Course:SPPH381B/TermProject/The Red Solo Cup
Introduction
The red solo cup is a polystyrene cup. It is characteristically red however it can be found in many other colours. It can hold 18 oz. of liquid and has ribbed edges to help grip. It was introduced to America in the 1970s with the goal of minimizing cleaning for hosts of events as the cup can be disposed of after use[1]. The Red Solo Cup was developed by the Solo Cup company which was bought by Dart in 2012. Dart is responsible for the “development, manufacturing and distribution of innovative foodservice packaging solutions”[2]. The primary component of the cup is polystyrene. The polymer is synthesized from its monomer styrene and is then formed into the well know cups that are essential for any party or summertime barbeque. The process of creating a Red Solo Cup begins with the extraction of resources, in this case petroleum. The crude compounds are then used to form styrene and eventually the polymer polystyrene[3]. At the end of this process, polystyrene is in pellet form and is sold to Dart Container Company which forms the polystyrene via extrusion and thermoforming[4]. Once the cups have been formed they are distributed across North America by DTX Trucking, a fleet owned by Dart[5]. Upon reaching its destination, the cups are bought by consumers, and are eventually recycled, where they are processed at a recycling plant. Throughout all these processes, occupational nurses care for the workers and play a critical, yet unknown part in the manufacturing of a Red Solo Cup[6].
Extraction
Exploration
The process of creating a red solo cup begins with the extraction of petroleum from the ground. Before the drilling and extraction of a well begins, it must be found. This is the job of geologists, who apply their knowledge of rock formation and the application of various tools to find the well[7]. They use technology such as satellite imaging, sonar, and, most commonly, seismology. Seismology involves the passage of shock waves through rock which are then reflected to the surface and are measured by seismic equipment [7].Geologists are then able to determine the location of a deposit as oil reflects the waves differently than solid rock[7].
Drilling
Once the potential well has been found, it is up to the drilling team to dig down to the oil. The placement of the drill site on the surface depends on the nature of the potential formation to be drilled, the characteristics of the surface, and the depth and size of the target deposit[8]. The drilling process involves the creation of multiple holes that form a single well, some of these holes will be used to pump water, chemicals, and pressurized steam into the wells to aid in extraction[7].
Extraction
Extraction involves three steps, primary, secondary, and tertiary extractions. The primary extraction involves natural mechanisms, such as pressure and gravity, that displace the oil, once natural pressure falls secondary extraction begins[7]. This process involves the injection of liquids, gases, or air into the well to increase pressure; the familiar pumpjack is used in secondary extraction[7]. Finally, tertiary extraction employs heat and chemicals to ease the flow of oil and extract it from the earth[7]. The total oil pulled from the well is typically 50 to 60% of the total petroleum in the deposit; the entirety of the deposit is not extracted as the energy returned will not be equal to energy invested[7]. The decision to drill a well and how much oil to extract is therefore dependent on the economic potential for that well[8].
Hazards of Oil and Gas Extraction
Primary Manufacturing
The primary manufacturing of the Red Solo Cup involves the transformation of the crude oil and other materials into styrene and its polymer polystyrene. Styrene is very reactive and readily undergoes homopolymerization when initiated by strong acids and peroxides[9]. The process begins with ethyl benzene that is converted to crude styrene, and then to its final product, polystyrene[9].
For the production of 1kg of high impact polystyrene[10]:
| Input Parameters | Value |
|---|---|
| Non-renewable materials | - |
| - Minerals | 6.2g |
| - Fossil fuels | 1.910kg |
| - Uranium | 0.004g |
| Renewable materials | 4.294g |
| Water Use (not including cooling water) | 10.279kg |
| Renewable materials | - |
| - For energy | 40.8 Mega Joules |
| - For feedstock | 46.4 Mega Joules |
| Output Parameter | Value |
|---|---|
| CO2 | 2.8kg |
| Particulate matter | 0.98g |
| Non-hazardous waste | 0.056kg |
| Hazardous waste | 0.028kg |
Feed Solution Tank
A known quantity of styrene is taken into the feed tank, and various chemicals are added. These chemicals include zinc stearate and liquid parafin, as internal lubricants, and toners, to give colour to the product[9]. These chemicals are then agitated to ensure proper mixing and will be passed through filters into kettles to remove undissolved particles[9].
