Water treatment professional terms, involving chemical water treatment, circulating water treatment, sewage treatment and other fields of water treatment, the author through many years of water treatment work experience summary, edited 180 water treatment professional name analysis, some names for the author according to experience explanation, only for reference!

Chemical water treatment

1. Surface water; It refers to the water existing on the surface of the earth's crust and exposed to the atmosphere. It is the general name of four kinds of water bodies, namely rivers, glaciers, lakes and swamps, also known as "land water".

2. Groundwater; It refers to the water stored in the pores below the vadose zone (the vadose zone refers to the geological medium below the earth surface and above the water table), including the rock pores, fractures and caves. Groundwater exists in the crustal rock fractures or soil pores.

3. Raw water; It refers to the water collected in nature, including but not limited to groundwater, reservoir water and other natural sources, without any artificial purification.

4、PH； It is the value of pH of solution, pH = - LG [H +], that is, the negative value of the logarithm of the concentration of hydrogen ion.

5. Total alkalinity; The total amount of substances that can neutralize strong acids in water. Such substances include strong base, weak base, strong base and weak acid salt.

6, phenolphthalein alkalinity; It is the alkalinity measured with phenolphthalein as indicator (titration end pH = 8.2-8.4).

7. Alkalinity of methyl orange; It is the alkalinity measured with methyl orange as indicator (titration end pH = 3.1-4.4).

8. Total acidity; Acidity refers to the total amount of substances in water that can neutralize with strong base, including inorganic acid, organic acid, strong acid and weak base salt, etc.

9. Total hardness; In general natural water, the main ions are Ca2 + and Mg2 +, and the content of other ions is very small. Generally, the total hardness of water is the total content of Ca2 + and Mg2 +.

10. Temporary hardness; The hardness formed by the presence of Ca (HCO3) 2 and Mg (HCO3) 2 in water can be removed after boiling. This hardness is called carbonate hardness, or temporary hardness.

11. Permanent hardness; The hardness formed by the presence of salts such as CaSO4 (CaCl2) and MgSO4 (MgCl2) in water can not be removed after boiling. This hardness is called non carbonate hardness or permanent hardness.

12. Dissolved matter; It exists in the form of simple molecules or ions in the solution of water (or other solvents). The particle size is usually only a few tenths to a few nanometers. It is not visible to the naked eye, and there is no dingdar phenomenon. It cannot be seen with an optical microscope

13. Colloid; The size of the clusters of molecules or ions is usually tens of nanometers to tens of microns, which is not visible to the naked eye, but the phenomenon of dingdal occurs. The small colloidal particles can not be seen by optical microscope, but the large ones can be seen

14. Suspended solids; It is a small particle formed by a large number of molecules or ions. Its size is usually more than tens of microns. It can be clearly seen by optical microscope. Suspended particles can be precipitated after standing for a long time.

15. Total salt content; The total amount of ions in water is called total salt content. The unit is expressed in mg / L (ppm in the past).

16. Turbidity; Also known as turbidity. From the technical point of view, turbidity is a water quality substitute parameter to reflect the content of suspended solids in water. The main suspended matter in water is generally soil. The unit of standard turbidity is 1mg silica in 1L distilled water, which is expressed as 1ppm.

17. Total dissolved solids; TDS, also known as the total amount of dissolved solids, is measured in mg / L (mg / L). It indicates how many mg of dissolved solids are dissolved in 1 l of water.

18. Resistance; According to Ohm's law, when the water temperature is constant, the resistance value r of water is inversely proportional to the vertical sectional area F of the electrode, and is directly proportional to the distance L between the electrodes.

19. Conductivity; The conductivity of water is called conductivity s (or conductivity).

20. Conductivity; The conductivity of water is the reciprocal of the resistance of water, which is usually used to express the purity of water.

21. Resistivity; The resistivity of water refers to the resistance between the opposite sides of a 1cm cube of water at a certain temperature. Its unit is Ohm * cm. It is generally a parameter indicating the quality of high purity water.

22. Softened water; It refers to the water whose hardness (mainly refers to calcium and magnesium ions) is removed or reduced to a certain extent. During the softening process, only the hardness of water decreases, but the total salt content remains unchanged.

