Construction material combustion thermal value test method

This standard refers to ISO 1716-1973 "Determination of the thermal value of building materials"

1 The subject content and applicable range

This standard specifies the definition of total combustion value of the building materials, the determination method and the definition of combustion thermal value, and method.

This standard is suitable for the determination of the combustion value of building materials.

2 Terms and Symbols

The heat released when a material is completely burned. Not only is the quality of the material, the state of the combustion product is related, but also under constant pressure in constant compassion at constant compassion at the time of burning. The thermal value confirmed in this standard is the constant capacity measured in the oxygen bomb.

a. Total combustion thermal value (hereinafter referred to as total heating value)

The material of the unit quality is completely combustion, and the water vapor in its combustion product (including water steam generated during water vapor in the material and the hydrogen in the composition of hydrogen) is condensed into liquid state. Heat, is defined as the total combustion value of the material.

b. Combustion value (hereinafter referred to as hot value)

The material of the unit mass is completely burned, and the water in the combustion product ( The water vapor generated when the hydrogen combustion generated in the water vapor and material composition produced in the material is still present in the form of heat in the form of a gaseous form, and is defined as the combustion value of the material. It is equivalent to a difference in vaporization of water vapor generated after the total thermal value subtracts the material after combustion, and the difference in vaporization latent heat released when the oxygen is condensed as water. c. Quantum thermometric heat capacity

The heat required for temperature rise at a temperature increase of 1 ° C under test conditions is defined as The heat capacity of heat gaps. The value is obtained by calibrating the test under the same test conditions by quantitative thermal reference substance benzoic acid. The heat system includes all portions of the temperature in the water and measurement during the thermometer.

D. Quantating reference substance

For a reference substance for calibration thermometric heat capacity. This standard refers to an equal heat standard benzoic acid.

2.2 Symbols

QZR total thermal value, KJ / Kg; qjr thermal value, KJ / Kg;

as a reference substance And according to the instrument instruction manual, the measured calorimeter heat capacity, KJ / ° C;

TI moderate thermometer in the water temperature, ° C;

TM mode medium temperature thermometer internal cylinder is highest water temperature, ° C; heat exchange between cube thermometer inner cylinder and constant temperature outdoor Positive value, ° C;

c Additional heat correction value, Kj;

M sample quality, kg

;

N prime; from the beginning to temperature increase equal to 0.6 (TM-Ti) this moment Time, S; V prime; the average temperature change rate of the initial stage, ° C / S;

V prime; the average temperature at the end of the test period Change rate, ° C / s;

MA attached mass, kg;

MF ignition wire mass, kg;

HON samples generate HNO3 generation heat, Kj;

Q Samples After burning, the vaporization heat released in water condensed in the oxygen bomb, KJ / KG.

3 Test environment conditions

a. The laboratory should be located in a single room And do not assume the measurement of other test items while simultaneously in the same room.

b. The laboratory room temperature should be maintained in the range of 15 to 35 ° C, and the room temperature varies in time at each time measurement must not exceed 1 ° C.

C. There should be no strong air convection within the laboratory, and there should be a strong heat source and fan.The doors and windows should be avoided during the test.

D. The laboratory should avoid direct sunlight, otherwise the amount of thermometer should be placed in a position that is not directly exposed by the sun.

4 Instrumentation equipment

4.1 aerobic bullets thermometer (see Figure 1

1-inner cylinder; 2-stirrer; 3-outer cylinder; 4-stirring motor; 5-outer cylinder thermometer

6-inner cylinder cover; 7-electrode; 8-temperature measuring device; 9-aerobic bomb; 10-thermal heat pillar

Fig. 2 oxygen bullet

1-intake pipe; 2-intake valve; 3-electrode; 4-exhaust valve;

5-Burning baffle; 6-crucible; 7-坩 坩;

b. Summer-of-calorimeter : The surface of the inside and outside polished, with a full set of accessories.

c. Quantitative heat gauge outer cylinder (water jacket): complete accessories. D. Constant mixer: complete accessories.

e. Temperature Measurement Device: Used to measure the water temperature of the thermometer in the thermometer, its accuracy is 0.002 ° C.

F. Ignition device: The voltage does not exceed 20V.

a. Analysis of Balance: Maximum Weigh 200g, index value: 0.1mg.

b. Industrial Balance: Maximum Weigh 5KG, index value: 25mg.

