How to calculate the gas consumption of the factory

The calculation of plant gas consumption needs to take into account equipment operating requirements, system losses and future expansion planning, as follows:

1. Basic data of statistical equipment

• gas consumption of single equipment: Refer to the equipment nameplate or technical manual and record the rated gas consumption of each gas equipment (unit: cubic meters/minute or liters/second).
• Frequency of use of equipment: Record the daily operation time of the equipment (e. g. 8 hours/day) and the working cycle (e. g. continuous operation or intermittent operation).

2. Calculate the daily air consumption of a single equipment.

• Formula daily air consumption of single equipment = rated air consumption × daily operation time.
• Example: If the rated gas consumption of a certain equipment is 0.5 cubic meters/minute and it runs for 8 hours per day, its daily gas consumption is 0.5 × 8 × 60=240 cubic meters.

3. Summarize the total gas consumption of equipment in the whole plant

• add the daily air consumption of all equipment to obtain the total daily air consumption of the plant.
• Formula: Total daily air consumption of the plant = & Sigma;(daily air consumption of a single unit).

4. Consider system losses and safety margins

• pipeline leakage: For leakage of compressed air system pipelines due to loose joints, pipeline damage, etc., a margin of 10%-30% of the total air consumption is usually reserved.
• Equipment aging: The decline in equipment performance may lead to an increase in gas consumption. It is recommended to reserve a margin of 5%-10%.
• Future Expansion: If the factory plans to add new equipment or expand production, additional gas shall be reserved according to the expected increase (e. g. 20%).

5. Determine the basis for air compressor selection

• compressor displacement: It needs to be greater than the total gas consumption of the factory (including system loss and safety margin).
• Pressure demand: Select the compressor according to the maximum working pressure required by the equipment (e. g. 7bar) and ensure that the pipeline pressure loss (usually 0.5-1bar) is taken into account.

Example calculation
suppose a factory has 3 devices:

• equipment A:0.5m & sup3;/min, running 8 hours/day
• equipment B:0.3m & sup3;/min, running 6 hours/day
• equipment C:0.2m & sup3;/min, running 24 hours/day

daily air consumption of a single unit:

• a:0.5 × 8 × 60=240m³
• B :0.3 × 6 × 60=108m³
• c:0.2 × 24 × 60=288m³

total daily gas consumption of the plant: 240+108+288=636m & sup3;
including loss and margin: 636 × 1.3 (system loss) × 1.1 (safety margin) & asynmp; 912m & sup3;

conclusion: The factory needs to select an air compressor with a displacement of at least 912m & sup3;/day, and ensure that its pressure output meets the equipment requirements. By regularly detecting pipeline leaks and optimizing equipment operating time, gas efficiency can be further improved.