23. Desalted water; It refers to the water whose salts (mainly strong electrolytes dissolved in water) are removed or reduced to a certain extent. Its conductivity is generally 1.0-10.0 μ The resistivity (25 ℃) is 0.1-1000000 Ω· cm, and the salt content is 1.5mg/l.

24. Pure water; It refers to the strong electrolyte and weak electrolyte (such as SiO2, C02, etc.) in water. Remove or reduce water to a certain extent. Its conductivity is generally 1.0-0.1 μ S / cm, resistivity 1.0-1000000 Ω. Cm. The salt content is less than 1mg / L.

25. Ultra pure water; It refers to the water in which the conductive medium in water is almost completely removed, and the non dissociated gases, colloids and organic substances (including bacteria) are also removed to a very low level. Its conductivity is generally 0.1-0.055 μ S / cm, resistivity (25 ℃) > 10 × 1000000 Ω. Cm, salt content < 0.1mg/l. The ideal pure water (theoretically) conductivity is 0.05 μ 3 S / cm at 25 ℃ × one million μ s/cm。

26. Deaerated water; Also known as deoxidized water, to remove dissolved oxygen in water, generally used for boiler water.

27. Ion exchange; It is a method to separate the exchangeable groups in the ion exchanger and the different ion exchange ability of various ions in the solution.

28. Cation resin; It has acid group. In aqueous solution, acidic groups can ionize to form H +, which can exchange with cations in water.

29. Anion resin; They are ionized in aqueous solution and exchange with anions.

30. Inert resin; No active groups, no ion exchange, the relative density is generally controlled between the anion and cation resin, to separate the anion and cation resin, avoid the cross pollution of anion and cation resin in regeneration, and make the regeneration more complete.

31. Microfiltration; MF, also known as microporous filtration, belongs to precision filtration. Microfiltration can filter out micron or nanometer particles and bacteria in the solution (official account: Pump housekeeper).

32. Ultrafiltration; UF is one of the membrane separation technologies driven by pressure. The pore size of the membrane is between 20 and 1000 a ° for the separation of macromolecules and small molecules.

33. Nanofiltration; NF is a pressure driven membrane separation process between reverse osmosis and ultrafiltration. The pore size of nanofiltration membrane is about several nanometers.

34. Infiltration; Permeation is the diffusion of water molecules through a semi permeable membrane. It infiltrates from high water molecular region (low concentration solution) into low water molecular region (high concentration solution).

35. Osmotic pressure; For the semi permeable membrane with different concentrations of aqueous solution on both sides, the minimum additional pressure applied on the high concentration side in order to prevent water from penetrating from the low concentration side to the high concentration side is called osmotic pressure.

36. Reverse osmosis; RO, reverse osmosis is to artificially pressurize water from concentrated solution to low concentration solution. The pore size of RO reverse osmosis membrane is as small as nanometer. Under a certain pressure, water molecules can pass through RO membrane, while inorganic salts, heavy metal ions, organic matter, colloids, bacteria, viruses and other impurities in source water cannot pass through RO membrane.

36. Dialysis; Also called dialysis. A membrane separation operation driven by concentration difference, which uses the selective permeability of the membrane to solute, realizes the separation of solute with different properties.

37. Electrodialysis; ED is a phenomenon that charged solute particles (such as ions) in the solution migrate through the membrane when dialyzing under the action of electric field, which is called electrodialysis.

38、EDI； Also known as continuous electric desalting technology, it is a pure water manufacturing technology which combines ion exchange technology, ion exchange membrane technology and ion electromigration technology.

39. Recovery rate; It refers to the percentage of feed water converted into produced water or permeate in membrane system.

40. Desalination rate; The percentage of total soluble impurity concentration removed from the influent of the system by reverse osmosis membrane, or the percentage of specific components such as divalent ions or organic matter removed by nanofiltration membrane.

41. Salt permeability; The opposite value of desalting rate is the percentage of dissolved impurities in the influent passing through the membrane. Permeate: purified water produced by membrane system.

42. Flux; The permeate flow rate per unit membrane area is usually expressed as liter per square meter per hour (lgm2h) or square foot per day (GFD).

43. Product water; The purified water solution is produced by reverse osmosis or nanofiltration system.

44. Concentrated water; The part of the solution that passes through the membrane, such as concentrated water from reverse osmosis or nanofiltration systems.

