Some standard content:
Chemical Industry Standard of the People's Republic of China
HG/T2160-91
Dynamic simulation test method for cooling water
Published on September 16, 1991
Ministry of Chemical Industry of the People's Republic of China
Implementation on January 1, 1992
Chemical Industry Standard of the People's Republic of China
Dynamic simulation test method for cooling water
1 Subject content and scope of application
HG/T2160-91
This standard specifies the scope of application, technical requirements and test methods of dynamic simulation test for open circulating cooling water. This standard is applicable to small-scale dynamic simulation tests of metal (including ferrous and non-ferrous metal) partition-type heat exchange equipment in the laboratory in diffuse circulating cooling water systems, and is also applicable to medium-sized dynamic simulation tests. On-site monitoring of heat exchanger tests can also be used as a reference. 2 Reference standards
GBJ50 Industrial circulating cooling water treatment design specification GB5776 Conventional exposure corrosion test method for metal materials in surface seawater GB6903 General rules for analysis of boiler water and cooling water GB6904.1 Analysis of boiler water and cooling water pH determination glass electrode method GB6905.1 Analysis of boiler water and cooling water Determination of chloride molar method GB6905.3
Analysis of boiler water and cooling water Determination of chloride mercury salt titration method Analysis of boiler water and cooling water water sample collection method GB6907
GB6908
Analysis of boiler water and cooling water Determination of conductivity GB 6909.1
Analysis methods for boiler water and cooling water Determination of hardness High hardness water GB6910
Analysis methods for boiler water and cooling water Determination of calcium Complexometric titration GB6911.1
Analysis methods for boiler water and cooling water Determination of sulfate Gravimetric method Analysis methods for boiler water and cooling water
Determination of sulfate
GB 6912.1
GB 6912.2
Analysis methods for boiler water and cooling water
Determination of sulfate
Barium chromate photometric method
Potentiometric titration method
Analysis methods for boiler water and cooling water
Determination of nitrate and nitrite Nitrate ultraviolet photometric method Analysis methods for boiler water and cooling water
Determination of nitrate and nitrite Nitrite ultraviolet photometric method Determination of nitrate and nitrite, &-naphthylamine hydrochloride photometric method Analysis methods for boiler water and cooling water
GB6912.34
Determination of phosphate Orthophosphate
Analysis methods for boiler water and cooling water
Analysis methods for boiler water and cooling water
Determination of phosphate
Total inorganic phosphorus Phosphate
Analysis methods for boiler water and cooling water
Determination of phosphate
Total phosphate
GB10539
Analysis methods for boiler water and cooling water Determination of potassium ion Flame photometry HG5-1502
Determination method of alkalinity in industrial circulating cooling water HG5—1526
Technical conditions for corrosion test pieces for chemical treatment of cooling water HG5--1600
Analysis methods for scale and corrosion products in industrial circulating cooling water Rules HG5-1601 Investigation, collection and preparation of samples for scale and corrosion products in industrial circulating cooling water HG5-1602 Determination method for water content in scale and corrosion products in industrial circulating cooling water HG5--1603 Determination method of ferrous sulfide content in corrosion products HG5-1604 Determination method of ignition loss in industrial circulating cooling water scale and corrosion products HG5-1605 Content of acid-insoluble matter, phosphorus, iron, aluminum, calcium, magnesium, zinc and copper in industrial circulating cooling water scale and corrosion products Approved by the Ministry of Chemical Industry of the People's Republic of China on September 16, 1991 and implemented on January 1, 1992
Determination method
HG/T2160-91
HG5--1606 Determination method of sulfate content in industrial circulating cooling water scale and corrosion products HG5-1607 Determination method of carbon dioxide content in industrial circulating cooling water scale and corrosion products 3 Method summary
The cooling water dynamic simulation test method is to use saturated water under normal pressure under given conditions in the laboratory. Steam or hot water heats the heat exchanger, simulating the main parameters of the production site such as flow rate, flow state, water quality, metal material, heat exchange intensity and cooling water inlet and outlet temperature, so as to evaluate the corrosion and scale inhibition performance of the water treatment agent.
