How to calculate the gas consumption of a piece of equipment

The calculation of the gas consumption of the equipment shall be based on the specific gas type and equipment characteristics. The following are the detailed calculation methods and precautions:

calculation of 1. compressed air consumption

formula:
q=273.15⋅(1+0.00367T)V⋅P

• Q compressed air consumption (unit: m & sup3;/min)
• V air compressor displacement (unit: m & sup3;/min)
• P compressed air pressure (unit: MPa)
• T: Compressed air temperature (unit: ℃)

example:
an air compressor displacement V = 10m & sup3;/min, pressure P = 0.7MPa, temperature T = 25 ℃, substituted into the formula:
q≈273.15×(1+0.00367×25)10×0.7 ≈9.32m³/min

calculation of 2. LPG gas consumption

formula:
q=V⋅ρ

• Q: LPG gas consumption (unit: m & sup3;)
• V: LPG Volume (Unit: L)
• ρ density of LPG (Unit: kg/m & sup3;)

example:
50L LPG tank, density & rho;= 0.55 kg/m & sup3;, then:
q=50×0.55=27.5m³

calculation of Gas Consumption for 3. Natural Gas

formula:
Q = gas calorific value heat load & sdot;860 & sdot; thermal efficiency

• Q: Gas consumption of natural gas (unit: m & sup3;/h)
• heat load: Equipment power (in kW)
• thermal efficiency: Equipment thermal efficiency (percentage)
• calorific value of gas calorific value of natural gas (unit: kcal/m & sup3;, generally 8500kcal/m & sup3;)

example:
24kW heating furnace, thermal efficiency 89%, then:
q=850024×860×0.89 ≈2.16m³/h

4. general estimation method

1. flow meter method:
   directly read the data of flow meter or gas meter and calculate the gas consumption (unit: m & sup3;).
   Formula:
   gas consumption = post-meter reading & minus; pre-meter reading

2. equipment Nameplate Method:
   refer to the rated power, efficiency and other parameters on the equipment specification or nameplate, and estimate the gas consumption in combination with the operation time.

5. considerations

1. equipment characteristics:
   • consider whether the equipment is running with load, start-stop frequency and other factors.
   • Gas leakage will significantly increase the amount of gas, the need to regularly check the tightness.
2. Environmental conditions:
   • the temperature increase will cause the gas to expand, and the pressure change needs to correct the calculated value.
   • Air density decreases in high altitude areas and gas consumption estimates need to be adjusted.
3. measurement error:
   • the error of the civil gas meter may reach 3%, and the industrial flowmeter needs to be calibrated regularly.
4. Safety Redundancy:
   • in industrial scenarios, it is recommended to select the type according to 1.2 & minus;1.5 times of the calculated value to avoid insufficient gas supply.

6. practical application scenarios

by selecting the calculation method reasonably and considering the actual working conditions, the gas consumption of the equipment can be accurately estimated, which provides the basis for the selection, energy saving and safety management.