We provide quiet, reliable “Zero-Grade” Air Generators for Gas Analyzers

 For proper, noise-free operation, several types of standard CO₂ quality testing equipment (e.g. Total Hydrocarbon [THC], Oxidative-Total Sulfur (TSC) + Process GC/FID Analyzers) require a moderate flow (typically 300 cc/min @ 50 - 80 psig) of “THC-free” pure air (THC <0.1 ppm v/v as methane). This low THC purity specification is typically referred to as “zero-grade” air. This grade of air can be supplied by a high pressure zero-grade air cylinder or a lesser-grade air cylinder + zero-air generator (ZAG) unit or by a combined air compressor-ZAG unit.

Use of high pressure air cylinders often presents several problems for many CO₂ manufacturing, bottling plant or brewery customers. For example, local supplies of zero-grade air cylinders may not be available in their region. In some cases, when cylinders are available, they must be stored outdoors at a great distance from the CO₂ analyzer area. Several cylinder safety issues must be addressed and strictly enforced, such as the proper handling of high pressure cylinders, transportation, secure storage, proper connective procedures, periodic leak testing and adequate venting. An additional operational cost factor involves the daily cylinder rental fee charged by the gas supplier.

To avoid the issues associated with high pressure air cylinders, many laboratory and industrial customers are now using our compact Air Compressor-ZAG (AC-ZAG) units. The ZAG units contain an electrically heated catalyst element which “flamelessly burns” (oxidizes) all methane* and other oxidizable vapors in the incoming air into CO₂.

*Normal, clean air contains about 2 ppm v/v of methane. These ZAG units should not be operated in environments that contain a high organic solvent vapor level exceeding about 6 ppm v/v as methane.

Our rugged zero-air generator units are shipped fully assembled, tested and “ready-to-run”. They produce “THC-free” air at a 0 - 70 psig settable delivery pressure and a maximum zero-grade air flow rate of about 1L/min. An automatic drain control mounted on the air reservoir eliminates the need for performing daily labor-intensive water condensate draining. This auto drain-control feature makes our compressor-ZAG system essentially “maintenance-free”. The capacity of the large air reservoir leads to very low “duty cycles” for the compressor unit. For example, when interfaced with several gas analyzer loads, the compressor typically runs for only about 10 sec then sits quietly for about 15 - 20 minutes.

The air compressor we employ is a highly reliable industry standard (our p/n GAST 200x-120) with a 1/4 HP @ 120 VAC/60 Hz motor. “Step-down” transformers are available for use with other VAC power sources. The compressor is mounted on a 2 gal reservoir and is equipped with automatic min-max (80 - 125 psig) pressure control, wired 9’ power cord, 22.5” flex connective tubing + brass quick connect port fittings. A “user-settable” automatic drain control assembly (p/n 6Z948, Speedaire - with a 1/4” compression outlet port) is installed onto the reservoir drain. The compressor assembly is coupled onto an anodized frame and interfaced to a Parker-Balston 75-83SA Catalytic Zero Air Generator module (our p/n ZAG-P75-83NA [120 VAC/60Hz/0.5A]). A pressure regulator with a 0 - 80 psig delivery range is installed between the compressor and ZAG. Typically this regulator is shipped pre-set @ 50 psig which is recommended for THC analyzer applications. The standard ZAG outlet is a 1/16” compression fitting.

Recommended spare parts for this AC-ZAG system include a replacement intake air filter (p/n B344A), fiber filter element (p/n 050-05-BX) and ss in-line 0.5 micron filter cartridge (p/n SS-2F-05). These low cost filters are replaced very infrequently (approx. 1X/yr or as experience warrants).

Another key reason for our AC-ZAG equipment recommendations involves the high level of after-sales customer support that is offered. GAST Manufacturing and Parker-Balston have support offices in Europe and many other world locations that will assist you in any field support issue. ALI also provides our customers with liasson service and spare parts to help ensure reliable system performance.

Shown below is our turn-key Air Compressor - ZAG System. Please contact us if you have any questions or require a quotation.