What's the difference between pure water and fresh water?

According to the research results of contemporary science and technology, it is known that the total water resources of our planet are about 65.438+38.6 million cubic kilometers, but fresh water only accounts for 2.5% of the total water resources. It is about 35 million cubic kilometers. However, 69.5% of the total fresh water resources in the world, that is, about 24 million cubic kilometers, are difficult for human beings to use, such as glaciers, permanent snow, ice in the eastern strata and other solid forms. About 30% of fresh water resources are groundwater, and only a very small part of them can be used by human beings. No wonder people of insight exclaimed: the next niche facing mankind will soon be the shortage of fresh water resources! Simply put, this is an incomparably huge and deep ocean on our planet, which stores as much as 65.438+33.8 million cubic kilometers of seawater, accounting for about 96.5% of the total water resources of the earth. Therefore, relying on modern scientific and technological means to fully develop seawater voluntarily is the only way and hope for mankind to overcome the global shortage of fresh water resources.

Pure water is common water after electrodialysis, which greatly reduces the original mineral content in the water, and at the same time, it is disinfected and sterilized to make the water "pure water".

Electrodialysis engineering is one of the separation projects using membrane technology, and its principle is the process of partially separating electrolyte ions from solution by ion migration through selective ion exchange membrane under the action of DC electric field.

Main uses:

1. producing purified water

2. Desalination of seawater and brackish water

3. Defluorination and wastewater treatment

4. Desalination of power equipment water supply

Typical technological process of electrodialysis engineering

1. Salt water desalination and groundwater defluorination

Raw water → 10 1 filter → precision filter → electrodialysis device → hollow fiber ultrafilter → ultraviolet sterilizer → finished water.

2. Production of drinking pure water and space water

Raw water → mechanical filter → activated carbon filter → precision filter → electrodialysis device → cation exchanger → anion exchanger → mixed ion exchanger → hollow fiber ultrafilter → ultraviolet sterilizer → ozone sterilizer → finished water.

3. Water for injection and infusion in pharmaceutical industry

Raw water → activated carbon filter → precision filter → electrodialysis device → cation exchanger → anion exchanger → mixed ion exchanger → multi-effect distiller → finished water.

4. Water for chemical fertilizer and machinery industry

Raw water → mechanical filter → precision filter → electrodialysis device → cation exchanger → degassing tower → anion exchanger → finished water.

Ozone is now recommended for disinfection of pure water. After ozone disinfection, there is no residue.