EA041077B1 - OPTIMIZING FIRE PROTECTION FOR THE OFFSHORE PLATFORM - Google Patents

Description

The present invention relates to a method for optimizing fire protection for an offshore platform of an oil and gas installation and to an offshore platform with optimized fire protection. In exemplary embodiments of the invention, the offshore platform is a production platform for an oil and gas installation.

Offshore platforms must be designed with fire in mind, and this is especially true for oil and gas installations due to the presence of combustible hydrocarbons. Although steps are taken to minimize the risk of fire, the risk of fire and the damage it can cause must still be considered. Fire protection is usually installed to ensure the safety of personnel; to prevent the spread of fire to other parts of the oil and gas installation, such as pipelines and wells; and to prevent damage to the structure of the platform itself. Existing oil and gas platforms use both passive fire protection (PSF) and active fire protection (APS) as well as fire alarm systems to alert the operator of a fire.

The PPP attempts to contain fires or slow the spread of fires through the use of fire screens, fire dampers, and intumescent fire retardants, among other things. The fire protection zone is inactive until a fire occurs, although regular inspection and/or maintenance may be required, for example, to ensure that fire walls or seals are intact and not damaged. In the event of a fire, the FPV responds to the occurrence of a fire by providing fire resistance, for example, by slowing down the transfer of heat between compartments, preventing flame movement, restricting airflow, and so on. There are no systems that start the supply of fire extinguishing agents or anything like that, as is the case with APS.

As the name implies, the APZ usually uses systems that are activated when a fire occurs to protect against it, for example, by extinguishing the fire. Such systems include sprinkler fire extinguishing systems, a gas fire extinguishing system, or a foam fire extinguishing system. Automatic fire suppression systems are typically reserved for high-risk areas such as personnel shelters. Because an APS system typically contains some form of consumable, such as water or another fire-fighting agent, some sort of reservoir or container is required, as well as a distribution system. APL is generally more complex than PPP, but may be more effective.

For an oil and gas platform, the integrity of equipment and pipelines containing hydrocarbons is usually provided by a combination of depressurization (ie venting of hydrocarbons) and BPP. The purpose of this is to allow personnel to safely escape from the adjacent fire zone in an emergency and then evacuate the installation personnel. The first stage is usually short, on the order of 5 minutes, but evacuation by a lifeboat of 25 people or more takes time, usually 40-60 minutes. This means that the fire must not be allowed to escalate to such an extent that the safe assembly area close to the lifeboats is endangered, i.e. containers or pipelines must not explode at elevated pressure.

According to a first aspect of the invention, there is provided a method for optimizing fire protection for an offshore oil and gas platform comprising equipment and piping associated with an oil and gas installation, the method comprising: making the platform capable of providing an evacuation time of no more than 15 minutes using one or more evacuation routes through a gangway or bridge that allow personnel to board the vessel or other platform; determining the maximum evacuation time for the platform; risk assessment for personnel using the evacuation route(s) in accordance with the established maximum evacuation time in case of fire; and providing passive fire protection to equipment and/or piping on the platform to prevent the development of a fire that would pose a risk to personnel on the escape route(s) during a specified maximum evacuation time.

This method makes it possible to optimize the degree of fire protection in such a way that it can be implemented at a minimum level based on a certain maximum evacuation time. In accordance with this method, a small and compact platform with a minimum degree of fire protection can be developed. Of course, a safe platform can easily be provided with additional fire protection over the proposed optimized fire protection, but the inventors have realized that a significant increase in efficiency is possible using this optimization method. In the preferred embodiment of the invention, passive fire protection can only be provided to the extent required to prevent the development of a fire that creates a risk to personnel on the escape route(s) during the specified evacuation time. Thus, the platform may lack additional passive fire protection. In the preferred embodiment, there is no active fire protection at all. By minimizing the degree of fire protection, the maintenance required for fire protection and the space required on the platform can be minimized. In addition, installation costs are reduced. The inventors took the non-obvious step to provide fire protection,

- 1 041077 optimized on the basis of evacuation and effectively allowing the sacrifice of equipment on the platform in the rare event of a fire, since, provided that the platform remains safe for evacuation, the further development of a fire may not be limited by fire protection.

In exemplary embodiments of the invention, the platform is an uninhabited platform, such as an uninhabited production platform, an uninhabited wellhead platform, or a combined uninhabited wellhead and production platform. In other words, it is a platform that has no permanent staff and can only be occupied by staff for certain operations such as maintenance and/or installation of equipment. An uninhabited platform may be a platform that does not require the presence of personnel for the platform to perform its normal functions, for example, day-to-day functions related to the work of draining, loading and transferring oil and/or gas products on the platform. When developing an uninhabited platform, it is of particular advantage to minimize maintenance hours, since the need for personnel on the platform is then minimized. Therefore, there is a relationship between the distinctive characteristic of the uninhabited platform and the optimization of fire protection.

An additional relationship arises from the inventors' awareness of the fact that an uninhabited platform can be operated on the basis that personnel, whenever they are present on an uninhabited platform, must be provided with direct access to the platform and exit from the platform through a ladder or bridge required in the way. Thus, an uninhabited platform can easily meet the requirement for a ladder or bridge, since it can either be connected to another platform, for example, to personnel leaving the platform via a bridge, or it can only be attended by personnel when a ship is present that provides transportation. personnel and provides part of the evacuation route(s). Thus, the method may include an escape route(s) using a so-called Walk to Work (W2W) system, such as by using a ladder from a maintenance vessel.

Where the method involves the use of a bridge to access another platform, the other platform may typically be connected to the same oil and gas installation, and may be the same type of platform or a different type of platform. For example, the platform to be evacuated may be a production platform, while another bridged platform may be a wellhead platform. In some cases, both platforms may be uninhabited.

The length of the bridge can be set to provide a safe distance for evacuation, although it is anticipated that other factors will require the bridge to be of sufficient length and likely to be longer than required. For example, the distance between platforms may be required to be greater than a certain minimum value based on the safe navigation of ships. The length of the bridge may be about 50 m or more, if necessary, about 75 m or more.

An uninhabited platform may be a platform that does not provide facilities for personnel to stay on the platform, for example, there may be no shelters for personnel, toilets, potable water, and/or personnel-operated communications equipment. In addition, the uninhabited platform may not have a helipad and/or lifeboat, and preferably, in normal use, it can only be accessed by a ladder or bridge, for example, through the Walk to Work (W2W) system, as described higher.

An uninhabited platform may alternatively or additionally be defined based on the relative amount of time that personnel need to be on the platform during operation. This relative amount of time can be defined, for example, as the required number of hours of maintenance per year, and an uninhabited platform may be a platform requiring less than 10,000 hours of maintenance per year, if necessary, less than 5,000 hours of maintenance per year, possibly less than 3,000 hours maintenance per year. Of course, there is a clear relationship between reducing the required maintenance hours and minimizing fire protection, among other things. The present method has been developed under the general principle of minimizing the amount and complexity of equipment on an uninhabited platform, thereby creating the smallest and most cost effective platform for this functionality in terms of performing a function on an oil and gas installation. When platform size reduction is combined with the proposed method, additional benefits are realized as evacuation time is reduced and thus also the amount of passive fire protection required by this method is reduced.

