Design Life-Cycle

Kaila Ho

Eldy Lazaro

Spring 2024

ATLS 4519 Sustainable Design

Life Cycle Assessment of EnviroIce Gel Ice Packs

Ice packs are widely used to transport and ship goods to consumers that need to be kept cold in a variety of industries. The EnviroIce Gel Ice Pack is Pelton Shepherd's and Frosty Tech’s environmentally friendly solution for single-use gel ice packs that can be used for cold transportation and shipping needs. The ice packs are considered “eco friendly” because the solvents in the gel can be diluted with water and used as fertilizer for houseplants or be safely poured down the drain, unlike other more toxic ice pack gels. The product consists of a painted outer plastic outer packaging filled with a gel that helps the product remain cool for long periods of time. Additionally, the low density polyethylene plastic can be recycled in most areas. This product largely appeals to companies that wish to be more environmentally conscious, and consumers who are interested in the plant-fertilizing nature of the ice pack gel. As a plant-enthusiast, I found this aspect of the ice pack to be the most interesting and through further research began to understand the scope and importance of the product. This qualitative life cycle assessment (LCA) will explore the life cycle of the EnviroIce gel pack from the raw materials phase to the waste management phase. First we will discuss each of the raw materials needed in the raw materials acquisition, processing and manufacturing, transportation and distribution, use and reuse, and waste management phases. We will then explore the embodied energy necessary in each of the same phases. Finally, the waste and pollution that results as part of the product’s life cycle in each phase will be discussed as well. After thorough assessment of the EnviroIce gel pack’s life cycle, it becomes clear that while the EnviroIce gel packs are designed and marketed to be environmentally friendly, there are numerous factors that may detract from the sustainability of the product in each phase from raw material acquisition to waste management. 

Raw Materials 

In each phase of its life cycle, an EnviroIce gel pack requires several raw materials that must be taken into account when considering the overall sustainability of the product. Each ice pack contains a gel consisting of urea, potassium nitrate, sodium nitrate, ammonium nitrate, and ammonium phosphate, and a container consisting of low density polyethylene (LDPE) and acrylic paint. Additional raw materials necessary for the energy needed throughout the product’s life cycle must be considered as well. 

Raw Materials Acquisition

The raw materials required in the material sourcing process for EnviroIce gel pack include several different virgin materials required to source each component of the product. While this information was not available, it is important to keep in mind that the acquisition and creation of these compounds may happen on the manufacturing site for the ice pack itself, or  could happen at a different location and then be transported. If the latter is the case, then it is important to keep in mind that the raw material of fuel is required to transport the materials from one site to another. 

One of the key compounds, ammonium nitrate involves the creation of ammonia, which is then combined with rock phosphate and nitric acid. To manufacture ammonia “Hydrogen is obtained from a variety of sources such as water, cokeoven gas, naptha, fuel oil, coal, natural gas etc.” (Cherimisinoff). Rock phosphate involves limestone and nitric acid must be manufactured on its own, which could both be life cycle assessments of their own, but must still be considered in the scope of this product. 

Urea, another key factor in the gel for the ice packs, “is manufactured by the reaction of ammonia and carbon dioxide to form ammonium carbamate first. Ammonium carbamate is then dehydrated” (Cherimisinoff). This means that the key ingredients of urea are ammonia, whose production is discussed above, and carbon dioxide, which is abundantly available in the atmosphere. 

Ammonium phosphate, another key compound, is produced “by neutralization of sulphuric acid and phosphoric acid by ammonia and granulating the resulting slurry” (Cherimisinoff). While sulfuric acid and phosphoric acid could have life cycle assessments of their own, it is important to consider them in the scope of this product. Sulfuric acid consists of sulfur and oxygen, while phosphoric acid consists of hydrogen, phosphorus, and oxygen. 

Sodium nitrate, a nitrate salt often used in fertilizer “is produced commercially via the reaction of nitrogen oxides with sodium carbonate or sodium hydroxide solutions” (Agency for Toxic Substances and Disease Registry). This is a complex compound consisting of the elements sodium, carbon, oxygen, and hydrogen based on the chemical formula. These elements are all relatively readily available in the atmosphere or the earth’s crust. 

