The DID Gas Chromatograph has been designed to make use of the variations in electrical conductibility found in highly ionised gas. The ionisation is created by a single high frequency discharge within the detector (HF Plasma), causing a high energy photon emission (24.5 eV). This emission is capable of ionising all the gases within the cell with the exception of the Helium.
One of the biggest advantage of our DID Gas Chromatograph is that a photo-ionised discharge is achieved without any radioactive emissions and without the need to apply excessive voltage being applied to the cell.
Another important characteristic of the DID Gas Chromatograph is that the detector operates using just one gas. This one gas is used as the carrier, the flushing gas and/or the purging gas. This gas can also serve to purge and clean all the valves.
The housing does not require flushing gas: no contamination of the gas circuit is possible before detection as the input connection is located directly on the cell of the DID Gas Chromatograph detector.
The power setting of the high frequency oscillator allows for the adjustment of the detector sensitivity, which can reach 0.1 ppb (parts per billion).
The detection limit and any background noise and directly related to the quality of the carrier gas, so the use of ultra purity (UHP) Helium as the carrier gas is highly recommended.
Some Global References
|Company||Type of analyser||Model||Measurement|
|Linde (China)||Helium||DID||H2, Ne, O2+Ar, N2, CH4|
|Air Liquide (France)||Oxygen||DID||N2|
|Linde Worms (Germany)||Argon||DID / Orthosmart||H2, O2, N2, CO, CO2, CH4, NMHC|
|Linde (Germany)||Nitrogen||DID+FID||H2, O2, Ar, CH4, CO, CO2, NMHC|
|Air Liquide (France)||Krypton||DID||H2, O2+Ar, N2, Xe|
Type of configurations
DID Gas Chromatograph - 500
This new line 500 has been designed for stand alone operation. Easy configuration and quick start-up make this new system ideal for process gas analysis.
In addition to its user-friendly interface (touch screen display), the new line 500 has its own chromatographic software that allows the concentration of each impurity to be displayed directly. Moreover, the new line 500 can be remotely controlled through Ethernet or Internet.
|Accuracy||1 % of the reading scale|
|Drift||1 % over 24 hours|
|Temperature drift||1 % per degree|
|Operating temperature||± 20°C without wide variations of temperature|
|Sampling gas||He, N2 , H2, O2, Ar, CO2 , Kr, Xe|
|Sample gas connection||1/8’’ Swagelok OR 1/8’’ VCR.|
|Sample flow rate||Approximately 3 to 5 l/h|
|Sample pressure||< 100 mBar|
|Carrier gas connection||1/8’’ Swagelok OR 1/8’’ VCR.|
|Carrier gas pressure||7 bar|
|Carrier gas flow rate||4 l/h|
|Recommended quality||minimum 6.0|
|Power supply||220 Vac, 50-60 Hz|
|Power consumption||420 VA|
|4-20 mA output||Eight confi gurable outputs
depending on the application.
|RJ-45 connection||Computerised system maintenance|
(SPST 2 amperes / 250 Vac)
|1 Analyser Failure Alarm contact
1 Alarm High contact
1 Alarm High High contact
|CH4||< 1 ppb||< 1 ppb||< 1 ppb||< 1 ppb||< 1 ppb|
|CO||< 1 ppb||< 1 ppb||< 1 ppb||< 1 ppb||< 1 ppb|
|H2||< 1 ppb||/||< 1 ppb||< 1 ppb||< 1 ppb|
|N2||< 1 ppb||< 1 ppb||/||< 1 ppb||< 1 ppb|
|O2 + Ar||/||< 1 ppb||< 1 ppb||/||< 1 ppb|
|Ar||/||/||/||< 1 ppb||/|
|Ne||/||/||/||/||< 100 ppb|
|Kr||/||/||/||/||< 1 ppb|
|CO2||/||/||/||/||< 1 ppb|
|Xe||/||/||/||/||< 5 ppb|