The short platform evacuation time, as in the proposed method, includes cases where a ship or other platform is connected to the platform whenever personnel are on it, and thus allows an innovative approach. This approach can be further developed with a platform optionally containing no hydrocarbon inventory depressurization mechanism in the event of a fire, or in some cases no depressurization mechanism at all. In some cases, it may be useful to provide a non-burning gas venting system for maintenance use. Those skilled in the art will appreciate that the platform may

- 2 041077 be capable of slow depressurization for use in maintenance (e.g. over a period of minutes or hours) while not being able to depressurize in an emergency, which must occur at high speed with the release of a large amount of hydrocarbons in a short period time, for example within a few seconds. In the exemplary methods, there is preferably no emergency depressurization and thus no flare, in particular no hot flare and preferably no cold flare. For example, there may not be a large diameter cold chimney. The lack of pressure relief, such as flaring, can further reduce the size of the platform, and although this poses an additional risk in the event of a fire developing, the small size and short evacuation time means that the risk to personnel is eliminated. Thus, the method may include leaving the equipment and pipeline under working pressure and preferably isolating them from wells that are located under water or on a separate structure, and/or from pipelines containing large reserves of oil or gas. For example, shut-off valves may be located at appropriate locations. Equipment and piping are not depressurized to atmospheric pressure in the event of a fire, but instead the system is left at operating pressure. The pressure may change as a result of the operation of other equipment, such as shut-off valves, described below, and/or a drain tank, etc.

In the event of a fire, the time to increase in intensity can be reduced compared to a similar platform with emergency depressurization. The working pressure is not released, which means that the stress in the pipe will remain high or increase, while the tensile strength of the material will decrease when heated in a fire. Therefore, rupture will occur earlier and at a higher pressure, which will increase the intensity of the fire faster than in the case of a depressurized system. However, when using the above method, this shorter time to break is acceptable. Due to the short evacuation time, the crew and maintenance vessel will still be at a safe distance when there is an increase in fire intensity. Some pipes and/or equipment will require passive fire protection to extend the time to increase in fire intensity and allow evacuation, but as described above, the amount of passive fire protection can be kept to a minimum.

The escape route(s) may include different routes from different locations on the platform to the exit point from the platform via a ramp or bridge. A platform may have only one ladder or bridge, which is thus common to all escape routes. In the case of a ship connecting to the platform via a ladder, the escape route may include boarding the ship and moving the ship away from the platform to a safe distance. In the case of a bridge, for example, to another platform, the escape route may include crossing part or all of the bridge to a safe distance. In determining the escape route(s), the method may include considering all possible locations for personnel on the platform and the route(s) that these personnel may use to leave the platform via a ramp or bridge. Determination of escape routes may include taking into account the routes required to pass decks, climb and/or descend stairs, ascend and/or descend vertical ladders, descend rescue trays and/or avoid obstacles. Obstacles may include equipment permanently on the platform with a location or a possible location that may block some routes, such as a crane that may prevent progress on a preferred escape route at some locations. In addition, obstructions may include temporary objects, such as objects being loaded onto or off the platform during installation or maintenance. The determination of evacuation routes may also include consideration of routes that may not be available if injured personnel are evacuated. The method may include determining a plurality of possible evacuation routes for different personnel locations on the platform.

The method relates to a platform with an evacuation time of no more than 15 minutes. Therefore, this imposes some restrictions on the size of the platform, as well as on the accessibility and length of the escape route(s). The method includes determining a maximum evacuation time for the platform, which results in no more than 15 minutes, and preferably less than this, for example, the platform can be configured to provide a maximum evacuation time of 10 minutes or less, if necessary, about 7 minutes or less. Reducing the maximum evacuation time can be accomplished by reducing the size of the platform decks, minimizing the height between decks, reducing the number of decks, arranging the decks to provide direct access to the exit from each deck in the direction of the evacuation route, and so on. Those of skill in the art will appreciate that variables related to maximum evacuation time can be controlled during platform design and layout, especially when the focus is on minimizing the amount of equipment available.

One possibility to minimize the size of the platform is to use a single framework

- 3 041077 decks. In an example of this type, an offshore uninhabited wellhead platform comprises: riser suspension equipment for connection to at least one riser to allow hydrocarbon fluids to flow from at least one well; and process equipment for processing hydrocarbon fluids to produce processed or partially processed hydrocarbon fluids for storage and/or transportation to another facility, with all process equipment located on the same process deck of the platform.

With this layout, the platform is an uninhabited platform and has essentially one main deck. In the preferred embodiment, the platform may be a single-deck platform containing one service deck and no additional decks, in addition to the possible upper open deck and/or lower level of access for maintenance, as described below. All process equipment on the platform is located on the same process deck and thus everything can be placed essentially in the same plane. This is in clear contrast to many known layouts that use multiple decks, as mentioned above. Reducing the number of decks simplifies platform design and saves costs and material consumption, as well as reducing evacuation time. Placing all process equipment on one process deck further simplifies the platform layout and can allow for easier platform automation. These simplifications are related to the additional proposed feature that the platform is uninhabited (i.e. it normally operates without the presence of personnel, as described below), since a simpler platform reduces the need for maintenance operations, and the presence of one technological decks for all process equipment can facilitate easier maintenance automation. For example, to move materials, such as spares or consumables, across a single haul deck, one remotely operated material handling system could be provided to move items horizontally across a single haul deck, requiring only a limited vertical direction, since the floor level for all process equipment can usually be in the same plane.

In exemplary embodiments of the invention, one process deck is the main deck of the platform, and there are no other decks for equipment related to the processing or preparation and transportation of hydrocarbon fluids. For example, there may be no decks other than one or more decks provided for the purpose of providing weather protection, material handling, and/or access to one process deck.

Process equipment may include equipment for the treatment or partial treatment of hydrocarbon fluids, such as equipment for separating and treating water for re-injection, equipment for separating hydrocarbons and/or re-injecting gas, for example, by means of an ESP. The platform may contain auxiliary equipment necessary for the operation of the wellhead platform, and some or all of this auxiliary equipment may be located on the same processing deck along with the processing equipment. For example, the platform may include an electrical cabinet and/or a hydraulic cabinet to house the electrical and/or hydraulic control system for the wellhead platform, and this cabinet is preferably located on the same process platform. Exemplary embodiments of the invention use an electrical system rather than a hydraulic system to provide minimal maintenance and reduce the need for personnel on the single deck platform.