Potassium nitrate is made “from potassium chloride and a source of nitrate, such as sodium nitrate, ammonium nitrate, or nitric acid” (Allen). Conveniently, this raw material can be formed through synthesis with other raw materials for this ice pack (sodium nitrate and ammonium nitrate), which reduces the amount of new materials needed to create this compound. 

LDPE, used as the outer casing and container for the gel, can be described as: “Monomers of ethylene are polymerized at HDPE conditions along with co-monomers of 1-butene, 1-hexene, or 1-octene, producing a linear copolymer” (Selke). Ethylene and the other involved monomers are organic compounds consisting of hydrogen and carbon, which are both naturally occurring and then manufactured into the appropriate materials. Similarly, it is likely that the LDPE and the paint and adhesives for it are manufactured elsewhere and then transported to the manufacturing site of the gel ice packs; again, if this is the case, fuel for its transportation must be factored into the raw materials as well. 

Processing & Manufacturing

The processing and manufacturing phase of the EnviroIce pack’s life cycle involves several raw materials in the form of energy and the raw materials involved in the manufacturing plants. According to the Pelton Shepherd industry page for the product, the ice packs are produced within the United States, where most manufacturing energy is natural gas and fossil fuels (EIA), which are both considered raw materials for manufacturing. While it will not be discussed in depth in this life cycle assessment, the materials needed to build the manufacturing devices in each production plant must be considered as well. 

Distribution

In the distribution phase, there are cold centers and semi-truck transportation involved. As will be discussed in the embodied energy section, the cold centers required to keep this product cool until it is ready for use use a large amount of energy in the form of natural gas and fossil fuels (EIA). Additionally, there is a large energy requirement in the form of gasoline to transport the product within the United States, likely via semi-trucks. 

Additionally, the ice packs are likely shipped on pallets or in cardboard boxes, adding yet another factor to consider in the raw materials phase of the product’s life cycle. Again, these items are likely manufactured elsewhere and must be transported to Pelton Shepherd industries for their use. 

Use and Reuse 

The use and reuse phase of this product is the least energy intensive part of the process with the raw material being human energy needed to move the product to shipping containers where it may be needed, as well as the energy required to dilute the gel contents with water and then fertilize plants with it and either throw away or recycle the plastic container. The water that the gel gets mixed with to be used as fertilizer for plants can also be considered a raw material.  The energy required for this process depends largely on how the consumer chooses to use the product.

Another factor in the use and reuse cycle is the fact that even though the product is considered single-use (i.e. the ice pack would arrive with food, drugs, or  other chilled items that a consumer ordered), they may choose to freeze it and use it again. If they choose to put it in the freezer, energy likely derived from natural gas and fossil fuels (EIA) is required to keep the freezer cool.

Waste

In the waste phase of this product, the main raw materials required are the gasoline to transport the waste to either a landfill or recycling facility depending on how the user decides to dispose of the product. There is also energy that is used at these facilities to process the waste, whether that is sorting for a landfill or recycling the LDPE into new plastic. While there is limited information about what type of energy is used at these facilities and it largely depends on the location of the facility, it can be assumed that a large majority of these facilities use fossil fuels or natural gas (EIA). 

Embodied Energy

Each phase of the EnviroIce gel pack’s life cycle  including raw materials acquisition, processing and manufacturing, transportation and distribution, use and reuse, and waste management involves energy use. The ice pack is made up of two key parts: the plastic container and the gel. The materials for the container include low density polyethylene (LDPE) and acrylic paint. According to a patent issued to Frosty Tech industries, the manufacturer of the product, the gel consists of urea, potassium nitrate, sodium nitrate, ammonium nitrate, ammonium phosphate, and water. The focus for this section of the LCA will be the 12oz (340g) product size with the assumption that 5g of the total weight is the plastic container and the remaining 335g is the gel. Based on available information from the Pelton Shepherd shipping page and for the purposes of this assessment, it can be assumed that this product is manufactured and distributed solely within the United States. 

Raw Material Acquisition and Production

For each component of the EnviroIce gel pack, the raw materials must be acquired and then processed to produce the component. Each of these steps requires energy that must be taken into account. 