Circulating water treatment

45. Circulating water; The system of cooling process medium with water is called cooling water system.

46. Once through cooling water system; The cooling water only passes through the heat exchange equipment once, and is discharged after use.

47. Open circulating water; The heat emitted by process medium or heat exchange equipment is removed by water cooling, and then part of the hot water is evaporated when the hot water is in direct contact with air, and most of the hot water is recycled after being cooled.

48. Closed circulating water system; Also known as closed circulating cooling water system. In this system, the cooling water is not discharged immediately, but recycled.

49. Cooling tower; It is a device that uses water as circulating coolant to absorb heat from a system and discharge it into the atmosphere to reduce the water temperature. There are two cooling modes: natural ventilation and mechanical ventilation.

50. Water distributor; The return water is evenly distributed on the packing through the water distributor.

51. Filler; The backwater forms a water film through the filler to increase the contact area with the air.

52. Water collector; The liquid water carried in the evaporation steam is recovered.

53. Circulating water volume; It refers to the total circulating water volume of cooling tower on the circulating water system. N50 water holding capacity: the total volume of all water in the circulating water system, equal to the total volume of the pool and the water in the pipeline and water cooling equipment.

54. Make up water; It is used to replenish the water required for the loss due to evaporation / blowdown / splashing in the circulating water system.

55. Side filtration capacity; Part of the water from the circulating cooling water system is treated as required and then returned to the system.

56. Evaporation water volume; Evaporation loss of circulating cooling water system during operation.

57. Sewage volume; The amount of water that needs to be discharged from the circulating cooling water system under the determined concentration multiple.

58. Water loss due to wind leakage; The amount of water lost by blowing and leakage during the operation of circulating cooling water system.

59. Make up water; The circulating cooling water system replenishes the lost water during operation.

60, concentration multiple; The ratio of salt concentration of circulating cooling water to that of make-up water.

61. Heat exchange; The heat exchange between objects is called heat exchange. There are three basic forms of circulating water heat exchange: heat exchange, convection heat exchange, radiation heat exchange and evaporation heat exchange.

62. Heat conduction; The phenomenon of heat transfer between parts of an object in direct contact is called heat conduction.

63. Convection heat transfer; In the fluid, the heat transfer between the fluids is mainly due to the movement of the fluid, so that part of the heat in the heat flow is transferred to the cold fluid, which is called convective heat transfer.

64. Radiation heat transfer; Part of the heat energy of the high temperature object is transformed into radiant energy, which is emitted to the receiving object in the form of electromagnetic wave. After the radiant energy is transformed into heat energy and absorbed, this way of electromagnetic wave transferring heat is called radiation heat transfer.

65. Evaporation heat transfer; A form of heat transfer in which the latent heat of vaporization is taken away by evaporation of water molecules.

66. Temperature difference between inlet and outlet of cooling water; The temperature difference between the cooling tower inlet and the pool outlet.

67. Wet bulb temperature; It refers to the air temperature when water vapor reaches saturation under the same enthalpy air state.

68. Dry bulb temperature; It is the temperature measured by the thermometer in the ordinary air, that is, the temperature often said in our general weather forecast.

69. Physical cleaning; The debris in the pipe is cleaned out of the pipe through the flow rate of water.

70. Chemical cleaning; The surface of the metal heat exchanger is kept clean and activated by the action of the reagent to prepare for the pre membrane.

71. Premembrane; Chemical conversion coating is a kind of protective coating on the surface of metal equipment and pipeline, especially the pipeline after pickling and passivation, which can be protected by pre coating.

72. Corrosion inhibitor; The process of inhibiting or delaying the corrosion of metal.

73. Scale inhibitor; Using chemical or physical methods to prevent the heating surface of heat exchange equipment from producing deposits.

74. Oxidizing bactericide; Biocide with strong oxidation, usually a strong oxidant, has strong killing effect on microorganisms in water.

75. Non oxidizing bactericide; It doesn't kill microorganisms by oxidation, but causes toxic effects on special parts of microorganisms. Therefore, it is not affected by reducing substances in water.

76. Available chlorine; It refers to the amount of chlorine in chlorinated compounds (especially as disinfectants) with the same oxidation capacity, which can quantitatively express the disinfection effect.