The determination of the maximum evacuation time can be carried out on the basis of determining the evacuation route that requires the greatest time for its passage, and finding the evacuation time for this route. The method may include estimating the evacuation time and/or path length for all evacuation routes to determine the evacuation route with the longest evacuation time. The evacuation time can be calculated by evaluating the nature of each part of the evacuation route, establishing the time required for a person to complete each part of the evacuation route, and summing these times. For example, an escape route may require personnel to cross one or more decks, ascend or descend one or more flights of stairs, and pass a ladder or bridge. In the case of a ship-assisted evacuation, the evacuation route may include boarding the ship, unmooring the ship from the platform, and moving the ship away from the platform to a safe distance. The time it takes for a person to complete each part of the route can be based on the length/distance of the route and on the given speed for different types of route. Preferably, the speed is calculated based on the evacuation of the injured person. If necessary, the speed can be calculated based on favorable weather conditions. In the case of an uninhabited platform, personnel will not climb the platform in inclement weather and therefore there is no need to take into account inclement weather to calculate the evacuation rate. Speeds may be based on past experience and/or empirical calculations for travel speed

- 4 041077 people.

The evacuation time may take into account the time required for all personnel on the platform to leave the platform. Several employees may want to use the same evacuation route or the same part of the route at the same time. For example, there may be a queue to board a ship. The maximum evacuation time may be determined based on the maximum number of people on the platform and may take into account the time required for that number of people to complete all defined stages of the evacuation route, such as using a ladder, boarding a ship, etc. The method may include a platform having a maximum limit on the number of personnel present. For example, no more than 20 people can be on the platform at any time, no more than 15 people if necessary, and in some cases no more than 10 people. The method may include setting a maximum limit on the number of people allowed on the platform to thereby control the time of evacuation.

In addition to the time required to travel from a location on the platform to a safe distance from the platform along an escape route, the method may also include adding time for personnel to evaluate and understand the situation before deciding to leave the platform. Since the platform is very limited and therefore it does not take much thinking to determine the best escape route, this time may be as little as a few seconds, for example no more than 15 s or no more than 10 s. Additional time may be added for personnel to assess injuries to other employees and take appropriate action before evacuating with injured employees. The maximum evacuation time may include the time for these reflections, as well as the time required to complete the evacuation route.

The method may include using in the calculation a speed for a person crossing the deck, for example a speed in the range of 0.3 to 0.7 m/s for an injured person evacuating across a flat deck, if necessary, a speed in the range of 0.4 to 0.6 m/s, e.g. speed 0.5 m/s. The same speed can be used for an injured person crossing a flat ladder or bridge. If the escape route contains an incline, such as a ramp, then an adjusted speed may be used. The method may include using in the calculation the speed for the injured person evacuating the ascending or descending stairs, for example, a speed in the range from 0.1 to 0.3 m/s for standard size stairs, for example, a speed of 0.2 m/s. The method may include using in the calculation a speed for an injured person evacuating an ascending or descending vertical ladder, for example a speed in the range of 0.05 to 0.2 m/s, such as a speed of 0.1 m/s. Standard size marching stairs can be defined as stairs with a maximum slope not exceeding 38° and step heights in the range of 12-22 cm. unmooring of the ship from the platform, etc., and this time can be determined based on past experience and/or tests. If a vessel is involved, the method may include using the speed and/or a set time to move the vessel to a safe distance. This speed and/or time may be determined based on favorable weather conditions for the same reasons as described above.

The maximum evacuation time can be determined based on the steps described above and then used in the risk assessment and determination of the required passive fire protection. The risk assessment step for personnel using the escape route(s) in accordance with the defined maximum evacuation time in the event of a fire may include determining the likelihood of an increase in fire intensity that could affect the escape route(s) within the evacuation time. This may include taking into account the expected dynamics of personnel evacuation along the evacuation route(s). For example, it may be acceptable to increase the hazard level at the start of an escape route after sufficient time has elapsed for personnel to leave the surrounding area. The method includes providing passive fire protection for equipment and/or pipelines on the platform to prevent an increase in the intensity of the fire, creating a risk for personnel on the evacuation route(s) during the established evacuation time. This step may include providing passive fire protection to the extent necessary to eliminate the risk to personnel on the escape route(s) during evacuation, and, if necessary, the method may include only providing passive fire protection to that extent. For example, if there is a risk of an increase in fire intensity during the maximum evacuation time due to a rupture of any pipeline that is located close to the escape route or that could affect the escape route, then passive fire protection may be provided to limit the temperature increase of the pipeline during a fire and/ or to increase the strength of the pipeline to make it more resistant to rupture. In an alternative or additional embodiment of the invention, if there is a risk of an increase in fire intensity during the maximum escape time due to hydrocarbons that are in certain equipment near the escape route or which may affect the escape route, then passive fire protection may be provided to limit the increase temperature of the equipment during a fire and/or to protect the equipment from elevated temperatures to make it more resistant to hydrocarbon ignition and/or equipment explosion. Such equipment may include compressors, scrubbers, coolers, metering devices, valves, and so on.

Another factor of the known fire protection is the prevention of risk to the stability of the structure of the platform. This may also provide advantages to the proposed method, although it should be noted that in some cases an alternative decision may be made to completely sacrifice the platform for absolutely minimal fire protection, despite the risk to the structure of the platform. In the case of a relatively compact platform, even if there may be no depressurization, it is usually found that with appropriate isolation and therefore containment of hydrocarbon reserves, said hydrocarbon reserves can be small enough to allow them to burn out before risking the stability of the platform structure, avoiding this need to add any additional fire protection. Thus, in some instances, by isolating hydrocarbon reserves, the method provides optimized fire protection for both the protection of evacuees and the structure of the platform.

The time limit for evacuation, combined with the rate at which personnel can move during evacuation, places a limit on the size of the platform. The geometry and layout of the platform can be determined based on this dimension. In an alternative or additional embodiment, the size and layout of the platform may have other restrictions. In the latter case, the platform may have five or fewer decks, minimizing the time required to move between decks. In an alternative or additional embodiment, the maximum vertical distance for movement between decks during evacuation is not more than 40 m, preferably not more than 30 m. Typically, this is the distance between the uppermost deck and the lower deck from which personnel can leave the platform, such as lower deck 106 or spider deck 102. Thus, the vertical extent between the uppermost deck and the deck from which personnel can leave the platform can be no more than 40 m, preferably no more than 30 m. Decks can have a maximum length and/ or a width of less than 30 m, optionally less than 25 m, and in some examples less than 20 m. For example, the largest deck(s) may be a square or rectangle with a length and width of less than 25 m, or optionally less than 20 m.

Distinctive characteristics of a single-deck platform.

According to a second aspect of the invention, there is provided a platform for an offshore oil and gas installation, comprising equipment and piping associated with the oil and gas installation; gangway and/or bridge for connecting the platform to the vessel and/or other platform; and passive fire protection for at least some equipment and/or pipelines; moreover, the platform is configured to provide an evacuation time of not more than 15 minutes using one or more evacuation routes through a ladder or bridge that allow personnel to get onto the ship or onto another platform; and moreover, passive fire protection is installed on the equipment and/or pipelines to prevent the development of a fire that would create a risk to personnel on the evacuation route (s) during a certain maximum evacuation time.

