justin Poon has conducted a

thorough cost analysis of these suggestions.!!

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3 The Big Three! 3.1 Introduction!

Moving past conventional disposal techniques, coffee grounds can be refined and reused to serve

a better purpose than filling up landfills through alternate methods. These methods are as

follows and listed in the order of decreasing precedence, upcycling, recycling and downcycling.

Though all three methods are seen to be more sustainable than conventional disposal techniques,

our specific focus will be the incorporation of upcycling into the coffee EOL or end of life

lifecycle at Starbucks. When in comparison to traditional disposal and other sustainable

techniques, coffee grounds can be spent more efficiently via upcycling.!

3.2 Misconception about recycling!

When people think about sustainability, the first thing that probably comes to mind is reduce,

reuse and recycle. Through this day and age, there is still a big misconception about recycling,

tough recycling is better than sending items straight into a landfill, there is still much that can be

done. To further understand this major misconception, we first have to understand what

recycling is, according to the environmental protection agency, recycling is “the process of

collecting and processing materials that would otherwise be thrown away as trash and turning

them into new products of equal value”. Tough recycling is considered sustainable, a major flaw

with recycling is that the process does not follow a linear trend for all products or materials, in

layman terms, this means not all products are recycled equally. With a non-linear distribution,

more often than not, material quality and composition will fall short and forced to be discarded

or at best case downcycled. A rudimentary example of this is plastic bottles, most often these

bottles cannot be associated with anything that can be ingested due to the risk of things seeping

into the plastic. With our focus on Starbuck coffee grounds, the grounds fall in the special case

where recycling would prove to be null due to the nature that you would not want to recycle

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coffee grounds back into coffee grounds. Instead, you would want to convert the coffee grounds

into something of greater value, and this is where upcycling comes into play. !

3.3 Upcycling!

What is upcycling? According to the oxford dictionary, upcycling is defined as “reusing

(discarded objects or material) in such a way as to create a product of a higher quality or value

than the original”. With upcycling, no matter what products or materials you are dealing with, at

worst case scenario, a quadratic trend will follow. Upcycling incorporates new technologies,

techniques and a bit of creativity, proving an end product of greater value than your original

input. The environmental benefits of upcycling are mammoth, aside from minimizing the

volume of discarded materials and waste, which would otherwise be sent to landfills each year,

the production of new or raw materials are also reduced. With the decrease in production of new

or raw materials also comes a decrease in air pollution, water pollution and greenhouse gas

emission. For the scenario with Starbuck coffee grounds, a rudimentary example of this factor at

play would be the lower consumption of garbage bags needed. With upcycling, coffee grounds

can be repackaged in its original packaging and instead of being transported to a landfill, the

grounds can be distributed at the Starbucks location. When taking into account that in 2015,

Starbucks globally produced approximately 19.4 billion pounds of spent coffee grounds, with an

average american trash ranging from 13-16 gallons per bag, at best case scenario, that would be a

staggering 145 million 16 gallon trash bags used. From the example provided, it can also be

determined that aside from environmental benefits, Starbucks can also benefit financially as well,

with less cost. While the environmental and financial benefits are easily identifiable, the social

and personal benefits for both the designer/producer and the consumer are also enormous. In the

situation with coffee grounds at Starbucks, through upcycling, Starbucks will manage to increase

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Figure!4.4!

public relations by showing that not only does the company care about its coffee, but also the

environment as well. Lastly, through upcycling, personal benefits, for Starbucks may include,

being able to showcase unique pieces created from coffee grounds in their brick and mortar

stores and also the benefit of knowing the company as a whole is moving towards a more

sustainable future. !

3.4 Comparison: Upcycling Vs. Recycling!

When comparing recycling and upcycling, upcycling is

found to be the best route possible, as materials are used for

a higher purpose than what it was originally intended for.

The most oblivious difference between upcycling and

recycling is the fact that upcycling produces a product of

greater value than its original form, while recycling creates

a product of equal value. Though for Starbucks, upfront

profits from upcycling used coffee grounds would be null,

however public relations generated may lead to increase

sales. The second difference is that recycling faces a

downward sloping trend, the more times a material goes through the

process, the higher the likelihood for the material to degrade in quality or composition.

However, with upcycling, the process follows an upward sloping trend, the more times a material

or product goes through the process, the more refined it gets. For Starbuck, recycling used

coffee grounds would not be a logically sound idea, as more environmentally conscious and

effective options are available, such as upcycling. !

A study from Harvard University show that,!

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“Although the manufacturing of a product from recycled goods emits less air pollutants

and greenhouse gas emissions than making the same goods from raw resources, the

recycling and processing of recyclables still generates pollutants and emissions. This

includes the fuel burned by trucks collecting recyclables, as well as the energy and water

expended during processing.”!