4 Test device
Figure 1 Flow chart of the cooling water dynamic simulation test device 1-Supplementary water tank; 2-Water collection tank; 3-Cooling tower: 4-Padding: 5-Water pump: 6-Axial flow fan; 7-Float valve; 8 Inlet flow meter; 9 Sewage flow meter: 10 Temperature measuring element: 11-Connection joint; 12 Heat exchanger; 13-Test tube; 14-Condenser; 15-Electric heating element; 16-Test piece rack 4.1 Heat exchanger system
4.1.1 Heat exchanger
4.1.1.1 Made of corrosion-resistant metal material, the outer wall has a good insulation layer. 4.1.1.2 The heat medium is saturated water vapor under normal pressure. For tests with low heat exchange intensity, hot water can also be used as a reference. 4.1.1.3 The effective length of the heat exchanger is determined by the length of the test tube, which is generally not less than 500mm. 4.1.2 Test tube
4.1.2.1 Size: It is composed of multiple seamless metal tubes with a diameter of 10mm×1mm (other sizes can also be selected as needed), and the length of each tube varies from 150 to 230mm.
4.1.2.2 Material: No. 20 high-quality carbon steel (GB699), and the same metal material as the simulated field equipment can also be selected. 4.1.2.3 The inner wall is required to have no obvious defects, such as pitting, cracks, rust, etc., with positive and negative thread at both ends (other connection methods can also be used), and the outer wall is hard plated.
4.1.3 Connecting joints
4.1.3.1 Size: The outer diameter is not less than 23mm, and the inner hole has positive and negative threads at both ends. 4.1.3.2 Material: Wear-resistant polytetrafluoroethylene. 4.2 Cooling tower system
4.2.1 Collection tank
4.2.1.1 Volume: Generally calculated according to 1/2~1/5 of the hourly water consumption of circulating cooling water. 4.2.1.2 Material: hard plastic.
HG/T2160-91
4.2.1.3 The liquid level should be constant, and can be automatically controlled and supplemented with water. 4.2.2 Cooling tower
4.2.2.1 Size: It should be determined according to the local temperature, humidity and process temperature difference. Usually the diameter is 220mm and the height is 150mm. The height of the packing is about 3/4 of the tower body. The cooling range can reach 10-15℃. 4.2.2.2 Material: hard plastic.
4.2.2.3 Packing: polypropylene ball ring, size 20mm×20mm (or packing with similar cooling effect is also acceptable). 4.2.3 Fan
Fully enclosed axial flow fan, generally with a power of more than 100W. 4.2.4 Water pump
Generally, the head is 4m and the flow rate is 1.32m2/h. 4.3 Instrument system
4.3.1 Temperature measuring element: platinum resistance (BA) or other material temperature measuring resistance, which can automatically print or digitally display (resolution at 0.1℃), and mercury thermometer (division value 0.1℃) can also be used. 4.3.2 Flowmeter: Manual rotor flowmeter can be used, the minimum scale value is less than 2% of the control value, and the manual valve is a needle valve. When installing, it should be easy to disassemble and clean. Automatic adjustment flowmeter can also be used. 4.3.3 Process control and inlet temperature control: During the test, a single-chip microcomputer can be used to control and process data. The inlet water temperature fluctuation is not more than ±0.2℃.
4.4 Pipeline system
4.4.1 Pipeline: Use corrosion-resistant pipes and have good insulation. 4.4.2 Blowdown: Control with flowmeter or other methods. 5 Test water quality
5.1 The test water quality shall be the actual working water. If it cannot be used, water can be prepared according to the main components of the water. 5.2 The prepared water shall be analyzed for the content of its main components. Compared with the raw water, the relative error shall be ±2.5%. 6 Test preparation
6.1 Pretreatment of test tubes
6.1.1 Tube selection: For each test group, three test tubes of different lengths (4.1.2) and corresponding connecting joints (4.1.3) shall be selected. The total length of the connected test tube shall not be greater than the length of the heat exchanger. 6.1.2 Surface treatment: First, use coarse sandpaper [usually with a grain size of 60 (No. 2)] to smooth the pitting and pitting inside the test tube, and then use fine sandpaper [usually with a grain size of 150 (No. 2/0)] to further polish, and then clean the test tube according to Appendix A of GB5776. 6.1.3 Weighing: Carbon steel and low alloy steel are weighed to 1 mg, and corrosion-resistant materials are weighed to 0.5mg. If a large-diameter test tube is used, it can be weighed to 5mg.
