For this week I have come up with three main concepts for my project.
The first idea I have was for a shell separator. This can be used after a sheller has been used to separate all of the shells away from the nuts.
The principle behind it I tested out. First I had the idea to see if water would separate the nuts from the shells. I found out that the nuts only sink after a few hours and if left in too long the shells start to sink as well.
Then the idea came to me to use a milt-teared shaker box to separate the shells from the nuts. To test out my idea I took about 30 hand shelled peanuts and put the shells and the nuts into the same container. Simply by shaking the container the bigger shells went to the top and the nuts went to the bottom with some fine shell bits. By making a device that has different size grids will allow only the peanuts to get trapped in the middle.
1. Shows peanuts and shell right after shelling (mixed)
2. Shows peanuts at the bottom after shaking the container side to side.
3. Shows the nuts at the bottom after removing the top layer of shells
My second idea is to create a hand powered drum separator. Inspired by designs that are used to wash laundry in an oil drum I realized a modified version could be ideal for separating nuts from the shells quickly.
It works using the same principles as the shell separator, but using centrifugal force to separate the shells from the nuts instead of side to side movement.
I also discovered by using a garlic roller that too much force by rolling the nuts can easily break the nuts into many pieces. This is also one of the issues that some current solutions have when shelling peanuts.
Using a propane tank to try to shell the peanuts demonstrated that with a solid bottom surface the nuts shatter
My third idea is for a shelling device. I discovered that grids are one of the best ways to separate the shell from the nuts without damaging most of the nuts. By using a heavy weight on top of a wooden box filled with peanuts the peanut will be forced through the grate at the bottom. Simply by shaking the box side to side the weight will force the peanuts through the grate.
With using a cookie cooling rack I also proved that a grid is a great way to remove peanuts from the shells.
Most nuts were seperated from their shell by using the grate.
There are a few things with my concepts that will be breaking points.
Any of my three concepts will have to be able to maintain the integrity of the peanut and not crush the peanut.
The grates will have to be ridged and not have an extreme amount of flex in order to shell/separate the nuts. To my knowledge they don’t have many ways of separating the shells from the fine shell bits. If they already have a better way of doing this that will be a breaking point. If any of my designs cannot be manufactured in Kasese, Uganda will be a breaking point.
Over the next week I want to design preliminary prototypes I want to build and test to test some of the breaking points.
Also I would like to review the ethics application.