This platform may be a platform optimized in accordance with the method according to the first aspect, and may contain features in accordance with any of the additional features set forth above. Passive fire protection may only be provided to the extent necessary to prevent the development of a fire that poses a risk to personnel on the escape route(s) during the specified evacuation time, and there may not be additional passive fire protection on the platform. In the preferred embodiment, there is no active fire protection at all.

In exemplary embodiments of the invention, the platform is an uninhabited platform, which may be the same as described above. An uninhabited platform may not provide facilities for personnel to stay on the platform, for example, there may be no personnel shelters, toilets, potable water, and/or personnel-operated communications equipment. In addition, the uninhabited platform may not have a helipad and/or lifeboat and may preferably only be accessed in normal use by a ladder or bridge, such as through the Walk to Work (W2W) system as described. higher.

If necessary, the platform may not have a pressure relief mechanism for the platform's hydrocarbon reserves in the event of a fire or, in some cases, may not have any pressure relief mechanism. Thus, for example, there may not be a torch. As described above, shut-off valves may be located at appropriate locations to isolate the platform to prevent fire from spreading to hydrocarbons outside the platform.

The evacuation route(s) may be as described above and thus may include different routes from different locations on the platform to the exit from the platform via the gangway.

- 6 041077 or bridge. The maximum evacuation time for a platform may be obtained as described above, and the evacuation time for a given escape route may be determined as described above.

The time limit for evacuation, combined with the rate at which personnel can move during evacuation, places a limit on the size of the platform. The geometry and layout of the platform may be determined based on this size and/or based on absolute size limits. Thus, a platform may contain five decks or less. In an alternative or additional embodiment, the maximum vertical distance for movement between decks during evacuation is not more than 40 m, preferably not more than 30 m. Typically, this is the distance between the uppermost deck and the lower deck from which personnel can leave the platform, such like a lower deck or a spider deck. Thus, the vertical extent between the uppermost deck and the deck from which personnel can leave the platform may be no more than 40 m, preferably no more than 30 m. Decks may have a maximum length and/or width of less than 30 m, if necessary less than 25 m. m and in some examples less than 20 m. For example, the largest deck(s) may be a square or rectangle with a length and width of less than 25 m, or if necessary, less than 20 m.

In the following, specific embodiments of the present invention will be described in more detail, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 and 2 are schematic drawings depicting an offshore field development plan;

fig. 3 is a perspective view of a three-dimensional model of an exemplary platform with the top rotated 45° relative to the supporting base;

fig. 4 is a vertical sectional view of another exemplary platform as viewed from the north;

fig. 5 is a plan view of an exemplary spider deck for the platform shown in FIG. 4;

fig. 6 is a plan view of an exemplary emergency stop valve deck for the platform shown in FIG. 4;

fig. 7 is a plan view of an exemplary lower deck for the platform shown in FIG. 4;

fig. 8 is a plan view of an exemplary lower tier mezzanine deck for the platform shown in FIG. 4;

fig. 9 is a plan view of an exemplary process deck for the platform shown in FIG. 4; fig. 10 is a plan view of an exemplary upper open deck for the platform shown in FIG. 4. The following is described in the context of a possible development of the 10 field.

At the first remote site A, a subsea production system (SPS) with six wellheads is proposed. Approximately 12 km away at the second remote site B, an Unmanned Wellhead Platform (UWP) 14 and an Unmanned Processing Platform (UPP) 16 are proposed.

The distance between remote site A and remote site B is approximately 12 km, and the distance from remote site B to the connection point on the main pipeline is approximately 34 km. In FIG. 1 and 2 are schematic representations of piping systems. The sea depth at both remote site A and remote site B and the main node area ranges from 100 to 110 m, and the seafloor bathymetry is generally flat, without any significant distinctive features or irregularities.

Oil, gas, and water from the formation reservoir at remote site A is produced by the SPS 12. Downhole fluid is transported through an insulated tubing 18 of a pipe-in-pipe system with trace heating to remote site B. The subsea and surface UPP facility 16 at remote site B is protected from high pressure in closed well with a subsea high-integrity pressure protection system (HIPPS) 20 .

Oil, gas and water from the remote site B reservoir is produced by UWP 14. The UPP subsea and surface facility 16 is protected from the high shut-in well pressure by the surface HIPPS system 22 at UWP 14.

Pressurizing water injection is scheduled for both remote site A and remote site B formation reservoirs via respective water injection conduits 24, 26.

Production fluid from remote site A and remote site B is mixed before subsea separator 30. Subsea separator 30 is a three-phase separator operating initially at approximately 40 bar. The temperature in the separator 30 is high (90° C.) and a good separation is expected.

Oil and water exiting separator 30 is measured by multiphase flow meter 32 and transported to main assembly 34. The receiving pressure at main assembly 34 is maintained at the same level as that of subsea separator 30 to avoid flashing and multiphase flow in the export or inlet pipeline. heater in the main node 34. The oil is only partially stabilized in the subsea separator 30, and further stabilization in accordance with the requirements of the pipeline

- 7 041077 transport is assumed in the main node 34.

The subsea separator 30 and pumps (not shown) are designed as a subsea separator and booster station (SSBS) 29, which is located as close as possible to the UPP 16 to minimize condensation and mist eliminators in the gas pipelines from the separator 30 to UPP 16.

UPP 16 is connected to main assembly 34 via umbilical 50. The umbilical provides remote control of UPP 16 operations as well as SPS 12, UWP 14 and SSBS 29 operations via optional umbilicals 52, 54, 56. In addition, optional umbilicals 52, 54, 56 use to supply any required power and chemicals to be supplied from UPP 16 to SPS 12, UWP 14 and SSBS 29.

Gas at a pressure of 40 bar is supplied from the separator 30 to the upper inlet cooler 36 of the UPP platform 16 through a special riser 38. The inlet cooler 36 contains a shell and tube heat exchanger with sea water cooling. Triethylene glycol is injected into the gas to inhibit hydrate formation before the gas is cooled to 20° C. in a shell and tube intercooler 36 with sea water cooling.

Condensed water and hydrocarbons are removed in a scrubber 37 located in a subsequent process step. The liquid from the scrubber 37 flows under the action of gravity back into the subsea separator 30 through a special riser 40.

The gas from scrubber 37 is then compressed to about 80 bar in a first stage compressor with an outlet temperature of about 80°C. The temperature should ideally be as low as possible to reduce the amount of glycol required for dehydration.

The maximum crikondenbar pressure of the transported gas is 110 bar. Krikondenbar is the pressure below which no liquid is formed, regardless of temperature. Krikondenbar is a property of a gas. Krikondenbar is determined based on the conditions in the inlet scrubber 37.

