Design Life-Cycle

 Ruoxi, Peng

Group Member: Christina Lin

DES 40A

Professor Cogdell

Life Cycle of Numi Tea Bag - Raw Materials

I.                Introduction

Tea is a common and ancient beverage originates in China, and spreads around the world in a long history. In order to keep tea leaves for long time and simplify the steps for boiling a cup of tea, people created tea bags. While people enjoying this new convenient way of drinking tea, whether tea bags are environmental-friendly and harmless to the human body has become a widely concerned issue.

As a company focused on providing organic tea for consumers, Numi takes responsibility to minimize and offset their carbon emissions by using recyclable cardboard packaging for their products. This company also intends to choose biodegradable materials that minimize the negative impact on the environment.

In this paper, I will report on the raw materials used for the making of Numi tea bag, which includes biodegradable filter-paper, soy-based inks, and paper tags, by focusing on each of their acquisition, processing, transportation, maintenance, recycling, and waste management.

II.         Biodegradable Filter Paper

Filter paper used in Numi tea bag is made by the hemp-based paper. The raw material used to make a hemp paper is fiber from Manila hemp, also named Abacá. Manila hemp is widely grown as a commercial corp in the Philippines, Ecuador, and Costa Rica, and the US companies import this natural fiber largely from the Philippines and Ecuador.

To make hemp paper from Manila hemp fiber, the process can be simply concluded as following steps: Cleaning, fiberizing, cutting, classification, bleaching, and refining (Roekel). At the beginning of the paper making process, all non-fibrous components need to be removed from the raw material. Then, the remaining fibers need to be mechanically tearing apart to make the “pulp”. This process is called fiberizing. Sometimes fiberizing need the participation of chemicals, but for Manila hemp fiber, mechanical way is preferred. Let’s leave out the physical process, cutting and classification, and specifically talks about bleaching. Bleaching is a process that uses chemicals to let paper have higher whiteness. For most of the modern pulp mills, oxygen-based bleaching is widely used, which needs compounds like oxygen, ozone, and peroxide during the bleaching process. Further, the Manila hemp pulp can be bleached with more harmless hydrogen peroxide. After refining, the Manila fiber successfully becomes completed pulp. In order to make pulp into papers, the further process includes dilution, formation, drying, and sheeting. Dilution process requires very large amounts of water to dilute the original pulp, nearly 200 times as much water as fiber pulp. The water would be wiped off in the formation process, and reuse for the next papermaking process, but there is still some water would be evaporated during the drying process. (Hayase)

“Today 85% of Manila hemp is produced in the Philippines, and 80% is used as material for paper and 15% for rope within the country. Hard fiber, represented by Abacá (Manila hemp), has been produced almost exclusively in the Philippines. (Hayase)” Obviously, for Numi tea bags, the filter papers are imported from the Philippines. The transportation process required fossil fuels as the prime mover of ships and carts.

Since the tea bags are only used once or twice, the hemp-based filter papers are not expected to be reused. Obviously, consumers would put the used tea bags into food waste garbage bins: we should not expect that they would separate the filter paper part, and the tea leaves inside before throwing them away. Instead, the filter papers used in Numi tea bags are biodegradable and can be directly composed in home backyard as fertilizer. Since hemp-based filter paper does not contain plastic compounds, it is 100% home compostable. 

After analyzing the filter paper used to make the main part of tea bags, let’s put our attention on another paper product: Paper tag.

III.       Paper tag

Although the material used to produce paper tags is also paper, it has a huge difference between filter paper. Paper tag is made by cardstock with matte coating, and printed with soy-based ink, which I will discuss in the following paragraphs. Also, Numi’s paper tags contain cotton wires to fix it on the tea bags. Compared with the hemp-based paper, cardstocks are much thicker and heavier, which make them durable to be colored and printed. The material for cardstock in Numi tea bags’ paper tags is linen paper.

First, let’s talk about the main part of the paper tag, the linen paper. Compared with Manila hemp, linen is more commonly used in papermaking, and has wider usages. The raw material of linen paper is fiber from flax plants, which is produced in lots of countries. China is the largest flax exporter in the world, and the US is one of its big customers. The papermaking process of linen paper is basically the same as I mentioned in the production process of the hemp-based filter paper. However, there is still something different. For example, during the bleaching process, there are more chemicals included, such as oxygen and ozone, but still avoid using chlorine compounds that have harmful effect to the environment.

Since the detailed making process is already specifically interpreted in the previous paragraphs, I would jump to the other raw material used to make paper tags: Cotton.