77. Residual chlorine; Residual chlorine refers to the effective chlorine remaining in the water after chlorination and contact for a certain period of time.

78. Combined chlorine; It refers to the compound of chlorine and ammonia in water, including NH2Cl, nhcl2 and nhcl3. Nhcl2 is more stable and has good bactericidal effect, also known as combined residual chlorine

79. Free residual chlorine; It refers to ClO -, HClO, Cl2, etc. in water. It has fast sterilization speed and strong bactericidal power, but it disappears quickly. It is also called free residual chlorine.

80, normal phosphorus; The + 5 valent phosphorus in phosphate.

81. Organic phosphorus; It is a compound containing carbon phosphorus bond or a phosphoric acid derivative containing organic group.

82. Total iron; Iron in various states of existence contains all iron elements.

83. Total zinc; Zinc in various states contains all zinc elements.

84. Residence time of the reagent; The effective time of reagent in circulating cooling water system.

85. Scaling; Calcium and magnesium bicarbonate dissolved in water are decomposed by heat, precipitating white precipitates, and gradually accumulating on the container (official account: Pump housekeeper), called scaling.

86. Corrosion; It refers to the process of loss and destruction (including metal and nonmetal) under the action of surrounding media (water, air, acid, alkali, salt, solvent, etc.).

87. Biological slime; A viscous substance produced by microorganisms and their mucus, which is mixed with other organic and inorganic impurities and adheres to the surface of an object.

sewage disposal

88. Domestic sewage; It is mainly the discharge water produced by all kinds of kitchen water, washing water and toilet water used in human life. Most of them are non-toxic inorganic salts. Domestic sewage contains more nitrogen, phosphorus, sulfur and pathogenic bacteria.

89. Municipal sewage; Sewage discharged into urban sewage system. The combined drainage system also includes production wastewater and intercepted rainwater. Municipal sewage mainly includes domestic sewage and industrial sewage, collected by the urban drainage network and transported to the sewage treatment plant for treatment.

90. Industrial wastewater; It refers to the waste water, sewage and waste liquid produced in the process of industrial production, which contains industrial production materials, intermediate products and products lost with water, as well as pollutants produced in the process of production.

91、COD； Chemical oxygen demand: the amount of oxidant consumed by the substances that can be oxidized in the water body during chemical oxidation under specified conditions, expressed in milligrams of oxygen consumption per liter of water sample, and is usually recorded as cod.

92、BOD； The amount of dissolved oxygen in water consumed by the process of microbial decomposition of organic matter in surface water is called biochemical oxygen demand, usually recorded as BOD, and the commonly used unit is mg / L.

93. BC ratio; It indicates the biochemical degree of pollutants in water, which is difficult to biochemical from 0.1-0.25, 0.25-0.5, and more than 0.5 is easy to biochemical.

94、TOC； Refers to the total amount of carbon in dissolved and suspended organic matter in water, reflecting the content of organic compounds oxidized in water, unit: ppm or ppb.

95. Ammonia nitrogen; It refers to the nitrogen in the water in the form of free ammonia (NH3) and ammonium ion (nh4+).

96. Organic nitrogen; The general term of nitrogen containing substances bound with carbon, such as protein, amino acid, amide, urea, etc.

97. Kjeldahl nitrogen; TkN refers to the nitrogen content measured by Kjeldahl method. It includes ammonia nitrogen and organic nitrogen compounds which can be converted into ammonium salt under this condition.

98. Nitrate nitrogen; NOx ˉ， Refers to the nitrogen element contained in nitrate. The nitrate is only in harmony with nitrite.

99. Total nitrogen; TN is the total amount of inorganic and organic nitrogen in water.

100. Total phosphorus; TP, the results of the determination after digestion of various forms of phosphorus into orthophosphate were measured in milligrams of phosphorus per liter of water sample.

101. Secondary phosphorus; With H2PO2 ˉ The phosphate in the form can not be removed by normal chemical dephosphorization, and it needs to be converted into sulfuric acid to remove it.

102. Chroma; It refers to the degree of yellow or yellowish brown in the soluble or colloidal substances contained in water.

