Calorimeter calorimeter principle and common sense

1. What is the meaning of fuel heating?

A: The calorific value of fuel refers to the heat released when the unit weight of fuel is completely burned. The unit is J/g or MJ/kg.

2. What are the requirements for the calorimetric chamber?

Answer: (1) The heat chamber should be used as a dedicated chamber for measuring calorific value, and no other test work can be performed indoors;

(2) Curtains should be provided indoors to avoid direct sunlight;

(3) It is advisable that the change of temperature does not exceed 1°C at each measurement; the difference between room temperature in winter and summer should not exceed 15 to 30°C. Therefore, conditions should be prepared air-conditioning equipment;

(4) When measuring calorific value, strong ventilation and heat radiation should be avoided indoors. In short, in order to reduce the influence of environmental conditions on the calorific value measurement results, the calorific value measurement chamber should be kept as relatively constant as possible at room temperature. The calorific value must not be measured when the room temperature is not constant.

3. What should you watch out for during oxygen bomb oxygenation?

A: (1) First, check whether the oxygen pressure gauge is in good condition, sensitive, and whether the indicated pressure is correct and whether the operation is safe.

(2) When oxygenating oxygen bombs, the pressure must be slowly raised until the specified pressure is maintained for 0.5-1 min.

(3) Do not touch grease when using oxygen.

(4) Oxygen bomb oxygenation should be carried out according to the specified pressure. The oxygenation pressure must not be too low or too high.

4. After one calorific value measurement, it was found that there were unburnt coal samples in the combustion flank. What are the reasons for the test analysis?

A: The possible causes are:

(1) Insufficient oxygenation pressure or oxygen bomb leakage;

(2) The coal quality is too bad and the volatile matter is too low;

(3) The oxygenation rate is too fast or the position of the combustion pan is not correct, so that the sample is splashed out;

(4) The ignition wire is buried deeper into pulverized coal;

(5) The sample contains too much water or too much pulverized coal.

5. What is the reason why the combustion vessel is not lit?

Answer: The reason is:

(1) Poor contact of ignition switch or adjustment knob;

(2) Ignition wire and electrode fall off;

(3) Short circuit caused by contact of the ignition wire with the combustion vessel or the combustion vessel with another electrode;

(4) poor contact between the ignition wire and the sample;

(5) The oxygenation pressure is low;

(6) The sample has too high moisture content, too low volatility, and the sample particles are too large;

(7) Oxygen leaks.