Practical 1

 Reverse Engineering⚡

In week 3, our group completed our very first practical together! Woohoo!!

In this practical, we were exploring how the coffee machine shown in the picture works! We were given a scenario and was tasked to reverse engineer a coffee maker to better understand the operating principles and propose ways to reduce energy consumption!

There were 4 crucial steps in our experiment.

1. Dismantling the Coffee Maker

2. Analysing the internal components of the Coffee Maker

3. Making sense of the principles used to function this machine.

4. Use Chemical Engineering principles to improve the Coffee Maker.

1. Opening and Exploring the Coffee Maker💪

We first unscrewed the coffee maker and removed the various parts: lid, filter, filter holder, water tank cover and mug.

2. What Exactly is in the Coffee Maker?👀

The main parts that heat up the water are: U-tube and the Heating element.

On top of the heating element, we figured that there are other key components in the coffee maker that facilitates the whole operation. 

3. How do all these parts come together?💫

Well, the way this machine is made is actually rather simple!

Let's take a look at this drawing.

Water flows down and levels out within the coffee machine when water is added to the reservoir. The tubing runs pass the heating element, which is responsible for both heating the water and the plate where the jug/ pot sits on. When the coffee maker is being switched on, the heating element carries out its function, heating!! Water is being heated up.

This is were the magic happens! The water in the heated tubing starts boiling, causing some of the liquid to change into vapour phase. Vapour being more buoyant than liquid, the fluid will be able to rise up the tube carrying liquid up! The water eventually reaches the shower head and hot water is dispensed onto the coffee power and leaching occurs.

Coffee starts dripping into the pot and that's how when we start smelling the strong aroma of the coffee!

4. How can we Improve?💡

We had to find ways to increase the energy efficiency. Meaning we had to fully utilise the energy being used!

We started another experiment to find out how much energy was used in the process.

Next we had to do our mass balance since Leaching is a separation process, and all separation includes mass transfer!

we even measured the mass of filter paper to optimise the energy used.

Unfortunately, our practical did not derive us at a solution. We took in back to class for further brainstorming and research.

We concluded 2 ways to improve energy usage.

One way to reduce the amount of heat loss is to insulate the heating element that is not in contact with the metal plate and U-tube (water inside being heated). This ensure that minimum heat is being loss to external environment, instead is used to heat the water in U-tube or the metal plate to keep warm.

Another way to increase efficiency is to reduce the air between the heating element and the metal plate. Which helps to reduce heat resistance. This is to ensure that heat produced will be only for heating the water or keeping the brewed coffee warm and not be loss to the surroundings.

This concludes our very first practical together. It was definitely a success!💥