Sewage and wastewater are both dirty water to be discarded, but the degree of pollution is different. The nature and concentration of pollutants are random, and there is no standard to refer to. Only by gaining experience through practice can we master the laws of nature and the laws of sewage change.

Modern treatment methods are divided into three categories: physical method 2, chemical method 2, physical chemical method 3, biological method 3; the degree of treatment is divided into three levels: 1. The degree of treatment; after the suspension is filtered, the particles, colloids and organic solutes decompose 2,3. Deeper removal of residues.

The nature and type of wastewater vary, and corresponding methods can be taken, but chemical and physical methods are the closest for users with small discharges: first, the colloid rapidly chemically decomposes to produce flocs dispersed in the water, followed by the physical changes of adsorption between the flocs, forming particles and precipitating, separating the pollutants in the water.

II. Provisions:

Pollutants come from a variety of components, solids, turbidity, chromaticity, pH value, etc., which constitute the concentration level of wastewater. Due to the lack of necessary space, high-concentration wastewater cannot be treated even with more drugs, but it increases the saturation of substances. Therefore, in the pretreatment test, the high and low concentrations are first adjusted to ensure that the treatment mechanism meets the best conditions, which not only effectively but also reduces the consumption of chemicals.

Example 1: With a large septic tank, the late start of centralized sewage and sewage collection together with light, and both nature and water have been adjusted.