Sedimentation is a fundamental step in the water purification process. Its principle is based on the effect of gravity. When raw water is stationary or flowing slowly, suspended particles in the water that are denser than water, such as silt and rust, gradually settle to the bottom under the continuous pull of gravity. This process can be carried out in large sedimentation tanks or sedimentation basins. By controlling the water flow rate and residence time, the particles are given sufficient opportunities to settle, thus removing a large number of visible impurities and preliminarily clarifying the water quality.

Filtration technology further improves the degree of water quality purification. Common ones include sand filtration, activated carbon filtration, and ultrafiltration. Sand filtration uses granular media with different particle sizes, such as quartz sand, to fill the filter bed. When water passes through, tiny suspended particles are trapped by the pores between the sand grains, playing a role in fine filtration. In addition to its physical filtering effect, the rich microporous structure inside activated carbon enables it to have a powerful adsorption capacity, which can effectively remove organic pollutants, odor-causing substances, and some residual chlorine in the water. Ultrafiltration relies on ultrafiltration membranes. These membranes have a specific pore size range, allowing water molecules and small molecular substances to pass through while blocking macromolecular organic substances, colloids, bacteria, etc., removing tiny impurities while retaining the beneficial mineral components in the water.

Reverse osmosis technology can be regarded as one of the core technologies in the field of water purification. It is based on the characteristics of semi-permeable membranes. By applying a pressure higher than the osmotic pressure of the raw water on one side of the membrane, water molecules are forced to pass through the semi-permeable membrane against the direction of the osmotic pressure,