103. Grating; Used to remove floating objects in water.

104. Initial sedimentation tank; Also known as a sedimentation tank, the sewage treatment is used to remove the structure of the precipitable and floating objects.

105. Regulating pool; A structure used to regulate the flow of inlet and outlet water. It can be used as the regulation of water quantity and water quality, as well as the pH value and water temperature of sewage, and the pre aeration function, and can also be used as accident drainage.

106. Accident pool; Accident water collection tank is a kind of structure needed in the process of sewage treatment. When dealing with high concentration wastewater discharged by some factories such as chemical industry and petrochemical industry, accident pool will be set up generally.

107. Oil separation tank; The purpose of separation is achieved by using different proportion of suspended matter and water in wastewater.

108. Air flotation; A large number of micro bubbles are produced in water, which makes the air attach to the suspended particles in the form of highly dispersed micro bubbles, which causes the density less than water. The principle of buoyancy is used to make it float on the water surface, so as to realize the separation of solid-liquid.

109. Biochemical pool; The field pool where bacteria metabolism is located in biochemical treatment.

110. Secondary sedimentation tank; That is, secondary sedimentation tank, which is an important part of activated sludge system, is mainly used to separate sludge, clarify, concentrate and return the activated sludge.

111. Horizontal flow sedimentation tank; The plane of the pool is rectangular, and the inlet and outlet are respectively set at both ends of the pool length.

112. Vertical flow sedimentation tank; Also known as vertical sedimentation tank, it is a vertical flow of wastewater in the tank. The plane of the pool is circular or square, and the water enters the tank from the top to the bottom by the inlet pipe located in the center of the pool. It is precipitated by the weight of sludge itself.

113. Amplitude flow sedimentation tank; The wastewater enters the pool from the inlet pipe in the center of the pool, and flows slowly along the radius direction to the pool. The suspended matter settles in the flow and enters the sludge hopper along the slope of the bottom of the pool, and the clarified water overflows from the pool to the water channel.

114. Sludge tank; Generally, it is used to hold the return sludge and the remaining sludge.

115. Monitoring pool; Also known as the clean water tank, it is used to hold the treated sewage.

116. Condensation; The process of colloid losing stability. It is commonly known as colloid desstable.

117. Flocculation; The process of the desstable colloids agglomerating into large particle flocs.

118. Coagulation; The whole process of two stages of forming large particles of flocculate by desstable and flocculation. General name of coagulation and flocculation

119. Metabolism; The exchange of material and energy between the body and the external environment and the self-renewal of material and energy in the organism are called metabolism. Metabolism includes synthetic metabolism (assimilation) and catabolism (dissimilation).

120. Bacteria micelles; Some bacteria are bound together in a certain arrangement, surrounded by a common capsule to form a certain shape of bacterial group, called bacterial micelles, due to their genetic characteristics.

121. Filamentous bacteria; A class of bacteria with filamentous structure. The skeleton of the bacteria.

122. Autotrophic bacteria; Bacteria with inorganic carbon as carbon source

123. Heterotrophic bacteria; Bacteria with organic carbon as carbon source

124. Anaerobic environment; In theory, anaerobic means that there is no molecular oxygen or nitrate nitrogen. But it is impossible to achieve it in practice. Do < 0.2 is anaerobic in engineering,,

125. Aerobic environment; There are both dissolved oxygen and nitrate nitrogen. In the project, do > 0.5 is aerobic.

126. Hypoxia environment; It means that there is no molecular oxygen and nitrate nitrogen. Do in the project is anoxia from 0.2 to 0.5.

127. Activated sludge method; The sewage treatment method is realized by the adsorption, metabolism and mud water separation of bacteria micelles.

128. Biofilm method; The treatment of organic wastewater by microorganisms (biofilm) attached to the surface of certain solid substances.

129. Hydraulic retention time; HRT is a term for water treatment process. Hydraulic retention time refers to the average residence time of wastewater to be treated in the reactor, that is, the average reaction time of the action between sewage and microorganism in bioreactor.

130. Mud age; Mean time of residence of microbial cells in aeration tank. For the activated sludge method with reflux, sludge sludge age is the average time (in days) required for the sludge renewal in the whole tank of aeration tank.

