Gas Generators – Part 4 – FID Gas Stations

In my final installment of gas generators, I will discuss combination gas generators called FID Gas Stations.  For those of you not familiar with gas chromatographs or their detectors, FID refers to a Flame Ionization Detector.  Because hydrogen and air are used to produce the FID flame, those are the gases produced by these generators.  The hydrogen acts as the fuel gas, and the air supplies the oxidizer (oxygen).  The GC/FID provides the ignition source.

If you are wondering how these generators operate, I suggest reviewing two previous blog posts I wrote on gas generators, Gas Generators – Part 1 – Hydrogen Generators and Gas Generators – Part 3 – Zero Air Generators.  The hydrogen section of the FID Gas Station operates similarly to a PEM hydrogen generator.  Water molecules are split into oxygen and hydrogen and the oxygen is vented.  The zero-air generator section operates by pushing compressed air through a prefilter (to remove oil, water and larger particulates), then through a catalyst module (which oxidizes hydrocarbons into carbon dioxide and water vapor), and finally through final particulate filter (to remove very small particulates (0.5 micron)). 

Restek sells two models, the FID-1000 (Restek part # 20177) and the FID-2500 (Restek custom part # 580073).  You can find the Parker Installation, Operation and Maintenance manual here. TI_FID1000J_Gas_Stations.pdf (parker.com)

There are several important specifications which I will mention at this time.  

1. These units are bulky, so the recommended installation is on a bench top.  Mounting onto a wall is not recommended, nor is suspending these units from a ceiling.
2. These units should be installed in a climate-controlled environment which has a temperature range between 60°F and 100°F.
3. The water source should be deionized water with a resistivity of at least 5 Mega-Ohm/cm.  Restek part # 22000 (Parker HydroGen Mate DI Water System) can provide water which meets specifications.  
4. A source of clean, dry compressed air with a pressure between 40 and 125psi is required.

FID-1000

The FID-1000 is capable of 90cc/min of 99.9995% hydrogen with a maximum output pressure of 60psi.  It is capable of 1000cc/min zero-grade air with a maximum output pressure of 125psi.  Zero-grade air purity is defined as containing less than <0.1ppm methane (hydrocarbon) output.  

FID-2500

The FID-2500 is capable of 250cc/min of 99.9995% hydrogen with a maximum output pressure of 60psi.  It is capable of 2500cc/min of zero-grade air with a maximum output pressure of 125psi.  As with the FID-1000, zero-grade air purity for the FID-2500 is defined as containing less than <0.1ppm methane (hydrocarbon) output.

Please review page 21 of the manual for System Specifications and Replacement Parts.  Maintenance for both models include the following:

1. Refilling the water reservoir once a week with deionized water.  Consider using Restek part # 22000 (Parker model # 72-230) as the source of the deionized water.  The annual maintenance kit for the Parker HydroGen Mate is Restek 22001 (Parker 72236).  This kit contains one prefilter, two resin cartridges, and one final filter.
2. Replacing the resin bed cartridge approximately every 6-months, or when the color changes 75%.  The Restek part # for the resin bed cartridge is 24914 (Parker # B02-0323).
3. Changing the desiccant cartridge when the orange-colored beads become clear.  The Restek part # for the desiccant cartridge is 21671 (Parker # 1647727)
4. Replacement of filters annually.  Restek kit 24915 (Parker MKFID1000) contains the resin bed cartridge listed in #2 (above), the desiccant cartridge listed in #3 (above), and a prefilter and a final filter.
5. Replacement of the catalyst tower every 2-years.  The Parker part number for the FID-1000 catalyst tower is either B02-0298 or B02-0437 (depending on the unit’s serial number), and B02-0361 for the FID-2500.

Just a few more comments before I wrap up this post, and my series on gas generators.

1. The hydrogen produced from the FID Gas Stations is not recommended for use as the GC carrier gas.  You will want to select a PEMPD hydrogen generator instead.  
2. Restek may be able to provide, as a custom part number, any product in this post in which only a Parker part number is listed (such as with the catalyst towers).  Please contact your Restek sales representative or distributor to obtain a quote.
3. If either the hydrogen or zero-grade air section of this generator needs serviced, you may not have a source of that gas available until the unit is repaired.  As a result, you should always have a back-up plan, as you would with any critical gas supply, whether you keep a few gas cylinders available onsite, or have a separate generator for each gas.  Some customers prefer owning two separate gas generators for this reason. 
4. As with all gas generators, if you need assistance with selection, please have the following information available.

1. 1. Gas required.
   2. Purity required.
   3. Flow rate required.
   4. Output pressure required.

Thank you for reading my series on gas generators.  Let us know if you have any questions.