According to a study published in Science Direct, “3.43 MJ of electricity is needed to produce 1 kg of LDPE” (Leppäkoski et al.).  Based on this information and the assumption that the plastic packaging weighs roughly 5g, it can be calculated that it takes roughly 17,150 Joules of energy to produce enough LDPE for one ice pack. Additionally, each ice pack is branded with the company's design for the product. Information about the specific paint used by Frosty Tech was unavailable, but since most LDPE is painted with acrylic, it is safe to assume that they likely use this in their manufacturing process as well. Acrylic paints “contain about 41% water, 32% polymer binder, and 6.5% pigments plus additives” (Iscen, Forero-Martinez, Valsson, Kremer). The exact production process for acrylic paint is very in depth and could be a life cycle assessment in itself, and for the purposes of this paper, this process must be considered even though it will not be detailed. It is also critical to address that since the LDPE and acrylic is likely produced off-site, Peloton Shepherd industries must transport these raw materials to their production facilities, requiring gasoline for their transportation.

Each chemical found in the gel of EnviroIce packs is likely outsourced to a different manufacturer and each has a specific production process, which will be explored in this assessment. There were varying levels of information about the production process depending on the chemical. 

Urea, which makes up 0 to 50 parts or 0 to 168g of the product, according to the patent, is manufactured through the “Bazarov reaction, in which carbon dioxide (CO2) and ammonia (NH3) are first converted to ammonium carbamate…which is then dehydrated to urea” and has a high energy demand of ≥24.8 GJ/t (Ding et al.). Based on this information, it is reasonable to calculate that it takes roughly 0 to 4,166,400 J to produce enough urea for a 340g EnviroIce pack. In terms of the acquisition of the required ammonia and CO2, both compounds require other processes before they are ready to be used for urea production. There are several methods for CO2 capture including “pre-combustion, post-combustion and oxyfuel with post-combustion” (“Capturing CO2”). This means that there is even more energy required to capture the CO2 to begin with, and there is additional energy from producing ammonia, as discussed in the Raw Materials section.

Finding information for the energy requirements of the production processes for potassium nitrate (4 to 30 parts), ammonium phosphate (1 to 10 parts), and sodium nitrate (0 to 50 parts) was more difficult, but the mechanisms for their production are known. According to the EcoInvent database “For industrial applications, potassium nitrate is produced by neutralizing nitric acid with potassium hydroxide derived from potassium chloride”  and “The production of ammonium nitrate phosphate involves the combination of liquid ammonia with nitric acid and rock phosphate, using heat and electricity.” Additionally, EcoInvent also writes that for sodium nitrate, “Important methods…[include] the reaction of tail gases from nitric acid plants with sodium hydroxide or sodium carbonate solution.” While more information was unavailable, both processes clearly require heating and reacting different chemicals together, and it can be assumed that this is quite energy intensive. Additionally, the energy needed for the raw materials acquisition for each of the compounds must be taken into account, considering that each of the formative chemicals must be created before their use in production of the compounds for the gel ice pack. 

Ammonium nitrate, which makes up 50 to 95 parts of the gel in the EnviroIce packs, is a salt of ammonia and nitric acid that is largely used for fertilizers. It requires “about 8 million BTU/ton N in addition to the energy required to produce the ammonia (total of 50 million BTU/ton N)” (Davis, Blouin). With that information in mind, it can reasonably be calculated that it takes roughly 8,862,000 – 16,787,687 J of energy to produce enough ammonium nitrate for one EnviroIce pack. It must also be considered that nitric acid and ammonia must be acquired to make the production of ammonium nitrate possible. Nitric acid is produced through “high-temperature catalytic oxidation of ammonia” (“AP42 8.8 Nitric Acid Production.”), meaning that it requires fossil fuels to create a high enough temperature for the reaction. The acquisition of ammonia is discussed above in the production of urea. 

Product Manufacturing 

After considering each of the raw materials that goes into the EnviroIce packs, it is clear that the manufacturing process for this product is quite energy intensive and requires many different raw materials, all of which are virgin. On the Frosty Tech website, the company writes “We have eight manufacturing sites across the US, located in California, Texas, Missouri, Georgia, Ohio, New Jersey, Arizona and Illinois.” Since this product is manufactured and distributed within the United States, where most manufacturing energy comes from natural gas and fossil fuels, it must be noted that the manufacturing process and its energy intensity largely detracts from the overall sustainability of the product.

