Atmospheric distillation units ELOU AVT-6 (ADU)
KASUS and partners develop the full or partial modernisation projects based on technical efficiency and wishes of customers, manufacture and supply of equipment, provide the supervision and start up service of atmospheric distillation units.
Scope of supply and service for ADU Units
Atmospheric and atmospheric-vacuum crude oil distillation units of types ELOU AVT - 6, AVT - 5, AT and others are head refining units in all refineries.
In these units, ELOU AVT-6 with a design capacity 6 MMTA in particular, there are the whole or the main part of the refinery crude oil processed.
So, reliable crude units operation has a primary importance for the efficient operations of the whole refinery.
In 1976 – 1989 there were twelve ELOU AVT-6 units built:
· 7 units in Russian Federation: Moscow (1), Ufa (2), Grozny (7),
Nizhnekamsk (8) , Saratov (10), Syzran (11), Novokuibyshevsk (12)
· 2 units in Azerbaijan: Baku refinery Azerneftyanajag (3) and refinery Azerneftyag (4)
· 2 units in Ukraine: OAO Lisichansknefteorgsyntez (5, 6)
· 1 unit in Turkmenistan: refinery Saidi (9)
The construction of these units was at that time the progressive solution and signified substantial step ahead compared to the previously used technology.
Meanwhile, time is elapsing and minimum life of these units is 20 years though maximum reaches 30 years. Obviously, that many of these many units are considerably depreciated morally or physically and many equipment items should be replaced.
So, the modernisation of the existing crude units and ELOU AVT-6 in particular is the obvious strategic way to secure the reliable operation of the refineries.
However even the selection of the optimum modernisation scenario for each individual refinery is not an easy task.
Based on our experience we believe that there are three min possible options of the crude units modernisation:
· The complete modernisation with the replacement of all critical or outdated equipment items for new ones.
· Replacement of the old equipment items for the same type of new ones, if they are still available on the equipment market.
In many cases this is already impossible because the manufacturers of this old equipment are already out of this business.
· Combination of the options 1 and 2 and realisation of the staged modernisation with gradual equipment replacement.
KASUS has a suggest realisation of the similar projects according to all three scenarios as above. So, today, we would like to make you acquainted
With some approaches which we developed with our partners to address the issues of modernisation of crude units. As an example we use the ELOU AVT-6 units.
Furnaces ( P1/1, P1/2, P1/3)
Coils and fittings : replacement using the same type of materials but with the different designation
Insulation : modernisation using the new design and materials
Burners: replacement of the old burners for the new ones with automatic flame dampening
Sooths blowers: new advanced types (the old ones are not manufactured anymore)
Transfer and vapour lines: matching the ASTM and DIN specs
Chimney fans: the use of modern much more compact models with:
· lower dimensions and weight
· lower engine power at the same capacity (740 rpm vs. 590rpm withold ones)
· higher efficiency– 76.5% vs. 72% with old ones
Cost of the new model is lower.
There are few options ofmodernisation:
· Supply of the new old model multistage pumps with double mechanical seals
· Revamp of the old pumps with the installation of double mechanical seals
These options are recommended during the partial replacement of one or two pumps at each definiteprocess position.
Advantages: There are no needs to replace thepiping and operating conditions.
Disadvantages: There might be theproblems withthe spare parts in the future.
· Supply of the new 1-stage or 2-stagepumps.
This option is recommended when allpumps at the definite process position shouldbereplaced.
Advantages: Lower operating cost due to lowerutilities consumption, easy maintenance procedures due to use of cartridge seals andsimple designof the pump, the possibility of individual materialsselection for the pump housing, working wheels and shaft for the pumps operating in different processpositions and medias.
Significantly lower cost of thesepumps and their increased efficiency considerably exceeds the expenses for new foundations and piping of the new pumps.
Atmospheric and vacuum columns
· Vacuum columns: Vacuum Tubes Individual packing selection fordifferent sections of the column
· Atmospheric columns: Development of the new internals / trays and selection of thematerials for trays, fixtures, beams and
other internals for the different sections of the columns
Heat recovery units: Economizer
Development of the new, simple design of economizerswith the assembling at the manufacturing plant
Advantages: High reliability due to use of thesteel core instead of the cast iron fin elements and theabsence of all flanges.
The cost of new economizers is lower.
Electrical equipment might be modernised by partial replacement of some equipment items, first of all, electrical motors and other items with increased wear (transformers, relays, contactors, insulators and so on).
It is a very critical part of the revamp, because the majority of the old-model spare parts are not manufactured anymore.
Controlling system is one of the most important areas of the unit modernisation, which requires immediate improvements. Controlling system modernisation might be realised according to different scenarios:
· Replacement of pneumatic instruments for new models (controllers, converters and so on).
This option is recommended for short term solution of existing problems and non-sufficient funding.
· The conversion of the whole system to modern electronic control system.
This option is recommended for the comprehensive solution of the unit control problems, because the use of pneumatic control system at large modern crude units cannot be justified economically or technically.
· Significant increase of the unit reliability and reduction of start-up/shut-down time
· Reduction of operating/maintenance cost as the of the whole unit, so a control system
· Capability of increasing of unit capacity
· Many other advantages
The examples above clearly demonstrate that modernisation of ELOU AVT-6 and other crude units is necessary requirement for the refineries in their long term programs of operating cost reduction and improvement of reliability and safety of the units operation, increase throughput and hence the reduction of the production cost what leads to the higher refinery profitability.
KASUS provides the comprehensive modernisation projects, taking the singular responsibility for the design, procurement and delivery and assembling, supervision and start-up of the equipment according to the following scheme
Questionnaire and detailed information about scope of equipment for ADU unit ELOU AVT-6 on request.