Commonly Used Professional Terms in Circulating Water Treatment

Analysis of commonly used professional terms in the field of chemical water treatment:

1. Recirculating water

A system that uses water to cool process media is called a cooling water system.

 

2. Once-through cooling water system

Cooling water passes through the heat exchange equipment only once; after use, the water is discharged.

 

3. Open recirculating water

Water is used to cool and remove heat generated by process media or heat exchange equipment. Then, part of the hot water is evaporated by direct contact with air, and most of the hot water is cooled before being reused in a cycle.

 

4. Closed recirculating water system

Also known as a closed-loop cooling water system. In this system, the cooling water is not immediately discharged after use but is recovered and reused.

 

5. Cooling tower

A device that uses water as a circulating coolant to absorb heat from a system and release it into the atmosphere to lower the water temperature. It is divided into two cooling methods: natural ventilation and mechanical ventilation.

 

6. Water distributor

The return water is evenly distributed onto the packing material through the water distributor.

 

7. Packing material

The return water passes through the packing material to form a water film, increasing the contact area with the air.

 

8. Water collector

Collects the liquid water carried in the partially evaporated water vapor.

 

9. Circulating water volume

Refers to the total circulating water volume of the cooling towers in the circulating water system. n50 Water retention: The sum of all water volumes in the circulating water system, equal to the sum of the basin volume and the volume of water in the pipes and water-cooled equipment.

 

10. Makeup water volume

Water needed to replenish the circulating water system due to evaporation /blowdown/splash losses.

 

11. Side stream filtration water volume

The amount of water diverted from the circulating cooling water system, treated as required, and then returned to the system.

 

12. Evaporation water volume

The amount of water lost due to evaporation in the circulating cooling water system during operation.

 

13. Blowdown water volume

The amount of water that needs to be discharged from the circulating cooling water system under a certain concentration factor.

 

14. Wind and leakage loss water volume

The amount of water lost due to wind and leakage in the circulating cooling water system during operation.

 

15. Makeup water volume

The amount of water replenished to compensate for losses in the circulating cooling water system during operation.

 

16. Concentration factor

The ratio of the salt concentration of the circulating cooling water to the salt concentration of the makeup water.

 

17. Heat exchange

The exchange of heat between objects is called heat exchange. There are three basic forms of heat exchange in circulating water: heat exchange, convection, radiation, and evaporative heat exchange.

 

18. Heat conduction

The phenomenon of heat transfer between different parts of directly contacting objects is called heat conduction.

 

19. Convective heat exchange

In a fluid, heat transfer between fluids is mainly due to the movement of the fluid, causing part of the heat in the hot stream to be transferred to the cold fluid. This heat transfer method is called convective heat exchange.

 

20. Radiative heat exchange

Part of the thermal energy of a high-temperature object is converted into radiant energy and emitted outward in the form of electromagnetic waves. After reaching the receiving object, the radiant energy is converted back into thermal energy and absorbed. This method of heat transfer by electromagnetic waves is called radiative heat exchange.

 

21. Evaporative heat exchange

A form of heat exchange where water molecules carry away latent heat of vaporization during evaporation.

 

22. Cooling water inlet and outlet temperature difference

The temperature difference between the cooling tower inlet and the water pool outlet.

 

23. Wet-bulb temperature

The air temperature at which water vapor in the air reaches saturation under the same enthalpy air state.

 

24. Dry-bulb temperature

The temperature measured by a thermometer in ordinary air, which is the air temperature often reported in weather forecasts.

 

25. Physical cleaning

Cleaning debris from pipes using water flow.

 

26. Chemical cleaning

Using chemicals to keep the surface of metal heat exchangers clean and activated, preparing for pre-filming.

 

27. Pre-filming

Also known as chemical conversion film, it is a type of protective layer on the surface of metal equipment and pipes, especially pipes that have passed acid washing and passivation, which can be protected by pre-filming.

 

28. Corrosion inhibitor

The process of inhibiting or slowing down the corrosion of metals.

 

29. Scale inhibitor

The process of preventing the formation of deposits on the heating surfaces of heat exchange equipment using chemical or physical methods.

 

30. Oxidizing biocide

A biocide with strong oxidizing properties, usually a strong oxidizing agent, with a strong killing effect on microorganisms in water.

 

31. Non-oxidizing bactericides

They do not kill microorganisms through oxidation, but by poisoning specific parts of microorganisms. Therefore, they are not affected by reducing substances in water.

 

32. Available chlorine

Refers to the amount of chlorine with equivalent oxidizing capacity in chlorine-containing compounds (especially as disinfectants), which can quantitatively represent the disinfection effect.

 

33. Residual chlorine; Residual chlorine refers to the available chlorine remaining in the water after chlorination and a certain contact time.

 

34. Combined chlorine

Refers to the compounds of chlorine and ammonia in water, including NH2Cl, NHCl2, and NHCl3. NHCl2 is more stable and has a good bactericidal effect, also known as combined residual chlorine.

 

35. Free available chlorine

Refers to ClO-, HClO, Cl2, etc., in water. It has a fast bactericidal speed and strong bactericidal power, but disappears quickly, also known as free available chlorine.

 

36. Orthophosphate

In phosphate +5 valent phosphorus.

 

37. Organophosphorus

Contains carbon -phosphorus bonds or organophosphorus acid derivatives containing organic groups.

 

38. Total iron

Iron in various forms, including all iron elements.

 

39. Total zinc

Zinc in various forms, including all zinc elements.

 

40. Chemical retention time

The effective time of chemicals in the circulating cooling water system.

 

41. Scaling

The dissolved calcium and magnesium bicarbonates in water decompose upon heating, precipitating white sediment, which gradually accumulates and adheres to the container, forming scale.

 

42. Corrosion

Refers to the process of loss and destruction (including metals and non-metals) under the action of surrounding media (water, air, acids, alkalis, salts, solvents, etc.).

 

43. Biofilm

A sticky substance formed by microorganisms and their secreted mucus, mixed with other organic and inorganic impurities, adhering to the surface of objects.