4.3 Affiliated Equipment

a. Oxygen Cylinder. b. Oxygen deponger and oxygen conduit.

C. Platinum crucible, nickel-chromium or silica crucible and other heat resistant corrosion resistant and oxidation resistant materials, and can place a sample of the sample. D. Ordinary mercury thermometer: The test range is 0 ~ 50 ° C, the index value is 0.2 ~ 0.5 ° C.

5 reagents

a. Oxygen: contentu003e 99.0%, and should not contain flammable components, so electrolytic oxygen is not allowed.

b. Benzoic acid: benzoic acid identified and indicated by metering agencies. 3 to 4 h were placed in an oven at 40 to 50 ° C and then cooled to a benzoic acid sheet of 0.9 to 1.1 g of a benzoic acid sheet on the tablet machine, and it was split into a dryer.

c. Sodium hydroxide standard solution, C (NaOH) 0.1 mol / L.

D. Phenolphthalein indicator, 0.1%.

e. Ignition: platinum, copper, nickel-chromium wire or other known hot value of 0.1 mm diameter, cutting it into a small section of length 80 to 100 mm , Placed in the analysis of the balance (accurate to 0.1 mg) and calculate the corresponding hot value.

f. Whip: Take the hot value before use. The method is as follows: Take a 1g rubber paper, after analyzing the balance (accurate to 0.1 mg), tighten it with the hand, put it in the crucible, and then according to this standard, sections 7.1.2 ~ 7.1.7 Step Determine its thermal value. Take the average of two results as calibration.

6 sample preparation.

6.1 Sampling

a. Use the hand-made steel saw along the surface of the material The vertical direction saws several long short ports, and saw materials should be perpendicular to the surface of the saw blade as much as possible to ensure the representation of the sample sample. Collect the powder under the saw, fully and mix it, then remove 10 g of a sample of about 2 ~ 3 times.

b. Other methods that can be made of representative samples can also be employed. 6.2 State adjustment

Put the prepared sample in the temperature of 23 PLUSMN; 2 ° C, relative humidity is 50 plusmn; 5% The state in the environment is adjusted after 20h, and then stores the ready-to-depression dryer (or other closed container).

7 Total thermal values

7.1 Measurement step

7.1.1 Precisely weighs the status-regulated building materials sample 1.0 ~1.2g (accurate to 0.1 mg). With the exactly weighed to 0.1 mg and the wipped paper wrapped in the wippers, the wrapped sample should be paid to the sample, so that the sample is closely contacted with the wiping paper to ensure complete combustion of the sample. . Put the package in the crucible and use the hand pressure. The amount of flammable ingredients containing flammable components in the dosage test sample, generally 0.5 to 1.5g, the general principle is that the inner cylinders caused by the plasma and the wiring paper in the oxygen bomb, 1.5 ~ 3.0 ° C.

7.1.2 takes a known quality and thermal value of the ignition, and the both ends are connected to both the oxygen bomb, pay attention to keep good contact, and then The crucible of the sample is placed on the crucible bracket. Adjusting the ignition filament is good contact with the sample, and notice that the ignition filament is touched with the crucible to avoid short-circuiting, burn the crucible bracket, and should also pay attention to preventing the two electrodes from being short-circuited between the two electrodes and the crucible.

Add 10ml distilled water to the oxygen, gently put the blanket that has been loaded with the sample and ignition filaments into the bomb, carefully tighten the bomb cover, pay attention to avoid the crucible and The position of the ignition is disengaged from the vibration change. After the oxygen conduit, first driven by a slow oxygen stream, turn off the exhaust valve, and then reach the oxygen in the oxygen until the bomb pressure is 2.5 MPa. For refractory materials, the bomb pressure should be charged to 3.0 to 3.2 MPa.

7.1.4 Adding a quantity of distilled water in the inner tube, the amount of distilled water is placed in the top surface of the oxygen-lever render after the oxygen bullet (excluding the protruding oxygen valve and electrode) 10 to 20 mm under the surface of the water. The amount of inner cylinders during each test must be consistent with the amount of inner tube when the calibration heat capacity (within 1 g). Determination of water volume measurement method, accurately weighed to 1G at industrial balance.

Adjusts the water temperature of the inner cylinder, which is 0.7 to 1.0 ° C lower than the outer cylinder. The water temperature of the outer tube should be as close as possible to room temperature, and the difference is not exceeded 1 ° C.

