no ta for ba! fool!, page-4

New analyst report http://www.lnglimited.com.au/IRM/Company/ShowPage.aspx?CPID=1385&PageName=Patersons Results and Recent Achievements 29 September 2009

Plus cut & paste from website for the lazy

The Optimised Single Mixed Refrigerant (OSMR)

Process Advantages
The process described above has the following benefits over traditional LNG plants:
• Simplicity in design, construction and operation. Uses far less equipment and
packaged items than conventional propane-mixed refrigerant or cascade processes.
Uses the simplest of all liquefaction processes being single mixed refrigerant (SMR)
and the simplest of all of the various versions of the SMR process. For instance, the
main compressor comprises a single stage unit (no inter-stage cooler or scrubber, no
gearbox, no helper motor) and the single mixed refrigerant stream comprises only 4
components. The cold box has only 3 main stream passes and 2 minor passes plus a
2 phase internal MR separator.
• High fuel efficiency and low emissions. Uses the most efficient proven gas turbine
mechanical drive available which is 20% more fuel efficient than much larger
industrial turbines used in traditional modern large-scale LNG plants. This alone
results in a process which is more fuel efficient than conventional large-scale
propane-mixed refrigerant processes.
• Integrated systems. Combined heat and power (CHP) technology uses waste heat
from the gas turbines plus an auxiliary boiler fired with low Btu BOG to provide all
electrical power (via steam turbine generator) and heating requirements for the plant.
Part of this “free” energy is used to drive standard packaged ammonia refrigeration
compressors which provides additional “free” refrigeration for:
o gas turbine inlet air cooling (improves plant capacity by ~15%)
o process cooling (reduces size of dehydration plant and balances regeneration
gas with GT fuel gas)
o cooling the CSG and MR in the cold box (improves plant capacity by 20% and
efficiency by another 20%).
• Low cost and efficient liquefaction system. The mixed refrigerant system is
designed to provide a close match on the cooling curves thereby maximising
refrigeration efficiency. The additional ammonia refrigeration improves the heat
transfer at the warm end of the main heat exchanger by increasing the LMTD which
reduces the cold box size.
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This also provides a cool MR suction temperature to the compressor which
significantly improves the compressor capacity. The high refrigeration plant
efficiency, use of CHP to meet all plant heat and electrical power requirements and
the use of dry low emissions combustors in the gas turbines, results in very low
overall plant emissions. In addition, the plant is designed to avoid flaring during
normal operation and during ship loading.
• Efficient BOG recovery. The BOG system recovers flash gas and BOG gas
generated from the LNG tank and from ships during loading. This gas is compressed
in 2 stage centrifugal BOG compressors to only ~6 bara where is it re-liquefied in
the cold box to recover methane as liquid. The methane returns to the LNG tank and
the flash gas which is concentrated in nitrogen is used for boiler fuel. This is a cost
effective and energy efficient way of dealing with BOG and rejecting nitrogen from
the system, and at the same time minimise or eliminate flaring during ship loading.
• Lower plant capital and operating/maintenance costs. Less equipment items and
modular packages results in reduced civil, mechanical, piping, electrical and
instrumentation works and fast construction schedule; all of which contribute to
reduced costs. This results in simple operations requiring less operating and
maintenance staff. The majority of maintenance costs are dedicated to the gas turbine
drives so the use of aero-derivative gas turbines substantially reduces maintenance
costs.
• High reliability, availability and maintainability (RAM). The high plant RAM,
compared to alternative processes, is principally due to the two separate, independent
and parallel liquefaction circuits utilizing highly reliable aero-derivative gas turbine
drives, combined with using minimal equipment items. Although the process is
highly integrated, the failure of any item will not cause a plant shutdown. For
instance, the plant will continue to operate if the complete ammonia plant (which has
6 compressors in parallel) shuts down or if the OTSG and steam turbine generator
shuts down. Full plant power is provided by a reliable steam turbine system and is
backed-up by the mains utility grid. The installation of spare rotating equipment
(other than the main gas turbine/compressors and steam turbine generator), careful
selection of key rotating equipment and holding of critical spare parts items in-stock
also contribute to high RAM. For instance, the main gas turbine aero-derivative
engines can be quickly changed over as is the case with all aero-derivative gas
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turbines. Low maintenance reliable centrifugal equipment (for MR and BOG
compressors; amine and boiler pumps) have been selected as opposed to less reliable
reciprocating machines.
• Selection of membrane tank. A membrane tank consists of a thin stainless steel
primary container (membrane) together with thermal insulation and a concrete tank
which jointly form an integrated composite structure, to provide the liquid
containment and transfer hydrostatic and other loadings to the outer concrete tank.
The concrete tank is slip-formed resulting in a very fast and economical method of
construction. The quantity of low temperature alloy steel and associated welding
required for the inner tank is less than 10% of that required for a traditional nickel
steel tank. The risks associated with membrane tanks are similar to that of full
containment tanks. The overwhelming benefit of a membrane tank is the capital cost
which is around half that of full containment tanks and a schedule saving of around 8
months.
• Fast construction schedule. The use of modular shop fabricated packages and
selection of standard equipment items where possible, allows an accelerated
schedule. Long lead equipment items such as the MR compressor, gas turbine, cold
box and BOG compressor have deliveries of under 18 months, although this will
need to be confirmed at the time of order.
In summary, the above advantages result in the following project cost (Dec-08) and
efficiency which surpass all other LNG processes including those of a much larger scale:
• EPC Capital cost of US$500m for 1.5mtpa which equates to USD330/tpa including
the disproportionately large LNG storage capacity versus plant production rate.
• Plant energy consumption which consumes ~7.0% of feedgas in energy terms
including all utility systems.