Mounting gas ramps
dreizler A 3001 E - 18.12.2015 | A 2021 - 1.15 | EN - 18.05.2015
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32.7 Special gases
32.7.1 Range of application for gas/dual fuel burners with special/aggressive gases
•
Gas burner for operation with special gases only
•
Gas burners for alternating operation with gases from public utilities or special gases
•
Dual fuel burners for alternating operation with special gas or a liquid fuel
•
In larger systems, it is fundamentally possible to mix special gas with other gaseous or liquid fuels for
simultanous use.
32.7.2 Retrofitting of marathon
®
burners for special gases
•
Particularly high-quality valves on the gas side
•
Specific single valves with cast iron valve bodies
•
Viton and teflon seals
•
Impulse lines of non-ferrous, metal-free and particularly corrosion-resistant stainless steel
•
Relevant dimensioning for larger throughput values with lower heating values
•
Depending on the consistency of the special gas, optional mounting of a flame arrester downstream of
the burner mixing unit and valves
•
Valve tightness control
32.7.3 Characteristics of special gases, e.g. bio, process or landfill gas
•
Fluctuating heating values with different chemical compositions. Methane content should be a min. of
40%
•
Highly reactive components, e.g. hydrogen H
2
, carbon monoxide CO and oxygen O
2
in various and
changing concentrations. Max. O
2
concentration in combustion gas without flame arrestor < 0.1 VOL%
O
2
•
Gaseous aggressive molecules like hydrogen sulfide H
2
S and ammonia NH
3
. Max. H
2
S concentration
should not surpass 200ppm.
•
Low gas pressures at correspondingly high volume flows. Min. gas pressure for special gas
20mbar up to 500kW, for higher values on request.
•
Moisture in steam or liquid form. Moisture as condensate in the components must be avoided.
NOTICE:
Careful pre-processing of the special gas before it is supplied to the burner is required.
The special gas should be supplied to the burner at high pressure (20-500mbar dep.on burner size).
The special gas must be supplied to the burner gas ramp dry.
Any construction-side condensate inside the burner gas ramp must be eliminated.
NOTICE:
Due to insufficient options to influence adjustable parameters, no warranty is provided for gas
ramp components which come into contact with special gas.
Particular attention must be given to the valve assemblies during maintenance.
Shorter maintenance intervals are required.
Due to the various compositions of the special gases, commissioning will be more complex.
