Flare Gas Recovery Units (FGRU)

What Is a Flare Gas Recovery Unit?

A flare gas recovery unit (FGRU) is a system that captures flare gases and redirects them back into production workflows for reuse as fuel gas. This process helps to reduce routine flaring and emissions while saving operators on long-term production costs.  

How Does a Zeeco Flare Gas Recovery Unit Work?

The flare gas recovery process consists of several steps. To begin, gases are redirected from the flare header to the FGRU. Gases pass through a compressor or an ejector and then go to a separator to remove any liquids. The gases then leave the separator, are cooled, and proceed to a knockout drum to remove any condensates before being returned to the plant or facility for reuse. If, at any point, an upset occurs that requires a flaring event, the flare gas recovery process is stopped so that waste gases can be safely destroyed by the facility's flare.

Typical FGRU Sizing:

• • Flowrate ranges: 0.1 to 10MM SCFD (11,100 NM3/hr) — maximum recovery rates can be infinite
  • Pressure ranges: 15 to 1,200 psig (83 barg)

Advantages of Ejectors in FGRU Systems

In certain situations, ejectors may offer distinct advantages over traditional compression technologies. They have no moving parts in the compression zone and can handle a wide range of process conditions. Ejectors may also offer improved reliability, reduced maintenance requirements, and substantial cost savings.

The operation is based on Bernoulli’s principle. In an ejector, the velocity of the motive fluid increases as it passes through the nozzle, creating a low-pressure region within the ejector suction chamber. This action creates a suction, and low-pressure flare gas/vapor is entrained. As the combined high-pressure motive and flare gas or low-pressure gas streams pass through the ejector’s diffuser section, the velocity decreases, and the result is the desired outlet pressure conditions. If high-pressure water or steam is used, a separator is required downstream of the ejector to separate gas from water. If high-pressure gas is used, no downstream separator is needed.

Why Should You Choose Zeeco for Your FGRU Project?

As the industry leader in advanced combustion technologies and environmental solutions, Zeeco has an intricate understanding of flare systems and their ancillary equipment. When you order an FGRU from Zeeco, you're not working with a team that just installs the system but rather a team that ensures your FGRU and ancillary equipment are designed for your specific process conditions so that you get the most out of your new equipment.

Services Offered:

• • Engineered studies: Let us help you determine if an FGRU system is right for your facility. Our engineers will recommend system sizing, compressor technology, and any necessary ancillary equipment. They will develop the cost estimate and evaluate the payback period to help you decide the economic feasibility of an FGRU system.
  • Engineering, design, fabrication, supply, installation, and startup of FGRU packages.
  • Field Support after equipment startup.