the diagram shows a simple system that turn dirty water into clean water.

Question

The diagram illustrates a system which turns dirty water into clean water.

Generally, the structure of system is quite simple which is called waster-filter system.

Beginning with structure of system. There are two drums in each system and each drum has a different assignment. Drums make up of plastic barrel and each drum has a plastic lid to cover above of drum. The first drum contains sand, charcoal and gravel. They are arranged from bottom to middle or two-thirds of drum. The gravel is arranged at the bottom, followed by the charcoal and finally the sand. Assignment of the second drum is storage. Two drums are combined by a pipe which water flows.

Turning to operating of system. Firstly, dirty water is poured into the first drum and then water flows through three layers. A thing must be note, the first drum must be located higher than the second drum to create pressure. Pressure pushes water to storage and it is called drinking water.