Sewage effect

Pollution movement process:

Various movements occurred immediately after the pollutants entered the water body. Take the ocean as an example for a brief introduction, and the situation of other bodies of water can be analogized.

The residence time of pollutants in seawater τ can be calculated as follows:

τi = Ai/dAi/d t

Where Ai is the total amount of pollutant i discharged into the water body, and dAi/dt is the deposition rate of pollutant i in the ocean. In general, the greater the activity of pollutants in seawater, the shorter the residence time.

The enrichment process of pollutants in the ocean mainly depends on the physical and chemical enrichment settlement such as adsorption and the selective absorption of the food chain, the result is that the pollutants are removed from the sea water, so that the latter is purified, and will be harmful to organisms to varying degrees, and will increase the accumulation of pollutants in the bottom material, which may cause secondary pollution of the sea water.

Hazards to aquatic life

There are many kinds of aquatic animals and plants in nature. There is a complex exchange of matter and energy between living things and water, and between living things and living things, and a dynamic balance relationship is maintained from the quantity. But under the influence of human activities, this balance has been disrupted. When humans discharge pollutants into the water, some beneficial aquatic organisms will be poisoned and die, while some pollution-resistant aquatic organisms will intensify reproduction, consume a large amount of oxygen dissolved in the water, and make beneficial aquatic organisms forced to migrate to other places due to lack of oxygen, or die. In particular, some toxic elements are difficult to dissolve in water and easy to accumulate in living organisms, causing great harm to humans. For example, the content of mercury in water is very low, but the content in aquatic organisms is very high, and the content in fish is surprisingly high. It is assumed that the concentration of mercury in the water body is 1, the concentration of mercury in the benthos of aquatic organisms (refers to the small organisms living in the bottom mud of the water body) is 700, and the concentration of mercury in the fish is as high as 860. It can be seen that when the water body is polluted, on the one hand, the balance between living things and water, living things and living things is destroyed, on the other hand, some toxic substances continue to transfer and enrich, and finally endanger human health and life.

Quartz sand filtration

Quartz sand filtration is one of the most effective means to remove suspended matter in water, and it is an important unit in sewage advanced treatment, sewage reuse and water supply treatment. Its role is to further remove the pollutants that have been flocculated in the water, and it achieves the purpose of water purification through the interception, sedimentation and adsorption of the filter material.

1. For industrial water, domestic water and municipal water supply systems requiring effluent turbidity ≤5mg/L to meet drinking water quality standards;

2. Removal of suspended matter and solid matter in industrial sewage;

3, can be used as ion exchange softening, desalt system in the pretreatment equipment, water quality requirements are not high industrial water raw filtration equipment;

And used in swimming pool circulation treatment system, cooling circulation water purification system, etc.

Water pollution effects:

The harm of water pollution is multifaceted, here is a brief introduction to the impact of water pollution on human health.

● Causes acute and chronic poisoning. Water contaminated by toxic and harmful chemicals can cause poisoning through drinking water or the food chain. The famous Minamata disease and Itamata disease were caused by water pollution.

● Carcinogenic effect. Some carcinogenic chemicals such as arsenic, chromium, nickel, beryllium, aniline, benzo (a) pyrene and other polycyclic aromatic hydrocarbons, halogenated hydrocarbons polluted the water body, can be adsorbed by suspended matter, sediment, can also accumulate in aquatic organisms, long-term drinking water containing such substances, or eating organisms with such substances accumulated in the body (such as fish) may cause cancer.

● Occurrence of water-borne infectious diseases. Human and animal feces and other biological pollutants pollute the water, which may cause bacterial intestinal infectious diseases such as typhoid, dysentery, enteritis, cholera, etc. Common intestinal viruses such as spinal gray matter viruses, Coxsackie viruses, infectious hepatitis viruses, etc., can cause corresponding infectious diseases through water pollution. The "hepatitis A incident" in Shanghai in 1989 was caused by water pollution. In developing countries, about 60 million people die each year from diarrhoea, most of them children.

● Indirect effects. After water pollution, it can often cause the deterioration of sensory properties of water. For example, although some pollutants have no direct harm to human health at a certain concentration, they can cause water to have heteroodor, heterocolor, foam and oil film, etc., which hinder the normal use of water. Copper, zinc, nickel and other substances at a certain concentration can inhibit the growth and reproduction of microorganisms, thus affecting the decomposition and biological oxidation of organic matter in the water, reducing the self-purification capacity of the water body, affecting the health of the water body.