6.1.4 Tube installation and measurement: Connect the weighed test tubes of different lengths (4.1.2) to the joints (4.1.3), strictly check whether the joints are leaking, and then measure their effective heat transfer length! (m), accurate to 1mm, see Figure 2. Figure 2 Schematic diagram of effective heat transfer length of test tubes in heat exchanger 1 heat transfer tube; 2-connecting joint: 3-furnace; 4-rubber plug: 5-floor tube 3
Formula for calculating effective heat transfer length:
Wherein: 1 effective heat transfer length of test tube, m; 1-effective length of heat exchanger, m;
12-total length of connecting joints, m.
HG/T2160-91
6.1.5 Record: Record the weight, length, corrosion area, heat transfer area and arrangement position of each test tube in the table A2 of Appendix A respectively.
6.2 Instrument calibration
The flow, temperature, pH value and other measuring instruments should be calibrated in advance. 6.3 Cleaning
Before each test, clean the system with tap water. If necessary, clean it with 5% hydrochloric acid solution (containing 1% hexamethylenetetramine). The pipe material is stainless steel, which can be cleaned with sulfuric acid or nitric acid solution. 6.4 Pre-filming and water treatment agent addition method
If the test tube needs to be pre-filmed, you can wait until the above 6.1~6.3 work is completed, and then directly add the pre-filming agent to the water collection tank at one time. During normal operation, the water treatment agent must be evenly added to the water collection tank. 7 Test steps
7.1 Startup
Every time you start the machine, you must first turn on the water pump, and then pass in steam or hot steam generated by heating. When shutting down, you should first stop the heating (or steam), and then stop the water pump after 30 minutes.
7.2 Determination of thermal resistance of clean pipe
After the steam temperature and cooling water flow have reached the specified value and stabilized for 2~6h, the cooling water inlet and outlet temperatures and steam temperature can be measured 8 times every 15~30min. During the measurement, the flow, inlet temperature and steam temperature should be strictly controlled within the specified value. The abnormal values are discarded by mathematical statistics method, and the arithmetic mean is calculated. The thermal resistance of clean pipe is calculated according to formula (2): nd1x3600
0.86 yuan d, 1
Where:
- Thermal resistance of clean pipe, m2.C/W;
d Inner diameter of test pipe, m;
G Cooling water flow, kg/h;
T Steam temperature,;
Inlet- Cooling water inlet temperature, ;
out——cooling water outlet temperature, ℃;
4186.8-heat capacity of water, J/kg·;
-effective heat exchange length of test tube, m;
3600—value converted from hours to seconds
7.3 Determination of instantaneous fouling thermal resistance
After determining the thermal resistance r of the clean tube, the instantaneous fouling thermal resistance expressed in m2.℃/W can be determined every 2 hours according to the method in 7.2 and calculated by formula 4
(3):
In the formula: G-
0.86 yuan d,1
HG/T2160—91
T-1 floor
-Cooling water flow, kg/h;
-Clean pipe thermal resistance, mC/W
In—Instantaneous inlet temperature of cooling water, C;
-Instantaneous outlet temperature of cooling water, C;
TtIn
-Cooling water inlet temperature when cleaning pipe, ℃;-Cooling water outlet temperature when cleaning pipe, C ; Steam temperature, ℃;
d—inner diameter of test tube, m;
Effective heat transfer length of test tube,
7.4 Determination of concentration multiple, limiting carbonate hardness and evaporation amount T
Under the condition of no sewage discharge, every 2 hours, the chloride determination according to GB6905, the potassium ion determination according to GB10539 and the alkalinity determination according to HG5-1502 are carried out:
a. Total alkalinity (M);
b. Potassium ion (chloride ion can also be used when there is no interference from chemicals). 7.4.1 Calculation of concentration multiple: The concentration multiple (N) in cooling water can be calculated according to formula (4): N
Potassium ion content in circulating cooling water, mg/L; Where: Km
-total potassium ion content in supplementary water, mg/L, K
7.4.2 Calculation of ultimate carbonate hardness: The ultimate carbonate hardness (M) expressed in X10-3mo1/L is calculated according to formula (5): N
-instantaneous concentration multiple of circulating cooling water; Where: N-
-circulating The instantaneous total alkalinity of cooling water, mg/L; M
The instantaneous total alkalinity of make-up water, mg/L,
When the M\ value conforms to formula (5), it is the limiting carbonate hardness M.>02
7.4.3 Calculation of evaporated water volume: The evaporated water volume (Qe) of circulating cooling water expressed in m3/h can be calculated according to Appendix C2 (5)
7.5 Calculation of sewage volume and make-up water volume: The sewage volume (Qb) and make-up water volume (Qm) expressed in m/h can be calculated according to Appendix C3.
