1. Subject content and scope of application
This standard specifies the determination and calculation method of ozone concentration, output and power consumption of ozone generator.
It is suitable for the determination of ozone generator with electricity as energy.

2 terms
Specific energy consumption
The electric energy consumed by the equipment to produce the finished product of unit weight.

Measurement and calculation method of ozone concentration, output and power consumption of ozone generator Ozone concentration 1.3
3.1.1 summary of method principle: ozone (O3) is a strong oxidant, which can react with potassium iodide (KI) aqueous solution to free iodine. After sampling and acidifying the solution, titrate the free iodine with 0.1000mol/l sodium thiosulfate (Na2S2O3) standard solution and starch solution as indicator, and calculate the ozone amount according to the consumption of sodium thiosulfate standard solution. The reaction formula is as follows
O3+2KI+H2O——O2+I2+2KOH（1）
I2+2Na2S2O3——2NaI+Na2S4O6（2）
3.1.2 reagents
3.1.2.1 potassium iodide (KI) solution (20%): dissolve 200g potassium iodide (analytical purity) in 1000ml boiled and cooled distilled water, store it in a brown bottle in the refrigerator, and store it for at least one day. This solution contains 0.20g potassium iodide in 1.00mL.
3.1.2.2 (1+5) sulfuric acid (H2SO4) solution: take concentrated sulfuric acid (p=1.84; analytical purity) to dissolve in 5 times of volume distilled water.
3.1.2.3 C (Na2S2O3 · 5H2O) = 0.1000mol/l sodium thiosulfate standard solution; use analytical balance to accurately weigh 24.817g sodium thiosulfate (Na2S2O3 · 5H2O; analytical pure) and dissolve it in 1000ml volumetric flask with newly boiled and cooled distilled water. Or 25g sodium thiosulfate (Na2S2O3 · 5H2O; analytical pure) is dissolved in 1000ml newly boiled and cooled distilled water, and the concentration of sodium thiosulfate in this solution is about 0.1mol/l. Add 0.2g sodium carbonate (na2s0o3) or 5ml trichloromethane (CHCl3); calibrate, adjust the concentration to 0.1000mol/l and store it in a brown bottle. If the storage time is too long, it needs to be calibrated again before use (see Appendix A for calibration method).
3.1.2.4 starch solution: weigh 1g of soluble starch, mix it with cold water to form suspension slurry, add about 80ml of boiling water, stir while adding it, dilute to 100ml; put it for a few minutes after boiling for overnight, take the supernatant for use, and add 1.25 * * * salicylic acid or 0.4g zinc chloride if it needs to be preserved for a long time.
3.1.3 test instruments, equipment and requirements
3.1.3.1 triangle washing bottle (absorption bottle) 500ml.
3.1.3.2 if the burette is 50ml, precision burette should be used.
3.1.3.3 the capacity of wet gas flowmeter is 5L.
3.1.3.4 each measuring cylinder is 20ml and 500ml.
3.1.3.5 graduated suction pipe (suction pipe) 10ml.
3.1.3.6 capacity bottle 1000ml.
3.1.3.7 polyethylene or PVC hose for the transport of ozone containing gases. Rubber pipes are not allowed.
3.1.4 Test procedure and method: take 20ml of potassium iodide solution (3.1.2.1), pour it into 500ml absorption bottle, add 350ml of distilled water, take samples at the outlet of ozonation gas after the ozonator is stable, and then measure the gas by means of wet gas flowmeter (3.1.3.3) after absorption of ozone by absorption bottle (3.1.3.1), and the gas passing volume is 2000ml (time control) After about 4min, 5ml (1+5) sulfuric acid solution (3.1.2.2) was added immediately after sampling was stopped (to reduce the pH value to below 2.0) and shake well, and then stand for 5min. Titrate with 0.1000mol/l standard deep solution of sodium thiosulfate (3.1.2.3), add a few drops (about 1ml) of starch solution (3.1.2.4) when the solution is light yellow, and continue to carefully and quickly remove the color of titration. Record the amount of sodium thiosulfate standard solution.
