WEEK 6

 PRODUCT LIFE CYCLE ♺ & CRADLE TO CRADLE DESIGN 🌱

This week was another synchronous lesson with Dr Noel where we learnt about the Product Life Cycle and Cradle to Cradle Design. In week 4 & 5’s lessons, we learnt about the different types of materials that can meet the requirements of our product and also how we can change the design of a product to use another material to improve the product as a whole. We learnt that materials will need to fulfil the physical properties to allow the desired product we designed to function correctly and effectively. In this week’s lesson, we learnt about the various environmental impacts certain materials have on the ecosystem and how we can establish a balance between the physical properties and sustainability during our material selection to help ensure our product is eco-friendly yet performs effectively.

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These are some Generic Design Considerations/Principles we were introduced to briefly during this week’s lesson:

• Use energy efficient processes

•  Make the product last longer.

• Design for reuse and recycling. (for example: easy to disassemble)

•  Consider product life cycle

• Shift from personal ownership to shared ownership

• Buy from nearby sources

 ♺ What is product life cycle? 

A typical product life cycle consists of 6 stages, starting off with the raw materials and ending when the product reaches its end of life also known as the disposal stage. 

Product designers make use of a technique known as the Life Cycle Analysis or Life Cycle Assessment (LCA) to investigate the environmental impacts associated with all 6 the stages of a product's life :

1. raw material extraction through materials processing -> BIRTH🥚
2. manufacturing
3. packaging
4. distribution
5. use, repair and maintenance -> GROWTH 🐣🐔
6. disposal or recycling -> DEATH 👻

For ease of understanding, Dr Noel taught us this concept by asking various classmates to identify various stages of a paper's life cycle based on the image he showed us. He then taught to us associate the 6 stages of the product life cycle with Birth, Growth and Death (as above) similar to a life cycle of a living organism.  We learnt that the purpose of learning product life cycle was for us to essentially understand -> sustainable development. As we know that the resources on earth is finite so the materials we chose for our product must be sustainable and eco-friendly. In order to find out if the materials used are deemed sustainable we use:  product life cycle. 

Next he taught us -> Cradle to Grave System.

💣What is Cradle to Grave System? 

Essentially, most of the product life cycle falls into the Cradle-To-Grave product system. 

This means from the stage of Raw materials,  it will go to the landfills. The system minimizes the negative impact on the environment through the 3 R's which are Reuse, Reduce and Recycle. However, Cradle-To-Grave is not very effective in terms of the method recovery. 

Here was when Dr Noel introduced us to instead ->  Cradle-To-Cradle Design.

🌱 What is Cradle 2 Cradle Design? 

Cradle-To-Cradle design is a biometric approach to the design of products and system that emulates nature's processes, modelled after Nature where the cycle has a closed loop with no end.

In this Design, old materials are reused to make new ones while reducing the number of raw materials being extracted. The biological cycle is a type of cradle-to-cradle design that consists of:

1. Production 🔨
2. Product 📦
3. Use Phase✂
4. Bio-degradation ♨
5. Biological nutrients 🍃
6. Plants🌱

Cradle 2 Cradle Design has 3 principles essentially seeking to completely remove waste through the design:

• Firstly, nutrients become nutrients again whereby for example a tree leaf falls to the ground, degrades and becomes food for other organisms. 

• Secondly, Use of renewable energies whereby systems are powered by renewable energy such as solar and wind. Moreover, use of renewable energy has no long-term impact on the environment compared to the use of fossil fuels. 

• Lastly, celebrating diversity. For example: different systems integrate to make use of one another's waste for the benefit of their own system giving rise to an overall decrease in waste produced by both systems.

Dr Noel asked various classmates to screenshare when they visited a few websites that demonstrate the 3 principles above used by companies to help us further understand how the principles work.