Water consumption and pollutants from the recycling process is a huge concern for some, due to

sanitary reasons, recycling products usually require a large mixture of harsh chemicals to strip

impurities from the original product. With the large mixture of harsh chemicals, materials or

products must be thoroughly rinsed free of chemicals. While recycling entails the use of

precious water and harsh chemicals, upcycling is completely rids itself from the need of the two.

All upcycling uses is a bit of creativity, which of course is completely free and contain no harsh

contaminants. From a financial standpoint, upcycling creates an opportunity for profits, while

recycling may entail cost or miniscule profits. According to the National Institute of

Environmental Health Sciences, in San Jose, “it originally cost $28 to send a ton of waste to the

landfill while it cost $147 to recycle the same amount”. As you can see, from this generalized

guestimate, from a financial standpoint, there would be little to no incentive for Starbucks to

incorporate a program which will cost them more than five times their initial cost for waste

products. While recycling does prove to have a lot of downfalls when in comparison to

upcycling, financially and economically, the two still prove to be more sustainable that

downcycling. !

3.5 The Last Resort: Downcycling!

Moving past recycling and upcycling, downcycling is usually the byproduct of the former two,

and should only be incorporated as a last resort before disposal and transportation to traditional

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landfills. According to Merriam-Webster dictionary, downcycling is described as, “recycling

(something) in such a way that the resulting product is of a lower value than the original item”.

Although downcycling is sometimes better than traditional disposal methods, usually from a

financial and environmental aspect, downcycling does not make sense for most cases.

Downcycling can even prove to be worse than traditional disposal methods due to the fact that

during the downcycling process high quality items are consumed. These high quality items,

require a lot of energy and materials to produce and in return have a major impact financially and

environmentally. In the scenario at starbucks, from an observer's standpoint, due to the low-

level form which coffee grounds are presented, little to no downcycling would be available in a

cost effective manner and will more than likely be disposed of. !

3.6 Conclusion!

There are three main strategies for sustainability, downcycling, recycling, and upcycling.

Downcycling is an economically worthless and usually an environmentally destructive process,

while recycling and upcycling creates products, which tend to be more usable for future

purposes. Through our extensive comparison between recycling and upcycling, it is concluded

that used coffee grounds cannot be effectively recycled and it is recommended that Starbucks

Corporation upcycle it’s used coffee grounds instead. The upcycling process will prove to be

more efficient than all other available methods previously mentioned and will be further

examined in sections below.!

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4 Coffee Grounds for Cosmetics!4.1 Introduction!

Coffee grounds can be useful to many consumers in many ways. One way that attracts many

consumers out there, especially for females, is the contribution of coffee bean oil in relation to

cosmetic products. These products such as shampoo, body lotion, or cream are just some

examples among many other products that consumers use from coffee bean oil to improve their

appearance. Nonetheless, there is a way to obtain some of the coffee bean oil products without

directly buying the products from the store. That way is to get our hands dirty and naturally make

our own products from coffee grounds. However, the purpose of this findings regarding coffee

grounds is not to convince the consumers to buy or make coffee bean oil related products, but

rather to educate them about how a renewable product such as coffee ground can become useful

to our lives, especially in terms of cosmetics.!

4.2 Possibility as a Sun Filter!

Coffee bean oil, which can be extracted from coffee grounds, can be used to protect our skin

from the sunlight. To show that, we need to be familiar with the sun properties. If we look at the

spectrum of sunlight, we can see that the higher intensity of the sunlight occurs between two

hundred and fifty to six hundred nanometer. On the other hand, coffee bean oil has an absorption

of light in the range of two hundred and eighty to three hundred and twenty nanometer according

to Jean F. Grollier and Sophie Plessis on “Use of Coffee Bean Oil as a Sun Filter”. In addition,

they further make their own product to test the effectiveness of coffee oil bean by using the

compositions as follows: coffee bean oil, self-emulsifiable glycerol monostearate, sorbitan

monostearate polyoxyethyleneated with ethylene oxide, stearic acid, pure cetyl alcohol,

propylene glycol, lanolin, triethanolamine, methyl para-hydroxybenzoate, perfume, and water.

These compositions will produce a type of cream that is capable to protect skin due to its ability

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of maintaining a thin continuous layer across the surface of skin. According to J. Marto, one of

the authors of “The Green Generation of Sunscreens: Using Coffee Industrial Sub-products,” it is

possible to produce a sunscreen or a type of cream that only use a process of emulsification. The

form that of this type of sunscreen is called water-in-oil emulsions. This emulsion process will

contain about 35% of the coffee grounds by weight, which is acceptable by the safety standards.

This is the full explanation by J. Marto regarding the new way to produce a sunscreen:!