7.6 Analysis and determination items
Except potassium ion, chloride and alkalinity, which must be determined, the other chemical analysis and determination items can be determined according to the process requirements. 7.7 Test cycle
The continuous test cycle shall not be less than 15 days. If a fault occurs during the test, the cooling water loop shall not be interrupted more than 2 times. The test time shall not exceed 6h per week
8 Post-test treatment
HG/T2160-91
8.1 After the test, remove the test tube, observe the corrosion and scaling, and determine the chemical composition of the scale, annual scale thermal resistance, scale deposition rate mcm, average scale thickness X, scale layer density p and corrosion rate B, local corrosion depth. 8.2 Press one end of the test tube tightly against the rubber sheet, and add distilled water to the other end with a burette to measure the volume V. After the water is released, dry the test tube in a 105°C forced air oven to constant weight, and its mass is G28.3 Use a stainless steel spoon to gently scrape the dirt inside the tube after drying, and determine the composition of the dirt according to the method HG5-1600~1607. 8.4 The above test tube is then treated according to the method in Appendix B. 8.5 Measure the volume and weigh it according to the method in 8.2, and its volume and mass are V and Gs° respectively. 8.6 Cut the test tube open, observe and record the corrosion morphology in detail, and take photos of typical samples. 9.1 Corrosion 9.1.1 The annual corrosion rate (B) expressed in mm/year is calculated according to formula (6): B
Where: K—-3.65×103;
G—mass reduction of the sample after corrosion, g
—test time, d;
A—corrosion area of the sample, cm2;
D—metal density, g/cm2 (carbon steel 7.85, copper 8.94, brass 8.65, stainless steel 7.92) 9.1.2 The local corrosion depth expressed in mm includes the average depth and the maximum depth. The determination method is shown in Appendix C1.3.9.2 Dirt
9.2.1 The dirt deposition rate (mcm) expressed in mg/cm2. Month is calculated according to formula (7): mcm
Where: Gz is the mass of the test tube after the test, mg,30(G,-G,)
G—the mass of the test tube after removing the dirt, mg: A—the area of the inner surface of the test tube, cm2; T is the test time, d.
9.2.2 The annual dirt thermal resistance (r) expressed in m2.℃/W is determined and calculated according to the following method: (6)
8. Curve method: The instantaneous dirt thermal resistance measured in accordance with 7.3 is discarded by mathematical statistics method, and is used as the vertical coordinate, and the corresponding time (d) is used as the horizontal coordinate. The dirt thermal resistance is drawn by a microcomputer or manually. Multiplying 1.1 is the annual dirt thermal resistance (r): as shown in Figure 3. One time curve. Then take the highest value b of the smooth curve in the figure. Two-point method: Select two points from Figure 3 that are close to the smooth curve and the measured curve. These two points must meet d, (number of days) = 2d, (number of days), and then calculate the annual dirt thermal resistance r as follows: r(d,)
r \2r,(d,)-r,(d,)
Where: r.(d,) instantaneous dirt thermal resistance of operation d, m2, ℃/W; rs(d,)-instantaneous dirt thermal resistance of operation d, m2. C/W6
HG/T2160--91
Figure 3 dirt thermal resistance-time curve
9.2.3 The average scale thickness (x) expressed in mm is calculated according to Appendix C formula (C1). 9.2.4 The scale density (p) expressed in g/cm is calculated according to Appendix C formula (C2). 9
d(days）
9.2.5 The content of chemical components of dirt expressed in percentage shall be determined according to the determination methods specified in HG5-1602, HG5-1603, HG5-1604, HG5-1605, HG5-1606 and HG5-1607. 10 Allowable difference
The allowable difference of two parallel determination results is listed as follows: Table 1 Allowable difference of corrosion rate determination
Corrosion rate range
0.80~0.40
0.41~0.10
Dirt deposition rate range
50.1~15.0
Average scale thickness range
1.00~0.20
Indoor allowable difference
Table 2 Allowable difference of dirt deposition rate determination
Indoor allowable difference||tt ||Table 3 Allowable difference of average scale thickness measurement
Indoor allowable difference
Inter-room allowable difference
ram/year
Inter-room allowable difference
Inter-room allowable difference
Density range
2.00~1.00
HG/T216091
Table 4 Allowable difference of scale density measurement
Indoor allowable difference
Table 5 Standard deviation of annual scale thermal resistance measurement
Annual scale thermal resistance range
0. 7×10~~2. 0×10-
2.1×10~~4.0×10
Main contents of test report
Allowable difference between rooms
11.1 Test tube material, brand, size and treatment method, etc. 11.2 Process parameters: such as concentration multiple, pH value range, water treatment agent content control range, heat transfer area, cooling water inlet and outlet temperature difference, heat exchange intensity, etc.