131、SV； 30 minute settlement ratio refers to the rapid pouring of the mixed activated sludge mixture into 1000ml measuring cylinder to full scale. After 30 minutes of static sedimentation, the volume ratio of sludge to the mixture is sludge settlement ratio (%), also called sludge settlement volume (SV30) is shown in ml / L. Since sludge settlement is 30 minutes later, it can reach or close to the maximum density, so it is generally used as the standard time for this indicator.

132、MLSS； Sludge concentration, weight of dry sludge contained in sludge mixture of 1 litre aeration tank

133、MLVSS； The concentration of volatile suspended solid in the mixture represents the concentration of organic solid substance in the activated sludge of the mixture.

134、RSS； Sludge concentration of the return sludge.

135、SVI； Sludge volume index is an indicator to measure the settling performance of activated sludge. Refers to the volume of 1g of dry sludge (in ML) of the mixed liquid in the aeration tank after 30min static sedimentation, namely: svi= sludge volume (ML) / dry weight of sludge (g) after 30 minutes of static sedimentation of the mixture, namely SVI = SV30 / MLSS.

136. Internal reflux ratio; The ratio of the flow rate of nitrification liquid to the inflow flow is generally expressed by percentage, and the symbol is r.

137. External reflux ratio; Also known as sludge return ratio, the ratio of the flow rate of the sludge to the inflow flow. Generally expressed in percentage, the symbol is r.

138. Vaccination; The process of adding activated sludge or granular sludge to the biochemical treatment system.

139. Domestication; In order to make the mature activated sludge of fecal sewage have the ability to treat the specific industrial wastewater gradually.

140. Organic load; It refers to the amount of pollutants removed by activated sludge per unit mass in a unit time.

141. Volume load; Unit aeration tank volume, the weight of pollutants that can be removed in a unit time.

142. Impact load; In the operation of sewage treatment, the sludge volume will always be kept at a certain level, and the volume of reactor (aeration tank, anaerobic reactor, etc.) will not change. But if the influent water quality changes greatly (COD soars or drops sharply), it will make the sludge load and volume load change greatly, which will have an impact on sludge microorganism, which is called impact load.

143、ORP； The redox potential is the measurement index of the redox ability of aqueous solution, its unit is MV.

144、DO； The molecular oxygen dissolved in water is called dissolved oxygen, usually recorded as do, expressed in milligrams of oxygen per liter of water.

145. Aeration; A means of making air and water in strong contact with each other, which aims to dissolve oxygen in the air in water or to expel unnecessary gases and volatile substances into the air.

146. Oxygen filling rate; In wastewater treatment, the aerator's ability to supply oxygen to liquid is called oxygen filling capacity, which is kg/ (M3) ˙ h) It is calculated as [10 ℃ or 20 ℃, 101.3kPa). The oxygen filling capacity of liquid within kilowatt hour is called oxygen filling efficiency.

147. Push flow activated sludge method; The sewage flows evenly, and the wastewater enters from the head end of the tank and flows out from the end of the tank. The liquid flow in the front and the back section does not mix.

148. Sequencing batch activated sludge method; The invention relates to an activated sludge sewage treatment technology which operates by intermittent aeration. Its main feature is the orderly and intermittent operation in operation.

149. Microscopic examination; Abbreviation for microscope examination. It is to sample and make samples to be examined, observe, analyze and judge under microscope.

150. Protozoa; Protozoa is the lowest eukaryotic monocell in the animal world, and the individual is composed of single cells.

151. Postnatal organisms; The general name of all animals except protozoa (metazoa subperions).

152. Non filamentous bacteria expand; The non filamentous bacterial expansion is caused by the accumulation of high viscosity substances (such as glucose, mannose, arabinose, rhamnose and deoxyribose) in the bacteria.

153. Filamentous bacteria expand; The expansion of filamentous bacteria caused by the reproduction of a large number of filamentous bacteria in activated sludge.

154. Peroxide; When the microorganism is full of oxygen and nutrition is insufficient, that is, carbon source in sewage is insufficient, the microorganism will continue to oxidize itself.

155. Exogenous respiration; Under normal circumstances, microorganism uses the energy supplied by the outside world to carry out respiration metabolism called exogenous respiration.

156. Endogenous respiration; If the outside world does not supply energy, it is called endogenous respiration to use the energy materials stored inside itself to carry out respiration metabolism.