The purpose of this work was to assess the biological effects of using the oil fraction of spent coffee grounds extracted with supercritical CO2 and green coffee oil in the development of new generation of sunscreens with improved sun protection performance. The oil fractions were used to prepare w/o sunscreens involving a cold emulsification process, with purified water as disperse aqueous phase and TiO2 and ZnO particles as stabilizers. The sunscreens were characterized in terms of mechanical, rheological and skin adhesion properties. In addition, the in vitro and in vivo biological properties of the formulations were evaluated, including safety and sunscreen water resistance tests.!!The use of two types of solid particles proved to be useful in the developed formulations, ensuring a high SPF with UVB/A protection, conferred by TiO2 and ZnO, respectively. Moreover, the emulsion containing 35% w/w of the spent coffee grounds oil fraction presented promising characteristics in the improvement of water performance with a broad spectrum sun protection when compared to an emulsion containing 35% w/w of green coffee oil which improved the SPF in physical sunscreens. The formulations are industrial-scalable and suitable for topical use according to the rheological, mechanical and safety assessment. (2016)!!

Aside from the potential to make a sunscreen, in order to show the validity of these compositions

that are obtained from coffee ground, Xiaofeng Li, the author of “Energy Recovery Potential

Analysis of Spend Coffee Grounds Pyrolysis Product,” shows the list of compounds that are

obtainable from coffee grounds with a process of heat treatment.!

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Figure 2.1: Distribution of compounds from pyrolysis in coffee grounds.!

From the figure, the two most compounds that can be obtained from coffee grounds are linoleic

acid and palmitic acid. According to the cosmetic database of EWG’s Skin Deep, palmitic acid is

a good emollient ingredient in terms of body cream. There are definitely other skin protection

products that can be produced from the rest of the compounds listed on the table. Some

compounds may be harder to be extracted when compared to the other due to their chemical

bonds. However, with a method of pyrolysis, the chance in extracting a certain compound will

increase to the point that we are no longer need to worry about destroying other chemical

compounds in the process.!

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4.3 Increasing the Rate Growth of Hair Follicle!

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In relation to hair follicle, caffeine extracted from coffee grounds can help consumers maintain

their healthy follicle. It is uncommon for consumers to think that caffeine can help their hair to

reduce the amount of Ultraviolet-B rays from the sun, but it appears to be true by several studies

across the world. According to Fischer TW (2007), “Effect of Caffeine and Testosterone on The

Proliferation of Human Hair Follicles in Vitro,” the result of their test on caffeine shows how

caffeine leads to significant hair follicle growth. These results also have been confirmed

immunohistochemically by Ki-67 staining. In other words, the word immunohistochemically

means that a certain protein chain (Ki-67) in our body helps determining the antigens in a cell

tissue specifically hair tissue. This process clearly shows the effectiveness of caffeine for human

hair follicle despite all the critics by the readers about how caffeine has no effect on hair follicle.!

In addition to consumers with Androgenetic Alopecia (AGA), caffeine can help treat their scalp

hair in order to prevent them from getting further hair loss. Even though the process might be a

little tedious, the long term benefit from using caffeine shampoo is definitely worth the time.

However, there are some people who may argue that using coffee ground for the benefit of hair

is very time consuming and the reward is almost the same as using other healthy hair products

such as aloe vera, which has been proven to be a good source for maintaining healthy hair. There

are many more natural products that could help maintain our hair to be healthy. There are also

other effects aside from the benefits that could somehow destroy our hair. We have to diligently

see what may be good and bad source for our hair in every hair product we use, including coffee

grounds.!

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4.4 Protection From Skin Cancer!

The other type of benefit from coffee ground that people usually have no clue is skin cancer. It is

not common knowledge that coffee grounds can help us avoid skin cancer, but scientists already

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have shown some analysis regarding how caffeine can contribute its usefulness to skin cancer.

According to Dr. Alexa Patzelt MD. and her team, “The Role of Hair Follicles in the

Percutaneous Absorption of Caffeine” in 2007, claims that the applied caffeine helps reduce the

carcinogenesis or the initiation of establishing skin cancer. However, this claim is just a result of

lab testing. In other words, this test has not been done to real people to further see if the result is

the same as the lab testing or not. Coffee grounds also have the infamous two lipids that are

called kaweol and cafestol. These two lipids are known to scientists as anticancer.!

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Figure 2.2: Cafestol (left) and Kahweol (right)!

The figure for both cafestol and kahweol are very similar in terms of their chemical structure.