Pre-polymerization
The mixture is pumped from the feed tank to the kettles and initiators are added to promote polymerization of styrene, this mixture is kept at 120-140⁰C and 550mmHg. Nearly half the styrene conversion to polystyrene takes place during this step[9].
Polymerization
The styrene solution is now transferred into towers that are kept at 210⁰C to encourage further polymerization[9].
Preheating and Devitalization
The preheating and devolitization process is maintained at 200-300⁰C and 740mmHg, in this process the vaporized material is condensed and the liquid is collected in a separate tank, this liquid is condensed once again and is then sent to be separated from unwanted contaminants[9].
Extrusion & Palletisation
The product is now cut into 3-by-3 mm sized pellets under circulating water, dried, and screened for over- and under-sized product[9].
Hazards of Working in the Plastic Manufacturing Industry
Secondary Manufacturing
Dart Container Company receives the pelletized polystyrene and these parts then goes through the extrusion and thermoforming processes to form the cup. Extrusion is the process of converting a raw material, polystyrene in this case, into a product of uniform shape and density, the process dates to the 1930s[11]. Once the uniform product has been formed, it is shaped through a process call thermoforming in which thin, hot, solid sheets are subjected to pressure so that they undergo deformation into moulds to become thin-walled structures[12].
Extrusion
The extrusion process is completed with a single screw extruder. This device has three sections, the feed section, compression section, and metering section[13]. The material in the feed section will be mostly solid, with the material melting as it moves towards the metering section, this melting occurs due to the frictional heat generated against the screw and due to heat conducted from barrel heaters[13]. Once the melted pellets arrive at the metering section they are pumped out of the screw through a die[14]. For the formation of a cup the molten plastic goes through a sheet die, with a thickness of 0.25 to 5mm and a width up to 3 meters[15]. Cooling of these sheets involves a three-roll stack that are cored with circulating water for cooling and the pressure between the rolls forms the material ejected from the screw into a sheet[15].
Thermoforming
The next step in the formation of the cup is thermoforming, this process takes the sheet produced by the extrusion process and forms it into the desired shape. Workers load the rolls of plastic sheets into the thermoforming machine, when the machine is started, the sheets are advanced into the oven for heating and forming[16]. The sheet is clamped to the edges of the mould and is heated which causes the sheet to expand and sag into the mould[12]. The heat is then removed and pressure is applied to the sheet within the mould, pressure is maintained as the sheet cools, once cooled, the pressure is removed and finally the structure is removed from the mould[12]. The last stage of this process occurs when the structure is advanced to the trim station[16]
Hazards of Thermoforming Machine
Transportation
Once the cups have been manufactured, they are packaged and shipped to various locations across North America. Dart Container Company has a private fleet, DTX trucking, which distributes Dart products[5]. Commercial trucking has a major importance in most of the developed world, in the United States, the annual revenue from commercial trucking is more than $500 billion and the industry employs nearly 10 million people[17].
Hazards in the Trucking Industry
Recycling
The Red Solo Cup has now made its way to a consumer, once they are done using it, the cup can be put in the recycling bin where it will be collected and recycled. In 2009, 61 million tons which accounts for 25% of municipal solid waste was recovered through recycling in the United States and 74% of this was collected via curbside pickup[18]. The recyclable material is collected from households and then is transported to a materials recovery facility where it is sorted and processed before being sent to manufacturers[18]. The process of recycling an object so that it may be reused by a manufacturer involves drivers to collect the recyclables, sorters, plant managers, technicians, and mechanics[18].