157. Aging; The sludge disintegration caused by sludge age is too long, long time and low load or over oxidation.

158. Surplus sludge; It refers to the activated sludge discharged from the secondary sedimentation tank (or sedimentation area) outside the system in the activated sludge system.

159. Ammoniation; It refers to the process of microbial decomposition of nitrogen containing organic matter such as protein and urea to ammonia.

160. Nitrification; It refers to the process of ammonia oxidation to nitric acid under the action of microorganisms.

161. Denitrification; It refers to the biochemical process of bacteria reducing nitrogen (n) in nitrate (NO3 −) to nitrogen (N2) through a series of intermediate products (NO2 −, no, N2O).

162. Short-term nitrification and denitrification; Short-term nitrification refers to the formation of nitrite by NH3, and no longer produces nitrate; N2 is directly produced by nitrite, which is called short-range denitrification.

163. Simultaneous nitrification and denitrification; Nitrification and denitrification often occur in the same treatment conditions and the same treatment space. Therefore, these phenomena are called synchronous nitrification / denitrification (SND).

164. Anaerobic ammonia oxidation; That is, under the condition of hypoxia, anaerobic ammonia oxidation bacteria use nitrite as electron acceptor to oxidize ammonia nitrogen into nitrogen.

165. Chlorination at the folding point; NH3-N in wastewater can be oxidized to chloramine (NH2Cl, nhcl2, NCl3) by chlorine oxidants (such as Cl2 and NaOCl) at the appropriate pH value, and then oxidized to N2 gas for removal.

166. Bird manure stone method; The method of removing ammonia nitrogen and total phosphorus by the precipitation of magnesium phosphate formed by magnesium ion, ammonium ion and phosphate in water.

167. Biological phosphorus removal; The process of phosphorus removal was realized by using the excessive absorption of phosphorus by P.

168. Chemical phosphorus removal; The process of dephosphorization is carried out by the principle of phosphate and some metal ions.

169. Gasification and phosphorus removal; The process of phosphate forming phosphine under the action of microorganisms.

170. Sludge drying; The process of removing most of the water content from sludge by infiltration or evaporation.

171. Anaerobic reactor; A special reactor for anaerobic treatment technology.

172. Anaerobic granular sludge; The granular sludge produced by upflow anaerobic sludge bed and its similar reactor is hollow and nearly round, mainly composed of inorganic sediment and extracellular polysaccharide. Many microorganisms can effectively remove pollutants from wastewater.

173. Aerobic granular sludge; It is a granular activated sludge formed by the self coagulation of microorganisms in aerobic environment.

174、MBR； Membrane bioreactor is a new water treatment technology which is combined with membrane separation unit and biological treatment unit. Replace the secondary sedimentation tank with membrane.

175. Advanced oxidation; The process of oxidation degradation of pollutants in sewage that can not be oxidized by ordinary oxidants is carried out by the production of hydroxyl radicals.

176. Hydroxyl radical; It is an important active oxygen, and it is formed by the loss of an electron by the hydrogen hydroxide (oh-) in molecular formula. The hydroxyl radicals have a strong ability to obtain electrons, i.e. oxidation ability, and the oxidation potential is 2.8V. It is the oxidant second only to fluorine in nature.

177. Evaporation crystallization; Heating evaporation solvent makes solution from unsaturated to saturated, and continues to evaporate, and excess solute will be crystal precipitation, called evaporation crystallization.

178. Salt eating bacteria; A kind of bacteria microorganism with specific physiological structure and can survive only in salt containing environment.

179. Reuse of reclaimed water; It is to treat domestic sewage (or urban sewage) or industrial wastewater through deep technology, remove various impurities, remove toxic and harmful substances and some heavy metal ions that pollute the water body, and then sterilize and sterilize. The water body is colorless, tasteless, and the water quality is clear and transparent, and it meets or is better than the standard (or relevant provisions) of miscellaneous water stipulated by the state, It is widely used in the production of enterprises or the life of residents.

180. Zero emission; Refers to the reuse of industrial water after reuse, the salt content and pollutants in this part are highly concentrated into waste water for recycling and reuse, or the materials that are insoluble in water are filtered out by filter press and recycled for use. No waste liquid is discharged to the factory