7.1.5 Put the inner cylinder of the water into the amount of the heat gap (the water jacket), and then put the oxygen-filled oxygen bomb, and install it. In the gear electrode, the ignition electrode of the oxygen bomb is connected to the ignition circuit, cover the upper cylinder, and insert the temperature measuring device into the inner tube through the small hole on the cover.

7.1.6 Turn on the stirrer, the stirring speed is the same as the calibration heat capacity. After 3 minutes, start timing and read the refore of the water temperature. One time per minute, two consecutive read 5 min, this stage is the initial stage of the thermal value test. The aerobic amount of the aerobic amount with microcomputer starts the temperature measurement program according to its operating instructions. After the initial end, immediately close the ignition circuitThe line ignition, the thermal value test immediately entered the main period, recorded the inner cubular water temperature Ti, and then once every 30s record.

Note that the inner cylinder temperature, such as the temperature rise in 30s, indicating that the ignition is successful, and the test can continue, otherwise the test should be stopped immediately.

When the inner tube water temperature reaches the highest value Tm, the test automatically enters the end, and the inner tube water temperature gradually begins to decline. At this time, the water temperature changes should be recorded once a minute and record 5 min. After 5 min, close the stirrer and record the temperature of the temperature at this time.

7.1.7 Remove the oxygen bomb, turn on the vent valve, slowly discharge the combustion exhaust gas and remove the bomb cover, carefully observe the inside of the tube and the 坩. If there is any signs of the non-complete signs of the sample, the test should be disadvantaged. Find out unburned ignites, weighted (accurate to 0.1 mg), calculating the heat of the burning ignition in the oxygen bomb.

With distilled water rinse, the exhaust valves, inside and outside and the burning residue are used. All wash solution was collected in a beaker and titrated the resulting nitric acid with 0.1 mol / L sodium hydroxide standard solution.

The production of nitric acid consumed by 1 ml of 0.1 mol / L of sodium hydroxide standard solution was 5.987J.

7.2 Results Calculation

a. Ordinary aerobic bullet thermometer

Test The total thermal value is calculated by the following formula: M

E TTC C

Q KJ Kg Mi

? +?

() (/) ???????????? (1)

formula: c (n-n prime;) V prime; -N prime;

c mahoa + mfhof + HON

b. Thermometer with microcomputer

According to the requirements of the instrument's instruction manual, the computer inputs the heat capacity, sample quality, and additional heat, etc. according to the requirements, and the computer is based on the data and test processes.You can automatically perform the calculation of temperature correction and total hot value QZR, and automatically display the calculation results.

7.3 Number of samples and repetition test difference The thermal value test has a total of three average samples. The difference between each two parallel experiments shall not be greater than

167 kJ / kg, otherwise the entire test should be done.

7.4 Measurement results expression

The repetitive test difference of 3 thermal value test results of a material of 3 average samples of a material When the provisions of 7.3, the arithmetic mean of this 3 test results is used as the total calorific value of the material.

8 thermal value calculation

8.1 Materials are combustion after burning in the oxygen bomb Calculation of water of water

8.1.1 Determination of hydrogen content

According to 6.1, a representative powder chart is made State mediation in 6.2 regulations, and then use microaly analysis to determine the content F of hydrogen in the material composition.

The measurement of the hydrogen content was carried out twice, and the allowable error of the two measurements should not exceed 0.15%.

8.1.2 Calculation of Surgent Substation

Q (KJ / KG) 218.13f ???????? ???? (2)

8.2 thermal value calculation

QJR (kJ / kg) QZR-Q ????? ??????? (3)

9 Test report

Test The report should include the following:

a. Standard for the test;

b. Material name, trademark and manufacturer;

c. Material appearance, component and density;

d. Test results:

Total hot Value (KJ / KG)

Test 1

Test 2

Test 3

Average value

condensed water

e. Test phenomenon;

f. Entrust the test unit;

g. Test unit;

H. Test personnel and test dates.

Additional description:

This standard is provided by the Ministry of Public Security of the People's Republic of China.

This standard is attributed by the National Fire Standardization Technical Committee.

This standard was drafted by the Ministry of Public Security Sichuan Fire Science Research Institute and the Ministry of Construction.

This standard mainly drafted He Yumei, Ding Min, Sun Yuhu, Martao.