11.3 Water quality analysis
11.4 Test results
HG/T2160—91
Appendix A
Record table format
(Supplement)
Table A1 Water quality and water treatment Analysis report of water treatment agent
Analysis of water quality
Measurement items
Measurement items
Reversal time
Analysis of water treatment agent
Measurement items
Table A2 Original data record table of dynamic simulation test Steam temperature
Cooling water temperature,
Temperature difference,
Flow rate..kg/h
Concentration multiple
Measurement items
Pre-filming conditions
Test tube length 1(m)
Test tube corrosion area (inner diameter) 4(cm) Test tube original weight G(mg)
Test tube test Weight after test Gz (mg)
Weight gain of dirt G,-G, (mg)
Weight of test tube after descaling G, (mg)
Weight loss of corrosion G,-G (mg)
Corrosion rate B (mm/year)
Volume of test tube after test V, (mL)
Volume of test tube after descaling V (mL)
Volume difference V2-V, (mL)
Heat transfer area F (m)
Scale density p (g/cml)
Average scale thickness X (mm)
Scale deposition rate mcm (mag/cm2, month) B1 steel
HG/T2160-91
Table A3 Original record table of dynamic simulation test
Test tube arrangement position
Appendix B
Test tube surface post-treatment method
(Supplement)
B1.1 Press one end of the test tube that has been scraped off most of the dirt and corrosion products tightly on the rubber plate, and carefully add hydrochloric acid solution [preparation method: hydrochloric acid (GB622) 500mL, hexamethylenetetramine (GB1400) 40g, add water to 1L) to the other end with a dropper until all dirt and corrosion products are removed, but the chrome plating layer on the outside of the test tube must not be damaged, and immediately rinse with tap water until neutral. B1.2 Neutralize with 80g/L sodium hydroxide (GB1266) solution, and then rinse with tap water. B1.3 Soak in anhydrous ethanol (GB678) for 1-2 minutes. B1.4 Take it out and blow it dry immediately. Put it in a desiccator for 1 hour and weigh it. B2 Stainless steel
B2.1 The operation steps are the same as B1, but the hydrochloric acid solution is replaced with nitric acid solution [Preparation method: 100mL of nitric acid (GB626), add water to 1LJ, and soak it at 60℃ for 20min
B3 Aluminum and aluminum alloys
HG/T2160-91
B3.1 The operation steps are the same as B1. But the hydrochloric acid solution is changed to phosphoric acid solution [preparation method: phosphoric acid (GB1282) 50mL, chromic anhydride (CrO2) 20g, add water to 1L), soak at 80~90℃ for 10minB4 Copper and copper alloys
B4.1 The operation steps are the same as B1, but the hydrochloric acid solution is changed to sulfuric acid solution (preparation method: add 100mL sulfuric acid (GB625) to 900mL water and mix well) and soak at room temperature for 1~3min. Appendix C
Test results and calculation of evaporated water, make-up water and sewage volume (supplement)
C1 Calculation of test results
C1.1 Average scale thickness
The average scale thickness (X) expressed in mm is calculated according to formula (C1): (c1)
Where: D-inner diameter of the test tube after descaling, mm; V-volume of the test tube after the test, mL;
V2-volume of the test tube after descaling, mL. C1.2 Scale density
The scale density (p) expressed in g/cm2 is calculated according to formula (c2): G,-G
Where: G is the mass of the test tube after the test, g; - the mass of the test tube after the scale is removed, g
V is the volume of the test tube after the test, mL;
V2 is the volume of the test tube after the scale is removed, mL, C1.3 Determination of local corrosion depth
C1.3.1 Select 5 deepest pits for each test tube. (c2)
C1.3.2 Use a glass pole as a standard plate (uniform thickness, tolerance ±0.01mm, size 80mm×30mm) to measure with a micrometer or a clock meter.