They both contain alcohol (-OH), the ring, and etc. However, if we look very closely, the only

difference that these two figure have is the double bond designated on number one and two. The

effects that these two lipids bring to coffee consumers are unquestionably potent. According to

Cavin, “Cafestol and Kahweol, two Coffee specific diterpenes with Anticarcinogenic Activity,”

cafestol and kahweol were shown to produce a wide range of biochemical effects resulting in a

reduction of the genotoxicity of several carcinogens that helps stabilize the activity inside the

body. However, just like for sun filter and facial mask, some people may not like the idea of

using reusable product such as coffee grounds to apply it to their skin. This brings out numerous

questions relating how many people are willing to get their hands dirty from using coffee

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grounds even though there are maybe alternative products that have the same result as coffee

grounds.!

4.5 Conclusion!

Not many people are comfortable enough to use caffeine from coffee grounds on their hair, face,

or skin because the texture of coffee grounds is nothing like a finished product from a certain

industry. The nice thing about coffee grounds is that it costs us nothing but a couple liter of

gasoline to drive to get the coffee grounds from the coffee shop. The price may also be reduced

to zero if we happen to use our own coffee ground from the coffee that we drink almost every

day. As people have different approach on what may work and not work for them. Caffeine from

coffee grounds is just another way to get a certain benefit related to beauty. It is completely our

call to determine what is good for our body, because risks and benefits are something that we

have to overcome whenever we deal with a new product.!

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5 Bio Oil!5.1 Introduction!

This portion of the environmental proposal discusses the process of hydrothermal liquefaction,

the corresponding procedures, and the characteristics of Bio-Oil.!

Bio Oil is one of the Upcycling products of spent coffee grounds. The production process goes

through a chemical engineering process called Hydrothermal Liquefaction. In a journal article,

“Hydrothermal Liquefaction of Spent Coffee Grounds in Water Medium for Bio-Oil

Production,” by Linxi Yang, Yang records his experiment with spent coffee grounds and

analyzes the characteristics of Bio-Oil. Hydrothermal liquefaction is an emerging technology that

converts wet biomass, or waste-organic materials, into biological oil and aqueous products at

high atmospheric pressure. Hydrothermal liquefaction is a hydrophobic process, which means

the process breaks down water compounds. Through this technology, spent coffee grounds are

being heated at high temperature and at high atmospheric pressure. Thus, the spent coffee

grounds liquefy; therefore, the spent coffee grounds turn into Bio-Oil.!

5.2 Experiment Procedure!

5.2.1 Material!

The wet spent coffee grounds are generally wet after being brewed. If the wetness of the spent

coffee grounds can be eliminated before going into the Hydrothermal Liquefaction, the ending

product, Bio-Oil, is easier and more likely to precipitate and to form the chemical structure. The

wet spent coffee grounds should be air-dry at room temperature for 3 days. After the air-dry

process, the spent coffee ground will be oven dried at 105 °C. The dried spent coffee grounds

should be kept in sealed bags and be stored in a refrigerator at 4 °C. In each Hydrothermal

Liquefaction process, the required amount of biomass must dried further in an oven at 105 °C for

24 hours. The proximate and ultimate chemical concentration analyses of dried spent coffee

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grounds should respectively contained around 82.3% volatiles, 1.4% ash, 4.0% moisture, 50.4%

Carbon concentration, 7.2% Hydrogen concentration, 2.1% Nitrogen concentration, and 40.3%

Oxygen concentration. These are the material preparation for the further production process.!

5.2.2 Hydrothermal Liquefaction Procedure!

According to Yang’s journal article, Yang’s experiments were carried out in a 100 cm3 stainless-

steel autoclave equipped with a stirrer. In a typical spinning process, 10 grams of dried spent

coffee grounds were weighed and loaded into the reactor; in addition, the mixture was followed

by the certain amount of distilled water with wanted hydro-feedstock mass ratios 5:1, 10:1, 15:1

and 20:1. The capacity of spinner in cubic centimeter was maintained between 50 cm3 to 60 cm3.

The spinner with the suspension of feedstock and distilled water was oscillated in an ultrasonic

bath for 3 minutes to confirm the mixture was well-mixed. Afterwards, the spinner was sealed; in

addition, the air inside the spinner was displaced by purging nitrogen several times. The spinner

was pressurized to 0.5 or 2.0 MPa with high purity nitrogen. The stirring speed was at 4.5 Hz,

the reacting mixture was ramped up to the pre-warmed temperature at different levels of high

temperatures, 200 °C, 225 °C, 250 °C, 275 °C and 300 °C, with a heating rate of 10 °C per

minute for achieving the ultimate drying process. After the system reached the desired

temperature, the reactor was kept at the temperature for a specified retention time for 30 minutes.

After the precipitation, the Bio-Oil was formed and was found inside the spinner.!

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5.3 Characterization of Bio-Oil!

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6.3 Table 1. Concentration of Elements in Bio-Oil!