As a soft and fluffy fiber that is widely produced in the world, cotton is most often spun into threads. In the past, this is a manual process that requires human forces, but today this work is taken by the cotton spinning machines. These machines require electricity, which originally needs to consume fossil fuels like carbon and gasoline.

As I said before, there is one important material used to print information on the paper tag, the soy-based ink.

IV.       Soy-based ink

Soy-based ink, literally, is a kind of ink made from soybeans. As opposed to traditional petroleum-based ink, soy ink is more environmentally friendly, and easier to make recycled paper (Sun).

The producing process of soy-based ink can be divided into two parts. The aim of the first part is getting soy oil from harvested soybeans. In the first step, the soybeans need to be cleaned, dulled, and dried as preparation. The cleaned soybeans would be poured into mechanical rollers that make small flakes used for further processing. Then is the extraction process which uses hexane or other solvents to wash the soybean oil from soybean flakes. After soy oil has been successfully extracted, the solvent becomes useless and needs to be removed, which requires a distillation process that separates out the oil. Then is the second part, the extracted soy oil would be mixed with pigments, resins, and waxes. Pigments are used for making different colors of soy ink. Actually, there are nearly hundreds of types of pigments used in soy ink in order to produce various colors. For example, the main raw material for black pigments in the market is carbon black, while other colorful pigments require different kinds of chemicals like zinc oxide for white, and lithol for red color. Resin works as binders that combine other ingredients of ink together, then make the soy ink print firmly on the paper. Waxes are used to increase inks’ resistance to water and solvents.

The United States is the country that produces most of the soybeans in the world, accounts for 34 percent for the world soybean production. Soybeans require approximately 15 inches to over 25 inches of water per year, and they can be harvested by reaper machines 45 to 65 days after sowing. The abundant soybean resources in local land lead to less transportation consumption, because it is not necessary to import raw materials from other countries anymore.

Although soybean products are biodegradable, soy ink is not edible or 100% biodegradable because of the additives such as pigments that mixed with oil are the same as those used in petroleum-based inks. But, compared with the standard ink, soy ink is still much more biodegradable because of the little content of the chemical additives. Soy-based ink still has many benefits. For example, soy ink can be easily removed from the printing paper during the de-inking process, which means that this kind of ink is highly recyclable and reusable.

Bibliography

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Herzog, Michael. Pre-Gummed Tea Bag Tag Assembly. 8 May 1979.

“How Soy-Based Ink Is Made, and Why You Should Use It.” Printwand, 23 Mar. 2018, www.printwand.com/blog/how-soy-based-ink-is-made-and-why-you-should-use-it.

Morton, Julia F. “Rooibos Tea,Aspalathus Linearis, a Caffeineless, Low-Tannin Beverage.” Economic Botany, vol. 37, no. 2, 1983, pp. 164–173., doi:10.1007/bf02858780.

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Roekel, Gertjan van. “Hemp Pulp and Paper Production.” Hemp Pulp and Paper Production, 2019, www.druglibrary.net/olsen/HEMP/IHA/iha01105.html.

“Soy Ink.” Wikipedia, Wikimedia Foundation, 28 Sept. 2019, en.wikipedia.org/wiki/Soy_ink.

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Sun, Susan. “Bio-Based Polymers and Composites.” 2005, doi:10.1016/b978-0-12-763952-9.x5000-x.

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“Why Organic Tea?” Numi Organic Tea, numitea.com/why-organic-tea/.

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Lin, Christina 

Rosie Peng 

DES 40A 

Professor Cogdell 

 Embodied Energy in the Production of Numi Tea Bags 

The origin of the tea bag arose from efforts to diminish waste. Roberta C. Lawson and Mary Mclaren, two women who were the first to patent a Tea-Leaf Holder in 1901, designed a folded cotton bag to contain tea leaves so that people could produce a cup of fresh tea that could be consumed immediately instead of preparing a large portion of tea at a time and having to throw it away after it became stale (Lawson and McLaren). Although they were unsuccessful in marketing their tea-leaf holder, coincidence brought the tea bag to popularity when Thomas Sullivan, a tea importer, began packaging his tea in silk bags. Instead of opening up these bags, his customers started using them as tea infusers, and eventually, tea bags became a common household product due to its convenience (Goodwin). Concern for convenience rather than for waste or the environment now steeps the teabag industry; tea bags commonly contain plastic which requires the burning of fossil fuels during its production process. However, there are still a few tea companies that value sustainability, one of which is Numi. By examining the embodied energy of a Numi tea bag, we can see how Numi takes on responsibility to uphold environmentally friendly acquisition of raw materials, production, distribution, and outcomes for their product; yet the energy expended to produce tea bags still prompts us to question if we really need them.    