3.1.5 calculation of ozone concentration
Co3=ANa×B×2400/V0（mg/L） （3）
Where: CO3 - ozone concentration, mg/l;
Ana - the amount of sodium thiosulfate standard solution, ml;
B -- concentration of standard solution of sodium thiosulfate, mol/l;
V0 - sampling volume of ozonation gas, ml;
When the ozone concentration is more than or equal to 3mg/l, the precision of the test results is within ± 1%.
3.2 ozone production
3.2.1 principle summary: the product of ozone concentration value and total gas quantity entering ozone generator is output.
3.2.2 equipment, instruments and requirements
3.2.2.1 pressure gauge level 1.5
3.2.2.2 industrial level of gas rotor flowmeter
3.2.3 correction calculation of gas flow: the temperature and pressure of the measured gas when the flowmeter is used are often different from the timing of the meter graduation mark. Therefore, the flow display value of reading in use is often not the true reflection of the gas flowing through the flowmeter, and must be corrected. The formula is as follows:
Qn= (pstn/pnts) 1 / 2 · QS (m3/h or l/h) (4)
Where: QN - actual gas flow rate, m3/h or l/h in standard state;
QS - the display flow rate of gas in the instrument, m3/h or l/h under the measurement (test) state;
PS -- pressure of gas under the condition of measurement (test), PA;
TN - absolute temperature of instrument calibration, (273.15+20) K;
TS - the temperature K of the gas in the measurement (test) state;
PN - absolute pressure (a standard atmospheric pressure of 1.01325 × 105Pa) when the instrument is in calibration state.
3.2.4 calculation of ozone production
Do3 = CO3 · QN (g or Mg) (5)
Where do3 - ozone production, g or mg.
3.3 power consumption
3.3.1 principle summary: the ratio of measured power consumption of ozone generator to unit ozone output is power consumption.
3.3.2 equipment, instruments and requirements.
3.3.2.1 voltmeter (voltmeter) class 0.5.
3.3.2.2 ammeter (ammeter) class 0.5.
3.3.2.3 power meter (watt meter) class 0.5.
3.3.2.4 static high voltage meter level 1.5.
3.3.2.5 watt hour meter level 2.0.
3.3.3 power consumption calculation: the power consumption is calculated by the measured value of power meter (watt meter) (3.3.2.3) or the ratio of accumulated value recorded in unit time of watt meter (3.3.2.5) to ozone production in unit time, and the formula is as follows:
P = w / do3 (w · H / g · O3 or kW · H / kg · O3) (6) or
P = ah / do3 (w · H / g · O3 or kW · H / kg · O3) (7)
Where p is the unit power consumption of ozone, w · h/g.o3 or kW · h/kg · O3;
W - electric power, w or kW;
Ah - cumulative value in unit time of watt hour meter, kW · H.
Appendix a calibration of sodium thiosulfate standard solution (Supplement)
This appendix lists two calibration methods for sodium thiosulfate standard solution, which are used equally in the calibration of sodium thiosulfate standard solution.
A1 method 1
A1.1 reagents
A1.1.1 potassium iodide (KI), analytical purity.
A1.1.2 C (1/6k2cr2o7) =0.1000mol/l * * * potassium standard solution: accurately weigh it with analytical balance and dry it for 2 hours at 105-110oc, and cool it in a silica gel dryer for more than 30min, and shake it in a 1000ml volumetric flask.
A1.2 test instruments, equipment and requirements
A1.2.1 250ml iodine measuring bottle;
A1.2.2 weigh liquid pipe 10.00ml;
A1.3 method and steps: weigh 1g of potassium iodide (a1.1.1) into 250ml iodine measuring bottle (a1.2.1), add 100ml of distilled water, transfer 10.00ml, 0.1000mol/l * * * potassium standard solution (a1.1.2) with pipette (a1.2.2), add 5ml (1+5) sulfuric acid solution (3.1.2.2), and put it in for 5min. Titrate with the standard solution of sodium thiosulfate to be calibrated (3.1.2.3). After the solution becomes pale yellow, add about 1ml starch solution (3.1.2.4), continue titration until the blue is eliminated, and record the dosage. The concentration of sodium thiosulfate standard solution is:
N1=N2V/V1（mol/L）（A1）
Where N1 - sodium thiosulfate standard solution concentration, mol/l;
N2 - standard solution concentration of ** * * * potassium, 0.1000mol/l;
V1 - consumption of sodium thiosulfate solution, ml;
V2: take the volume of standard solution of * * * * potassium, ml;
A2 method 2
A2.1 reagents
A2.1.1 potassium iodate (KIO3).