Drivers and Collection
The collection process involves curbside pickup of recycling and transport to materials recovery facilities, these workers often work in teams, one worker drives the truck while the other grabs and empties the curbside bin into the truck, or operates hydraulic lifting mechanisms[18]. 72,500 individuals, or 25% of all workers in the solid waste industry are refuse and recyclable materials collection workers and they experienced 36% of the total fatalities[19]. Risks associated with curbside pickup are heavy lifting, limited visibility around the vehicle, lack of visibility and communication among the workers, and infectious and hazardous waste[20].
Hazards with Rear-Loading Trucks
Sorters
Sorters are responsible for separating the recyclables so that they can be processed. They work along conveyer belts and remove unwanted materials such as waste or paper products from a plastic stream, for example[18]. Today, this job is mostly performed by automated equipment as it is faster, however, sorters must still ensure that stray objects do not end up in the wrong place and they monitor the waste stream[18].
Mechanics, Technicians, and machine maintenance
Mechanics and technicians are essential to inspect and repair machinery in the materials recovery facilities and maintain recycling trucks[18]. They are tasked with regular inspections of all the machinery and diagnostic tests and preventative maintenance of the trucks[18]. They may also be required to make emergency roadside repairs if the recycling trucks experience problems while on a collection route [18].
Infrastructure
Occupational nurses are healthcare workers who provide services to employees at workplaces such as industrial plants, service companies, universities, research laboratories, and divers public institutions or private enterprises[21].
Hazards of Working as an Occupational Nurse
References
- ↑ https://thump.vice.com/en_us/article/history-of-red-solo-cup
- ↑ https://www.dartcontainer.com/about-us/faqs/
- ↑ http://www.inclusive-science-engineering.com/high-impact-polystyrene-manufacturing-process/
- ↑ http://www.brighthubengineering.com/manufacturing-technology/77254-the-extrusion-thermoforming-process-made-easy/
- ↑ 5.0 5.1 https://www.dartcontainer.com/ca/jobs-careers/career-areas/trucking/
- ↑ https://www.osha.gov/Publications/QandA/osha3160.html
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 http://www.petroleum.co.uk/location-and-extraction
- ↑ 8.0 8.1 http://naturalgas.org/naturalgas/extraction/
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 9.7 http://www.inclusive-science-engineering.com/high-impact-polystyrene-manufacturing-process/
- ↑ http://www.plasticseurope.org/Documents/Document/20100312112214-FINAL_POLYSTYRENE_GPPS_111209-20090428-003-EN-v1.pdf
- ↑ Sauceau, M., Nikitine, C., Rodier, E., & Fages, J. (2007). Effect of supercritical carbon dioxide on polystyrene extrusion. The Journal of Supercritical Fluids, 43(2), 367-373
- ↑ 12.0 12.1 12.2 Warby, M. K., Whiteman, J. R., Jiang, W. G., Warwick, P., & Wright, T. (2003). Finite element simulation of thermoforming processes for polymer sheets. Mathematics and computers in simulation, 61(3), 209-218
- ↑ 13.0 13.1 Rauwendaal, C. (2014). Polymer extrusion. Carl Hanser Verlag GmbH Co KG
- ↑ Chung, C. I. (2000). Extrusion of polymers. Hanser, Munich
- ↑ 15.0 15.1 Xanthos, M., & Todd, D. B. (1996). Plastics processing. Kirk-Othmer Encyclopedia of Chemical Technology
- ↑ 16.0 16.1 https://www.osha.gov/SLTC/etools/machineguarding/plastics/thermoform_machine.html
- ↑ http://onlinepubs.trb.org/onlinepubs/circulars/ec117.pdf
- ↑ 18.0 18.1 18.2 18.3 18.4 18.5 18.6 18.7 18.8 https://www.bls.gov/green/recycling/#occupations
- ↑ https://www.cdc.gov/niosh/docs/2012-140/pdfs/2012-140.pdf
- ↑ Englehardt, J. D., Fleming, L. E., & Bean, J. A. (2003). Analytical predictive Bayesian assessment of occupational injury risk: municipal solid waste collectors. Risk analysis, 23(5), 917-927
- ↑ http://ilo.org/wcmsp5/groups/public/---ed_protect/---protrav/---safework/documents/publication/wcms_192435.pdf