The life cycle of a Numi tea bag begins with acquiring raw materials: manila hemp cellulose for the bag, cotton for the string, zinc and iron for the staple attaching the tag to the bag, as well as raw materials to create soy ink.  Manila hemp fiber acquisition is largely dependent on manpower. Every hectare of manila hemp requires 15 man-days of field preparation, 10 man-days of preparing suckers, 20 man-days of planting, and 80 man-days pf weeding and underbrushing. 18 months of after planting, the manila hemp is ready to be harvested and have its fiber extracted. The area around the hemp stalks are cleared. Then, they go through a process of topping, removal of hemp leaves, tumbling, cutting of the stalks, and tuxying, separation of the outer section from the inner section of the stalk. Finally, the fiber can be stripped from the stalks. This takes 23 man-days/Ha, and the final step before the manila hemp cellulose is transported to a grading and baling facility is drying which takes 3 man-days/Ha. The manila hemp fiber is then put through a process of inspection, sorting, grading, classifying, and weighing before it is graded and baled with a 50 HP baling machine that consumes approximately 42.6 kw/hr of electricity (Cortez, et al.). Unlike manila hemp, cotton requires more energy expenditure and machinery to produce. One metric ton of conventional seed cotton needs approximately 21,600 MJ for irrigation, 50L/Ha of diesel to power tractors, and 2880 MJ of crude oil and natural gas to produce fertilizers. Other processes that require machinery are ginning, the separation of lint and seed, cleaning, and baling after the cotton has been harvested (“LCA of Cotton Cultivation Systems”). Staples are only a small part of a tea bag, but the energy needed to extract zinc and iron from their ores in order to make staples may be one of the largest contributors of energy expenditure in this step of the Numi tea bag life cycle. Zinc mining and production requires 5860-27,300 MJ of nonrenewable energy (crude oil, hard coal, lignite, natural gas, peat, and uranium)  and 771-10,143 MJ of renewable energy (geothermics, hydropower, solar energy, and wind power) per metric ton of Zn, and iron production requires around 153 MJ of diesel, explosives, and electricity/t iron ore (Genderen, Haque, and Norgate). Finally, soy ink begins with soybean production which relies on fuel, electricity, fertilizers, and machinery including tractors, harvesters, seeders, and spraying machines, totaling 4,032 – 15,506 MJ/ha (Energy in Soybean Agriculture). In addition to soybeans, soy ink production commonly includes formaldehyde, glycerol, a product of cattle slaughtering, petroleum products, flax seed, linseed, and tung nut, all of which also need energy to be produced and acquired (Simpson, et al.). At this point, we have consumed a lot of energy but only acquired the raw materials needed to be manufactured, processed, and formulated into a tea bag.  

Once the raw materials have been acquired, energy must be used to process cotton into string, soybeans into soy ink, recycled materials into paper, iron and zinc into staples, and hemp into bags. Using a spinning machine, cotton can be spun into yarn. Though the string attached to a tea bag is not entirely the same as yarn, for reference, 1 kg of yarn requires around 3.23-3.76 kWh of electricity (Slipperly, et al.). Processing soybeans into soy ink begins with extracting soybean oil from soybean flakes using hexane, which is produced by refining crude oil, as a solvent. Once the soybean oil is extracted, the soybean oil is filtered and purified before it is cooked and blended with pigments, resins, and waxes (proportions depend on the manufacturer). A life cycle analysis of soy-based ink printing found that tall oil rosin manufacturing (1.92E+09 J/FU) and electricity generation (1.31 E+09 J/FU) contribute the most energy consumption to the embodied energy of soy ink printing, while printing (4.83E+08 J/FU), ink production (1.70E+07 J/FU), crude oil extraction (5.66E+06J/FU), resin manufacture from linseed oil (2.25E+06 J/FU), flax seed processing (2.27E+06 J/FU), formaldehyde production (1.55E+06 J/FU), and nut milling (4.36E+05J/FU) only consume a small percentage of the total energy. As seen, the production of soy ink consumes a lot of energy and contains a considerable percentage of petroleum-based products, but it still contains less petroleum compared to traditional petroleum-based ink, providing a better alternative (Simpson, et al.). Another environmentally conscious decision Numi has made is to use recycled paper for their tags rather than processing virgin paper.  According to a life-cycle assessment for paper products performed by the Environmental Defense Fund, the production of recycled-fiber-based paper and virgin-fiber-based paper both rely on power from coal, oil, natural gas, nuclear power, and hydropower, but recycled-fiber-based papers require less total energy than virgin-fiber-based paper (Denison). The production of staples requires the production of steel from iron which consumes coal, natural gas, and electricity to power the machinery involved. Steel is then plated with zinc through a chemical process called galvanization which consumes 3.4 - 5.3 MJ per kg of steel (Galvanized Steel). Galvanized steel is made into a thick coil of wire that is transported to factories where the strips of wire are cut into small segments and put through a press that creates the bent legs of the staple. Though the exact amounts of energy needed to produce staples are unclear, staple production likely depends on a combination of chemical and electrical energy. Finally, the bent pieces are bundled and packaged. From our research, it is unclear how manila hemp is processed into tea bags, but it is likely spun first before either being woven or mechanically, chemically, or thermally formed into a tea bag. Furthermore, Numi claims that their product is unbleached, but they use an oxygen process to whiten their tea bags (Numi). Since it is unclear what this process is, we were unable to calculate the energy consumed during this portion of the tea bag production process. Once energy is expended to process raw materials into different parts of the tea bag, each of these parts must be shipped to facilities where the tea bag can be assembled.   

