The Industrial water should meet the needs of the production, the quality of the industrial water must be ensured after the treatment with the water treatment agent, meanwhile, it must has no side effects which will result in the production damage and the equipments faults. So, different industrial water has the different requirements to the water treatment agents, the provisions of the certain index of the water treatment agent are regulated. The regulations are normally not issued by the State Department as the formal specification, they are usually some technical reference and data as the reference, which are combined with the limitation under the specific circumstances in practice.

1.Raw Water
Mainly refers to the water in the beverage manufacturing industry, the foodstuff manufacturing industry, the electrolysis water, the medicines and the pharmaceutical manufacturing industry etc.
1.1 The quality of the water used in the beverage and foodstuff manufacturing industry requires the same level as the day life drinking water. There is a special case in the brewing industry: with the consideration of the influence on the cicrobial fermentation processing, the calcium and the magnesium as the nutrient material should have a certain amount; Cl- promote the saccharification at around 50mg/L, No2 below 0.2, while No3 at around 5-25 mg/L.
1.2 In the electrolysis industry, the medicines and the pharmaceutical manufacturing industry, it requires the water with low salt content, and with the least iron and manganese, so it is better to use the pure water.

2. The water in the production technics
In the light industry and the chemical industry: the sugar making, the paper making, the textile, the dyeing, the synthetic fiber industry and the organic synthesis industry etc. In the production process, the water itself does not come into the final product, but its ingredients may enter into the product and influence the quality of the final product. The water for the sugar making is required to contain the organic compouns, the nitrogen compounds and the bacteria as less as possible. The refined sugar usually requires the pure water. In the paper making process, different grades of the paper product require the different water quality. The burbidity, the chroma, the iron, the manganese, the calcium and the magnesium will affect the smoothness and the color of the paper product, the chloride and the salt content will affect the moisture absorption capability of the paper product. In the dyeing industry and the textile industry, it has the higher requirements on the hardness and the iron content in the water, the sediment generated by the iron may weaken the strength fo the fiber, it will also cause the dye decomposition and the reduction of the color brightness of the fiber.

3.The water in the production process
The water does not enter into the product, it is only used to wash the surface or only has the general contact on the product, mostly it has very little influence to the quality of the product. There is no common water quality requirement on this kind of water, different quality standards depend on the specific application.
3.1 In the oil field flooding: the water is required to have no deposit, which will not block the oil layers.
3.2. In the plating cleaning water: no deposited spots on the metal surface, so it requires the hardness, the metal iron contents and the solid salt contents to be as lower as possible.

4. The boiler water
According to the boiler’s pressure and the temperature, there are different requirements to the water, higher requirements on the hardness will easily generate the scale, while the dissolved oxygen will result in the corrosion to the equipment. The oil will produce the bubbles and will promote the generation of the scale. The free Co2, the PH value, the salt content, the alkalinity, Cl- and CiO2 etc are related to the scaling, the corrosion and the foam etc.
For the industrial boiler, the steam is used as the heat source or the general powder, so most of the industrial boilers are of low pressure boiler, the requirements to the water quality is lower. For the power plant boiler, the steam is used to drive the turbine, so most of such boilers are of high pressure or even ultra high pressure, meanwhile with the consideration of the deposition of the scaling and the corrosion problems, the requirements to the water quality is very strict.

5.The cooling water
The basic requirements are: the water temperature should be as low as possible and will not change severely with the climate change; will not general scale and the dirt clogging etc which may block the piping line; does not have the corrosion to the metal; will not reproduce the microorganisms and the biologics etc. There is no unified standard, the general consideration includes the algae, the microbes, the suspending solids, the hardness salts, the dissolved gas, the organic matters, the acid and the grease etc.

6.The pure water and the ultra pure water
The pure water refers to the water which has been desalted deeply, generally it includes the desalted water, the pure water and the ultra pure water. The pure water is also called the deionized water or the deep desalting water, the salt content is reduced to below 1.0mg/L, the electrical conductivity is decreased to 1-0.1μΩ/cm.

The ultra pure water and the ultra pure water is the water which has been not only done the further salt removing, but also with the least amount of the water gas, the colloid, the organic matter, the bacteria and other kinds of impurities, the salt content is reduced to below 0.1mg/L, while the electrical conductivity is decreased to 0.1μΩ/cm.