The pressure in the scrubber 37 is determined based on the pressure in the subsea separator 30. The low pressure in the separator 30 results in a reduction of associated gas in the transported oil and is needed at some point in time to meet production schedules. However, at lower pressures, the required compression work and power consumption will increase. The separator 30 initially operates at a pressure of about 40 bar, but the pressure will be reduced to 30 bar or even lower towards the end of its life.

The temperature in the scrubber 37 is determined by the outlet temperature of the inlet cooler. A lower temperature corresponds to a lower krikondenbar. The hydrate formation temperature is about 15°C, and the interval of 5°C provides a minimum temperature at the outlet of the cooler of 20°C.

The gas from the scrubber 37 is then dehydrated by adsorption drying of the gas with glycol to meet pipeline transportation requirements. For example, for gas transported to the Statpipe system, the maximum water content is 40 mg/cm ³ .

After dehydration, the gas is compressed to the required transport pressure. For example, the maximum working pressure in a Statpipe Rich Gas pipeline is 167 bar. The required conveying pressure depends on the volumes of gas to be dispensed and the selected operating pressure in the pipeline, and may be lower than the indicated maximum pressure.

The gas is metered and metered as required in a dedicated metering unit before entering the transport riser and the transport gas line 44.

In one example, the temperature at the outlet of the compressor is about 80°C at a pressure of 167 bar. However, the gas is cooled in a 45 km uninsulated gas transport pipeline 44 and the temperature of the gas is well below the maximum operating temperature for the Statpipe when it reaches the connection point.

The selected design of the UPP 16 facilitates unmanned oil and gas treatment at remote site B. The combination of subsea treatment and surface treatment on the UPP 16 platform can maximize performance and minimize capital and operating costs.

UPP 16 contains a steel support base structure. The support base 46 is square in shape with a spacing of 14 meters between the support columns 114. The support base is rotated 45° relative to the northern part of the platform to optimize the weight-to-size ratio for the top 48 so that the upper decks 48 are at an angle of 45° to the square of the support base 46 as shown in FIG. 3. As an example, a possible layout of the UPP is shown in the vertical sectional view of FIG. 4 and in plan view for each of the deck levels in FIG. 5-10 which show the spider deck 102, the emergency shutdown valve (ESDV) deck 104, the lower deck 106, the lower deck mezzanine deck 108, the service deck 110, and the upper open deck 112, respectively.

The UPP 16 uses a four-pile symmetrically inclined support base 46 to support the top 48. The top 48 has a section of 19.8 x 19.8 m in the main span of the structure and is rotated relative to the support base 46.

The umbilicals are pulled onto the platform 48 by a winch located on the upper open deck 112, and for this purpose, a groove for the umbilical cable and a reserved space for it is provided in the center of the platform 48. The slot and reserved space can be used for other purposes on the modular platform after the umbilicals have been rolled up.

SSBS 29 is located on the seabed within the substructure 46. The subsea separator 30 is used in place of the surface solution on the UPP 16, as the surface solution would require an additional level on the UPP 16 due to size and weight requirements.

Separator 30 is based on a symmetrical design with a central top inlet and a top outlet at both ends, combined with cyclones for gas finishing. Likewise, oil and water outlets are at the bottom inside and outside the respective baffles. Subsea separator 30 is operated by several separate control loops.

The levels in separator 30 are measured using a profiler level detector system. The water level control controls the speed of the water injection pump, and the oil level controls the speed of the transfer pump. The pressure in the subsea separator 30 is controlled by the speed of the first stage compressor (suction pressure control). The control loops will be closed to the master node 34 via fiber optic cables in the umbilicals 50, 56.

Platform 14, 16 is oriented based on the prevailing wind direction. For example, with prevailing winds from north to south and from west to east, processing equipment should be located on the east and southeast side of the platform to ensure good natural ventilation.

As noted above, the platform layout preferably utilizes a pivoted top 48 as shown in FIG. 3, while the upper decks 102, 104, 106, 108, 110, 112 are rotated by 45° with respect to the support base 46. In this case, the upper decks 102, 104, 106, 108, 110, 112 can be oriented to the cardinal points so that the sides of the square decks 102, 104, 106, 108, 110, 112 are facing north, south, east and west, and the base 46 is rotated 45° relative to them, so that the corners of the base 46 are facing north, south , east and west.

Spider deck 102 is located at a height of 20 m above sea level. An exemplary arrangement is shown in Fig. 5. The spider deck 102 includes three landings and landings 122 located at the north corner of the substructure 46 when the maintenance vessel (SOV) is on the north and east side of the UPP platform 16, and at the western corner of the substructure 46, when the SOV is on the west side of UPP 16.

For the site 122 disembarkation and landing of personnel in the northern corner defined area 126 gathering. The collection area can be located below the module and close to the north staircase leading to the decks above. A temporary rescue chute 124 is located at the joint northeast landing 122 for disembarkation and disembarkation of personnel.

It is likely that the preferred side for the SOV is the east side of UPP 16 due to the prevailing wind direction. For this reason, a storage area 128 for handling materials is located on this side. Storage area 128 is 8x5 m. From storage area 128 stairs lead to deck 104 ESDV. Access and evacuation routes are provided between the drop-off and drop-off areas 122 and the storage area 128.

A device for hanging the pipeline and risers, which requires a 3D or 5D bend, is located on the spider deck 102. In addition, it is likely that the umbilicals and power cables should be suspended at this level and routed directly to the terminal panels.

ESDV deck 104, which may have the layout shown in FIG. 6 is located 4 m above the spider deck 102. The piping entering the UPP 16 from underwater runs inside the substructure 46. For piping with an emergency stop valve, this ESD valve should be located on deck 104 of the ESDV. The piping requirements are terminated at the ESD valve. The piping containing the ESD valve must be designed in accordance with ASME Design Code B31.3 Process Piping. The ESD valves for the 16" gas transmission line and the 16" process line from the subsea separator are the largest valves on this deck 104, and the valves will likely set the deck height prior to obtaining a material handler. On the north side of this deck 104 and adjacent to the umbilical slot are umbilical connection cabinets (Umbilical Top End Units (TUTU)). On the west side of this deck are two seawater pumps containing strainers and a hydraulic unit, as well as a platform to house the seawater lift pump.

Storage area 130 ESDV has a temporary removable open drain tank. Size

- 9 041077 (5x2.5 m) of storage area 130 provides the ability to load and unload material when the drainage tank is in storage area 130. The crane operator will have direct visibility and good accessibility using the crane 132 of the upper open deck.

The triethylene glycol circulation pump (24P0002) is located on the east side of the deck and below the second stage scrubber to provide sufficient pump suction height (6 m). Access to the aforementioned lower deck 106 is provided from the north and south ends of the ESDV deck 104 by ladders.

An example of the layout of the lower deck 106 is shown in FIG. 7. In this example, lower deck 106 is located 6 meters above ESDV deck 104. Access to the deck 106 of the lower tier is carried out by a flight of stairs on the north side from the technological deck 110, located above, and from the deck 104 ESDV, located below. The staircase is connected to the storage area 130 of the lower deck. The south staircase above and below the area leads to the bridge. From north storage area 134 to bridge 136 on the south side, there is a main evacuation route connecting ladders through decks 102, 104, 106, 108, 110, 112 of the platform. Bridge 136 is 75 m long and connects the UPP 16 platform to the UWP 14 platform.