According to Yang’s data collection, Table 1 shows the concentration of each element in the

Bio-Oil and the characteristics of Bio-oil. In the comparison of Carbon concentration, the

original spent coffee ground has 50.4% and the crude Bio-Oil has 71.2%. Clearly, Bio-Oil has a

higher Carbon concentration. This demonstrates the organic characteristic of Carbon-Carbon

molecular bond. The bond provides an efficient extraction with other organically existed

materials, such as dead skin and blackheads. The users of organically mixed Bio-Oil have a

better extraction of dead skin and blackheads when the users apply Bio-Oil as facial shampoo.

Other chemically mixed facial shampoos are basic-based; in other words, the basic effect

destroys the dead skin and blackheads in a more aggressive way. Unlike the organically formed

Bio-Oil taking an extraction approach, the chemically mixed facial shampoos are more harmful

to human skin.!

According to the Energy Recovery discovery from Yang’s experiment, the Energy Recovery has

72.6%. This demonstrates having each 100 grams of spent coffee grounds as input to the

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experiment; then, there will be expected to have 72.6 grams of Bio-Oil as the product. This

shows the efficiency in the production result since there is generally no cost of spent coffee

grounds.!

5.4 Conclusion!

Bio-Oil is an organically formed product. Bio-Oil is less aggressive and harmful comparing to

the other chemically formed facial shampoos. Although the costs for the infrastructure of this

experiment must be initiated by Starbucks Corporations, the overall return from the profit of

selling Bio-Oil product can be positively expected.!

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6 Tannins Extract!6.1 Introduction!

This portion of the environmental proposal introduces spent coffee grounds tannins as one of the

Upcycling product. According to an journal article, “The Influence of Extraction Parameters on

Spent Coffee Grounds as a Renewable Tannin Resource,” by Jiun Hor Low, he further

discussion discusses the general production method and the efficiency of productivity of the

method based on Low’s experiment and discovery.!

Tannins are hydro-soluble, naturally occurring, complex polyphenolic compounds that are

normally found in plants, such as oak trees, various types of woods, and coffee bean. Spent

coffee grounds can be considered as the steam purified forms of coffee beans. Originally, tannins

have been extensively utilized in leather industries. Tanning animal hides by converting the

protein of the raw hides into a stable material prevents the hides from decaying. In modern days,

plant tannins are receiving a favorable deal of commercial attention particularly in food and

beverage industries, pharmaceutical industries, and nutraceutical industries. Spent coffee ground

tannins have already had practices in coloring chocolates, in coloring wine, and in hair dying.!

6.2 Production Method!

The essence of this production method is a chemical reaction called acid-base extraction. In the

extraction process, the basic solution, sodium hydroxide, extracts the tannin acid compounds

from the spent coffee grounds.!

Figure 1 below is the chemical structure of the tannin acid in spent coffee grounds.!

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7.2 Figure 1. The structure of Tannin Acid!

In Low’s experiment, spent coffee grounds must be washed and be dried in oven at 120 °C. After

the spent coffee grounds were dried, the spent coffee grounds were mixed with sodium

hydroxide. The key factors in making this process successful were the concentration of sodium

hydroxide, extraction time, and the liquid-to-solid ratio on the yield of spent coffee grounds.!

6.3 Result of Acid-Base Extraction Experiment!

The results of Low’s experiment were examined in details by analyzing the concentration of

sodium hydroxide, extraction time, and the liquid-to-solid ratio. From the discoveries of

concentration of sodium hydroxide, the spent coffee grounds tannins was mostly formed with 5%

sodium hydroxide concentration in the extraction mixture when the extraction took place at the

temperature of 100°C. If the concentration of the sodium hydroxide drops to 2% at the same

temperature, the spent coffee grounds were less likely to precipitate and were reacting with a

slower rate. If the concentration of the sodium hydroxide rises to up to 9% at the reacting

temperature of 100°C, the sodium hydroxide would aggressively dissolve the spent coffee

grounds that were in the mixture. From the discoveries of extraction time, 90 minutes of

extraction time was the most optimal reaction period. From 60 minutes of extracting time to 90

minutes of extraction time, the spent coffee ground tannins formation increased from 21.02% to

29.69%. After 90 minutes period, there was no further reaction of the mixture of spent coffee

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grounds and sodium hydroxide. From the discoveries of liquid-and-solid ratio, the ratio was

found optimal at 8.23 coefficient.!

6.4 Conclusion!

Spent coffee ground tannins were successfully made through an acid-base extraction process. In

the extraction process, the variables such as the concentration of sodium hydroxide, extraction

time, extraction temperature, and the liquid-and-solid ratio had taken in consideration for

controlling the process to its most optimized state. Comparing with the costs of other types of

plant tannins, such as oak tannins and wood tannins, there is no initial cost for purchasing the

starting materials. Starbucks corporations can take this advantage with its spent coffee grounds,

then invests in tannin companies by either donating its spent coffee grounds or selling its spent

coffee grounds with low prices.!

