LIGHT OF MY LIFE The new plasma ignition system is safer and more cost effective
Industrial equipment supplier O.E.N. Enterprises has introduced the new Hegwein Microwave Plasma Ignition System manufactured by combustion technology firm Durag Group as part of its portfolio of igniters available to the South African burner market.
O.E.N highlights that firing up large industrial combustion plants with many burners is a complex process requiring equipment such as igniters that require gas or oil to establish the combustion process.
The plasma ignition system generates a bright white plasma at a temperature in excess of 3 500 ºC. Once introduced into the burner, it directly ignites fuels and pulverised solids like coal-sand biomass. It is also able to ignite gaseous and liquid fuels in combustion applications across industries. No additional ignition fuels are required, allowving instantaneous and reliable direct ignition of hard coal burners. This enables higher boiler system availability and improved flexibility of load control, resulting in more efficient energy use.
The plasma is created at the tip of the plasma lance. The plasma ignition system based on the high frequency generator (magnetron) which is built into the lance head, an attached plasma lance including initial ignition spark generator, and a supply unit with a connection line. In principle the plasma is an extended electric arc based on microwave technology.
Advantages of a plasma ignition system include a fast return on investment through the elimination of ignition fuels and the required infrastructure. The system is also safer as it eliminates the ignition burners safety chain as no fuel is used. It also offers a compact design and lower maintenance including less fuel conditioning and less frequent safety audits being required.
Further, the plasma ignition system can be used for the direct ignition of different solid fuels like predried lignite, highly volatile hard coal, coal dust or biomass.
The plasma ignition system is flexible in its applications whereby it can also be used in the chemicals industry and thermal processes systems including oxygen-free thermal reactions.
An alternative ignition product that O.E.N. offers is the Durag D-HG series – a high-energy spark ignition system. It has an integrated temperature control, under- and overvoltage protection, discharge control, short circuit test, light-emitting-diode indication for ignition feedback, ready for operation signal and a built-in fault-finding capability.
The system produces an energy of 5.6 J at a maximum ignition frequency of 20 sparks a second and is fully programmable to suit specific plant requirements. It has varying ignition lance lengths to suit plant specifications, and a retraction unit is also available.
To evaluate the characteristics of the flame produced, the Durag D-LX 201 range of flame monitors provide fail-safe functionality. As the D-LX 201 is burner and flame specific, it measures the electromagnetic radiation in the ultraviolet, visible and infrared region of the flame spectrum and analyses parameters such as intensity, frequency, flicker and the stability of the flame.
These measurement criteria need to be fulfilled in order for the D-LX 201 flame monitor to indicate that there is a flame, as well as provide a valid ‘Flame On’ signal. There is also a RS-485 output available that can be used for diagnostics, or as an output to the appropriate Durag software.
O.E.N. also supplies the WDG-VC oxygen and combustibles analyser, which can be used by all companies that need to monitor boiler efficiency as well as control their stack emissions. The principle of operation is based on a zirconium oxide cell for net oxygen measurement, and dual hot-wire catalytic detectors for both combustibles and methane.