On the north side is a storage area 134 (6x4 m) which is designed to take the weight and size of the main power transformer located near the storage area 134. Transformers are the largest and heaviest equipment on this deck 106. Due to the maintenance of the overall equipment, the dimensions loading and unloading routes are designed for this overall equipment. The high voltage transformers are located in a naturally ventilated area, which is closed during normal use and accessible only to authorized personnel.

On the northwest side of deck 106 is the ventilated compressor's Variable Frequency Drive (VFD) compartment. Access to the VFD compartment is from the process area and air lock at the center of this deck 106 or from the north end of the compartment. Larger items to be removed from the compartment are removed through the north aisle and moved to storage area 134.

The Heating, Ventilation and Air Conditioning (HVAC) section is located on the southwest side with access hatches to the east and south, and secure access is provided from the airlock used to access the electrical section of the VFD. Larger items that need to be replaced can be moved through the east aisle and sent along the material transport route to the storage area. It is assumed that the air intake for the HVAC separation is located on the west wall of lower deck 106, and the air filter pack should not exceed 25 kg to allow for manual movement.

Process equipment is located on the east side of the module containing the scrubbers, pump and custody transfer package. In the center of the module, a staircase is made to the mezzanine deck 108 to avoid passing through the local control room when accessing the local electrical room. In FIG. 8 shows an example of the layout of the mezzanine deck 108 of the lower tier.

In this example, the mezzanine deck 108 of the lower tier is located at a distance of 4.6 m above the deck 106 of the lower tier. Access to deck below and deck above is provided by north and south stairs in addition to the inside south stairs. A naturally ventilated local control room is located at the south end of this mezzanine deck 108. Access may be from the stairs at the south end or via the stairs at the northeast corner of the control room. Transport of materials can be provided by a monorail and lift 138 through the panel and into the unloading area on the southeast side and down to the east side of the bridge exit.

The local equipment room is mechanically ventilated for non-explosion-proof equipment and is provided with an air lock at the entrance from the east stairs next to the process equipment. In the north, access is provided directly to the north staircase. There is no deck above the process area and overall equipment, however a platform is provided on the mezzanine deck 108 for access to the raised part of the scrubbers.

Above the lower deck 106 and the lower deck mezzanine deck 108 is a service deck 110, which may be positioned as shown in FIG. 9. In this example, the service deck 110 is located 9 meters above the deck 106 of the lower tier. Access to the deck below is via the north and south stairs. Access to the upper open deck 112 is located on the east and west sides.

Storage area 140 (6x4m) with crane access is located at the north end of process deck 110 with a short transport route for 1st and 2nd stage compressor transformers. Each transformer weighs about 25t and must be moved with a heavy duty floating crane during installation as the SOV crane has an 8-10t limit.

- 10 041077

In this example, the upper open deck 112 is located 8 m above the service deck 110 and may have the layout shown in FIG. 10. From this deck, access and egress is possible via stairs on the east and west sides of the unit and down to deck 106 of the lower tier. The main equipment on the upper open deck 112 is a heat exchanger with an intercooler and inlet gas heat exchangers. Dual heat exchangers are stacked on top of each other in the southwest area of the deck. A unit with chemical tanks and a pump may be required while waiting for chemicals to be delivered from the OFC via umbilical.

The vent pipe 142 is located in the southeast corner due to the prevailing wind direction and to be located close to the process equipment to ensure the shortest possible piping. The overpressure valves for the vent line are located close to the vent pipe 142. In this example, the pipe size is 1.5 x 1.5 x 10 m. The vent pipe 142 is used for cold ventilation during certain procedures and is not used for pressure relief in the event of a fire. Vent stack 142 may be used to depressurize methane through cold stack 142 during barrier testing and maintenance operations that require depressurization. It should be noted that there is no torch for this platform 16, which is a significant difference from the traditional design. In the event of a fire, there is no emergency depressurization, and instead the pipeline and equipment on platform 16 are isolated from wells and large volumes of hydrocarbons in connected external pipelines by means of valves, and then left at operating pressure. As described above, this creates an additional risk in terms of increased fire intensity, but this risk can be managed by limiting the size of the platform 16 and therefore minimizing the evacuation time, as well as by adding passive fire protection, as described below.

A platform crane 132 is located in the northeast corner to provide good access to all storage areas 128, 130, 134, 140 on the various decks below. This crane has an 18 meter reach and access to storage areas 128, 130, 134, 140 and the SOV is provided by platform 16.

Goods lifted by the SOV into the spider deck storage area 128 can be picked up by the platform crane 132 and moved to the local storage area 130, 134, 140. on the north side and between two storage areas 128, 130 on the east side.

The area 146 on the upper open deck 112 may be dedicated to helicopter landing, although it should be understood that the platform design does not provide for a helipad.

Material from the unloading areas on the deck 106 of the lower tier can be moved to the northern storage area 134 using a cart. Likewise, manually liftable equipment on all decks can be moved by trolley to a local storage area for onward transport.

The primary option for moving equipment to/from UPP 16 is the SOV crane used during routine scheduled visits during the operational phase. An SOV crane is used to transport cargo and equipment to and from the platform to the lowest storage area 128 on the spider deck 102. This is 20m above sea level on the UWP 14 platform and the UPP 16 platform. The maximum load on the SOV crane is typically 20t at a height of 20m and with a significant wave height of up to 3m. Loads of less than 25kg can be moved by team members within W2W (SOV) systems.

Cargoes up to 3 tons may alternatively be moved by helicopter to storage area 146 on the upper open deck 112. The upper open deck 112 may contain an unloading area 146 for helicopter cargo and a personnel recovery area for leaving the platform in a situation where there is no access to the SOV. .

Internal lifting on the UPP 16 is performed by a jib crane 132 which is mounted on the upper open deck 112 as noted above. In this example, the jib crane 132 has a lifting capacity of 10 tons at a distance of 18 m along the jib. A similar design can be used for UWP 14. Transportation to/from storage area 128 on spider deck 102 to platform decks 104, 106, 108, 110, 112 can be accomplished with platform crane 132 to storage areas 130, 134, 140 outside decks 104, 106, 108, 110, 112. This crane 132 is for boarding only and all storage areas 128, 130, 134, 140, 146 are within reach of crane 132. Preferably, this crane 132 is only needed when favorable weather, because in case of inclement weather, personnel do not visit platform 16. This means that there is less need for the ability of the platform crane 132 to operate in bad weather. Likewise, an SOV crane does not need to be able to operate in bad weather. For example, cranes may not be required to meet the requirements of BS EN 13852-1 for offshore operation in significant wave heights, such as operation in 5-6 m wave heights. Instead, the platform crane and SOV crane may be required to operate only in wave heights. up to 2 m.