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7 Energy and Electricity-Spent Coffee Ground Powered Fuel Cell!7.1 Introduction!

This portion of the environmental proposal discusses a case study of “Direct Power Generation

from Waste Coffee Grounds in a Biomass Fuel Cell” by NARA Cell Tech, Japan. The

experiment took place in substituting coal with spent coffee grounds as energy source for

generating electricity from a Solid Oxide Fuel Cell. Overall, the case study promotes a more

environmental friendly way of energy consumption by using spent coffee grounds.!

Biomass-powered power plants release less carbon dioxide emission comparing to coal-powered

power plants. In modern days, our plant is facing the problem of having excess greenhouse gases

in our atmosphere. Searching for alternative energy source is an action that must be initiated.

According to the research of NARA Cell Tech, spent coffee grounds can actually be used to

generate electricity. We believe Starbucks Corporations can donate their spent coffee grounds to

local engineering Universities as a way to distribute the waste treatment of spent coffee grounds.

The concepts of the experiment and the discoveries of the research are discussed in the sections

below.!

7.2 Concepts of the Experiment!

The basic concepts of this experiment are to operate an electricity generator. In this case, the

electricity generator was performed as a Solid Oxide Fuel Cell by NARA Cell Tech. In a fuel

cell system, there are two electrodes for creating current flow. The positively charged electrode

is called an anode; in addition, the negatively charged electrode is called a cathode. In terms of

the flow of the spent coffee grounds according to the experiment, spent coffee grounds initially

entered into the anode side of the fuel cell. Second, the spent coffee grounds were heated up to

900°C in order to perform oxidation. Oxidation is a chemical reaction that breaks down oxygen

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bonding in biomass for releasing electrons. Thus, the electrons can be conducted through anode

to a wire for electricity consumption. Figure.1 shows the flow of the experiment.!

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8.3 Figure 1. Demonstration of a Spent-Coffee-Ground powered Fuel Cell!

7.3 Data and Discoveries!

According to the results of the experiment performed by NARA Cell Tech, the spent-coffee-

ground-powered Solid Oxide Fuel Cell had a lower activation temperature, produced a higher

power density, and released 13.5% less of carbon dioxide emission comparing to the coal-

powered fuel cell.!

In terms of activation temperature, the spent-coffee-ground fuel cell could start performing

oxidation at the anode at 350°C. In comparison, the coal-powered fuel cell could only start the

oxidation at the anode at 550°C. This demonstrates there was too much waste heat in the coal-

powered fuel cell system even it was just to get the system to be ready. This discovery proves

that the spent-coffee-ground powered fuel cell has a lower requirement in operation.!

In terms of power density, the spent-coffee-ground fuel cell had a power density of 87.2

mW/cm-2; in comparison, the coal-powered fuel cell had a power density of 46.3 mW/cm-2.

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Clearly, the spent-coffee-ground fuel cell had a higher power density, which provided a higher

delivery of electricity. The two charts, (a) and (b), below show the Power Density diagrams of

the coal-powered fuel cell and the spent-coffee-ground powered fuel cell.!

!

8.3 Chart(a) coal and Chart(b) waste coffee grounds at different temperatures: ■ 750 °C, ● 800

°C, ▲ 850 °C, and ▼ 900 °C!

7.4 Conclusion!

The development of spent-coffee-ground powered power plant is still in the research step. This

type of research is usually performed in universities and technology institutions. We recommend

Starbucks Corporations to donate its spent coffee grounds to local educational institutions for

further researches. The action of supporting education can directly build up the reputation of

Starbucks Corporations.!

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8 Grounds Used as a Raw Product !8.1 Introduction!

Coffee grounds do not have to be heavily reprocessed to create upcycled products, such as

cosmetics or biomass fuel. If one wishes, the coffee grounds can be utilized as is directly after

being spent for coffee. This is true due to the physical and chemical nature of coffee grounds.

The grounds can be used to generate many products, but the most effective products created from

raw coffee grounds can be centralized into either household or gardening products.!

8.2 Natural Properties of Coffee Grounds!

To fully understand why spent coffee grounds are such a potent product as is, its basic properties

must be understood. The

natural acidity of spent coffee

grounds resides in the 6.5 pH

range (Oregon State

University). Additionally,

coffee grounds are gritty in

nature due to high fiber

content (Ballestros).!

Not only are the fibers tough, but they are large in nature, with most granule diameters in the 500

micron range, as shown by Figure Blah. Unsurprisingly, coffee grounds also decompose quickly

but only in a very aerated environment. As coffee grounds decompose, it releases abundant

amounts of nitrogen and several forms of fungus. !