Made from raw materials originating from different areas of the world, Numi tea bags cannot be assembled and made accessible to customers without transportation. The majority of the world’s manila hemp is produced in the Philippines, meaning that it must be shipped miles to reach Numi facilities. Before it leaves the Philippines, manila hemp is transported to grading and baling facilities and traded locally which requires about 11.2L of diesel/ton of manila hemp (Cortez et al.). Cotton and soybeans also must be transported from farm to factory before it can be spun into string or processed into soy ink, but it was not possible for us to calculate the distance that they would have to travel since we do not know where Numi gets their cotton and soy ink or where Numi produces its tea bags. We were also unable to determine whether these materials are transported by trucks, ships, planes, or other forms of vehicles, making it impossible to determine what kind of fuel was used. According to the life-cycle assessment for paper products performed by the Environmental Defense Fund, recycled paper consumes 205.2 Btus/ton of paper in transportation during its life cycle from production to the market. In comparison to virgin-fiber-based paper, recycled paper can appear to use more energy in transportation, but the energy needed to transport harvested trees and pulp for virgin-fiber-based paper also requires a considerable amount of energy (Denison). Along with all other raw materials, extracted iron and zinc need to be transported to factories where staples are made and then delivered to Numi facilities. Numi products are sold internationally in more than 20 countries, and the distribution of these products are the result of miles of transportation fueled by diesel, electricity, or jet fuel (Numi). The energy going into transportation includes transportation of raw materials to factories and the end product to its customers, but the life-cycle of a tea bag doesn’t end at transportation.  

Once the tea bag is in the hands of its consumer, energy must be put into making tea and disposing it after the cup of tea has been consumed. Like all other tea bags, Numi tea bags are designed to only be used once or twice before being thrown away, but fortunately, the Numi tea bag life cycle doesn’t end at the landfill since Numi has chosen to produce its tea bags from compostable materials. Some tea bags will inevitably end up in the landfill since the fate of the tea bag is in the hands of its consumer, and according to a survey conducted for the National Waste & Recycling Association, 72% of Americans do not compost their organic material due to inconvenience (Gerlat). Nevertheless, Numi tea bags are meant to be composted which only requires the mechanical energy of one person to toss the tea bag in a compost pile or compost bin. With municipal composting, energy in the form of diesel must be consumed to transport the compost material to a local compost facility, but in general, composting produces energy rather than consumes energy through the help of microorganisms that break down organic material into nutrient dense soil and release heat during this process, and it is a better alternative to landfill disposal which emits methane gas (Ross). With the raw materials Numi has decided to use, Numi has provided an environmentally friendly outcome for their product.  

Our analysis of the embodied energy of a Numi tea bag demonstrate how Numi has been making environmentally conscious decisions in terms of the acquisition, production, distribution, and disposal of its tea bags. While we were unable to completely uncover the embodied energy or calculate the exact amount of energy that goes into produce a Numi tea bag, our life cycle assessment allowed us to catch of glimpse of how much energy is required to transport raw materials, process them, deliver the end product, and dispose of it. Numi has made environmentally conscious decisions such as producing their tea bags from manila hemp rather than plastics or nylon, using soy ink rather than petroleum-based inks, recycled paper instead of virgin-fiber-based papers, and using compostable materials; however, the amount of electricity, diesel, crude oil, natural gas, and other resources needed to produce a tea bag prompt us to question its necessity. Currently, Numi also sells loose leaf tea as one of its products which requires less packaging then individual wrapped tea bags. If we value sustainability, lose leaf tea could be the way to go. Even tea connoisseurs seem to prefer the taste of tea brewed from lose leaves rather than from tea bags.  

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