Gas consumption standard for chemical enterprises

The gas consumption standards of chemical enterprises vary greatly due to processes, equipment and products, and need to be determined through testing or estimation in conjunction with specific needs. The following is a detailed analysis:

determination method of gas consumption standard for 1.

1. Test method (applicable to existing plant)
   • steps:
     • close the air valve of the air tank and the system, and close the air release valve after the pressure is reduced to 0.48MPa.
     • Record the time (seconds) required for the gas tank to pump to 0.69MPa, and substitute the formula to calculate the actual gas volume:
       C = V(P₂-P₁) × 60 / T × Pa
       (C: compressor displacement, m & sup3;/min;V: volume of gas storage tank and pipeline, m & sup3;;P/P: final/initial pressure, MPa;T: time, s;Pa: atmospheric pressure, 0.1MPa)
   • judgment standard:
     • if the calculation result is close to the rated gas volume of the compressor, it indicates that the system load is too high and the gas supply needs to be increased.
2. Estimation method (for new plant or expansion)
   • formula:
     V total = V equipment + V post-treatment + V leakage + V reserve
     (V total: total gas consumption; V equipment: gas consumption of existing equipment; V post-treatment: gas consumption of post-treatment equipment; V leakage: leakage; V reserve: safety reserve)
   • safety margin: It is recommended to enlarge 20%-30% to meet future demand.

2. Key Factors Affecting Gas Consumption

1. equipment characteristics
   • type and scale large equipment (such as reaction kettle, distillation tower) gas consumption is 5-10 times that of small equipment.
   • Gas quality requirements: Oil-free compressed air equipment consumes 15%-20% more energy than conventional equipment.
2. Production process
   • continuous process: Continuous gas supply is required, and the fluctuation of gas consumption is small.
   • intermittent process: For batch reactions, the peak gas consumption can reach 2-3 times the average value.
3. operation management
   • leakage rate: When the leakage of the system exceeds 5%, plugging shall be given priority.
   • Equipment maintenance: The efficiency of old equipment decreases and gas consumption increases by 10%-15%.

3. gas consumption optimization strategy

1. technology upgrade
   • efficient equipment: Using variable frequency air compressor, energy saving 20%-35%.
   • waste heat recovery: Using compression heat to heat process water, the recovery efficiency is 60%-70%.
2. Energy Management
   • intelligent monitoring: Install dew point meter and flow meter to analyze gas consumption mode in real time.
   • Staggering gas: Store compressed air during low electricity price periods to reduce operating costs.
3. System Maintenance
   • regular inspection: Air tightness test shall be carried out every year, and the leakage shall be less than 5% of the total gas consumption.
   • Device Update: Eliminate old equipment for more than 10 years, and increase the efficiency of new equipment by 30%-50%.
4. process optimization
   • process reengineering: Simplify the gas delivery path, reduce elbow resistance, and reduce pressure loss by 25%-40%.
   • Exhaust gas recirculation: Reuse low-quality waste gas after purification, reducing fresh gas demand by 10%-15%.

4. industry reference data

• gas consumption of typical chemical equipment:
  • 500L reactor: 0.8-1.2m & sup3;/min (oil-free compressed air).
  • Distillation column: 2.5-4.0m & sup3;/min (pressure ≥ 0.7MPa).
  • Filling line: 1.5-3.0m & sup3;/min (intermittent gas, need to be buffered by gas storage tank).
• Energy-saving transformation case:
  • A chemical plant has upgraded screw air compressor + waste heat recovery, saving 12% of annual gas and reducing electricity expenditure by 800000 yuan.

Conclusion: Chemical companies need to determine gas consumption standards through a combination of testing and estimation, and continuously optimize equipment, management and processes to reduce energy consumption. It is recommended to formulate a personalized gas use plan based on the actual production data of the enterprise.