!

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8.3 Household Applications!

Due to the acidic nature of spent coffee grounds, it works great across the household for

various uses as is. Some of these uses include unclogging drains and assisting in dishwashing.

Additionally given the strong odor of coffee grounds, it is obvious the substance would work

effectively as an odor neutralizer. While coffee grounds can neutralize the odors that persist in

the food processor often found in the kitchen sink, coffee grounds also have the ability of

unclogging drains, much like the industrial solution commonly known as Dran-O. As most

dishwasher detergents are basic by chemical composition, it is obvious coffee grounds would

chemically react with this soap. There are a few byproducts created by this reaction; However,

the one byproduct that makes this reaction useful to unclog the drain is heat. The reason most

drains clog is from a backlog of grease, a nonpolar substance. Dishwasher soap may be able to

remove stuck grease to a certain degree, but soap alone is not enough to unclog a properly stuck

drain. This is where the heat comes into play: heat converts solid grease into liquid oils, thus

letting liquids flow past it. Unlike chemical based drain cleaners, coffee grounds will not create

long term damages in the wastewater system due to its ease of decomposition. Not only do some

chemicals used in industrial drain cleaner attack the metalworking in the sewage system, but the

chemicals are often harmful to the environment. In 2002, 60-70% of sampled streams contained

persistent detergent metabolites and disinfectants as shown in figure, which are known chemicals

in drain cleaner (Buxton). These chemicals are known to wreak havoc on marine ecosystems. By

utilizing coffee grounds as a drain cleaner substitute, marine based ecosystems may be affected

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far less in addition to not damaging the sewage system that gets our waste out to a treatment

plant.!

It may seem weird to utilize coffee grounds exclusively for unclogging household

plumbing; This does not have to be the case. Recall that most coffee granules have an overall

diameter of 500 microns which is extremely close to the preferred diameter of pumicite utilized

in abrasive applications, such as cleaning or polishing (Pumex S.P.A.). Due to the nearly zero

size difference between pumice granules optimized for cleaning and coffee grounds, it is clear

the two materials can be substituted for certain applications. In the household, this may come in

the form of abrasive cleaning on stubborn food

items on dishes. !

8.4 Gardening Applications!

Perhaps the thought of utilizing spent coffee

beans in the household exclusively does not sit well

with some. Well, not to worry. Coffee grounds can

be effectively utilized in gardening applications.

Some of these applications include compost, insect

repellant, and even fertilizer. !

Recall the basic properties of spent coffee

grounds: acidic and extremely biodegradable. When

coffee grounds are placed in a compost pile, they

will break down quickly into lower level materials,

such as nitrogen. The most potent component of

commercial plant food is nitrogen. As the coffee

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grounds break down, they raise the nitrogen levels of the soil which makes the compost soil very

potent to rapidly grow plants. Additionally, the acidic content will actually help certain plants

thrive.!

Another side effect of the usage of coffee grounds in the garden is that the coffee will

naturally drive away insects, such as slugs or snails. The true yield of coffee grounds to make

coffee is not 100%. There are some components in the grounds that are not extracted, such as

caffeine, a toxin by nature. The plants will absorb the remaining caffeine in the grounds, which is

distributed among the entire plant. Certain insects such as slugs are extremely sensitive to

caffeine. Slugs will ultimately stay away from these caffeine strained plants, thus rendering

coffee grounds a natural insecticide. By utilizing more environmentally friendly pesticides, also

known as biopesticides, we can approach a more sustainable future with less risks of creating an

environment that even humans would not be able to cope with (Gonzalez-Coloma).!

Of course, if one is too time-stricken to convert coffee grounds into compost, the grounds

can actually be used directly as fertilizer. Although the positive health effects upon plants do not

occur on the same magnitude, spent coffee grounds will be removed from the landfill system. !

8.5 Conclusion!

If Starbucks does not wish to significantly drive up the operation costs of the franchise from

repurposing its spent coffee grounds on cosmetic and biomass products, there are other lower

cost options available, such as expanding its Grounds for Your Garden program to further reduce

Starbucks’ impact on landfills. This expansion should be done in both the garden and the

household. By performing this expansion, Starbucks would give the general public a very clear

statement: Starbucks is actively trying to reduce its negative impact on the environment with its

products and needs the public’s help to make this a reality. This reduction of products entering

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the landfill waste management system is the first step in bringing humanity towards a more

sustainable future. !

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9 Overall cost analysis !