Though I could not find any specifics on how the ice packs themselves are manufactured, some assumptions about the process can be made based on the components of the product. It can be assumed that the LDPE and the gel material components are all transferred to the gel pack manufacturing plant, during which the chemicals are combined and sealed in the LDPE lining, and potentially printed with the EnviroIce logo. These processes all require machinery and energy to run that machinery, and though the specific data is not available, it must still be taken into consideration in the overall embodied energy of the product. 

Another unique aspect of the raw materials needed for the success of this product is the fact that it must be stored in a cold storage facility so that it remains cold and ready for use by consumers at any time. Cold storage facilities have very high energy demands, as it must power many technologies to keep the product cold. Cold storage facilities use roughly 25 kWH per square foot annually and are on average 20,000 to 60,000 square feet (Weyers). Assuming that Pelton Shepherd and Frosty Tech have a mid-sized cold storage facility of 40,000 square feet, it can be reasoned that they may use around 100,000 kWH yearly per storage facility. That is roughly 10 times more than the average U.S. household uses in one year (EIA). 

Transportation and Distribution

The last factor that must be considered in the embodied energy for this product is the cost of transportation. Based on the available information, it seems that the distribution of EnviroIce is limited to the United States, where most large-scale transportation is provided by semi-trucks that get roughly 6-8 miles to the gallon. The different chemicals needed for the transportation of the materials to the manufacturing sites as well as the distribution of the product to the consumer must be considered when accounting for the fuel it takes to allow the product to be successful. 

Another factor to consider is the last-mile transportation to get the product to the user must also be considered, whether that is in a shipping container being delivered to a customer’s house or the customer’s vehicle if they are picking up the product. With this in mind, the overall sustainability of the product is impacted by the fuel necessary for the transportation of the product. 

Use and Reuse 

It is also critical to take into account the energy used during the use cycle of the product. How much energy they require is dependent on how the product is used. For example, with its intended use as a single-use ice pack used for transportation and shipping of cold products, the EnviroIce pack does not need much added energy during the use phase, as it is merely keeping products cold during shipping. However, if the customer chooses to reuse the ice pack, the energy needed to store the product in the freezer must be taken into account. If the customer chooses to reuse the product and freeze it again, it is important to consider that for one day, the average modern freezer will use “between 30 and 100 watts of power depending on size, indoor temperature & efficiency” (Energy Use Calculator). This amount of energy and raw materials used for maintaining the coolness of the product must be considered as well.  Additionally, if the consumer chooses to use the product as intended and dilute the gel in the ice pack to fertilize plants, there is a need for human energy to perform this action and the energy needed to acquire the water needed to dilute the gel into fertilizer. 

Waste Management 

There is human energy required to dispose of the product correctly in the form of watering plants and recycling the LDPE packaging. In terms of disposal, the actual energy that it takes to either transport the product to the landfill or recycling plant, depending on how the customer chooses to dispose of the product despite its intent, must also be considered. Additionally, there is energy needed to physically process either the waste of the LDPE or recycle the plastic that varies from plant to plant. It can be safely assumed that there is a considerable amount of gasoline needed to transport the waste of this product, but not quite as much as the initial transportation.

  With all of these estimations and rough calculations in mind, it can be estimated that the embodied energy for one EnviroIce Gel Pack involves at a minimum 21 MJ of fossil-fuel based electricity, gasoline for semi trucks to transport the product within the United States and to waste or recycling centers, human energy in the use phase, and at least 100,000 kWh annually for the cold storage centers. While the EnviroIce gel packs are relatively eco-friendly in their disposal, the embodied energy required for sourcing and producing them must be taken into account when evaluating the overall sustainability of the product. 

Waste and Pollution

Material Sourcing

During the materials sourcing process of the production of EnviroIce Gel packs, there are several stages within the process in which waste and pollution are emitted. The type of waste varies from solid, liquid, and gaseous emissions. 

The production of urea produces not only greenhouse gasses emitted by the fuel needed for the machinery, but also other wastes in the form of inert gasses, which are “discharged after recovery of ammonia by condensation” (Cherimissinoff). Additionally, solid waste may occur in the form of solid urea spillage in and around the prilling tower of the manufacturing plant (Cherimissinoff). These gasses can be harmful to the atmosphere and surrounding environments. 