- 11 041077

Lifting loads in excess of 10t can be handled by a separate high capacity floating crane, although equipment weighing just over 10t can be handled and transported by an SOV crane with more stringent wave height restrictions, but this will depend on the actual capacity of the crane in use. ship.

Heavier equipment components are placed in such a way that they can be picked up and transported to an external storage area where they can be picked up by a suitable crane vessel. Internal transport can be done with lifting traverses or monorail vehicles and railcars capable of carrying the appropriate load. Lifting/transport devices can be brought to the platform if necessary for the respective work.

All vertical transportation between decks is carried out by platform crane 132, at least for larger items. As an alternative lifting device for smaller items at the level of the upper open deck there are two overhead cranes 144, one serving the east side covering the storage areas on the spider deck 102 and ESDV deck 104, and the other serving the north side covering the storage areas on the technological deck 110 and deck 106 of the lower tier.

Local transportation for each item includes the use of permanently installed eyelets and monorails, as well as temporary equipment. It must be possible to install the trolley/lifts without the use of temporary scaffolding. The platform 16 is intended for internal horizontal transport of items from storage areas to/from a location where these items are needed.

The lifting equipment used is preferably of a modular and temporary design and must be stored, maintained and inspected ashore to reduce the time required for maintenance at sea. This lifting equipment can be transported to the platform via the SOV (or via bridge 136 if available). Only the jib crane 132 of the upper open deck, lifting eyes and monorails are permanently on the platform. The movable parts of a jib crane should, as far as possible, be modular and removable so that they can be stored and serviced ashore. It is preferable that only parts too heavy to be dismantled remain on the jib crane and they should be suitable for long term storage under severe conditions with minimal maintenance.

Platform 16 provides various escape routes from different locations. When establishing evacuation routes, the slowest evacuations should be used as the basis for calculating the maximum evacuation time. This maximum evacuation time is then used to determine which fire protection should be activated. Platform 16 includes passive fire protection (PFS) to ensure that the intensity of the fire does not increase until the personnel on the platform have been safely evacuated. It should be noted that the absence of a flare may increase the risk of dangerous development of a fire, since there is no pressure relief. However, the absence of a torch helps to reduce the size of the platform 16 and minimize the evacuation time. Furthermore, since platform 16 is an uninhabited platform, personnel will only be present on it with a bridge or stairway connection to the SOV located there, which means that the evacuation process can be very fast. Personnel are expected to be able to reach the stairwell within 1 minute of the initial incident, and the conservative assumption is that personnel will be on the maintenance vessel within 10 minutes.

The evacuation route(s) may include different routes from different locations on platform 16 to an exit from the platform via a ladder or bridge 136. on the ship from the platform to a safe distance. In the case of bridge 136, for example to another platform such as UWP 14, the escape route may include crossing part or all of bridge 136 to a safe distance. The determination of escape routes includes taking into account the routes required to pass the decks, ascend and / or descend the mid-flight ladders, ascend and / or descend the vertical ladders, descend the rescue trays and / or avoid obstacles. The evacuation time and/or path length is evaluated for all evacuation routes, or at least for the longest routes, to determine the evacuation route with the longest evacuation time. The evacuation time is calculated by assessing the nature of each part of the evacuation route, establishing the time required for a person to pass each part of the evacuation route, and summing the time. The time it takes for a person to complete each part of the route is based on the length/distance of the route and on the set speed for the various route types. Preferably, the speed is calculated based on the evacuation of the injured person. If necessary, the speed can be calculated based on favorable weather conditions. In the case of an uninhabited platform, personnel will not climb the platform in inclement weather and therefore there is no need to take into account inclement weather to calculate the evacuation rate. Speeds may be based on past experience and/or empirical calculations for human movement speed.

- 12 041077

As an example, the moving speed can be set as follows.

Evacuation of an uninjured person: 1.0 m/s for corridors (flat decks), 0.6 m/s for mid-flight stairs and 0.3 m/s for vertical stairs.

Evacuation of an injured person: 0.5 m/s for corridors, 0.2 m/s for mid-flight stairs and 0.3 m/s for vertical stairs.

The exemplary platform described above is approximately 20x20m with three full decks 106, 110, 112 and one mezzanine deck 108, plus two decks 102, 104 as part of the support base structure. The support base 46 has a size of approximately 18x18 m. The longest escape route is the route from the upper open deck 112 to the SOV. The conservative option uses a diagonal distance across the deck. Thus, the evacuation route is as follows: diagonally across the deck - 28 m, along the flight ladder from the upper open deck 112 to the bridge deck (spider deck 102) - 91 m (based on a height of 27 m and a ladder slope of not more than 38 °), and from bridge deck to SOV - 30 m.

Using the speeds given above, it is possible to determine the evacuation time for uninjured and injured personnel. For an uninjured person, the times are as follows: diagonally across deck 28 s, stairway from upper open deck 112 to bridge deck (spider deck 102) 152 s, and from bridge deck to SOV 30 s, for a total time of 210 s. To evacuate an injured person, the time is as follows: diagonally across the deck - 56 s, along the flight ladder from the upper open deck 112 to the bridge deck (spider deck 102) - 456 s, and from the bridge deck to SOV - 60 s, for a total time of 572 s .

In an alternative scenario, the evacuation route may pass through bridge 136 to an adjacent platform. By way of example, personnel are required to walk the full length of bridge 136 to be safe, in which case bridge 136 is located on lower deck 106. Thus, the evacuation route is as follows: diagonally across the upper open deck 112 - 28 m, along the stairs from the upper open deck 112 to deck 106 of the lower tier - 57 m, and from deck 106 of the lower tier through the bridge 136 - 75 m.

Using the speeds given above, it is possible to determine the evacuation time for uninjured and injured personnel. For an uninjured person, the times are as follows: diagonally across the upper open deck 112 - 28 s, along the flight ladder from the upper open deck 112 to lower deck 106 - 152 s, and across the bridge 136 - 75 s, for a total time of 199 s. For the evacuation of an injured person, the time is as follows: diagonally across the upper open deck 112 - 56 s, along the flight ladder from the upper open deck 112 to deck 106 of the lower tier - 287 s, and across the bridge 136 - 150 s, with a total time of 493 s.

The evacuation time is used to assess the risk and determine the required passive fire protection. Provide passive fire protection for equipment and/or piping on the platform to prevent an increase in fire intensity that poses a risk to personnel on the escape route(s) during the established evacuation time. The implementation of minimum fire protection includes the provision of passive fire protection only to the extent necessary to eliminate the risk to personnel on the escape route(s) during evacuation Thus, if there is a risk of an increase in fire intensity during the maximum evacuation time due to a rupture of any pipeline which is located close to the escape route or which may affect the escape route, passive fire protection is provided to limit the increase in temperature of the pipeline during a fire and/or to increase the strength of the pipeline to make it more resistant to rupture. In an alternative or additional embodiment of the invention, if there is a risk of an increase in fire intensity during the maximum escape time due to hydrocarbons that are in certain equipment near the escape route or which may affect the escape route, then provide passive fire protection to limit the increase in temperature of the equipment during a fire and/or to protect equipment from elevated temperatures to make it more resistant to hydrocarbon ignition and/or equipment explosion. Such equipment may include compressors, scrubbers, coolers, metering devices, valves, etc.