Empirical marketing data from 2014 has shown Starbucks has huge operation costs. In

that year alone, the Starbucks corporation had a whopping 6.8 million USD in operation costs

(Jones). By omitting the raw cost of purchasing coffee beans, we can see the corporation spent

3.944 billion US dollars for the other various operational costs. This breaks down into roughly a

$19 per ton premium over the base cost of coffee beans. The addition of other products will add

an additional cost to running Starbucks. However, the magnitude of the gross cost is ultimately

decided by the administrative board of Starbucks Corporation.!

By comparing the true cost of pre-existing products to the anticipated future products of

the Starbucks Corporation, we

can see that these products

have a very small impact on

the operation cost of the

corporation. As displayed by

figure blah(graph) , the

summation of the cost of all

potential products

recommended by this paper is a mere $0.22 premium per ton of coffee grounds on the total

running cost of Starbucks, a mere drop in the bucket for the operational cost of Starbucks.

However, there is one major issue. Recall the product life cycle consists of development,

manufacturing, and distribution. All these new products, regardless how much processing for

upcycling, need to get back to market. !

! 32!

It is the unfortunate nature of humans to avoid products that do not satisfy our initial

impressions. We avoid any product that is not sufficiently marketed or distributed. In a quick

poll conducted in ENGR392 at SJSU on 03 May 2016, a whopping 95% of people were

completely unaware of the Grounds for Your Garden program even though it has been running

for over 20 years. Starbucks must market these products sufficiently to minimize any losses

within the corporation. Based on the 2014 data, it is suggested Starbucks Corporation spends an

additional $0.80, $0.40, and $0.30 per ton of coffee grounds on packaging, marketing, and

distribution of these products. Not all of the grounds have to be upcycled for Starbucks

Corporation purposes. As mentioned in previous sections, it is highly recommended the

Starbucks Corporation places their grounds in the hands of people who are already making these

highly processed products possible, such as Bio-Oil or Bio-Bean.!

!

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10 Final Conclusion and Recommendation!Upcycling !

There are three main subgroups of recycling: downcycling, recycling, and upcycling.

Downcycling is an economically worthless process while recycling and upcycling make the

product more usable for future purposes. Due to the nature that used coffee grounds cannot be

effectively recycled, it is recommended that Starbucks Corp. upcycle it’s used coffee grounds

instead of downcycle them into the landfills.!

Cosmetics!

Not many people are comfortable enough to use caffeine from coffee grounds on their

hair, face, or skin because the texture of coffee grounds is nothing like a finished product from a

certain industry. The nice thing about coffee grounds is that it costs us nothing but a couple liter

of gasoline to drive to get the coffee grounds from the coffee shop. The price may also be

reduced to zero if we happen to use our own coffee ground from the coffee that we drink almost

every day. As people have different approach on what may work and not work for them.

Caffeine from coffee grounds is just another way to get a certain benefit related to beauty. It is

completely our call to determine what is good for our body, because risks and benefits are

something that we have to overcome whenever we deal with a new product.!

Bio-oil!

Bio-Oil is an organically formed product. Bio-Oil is less aggressive and harmful comparing to

the other chemically formed facial shampoos. Although the costs for the infrastructure of this

experiment must be initiated by Starbucks Corporations, the overall return from the profit of

selling Bio-Oil product can be positively expected.!

Tannis Extract!

! 34!

Spent coffee ground tannins were successfully made through an acid-base extraction process. In

the extraction process, the variables such as the concentration of sodium hydroxide, extraction

time, extraction temperature, and the liquid-and-solid ratio had taken in consideration for

controlling the process to its most optimized state. Comparing with the costs of other types of

plant tannins, such as oak tannins and wood tannins, there is no initial cost for purchasing the

starting materials. Starbucks corporations can take this advantage with its spent coffee grounds,

then invests in tannin companies by either donating its spent coffee grounds or selling its spent

coffee grounds with low prices.!

Coffee Ground Fuel Cell!

The development of spent-coffee-ground powered power plant is still in the research step. This

type of research is usually performed in universities and technology institutions. We recommend

Starbucks Corporations to donate its spent coffee grounds to local educational institutions for

further researches. The action of supporting education can directly build up the reputation of

Starbucks Corporations.!

Raw Products!

If Starbucks does not wish to significantly drive up the operation costs of the franchise from

repurposing its spent coffee grounds on cosmetic and biomass products, there are other lower

cost options available, such as expanding its Grounds for Your Garden program to further reduce

Starbucks’ impact on landfills. This expansion should be done in both the garden and the

household. By performing this expansion, Starbucks would give the general public a very clear

statement: Starbucks is actively trying to reduce its negative impact on the environment with its

products and needs the public’s help to make this a reality. This reduction of products entering

! 35!

the landfill waste management system is the first step in bringing humanity towards a more

sustainable future!

Cost Analysis, feasibility for Starbucks Corp.!

It is cheap. Do it.!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

! 36!

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