Question

In a factory, holes need to be drilled in steel to manufacture car parts. While doing this, the drill and steel get very hot due to friction and this can damage both. To solve this problem, a mixture of oil and water is sprayed onto the drill bit. The mixture acts as both a coolant and a lubricant. At the end of the process, there is a waste mixture of fine steel bits, dirty oil and water. To avoid wastage and pollution, it is advisable to separate the waste mixture and reuse the components.

Answer these questions.
1. Suggest two methods of removing the bits of steel from the waste mixture in order to recycle them.
2. How can the oil and water be separated?

Answer 1

1. We can remove the bits of steel from the waste mixture in order to recycle them:
(i) By filtration
(ii) By using a magnet

2. Oil and water are two immiscible liquids. They form two separate layers in solution, the oil comes on top of solution and water remains on the bottom of the surface. By simply pouring the oil from the container, we can separate water and oil.