C1.3.3 The average value of the maximum pit depth of the 15 largest pits of the three test tubes is the maximum pit depth value. C2 Determination of evaporated water volume
When the system is not drained, record the height of the replenishment tank liquid level (cm) and time (h). When the replenishment tank liquid level drops to zero, the corresponding time t2 (h) is calculated according to formula (C3) in m\/h for the evaporated water volume (Qe): 11kg/h
Concentration multiple
Measurement items
Pre-filming conditions
Test tube length 1(m)
Test tube corrosion area (inner diameter) 4(cm)Test tube original weight G(mg)
Test tube weight after test Gz(mg)
Fouling weight gain G,-G，（mg）
Test tube weight after defouling G，（mg)
Corrosion weight loss G,-G（mg）
Corrosion rate B（mm/year）
Test tube volume after test V，（mL）
Test tube volume after defouling V(mL)
Volume difference V2-V，（mL)
Heat transfer area F（m）
Scale density p（g/cml）||tt ||Average scale thickness X (mm)
Dirt deposition rate mcm (mag/cm2, month) B1 steel
HG/T2160-91
Table A3 Original record table of dynamic simulation test
Test tube arrangement position
Appendix B
Test tube surface post-treatment method
(Supplement)
B1.1 Press one end of the test tube from which most of the dirt and corrosion products have been scraped off on the rubber plate, and carefully add hydrochloric acid solution [preparation method: hydrochloric acid (GB622) 500mL, hexamethylenetetramine (GB1400) 40mg, add water to 1L] to the other end with a dropper until all the dirt and corrosion products are removed, but the chrome plating layer on the outside of the test tube must not be damaged, and immediately rinse with tap water until it is neutral. B1.2 Neutralize with 80g/L sodium hydroxide (GB1266) solution, then rinse with tap water. B1.3 Soak in anhydrous ethanol (GB678) for 1~2min, B1.4 Take out and blow dry immediately, put in a dryer for 1h and weigh, B2 Stainless steel
B2.1 The operation steps are the same as B1, but the hydrochloric acid solution is replaced with nitric acid solution [Preparation method: 100mL nitric acid (GB626), add water to 1LJ, and soak at 60℃ for 20min
B3 Aluminum and aluminum alloys
HG/T2160-91
B3.1 The operation steps are the same as B1. But the hydrochloric acid solution is changed to phosphoric acid solution [preparation method: phosphoric acid (GB1282) 50mL, chromic anhydride (CrO2) 20g, add water to 1L), soak at 80~90℃ for 10minB4 Copper and copper alloys
B4.1 The operation steps are the same as B1, but the hydrochloric acid solution is changed to sulfuric acid solution (preparation method: add 100mL sulfuric acid (GB625) to 900mL water and mix well) and soak at room temperature for 1~3min. Appendix C
Test results and calculation of evaporated water, make-up water and sewage volume (supplement)
C1 Calculation of test results
C1.1 Average scale thickness
The average scale thickness (X) expressed in mm is calculated according to formula (C1): (c1)
Where: D-inner diameter of the test tube after descaling, mm; V-volume of the test tube after the test, mL;
V2-volume of the test tube after descaling, mL. C1.2 Scale density
The scale density (p) expressed in g/cm2 is calculated according to formula (c2): G,-G
Where: G is the mass of the test tube after the test, g; - the mass of the test tube after the scale is removed, g
V is the volume of the test tube after the test, mL;
V2 is the volume of the test tube after the scale is removed, mL, C1.3 Determination of local corrosion depth
C1.3.1 Select 5 deepest pits for each test tube. (c2)
C1.3.2 Use a glass pole as a standard plate (uniform thickness, tolerance ±0.01mm, size 80mm×30mm) to measure with a micrometer or a clock meter.