💥Activity

1. Applying the Product Life Cycle to our Product - Portable Food Heater

Table 1: 6 Stages of Product Life Cycle of a Portable Food Heater

Stage 1: Raw Materials or Extraction	v  Plastic is chosen as the material for the outer part of the portable food heater as plastic is an insulator of heat and when users hold the food heater or open it to put their food in the heater to heat it, users will not be scalded. §  Although Plastics have a low melting point, typically the maximum heating temperature of a food warmer will not exceed that of the plastic’s melting point e.g., HDPE (high density Polyethylene’s melting point: 130.8°C). This is because the food is merely being heated and the temperature at which the food is being heated cannot be too high if not it will either scald the consumer’s mouth or it will take too long to cool which is not favorable to the consumer. Thus, Plastic can be used as an external insulating material.)           v  Metal (stainless steel) is chosen as the material for the inner heating part of the heater as metals are the best conductors of heat and will be efficient in supplying the greatest amount of heat to heat the food the fastest so consumers will not have a long wait.
Stage 2: Manufacturing	v  Manufacturing Plastics (HDPE, material for outer part of heater) Raw material: Petroleum. -          Petroleum reservoirs can be found beneath land or the ocean floor. Their crude oil is extracted with giant drilling machines. -          HDPE is made under controlled conditions by applying intense heat to petroleum. This process, also known as “cracking,” helps create ethylene gas. During its production, the gas molecules will attach to form polymers, which then produce polyethylene. -          After this process, the polyethylene will have a sludgy appearance, but after it’s put through a series of molds, it forms into granules. Once the molding process is complete, a strong polymer material HDPE is formed for the outer component of the heater.   v  Manufacturing Metal (stainless steel for internal heating part of heater) Raw material(s): iron ore, chromium, silicon, nickel, carbon, nitrogen, and manganese. (Stainless Steel is an Alloy)   - Metals are extracted from the Earth’s Core while gases like nitrogen can be obtained from fractional distillation of air.   1) Melting and casting  The raw materials are first melted together in an electric furnace. This step usually requires 8 to 12 hours of intense heat. When the melting is finished, the molten steel is cast into semi-finished solid forms. These include blooms (rectangular shapes), billets (round or square shapes 1.5 inches or 3.8 centimeters in thickness), slabs, rods, and tube rounds. 2) Forming Next, the semi-finished steel goes through forming operations, beginning with hot rolling, in which the steel is heated and passed through huge rolls. Blooms and billets are formed into bar and wire, while slabs are formed into plate, strip, and sheet. 3) Heat treatment  After the stainless steel is formed, most types must go through an annealing step. Annealing is a heat treatment in which the steel is heated and cooled under controlled conditions to relieve internal stresses and soften the metal. 4) Cutting  Cutting operations are usually necessary to obtain the desired blank shape or size to trim the part to final size. Mechanical cutting is accomplished by a variety of methods. Stainless steel can also be cut using flame cutting, which involves a flame-fired torch using oxygen and propane in conjunction with iron powder. This method is clean and fast. 5) Finishing Surface finish is an important specification for stainless steel products and is critical in applications where appearance is also important. A smooth surface as obtained by polishing   v  The heating element are inserted in between the outer plastic layer and the inner metal layer. v  Electromechanical components are installed to control the time taken to heat up food and prevent overheating.
Stage 3: Packaging	v  The product is packaged into boxes and wrapped with bubble wrap to prevent the product from being damaged when being transported.
Stage 4: Distribution	v  The products are transported to dealers, distributors, shops in many countries to be sold to consumers via Shipping or Land Transport modes like Trucks. v  Ware housing and retailing are also considered as part of this stage.
Stage 5: Use	v  Product main use is to heat food on the go. Allowing users to have the ability to heat up food even when they are outside the comfort of their homes.
Stage 6 Disposal:	v  Reuse: the heating element can be removed for other uses such as             to boil water. v  Reuse: Electromechanical components can be given a second life in ovens or microwaves. v  Recycle: Stainless steel/ metal can be extracted and use as raw                     materials for various processes. -          Recycle: HDPE can be recycled and be used to remanufacture other plastic products -          HDPE is accepted at most recycling centers in the world, as it is one of the easiest plastic polymers to recycle. Most recycling companies will collect HDPE products and take these to large facilities to be processed. -          First, the plastic is sorted and cleaned, to remove any unwanted debris. The plastic then needs to homogenized, so that only HDPE will be processed.  -          HDPE is then shredded and melted down to further refine the polymer. The plastic is then cooled into pellets which can be used in manufacturing. v  Disposal: products end up in landfills or incinerators.

 References:

Madehow.com. 2021. How stainless steel is made - material, manufacture, used, processing, parts, components, structure, steps. [online] Available at: <http://www.madehow.com/Volume-1/Stainless-Steel.html> [Accessed 27 May 2021].

AZoCleantech.com. 2012. Recycling of High-Density Polyethylene (HDPE or PEHD). [online] Available at: <https://www.azocleantech.com/article.aspx?ArticleID=255> [Accessed 27 May 2021].

Scranton Products. 2021. How Is HDPE Made? | Scranton Products. [online] Available at: <https://www.scrantonproducts.com/how-is-hdpe-made/#:~:text=HDPE%20is%20made%20under%20controlled,polymers%2C%20which%20then%20produce%20polyethylene.> [Accessed 27 May 2021].

2. Applying Cradle to Cradle Design to our Product - Portable Food heater

• Make important parts such as the heating element and the timer dismantlable and sell separately so that consumers will not have to buy a new product when one of the parts is broken which reduces the use of materials.     

•  Use of renewable energy sources- in the extraction of raw materials such as metal and plastic, heat is used to melt the materials to form into shapes easy for transportation. This heat usually comes from the burning of fossil fuels to provide heat energy to melt this materials. Instead of using fossil fuels, use renewable energy such as solar energy to power the heater to melt these materials.