A Super Sonic Solution - John Zink Company

a report by
John Zink, a division of Koch Chemical Technology Group Ltd
The KMI flare tip is a hybrid of the highly
successful John Zink ® Hydra and Kaldair ®
Indair ® technology. The concept of multiple Indair
tips being located in an array is not new; however,
John Zink have developed the concept into a
single-point tip with multiple Indair nozzles. This
not only provides the multi-arm advantages of the
Hydra by increasing the flare gas surface area
exposed to the air, but also employs the infinite
turndown features of the variable slot Indair.
Each KMI arm terminates with a variable slot
Indair nozzle. The Indair nozzle utilises the
‘Coanda effect’ to entrain and mix air into the
hydrocarbon gas stream. High-pressure gas is
ejected radially from the annular slot at the base of
the Indair tulip. Instead of continuing horizontally,
the gas adheres to the Coanda profile and is
diverted through 90 degrees, forming a thin film
over the tulip surface and entraining up to 20 times
its own volume of air in the process.
Advantages of the KMI
Smokeless Operation
Due to its unique pre-mixed turbulent flame, high
air entrainment rate and thin film combustion
technique, the KMI flare tip provides smokeless
flaring of most hydrocarbon gas stream.
Low Radiation
The KMI flare tip produces a highly aerated
turbulent diffusion flame that radiates far less heat
than any other flare tip of its type
Purge Rates/burn-back
Unlike other sonic flares, the KMI does not suffer
from burn-back and requires a fraction of the purge
gas needed for conventional sonic flare tips.
Flame Length
The flame length produced by a single Indair is less
than half that produced by a conventional API-type
pipe flare. The KMI flame is even shorter.
Flame Stability
Technology & Services
Figure 1: The Coanda Principle
A Super Sonic Solution
Figure 2: KMI Systems Offshore West Africa
The KMI flare produces a stiff flame with a high
directional stability that is not easily distorted by crosswinds.
The unique geometry and stiff directional flame
allow the KMI to be mounted at an angle without
detrimental effect to tip operation or life. In offshore
applications the flame can be angled away from the
platform or floating production storage and offload
(FPSO) vessel, reducing deck radiation.
BUSINESS BRIEFING: EXPLORATION & PRODUCTION: THE OIL & GAS REVIEW 2005 – ISSUE 2
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Liquid Handling
Technology & Services
Figure 3: KMI Demonstrates Clean Stable
Directional Flame
Figure 4: 2 Million Kg/hr KMI tip supplied to Kazakhstan
The KMI flare is capable of burning 25% by weight
of liquid carry-over without any fall-out or smoke
production whatsoever. This feature means that, in
many cases, the flare may be operated without a
liquid knockout drum in the HP flare line.
High-pressure Operation
Since the KMI flare operates at elevated pressure
when burning HP gas (rather than near atmospheric
pressure as with a conventional flare), significant
savings in header size and knock-out vessel size may
be made.
Efficient Air Entrainment and
Mixing
Multi-point designs improve the efficiency by
splitting the flow between smaller, separated
cylinders of hydrocarbon gases, allowing efficient air
entrainment into the flame. The unique KMI flare
tip, based on the Coanda effect, forms a thin film of
hydrocarbon that entrains and pre-mixes air prior to
combustion. The KMI flare, in most cases, produces
combustion efficiencies in excess of 99.9%.
Tip life
The small Indair tulips used in the KMI are of an
investment cast, highly robust single part construction
that, combined with the multi-nozzle design, provides
extended operational life compared with other flare
tips on the market.
Maintenance
As the KMI tulips are very small they are easily manhandled.
Therefore, in the event that any tulips require
changing, it can be done without the use of a crane. In
addition, the replacement of an investment cast small
tulip is not expensive whereas the manufacturing cost
of a large tulip is relatively high.
Flexibility
Turndown flexibility can be enhanced further by
varying the spring rates on the individual nozzles
such that the flare tip can act as a staged system in
itself. Thus, the tip can be set up to bring nozzles
online in turn, such that at low flows only one or
two nozzles will have their slots open while all the
others are closed. As the pressure and flow increase
then slots can open in sequence until at full flow all
slots are fully open ■
BUSINESS BRIEFING: EXPLORATION & PRODUCTION: THE OIL & GAS REVIEW 2005 – ISSUE 2