C1.3.3 The average value of the maximum pit depth of the 15 largest pits of the three test tubes is the maximum pit depth value. C2 Determination of evaporated water volume
When the system is not drained, record the height of the replenishment tank liquid level (cm) and time (h). When the replenishment tank liquid level drops to zero, the corresponding time t2 (h) is calculated according to formula (C3) in m\/h for the evaporated water volume (Qe): 11kg/h
Concentration multiplewwW.bzxz.Net
Measurement items
Pre-filming conditions
Test tube length 1(m)
Test tube corrosion area (inner diameter) 4(cm)Test tube original weight G(mg)
Test tube weight after test Gz(mg)
Fouling weight gain G,-G，（mg）
Test tube weight after defouling G，（mg)
Corrosion weight loss G,-G（mg）
Corrosion rate B（mm/year）
Test tube volume after test V，（mL）
Test tube volume after defouling V(mL)
Volume difference V2-V，（mL)
Heat transfer area F（m）
Scale density p（g/cml）||tt ||Average scale thickness X (mm)
Dirt deposition rate mcm (mag/cm2, month) B1 steel
HG/T2160-91
Table A3 Original record table of dynamic simulation test
Test tube arrangement position
Appendix B
Test tube surface post-treatment method
(Supplement)
B1.1 Press one end of the test tube from which most of the dirt and corrosion products have been scraped off on the rubber plate, and carefully add hydrochloric acid solution [preparation method: hydrochloric acid (GB622) 500mL, hexamethylenetetramine (GB1400) 40mg, add water to 1L] to the other end with a dropper until all the dirt and corrosion products are removed, but the chrome plating layer on the outside of the test tube must not be damaged, and immediately rinse with tap water until it is neutral. B1.2 Neutralize with 80g/L sodium hydroxide (GB1266) solution, then rinse with tap water. B1.3 Soak in anhydrous ethanol (GB678) for 1~2min, B1.4 Take out and blow dry immediately, put in a dryer for 1h and weigh, B2 Stainless steel
B2.1 The operation steps are the same as B1, but the hydrochloric acid solution is replaced with nitric acid solution [Preparation method: 100mL nitric acid (GB626), add water to 1LJ, and soak at 60℃ for 20min
B3 Aluminum and aluminum alloys
HG/T2160-91
B3.1 The operation steps are the same as B1. But the hydrochloric acid solution is changed to phosphoric acid solution [preparation method: phosphoric acid (GB1282) 50mL, chromic anhydride (CrO2) 20g, add water to 1L), soak at 80~90℃ for 10minB4 Copper and copper alloys
B4.1 The operation steps are the same as B1, but the hydrochloric acid solution is changed to sulfuric acid solution (preparation method: add 100mL sulfuric acid (GB625) to 900mL water and mix well) and soak at room temperature for 1~3min. Appendix C
Test results and calculation of evaporated water, make-up water and sewage volume (supplement)
C1 Calculation of test results
C1.1 Average scale thickness
The average scale thickness (X) expressed in mm is calculated according to formula (C1): (c1)
Where: D-inner diameter of the test tube after descaling, mm; V-volume of the test tube after the test, mL;
V2-volume of the test tube after descaling, mL. C1.2 Scale density
The scale density (p) expressed in g/cm2 is calculated according to formula (c2): G,-G
Where: G is the mass of the test tube after the test, g; - the mass of the test tube after the scale is removed, g
V is the volume of the test tube after the test, mL;
V2 is the volume of the test tube after the scale is removed, mL, C1.3 Determination of local corrosion depth
C1.3.1 Select 5 deepest pits for each test tube. (c2)
C1.3.2 Use a glass pole as a standard plate (uniform thickness, tolerance ±0.01mm, size 80mm×30mm) to measure with a micrometer or a clock meter.
C1.3.3 The average value of the maximum pit depth of the 15 largest pits of the three test tubes is the maximum pit depth value. C2 Determination of evaporated water volume
When the system is not drained, record the height of the replenishment tank liquid level (cm) and time (h). When the replenishment tank liquid level drops to zero, the corresponding time t2 (h) is calculated according to formula (C3) in m\/h for the evaporated water volume (Qe): 11
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