Producing ammonia nitrate also produces solid and gaseous pollution. According to ScienceDirect, “Ammonia emissions take place from the neutralization section. Dust emissions originate from lime stone grinding, granulation, drying, screening and cooling operations” (Cherimissinoff). Also, the machinery needed to produce the chemical also release greenhouse gases into the atmosphere.

Nitric acid also releases greenhouse gasses along with “Tail gas mainly containing oxides of nitrogen (NOx) is released continuously from the absorption tower stack” (Cherimissinoff). Sulfuric acid production releases gasses as well:  “The off gas from the absorption tower stack contains sulphur dioxide, sulphur trioxide (SO3) and acid mist and is continuously discharged” (Cherimissioff). During the production of phosphoric acid, “Considerable quantity of rock phospate dust is emitted from the rock handling and grinding section,” along with a byproduct of gypsum which is often pumped into a gypsum pond. (Cherimissinoff). 

During the production of ammonium phosphate, “ Emission of ammonia takes place from the neutralization section. Dusts originate from granulation, drying, screening and cooling operations” (Cherimissinoff). 

Overall, there are several different solid, liquid, and gaseous pollutants that are released during the production and sourcing of all of these raw materials. While I could not find direct information of the exact type or amount of greenhouse gas emissions, it can safely be assumed that their emission is caused by the production and sourcing of each of these raw materials. 

Processing and Manufacturing

During the processing and manufacturing process, there is a large emphasis on the emission of greenhouse gasses as pollutants from the process of combining all the raw materials for the gel into one compound as well as placing them into their LDPE casing and sealing them. It was assumed earlier that the production process is largely dependent on coal and other fossil fuels, which emit greenhouse gasses. Seeing as greenhouse gasses contribute largely to climate change, their emission is an important factor to consider in the overall waste and pollution impact of the EnviroIce gel pack. 

Distribution and Transportation

The distribution process for EnviroIce gel packs is also very energy intensive, which means that it is also very pollutant emitting. For example, it can be assumed that Pelton Shepherd industry uses semi-trucks to transport their product. This means that they rely on gasoline, which emits CO2 and other toxins into the atmosphere. Additionally, this product has the unique feature that it must be kept cold, meaning that they must use a cold-storage facility to store the products while they are waiting for distribution. As discussed in the embodied energy section, one of these facilities uses roughly 100,000 kWh annually to power the facility (Weyers). Producing 1kWh of electricity with coal produces 820 gCO2e/kWh of CO2, which means that just one facility likely produces roughly 82,000 kgCO2e/kWhCO2 annually (Planet Energie). 

Additionally, the supplemental products that might accompany the ice pack itself must be considered. For example, if the ice packs are transferred on wooden pallets, those must be dealt with as waste or reused for more shipping. Similarly, the ice pack may come with a printed manual which could be considered waste as well, depending on how the consumer chooses to handle it. The product is likely either wrapped in a film to keep it on the pallet or shipped in cardboard boxes, which are all things that must also be taken into consideration when considering the waste in the distribution and transportation process. 

Use and Reuse

During the use and reuse phase, there is arguably the least amount of emissions, considering that how the product is used and potentially reused largely depends on the decisions of the consumer. This means that if the user chooses to simply throw the plastic packaging or entire ice pack away, there is the factor of solid waste in the form of the ice pack and its components. If they choose to recycle it, there is no waste in the use cycle, and if they use the fertilizer gel as intended, there is also no solid waste. 

As mentioned above, if the consumer uses the ice pack as intended as a single-use shipping aid, then the waste depends on how they dispose of the product. However, if they choose to reuse the product, the pollution from generating the energy needed to keep the ice pack frozen must be taken into consideration. Since most fridges and freezers are likely powered by natural gas or fossil fuels, which also release greenhouse gasses into the atmosphere. 

Waste Management

In the waste management phase of the product, the biggest place for emissions is likely the greenhouses gasses from the fossil fuels used to transport the waste to the facility as well as the machinery used to sort and process the plastic waste. Again, this depends on if the LDPE packaging is recycled or landfilled by the consumer, as those processes likely have different energy requirements.  

References

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