Ground Flares

Ground flare systems are often chosen due to their efficiency in handling multiple operating cases with large variations in flow rates, 100% smokeless capabilities, the ability to completely conceal flames, and operating noise is much lower than elevated flares. A low- pressure first stage may be assisted with steam or air for smokeless, but the second stage and beyond would not need assist air or steam since the pressure of the waste gas exiting the burner tips induces efficient air to flare smokelessly.

Ground flares can be “totally enclosed” or “multi-point”. Both of these technologies use a fence to conceal flames and protect surrounding areas from radiation and noise. All of the ground flare equipment, including pilots and pilot thermocouples, are located at grade. Thermocouples can be retractable for convenient and safe maintenance.

There are many considerations in designing a ground flare system. EnviroPro is knowledgeable and experienced in ground flare applications. Contact us to discuss your project.

Ground flares
Ground flares
Enclosed Ground Flares
  • Multipoint Ground Flares
  • Totally Enclosed Ground Flares

Multipoint Ground Flares

Multipoint ground flares are 100% smokeless flare systems that break up the gas loading into separate stages and burners. As pressure in the flare header increases and decreases, a PLC opens and closes valves to bring stages online or take them off. A proper velocity is maintained to sufficiently pull air into the combustion zone and burn 100% smokeless. If the first stage is open to the process, assist steam or air would be needed for smokeless operation.

The flare field is surrounded by a fence that hides much of the flame from view and protects the surrounding area from radiation. All staging valves and controls are located outside the fence and are accessible for maintenance even when the flare is online.

Typical applications where multipoint ground flares are used include:

  • Ethylene plants
  • Poly ethylene and propylene plants
  • Methanol plants

Multipoint ground flares are used wherever the flare gas flow is relatively high, 100% smokeless operation is required, higher DRE is desired and noise and light pollution must be kept to a minimum.

Ground flares

Totally Enclosed Ground Flares

Totally enclosed ground flares have stages like multipoint ground flares and use flare gas pressure to operate 100% smokelessly. Instead of a fence, waste gasses are burned inside a refractory lined combustor. Totally enclosed ground flares burn vapors with a high destruction efficiency and emit no noise or light pollution. Because combustion occurs inside an enclosure, there’s a practical limit to the amount of vapors that can be flared. Common applications for totally enclosed ground flares include marine vapor combustors, truck loading terminals, and tank vent combustors.

Under certain circumstances, low pressure vapors can be flared smokelessly in a totally enclosed ground flare without the use of assist air or steam. Talk to the EnviroPro flare experts to see if your application fits.

Totally enclosed ground flares have also been used to flare vapors that are considered the process cases or day-to-day flaring of a plant with the emergency release of vapors piped to an elevated or multipoint ground flare.

enclosed ground flares