It should be noted that the system described above for optimizing fire protection can also be applied to the UWP 14 platform in a similar manner. In addition, it should be understood that the exact layout for the platform regarding the available decks and the equipment used may vary.

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Claims (18)

CLAIM 1. A method for optimizing fire protection for an offshore oil and gas platform containing equipment and pipeline associated with an oil and gas installation, including the implementation of the platform with the ability to provide an evacuation time of not more than 15 minutes using one or more evacuation routes through a ladder or bridge that allow personnel to get on ship or to another platform; moreover, the execution of the platform with the possibility of providing an evacuation time of no more than 15 minutes comprises reducing the size of the decks of the platform, minimizing the height between the decks, reducing the number of decks and / or the location of the decks in such a way as to provide direct access to the exit from each deck in the direction of the evacuation route; determining the maximum evacuation time for the platform by determining the evacuation route requiring the longest evacuation time and determining the evacuation time for this route, while the maximum evacuation time for the platform is determined using one or more of the following parameters: speed 0.3-0.7 m/ c for a person crossing the deck; speeds of 0.1-0.3 m/s for an injured person evacuating along an ascending or descending flight ladder; a speed of 0.05-0.2 m/s for an injured person evacuating via an ascending or descending vertical ladder, the set time for opening the fence, the set time for boarding the ship and / or the set time for unmooring the ship from the platform; risk assessment for personnel using evacuation routes in accordance with the established maximum evacuation time in case of fire; and providing passive fire protection for equipment and/or pipelines on the platform to prevent the development of a fire that would create a risk to personnel on escape routes during a specified maximum evacuation time. 2. The method of claim 1, wherein passive fire protection is provided only to the extent necessary to prevent the development of a fire that poses a risk to personnel on escape routes during a specified maximum evacuation time. 3. The method according to claim 2, in which the platform does not have additional passive fire protection. 4. The method according to claims 1, 2 or 3, in which there is no active fire protection on the platform. 5. A method according to any one of the preceding claims, wherein the platform is an uninhabited platform with no permanent personnel and/or the platform is an uninhabited platform and does not provide facilities for personnel to stay on the platform, for example, there may be no personnel shelters, toilets, drinking water, personnel-operated communication equipment, heliport and/or lifeboat, and/or the platform is an uninhabited platform and requires the presence of personnel for less than 10,000 hours of maintenance per year. 6. A method according to any one of the preceding claims, wherein the escape routes use the Walk to Work system. 7. A method according to any one of the preceding claims, wherein the escape routes include different routes from different locations on the platform to an exit from the platform via a ramp or bridge, the method comprising determining a plurality of possible escape routes for different personnel locations on the platform to calculate the maximum evacuation time. 8. The method according to any one of the preceding claims, wherein the maximum evacuation time is calculated based on estimating the nature of each part of the longest evacuation route, establishing the time required for a person to complete each part of the evacuation route, and summing these times; and in which the time required for a person to complete each part of the route can be based on the length/distance of the route and on the given speeds for different types of route based on the evacuation of the injured person, optionally, which in addition to the time required to move from a location to a safe distance from the platform along the evacuation route includes adding time for personnel to assess and understand the situation before deciding to leave the platform and/or adding time for personnel to assess injuries to other employees and take appropriate action before evacuating with injured employees. 9. A method according to any one of the preceding claims, comprising isolating the hydrocarbon reserves on the platform in case of fire. 10. A method according to any one of the preceding claims, wherein the platform comprises five decks or less, optionally, wherein the vertical extent between the uppermost deck and the deck from which personnel can leave the platform is not more than 40m and/or - 14 041077 in which all platform decks have a maximum length and/or width of less than 30 m. 11. A method according to any one of the preceding claims, wherein the platform does not include a mechanism to depressurize its hydrocarbon reserves in the event of a fire, and thus the equipment and pipelines on the platform remain at operating pressure in the event of a fire. 12. A platform for an offshore oil and gas installation containing equipment and pipeline associated with an oil and gas installation; ladder and/or bridge for connecting the platform to the ship and/or other platform and passive fire protection for at least some equipment and/or pipelines; moreover, the platform is configured to provide an evacuation time of not more than 15 minutes using one or more evacuation routes through a ladder or bridge that allow personnel to get onto the ship or onto another platform; moreover, the platform decks are located in such a way as to provide direct access to the exit from each deck in the direction of the evacuation route; moreover, passive fire protection is installed on the equipment and / or pipelines to prevent an increase in fire intensity that creates a risk for personnel on escape routes during a certain maximum evacuation time, while the deck of the platform has dimensions calculated taking into account the speed of 0.3-0.7 m /s for a person crossing the deck; the ascending or descending march ladder has dimensions calculated taking into account the speed of 0.1-0.3 m / s for an injured person evacuating along the ascending or descending march ladder; the ascending or descending vertical ladder has dimensions calculated taking into account the speed of 0.05-0.2 m / s for the injured person evacuating the ascending or descending vertical ladder, while the maximum evacuation time for the platform is determined taking into account the above platform dimensions, the dimensions of the ascending or descending flight ladder, the dimensions of the ascending or descending vertical ladder, the set time for opening the guard, the set time for boarding the ship and/or the set time for unmooring the ship from the platform. 13. Platform according to claim 12, made in such a way as defined in any one of claims 1-11. 14. The platform according to claim 12 or 13, on which passive fire protection is provided only to the extent necessary to prevent the development of a fire that creates a risk to personnel on escape routes during the specified maximum evacuation time, and there is no additional passive fire protection. 15. The platform according to claims 12, 13 or 14, on which there is no active fire protection. 16. A platform according to any one of claims 12-15, containing five decks or less, optionally, in which the vertical extent between the uppermost deck and the deck from which personnel can leave the platform is not more than 40 m, and / or in which all platform decks have a maximum length and/or width of less than 30 m. 17. The platform according to any one of claims 12-16, which is an uninhabited platform that does not contain permanent personnel and does not provide facilities for personnel to stay on the platform, for example, there may be no shelters for personnel, toilets, drinking water, communication equipment controlled by personnel, helipad and/or lifeboat; and/or designed in such a way that it requires the presence of personnel for less than 10,000 hours of maintenance per year. 18. A platform according to any one of claims 12-16, comprising shut-off valves configured to isolate the platform's hydrocarbon reserves from external hydrocarbon stores in the event of a fire, and/or which does not include a pressure relief mechanism for the platform's hydrocarbon reserves in the event of a fire, and thus, the equipment and pipelines on the platform remain under working pressure in the event of a fire. -