A2.1.2 acetic acid (CH3COOH).
A2.2 Methods and steps: use the analytical balance to weigh 0.15g of potassium iodate (a2.1.1) for 1 hour accurately, and cool in a silica gel dryer for more than 30min, put them into 250ml iodine measuring bottle (a1.2.1), add 100ml distilled water to each bottle to dissolve potassium iodate, add 3G potassium iodide (a1.1.1) and 10ml of acetic acid (a2.1.2) respectively, shake well, stand in the dark for 5min, and use After the solution becomes pale yellow, add about 1ml starch solution (3.1.2.4), continue titration until the blue is eliminated, and record the dosage. The concentration of standard solution of sodium thiosulfate is:
B=W/ V×214.00/6000=W/ V×0.03567 （mol/L） （A2）
Where B is the concentration of standard solution of sodium thiosulfate, mol/l;
W -- weight of potassium iodate, G;
V -- consumption of standard solution of sodium thiosulfate, ml.
The difference between the results of two parallel samples shall not be greater than 2%.
Appendix B mass measured (Reference)
This appendix is a description of the quality of the measurement.
B1 chemical analysis
B1.1 general rules: the general rules of this standard for chemical analysis (terms, terms, selection and washing of glass instruments, etc.) refer to the relevant contents of gb5750 Standard Inspection Law for drinking water (Part I General and 1 General rules).
B1.2 solution quality: except for the influence of reagent quality, other factors affecting the quality of solution, avoidance and prevention methods shall be implemented according to relevant regulations.

Note: please refer to the relevant contents of "water and wastewater monitoring and analysis" (Third Edition) "preparation of six chemical reagents and test solutions (V) quality of test solution".
B1.3 solution representation
B1.3.1 concentration: in this standard, concentration refers to the concentration of quantity (molar concentration) as follows:
C（B）=a mol/L
Where C - concentration symbol;
(B) - basic unit of substance;
A - concentration value;
Mol/l - unit.
B1.3.2 (a+b) solution: solution "a" mixed in a certain volume proportion represents the volume of solute, and "B" represents the volume of solvent.
B1.3.3 solution (a%): it is customary to weigh the percentage concentration of weight. In chemical analysis, it is often used to refer to the ratio of mass (weight) of solute a to the volume of solution (m/v), which is an inaccurate representation. The standard lists "a%" in brackets as a mark of customary use. The method of expression used in this standard is: 1.00mL of the solution contains a gram of a substance, and a refers to the quantity of mass (weight) of a substance.
B2 instruments and instruments
B2.1 balance, electrical instrument, flow and pressure instrument shall be calibrated and corrected regularly.
B2.2 the verification and correction of electrical instruments shall be carried out according to relevant national regulations and regulations. The verification and correction shall be conducted in the authorized verification and calibration unit of the state, and the verification and correction of the instruments have been verified and corrected shall be provided with certificates.
B2.3 flow and pressure instruments shall be verified and corrected according to relevant national regulations and regulations.
B2.4 the verification of glass gauge capacity shall be carried out according to relevant national regulations and regulations. Please refer to the water and wastewater monitoring and analysis law (Third Edition) "capacity verification of five measuring instruments".
B3 method of representation of measurement results and data processing
B3.1 the method and data processing of measurement results shall refer to the relevant contents of gb5750 "part I General principles, 3 representation methods and data processing of water quality inspection results".

Additional instructions
The standard quota Institute of Ministry of construction of this standard is proposed.
This standard is under the centralized management of North China Design Institute of municipal engineering, the standard and technical unit of urban water treatment equipment and equipment of Ministry of construction of the people's Republic of China.
This standard is drafted by the Department of Environmental Engineering (chief editor), Tsinghua University equipment and instrument factory, Beijing Yuyuantan environmental protection equipment factory and Jiangsu Taixing environmental protection equipment factory.
The main drafter of this standard: liulijin.
The standard is entrusted to the Department of environmental engineering of Tsinghua University for interpretation.