The basic knowledge of environmental protection water treatment is all here!

1. Noun explanation

1, raw water: refers to the natural water without any treatment or urban tap water, also called raw water.

2, clarified water: remove the suspended impurities in the raw water water.

3, demineralized water: refers to the Yang, anion in the water basically removed or reduced to a certain degree of water called demineralized water. The methods of salt removal include distillation, electrodialysis, reverse osmosis, ion exchange and so on.

4, turbidity: refers to the turbidity of the water, it is because the water contains a certain amount of suspended substances (including colloidal substances) caused by the optical effect. Units are expressed in NTU. Turbidity is one of the main characteristics to determine whether water is polluted in appearance. The standard unit of turbidity is specified as 1 degree turbidity composed of 1mgSi02.

5, flocculant: can cause colloidal condensation bridge and flocculation of the agent.

6, total alkalinity: refers to the total amount of substances that can neutralize strong acids in water.

7, acidity: refers to the total amount of substances that can neutralize strong alkali in water.

8, hardness: refers to some metal ions that are easy to form precipitates in water, usually referring to calcium and magnesium ion content.

9, conductivity: is the conductivity of the solution between two parallel electrodes with a cross-sectional area of 1 square centimeter and a distance of 1 centimeter at a certain temperature. It can indirectly indicate the content of dissolved salt in water.

10, resistivity: is also an indicator that reflects the electrical conductivity of water, the greater the resistivity of water, the worse the electrical conductivity of water, the less ions contained in water. Its common unit is mω.cm. It has an reciprocal relationship with the conductivity. For example, if the conductivity of water is 0.2μs/cm, its resistivity is 1/0.2=5(mω.cm).

11, TDS(total dissolved solids) : is the remaining inorganic after filtering out suspended solids (SS) and colloids and evaporating to see all the water. The unit is ppm or mg/l and can be measured with a TDS meter. It also reflects the amount of ions in the water. There is a rough correspondence between it and the conductivity: for a sodium chloride reference solution, a TDS value of 1ppm corresponds to a conductivity of 2μs/cm.

12, pH value: the relative content of acid and base in the solution. pH is a measure of the negative logarithm (log) of the concentration of hydrogen ions in water. The pH value is divided into 0~14 blocks, and the pH value is 7.0, the water is neutral; If pH is less than 7.0, water is acidic. pH value is greater than 7.0. Water is alkaline.

13, alkalinity: alkalinity refers to the content of substances in water that can accept the neutralization reaction of [H+] ions with strong acids. The substances that produce alkalinity in water are mainly carbonate alkalinity from carbonate and bicarbonate alkalinity from bicarbonate, and hydroxide alkalinity from the presence of hydroxide.

14, SDI: Pollution index - used to measure the amount of suspended solids in the raw water used in the reverse osmosis system.

15, ozone: an unstable, highly active form of oxygen, it is produced by natural lightning or high voltage charge through the air, is an excellent oxidizing agent and disinfectant.

16, residual chlorine: water after chlorination disinfection, contact for a certain time, the effective chlorine left in the water.

17, Total Escherichia coli: Total Coliform group refers to a group of aerobic and facultative anaerobic, at 37℃ growth can make lactose fermentation, within 24 hours to produce acid and gas gram-negative bacillus. Total Coliform is the number of total coliform bacteria per liter of water sample.

18, recovery rate: refers to the ratio of the flow of product water produced by the system to the flow of water.

19, desalting rate: reflects the performance of the membrane parameters, usually a primary RO membrane system desalting rate of more than 97%. It can be simply calculated: (raw water conductivity - electrical conductivity of product water)/ raw water conductivity.

20, salt content: The salt content of water, also known as salinity, is the number of salts contained in the water. Since various salts in water generally exist in the form of ions, the salt content can also be expressed as the sum of the amount of various cations and the amount of anions in water.

21, precipitation: one of the technical methods of wastewater treatment. It can be divided into two kinds of physical precipitation and chemical precipitation. The precipitation usually referred to is physical precipitation, that is, the method of gravity separation.

22, water: a variety of explanations, sewage engineering is called recycled water, the factory is called reuse water, generally differentiated by water quality. Mainly refers to urban sewage or domestic sewage after treatment to reach a certain water quality standards, can be reused in a certain range of non-drinking water.

The quality of reclaimed water is between the upper water (drinking water) and the water (domestic sewage), which is also the origin of the name of the water, and people will supply the water system is called the water system.