Method for evaluating oxygen concentration after gas release at gas fire extinguishing protection position of offshore platform

Abstract

The invention discloses a method for evaluating the oxygen concentration after gas release at a gas fire extinguishing protection position of an offshore platform. The method comprises the following steps: S1, calculating the required dosage according to the net volume of a room; s2, proper gas cylinder specifications are selected according to the drug dosages of different rooms, and the actual gas cylinder number is obtained through calculation; s3, calculating the oxygen concentration of the room after actual release according to the actual number of the gas cylinders; s4, if the calculated oxygen concentration is greater than 10% (vol%), an actual oxygen concentration test does not need to be carried out; s5, if the calculated oxygen concentration is smaller than or equal to 10% (vol%), actual oxygen concentration testing needs to be carried out, and if the actually obtained oxygen concentration is smaller than or equal to 10% (vol%), after corresponding measures are taken, oxygen concentration testing is carried out again till the actually measured oxygen concentration is larger than 10% (vol%). The situation of casualties caused by too low oxygen concentration due to gas fire extinguishing release is effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of offshore fire safety, and in particular to a method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform. Background Art

[0002] The clean gas fire extinguishing systems currently on the market mainly achieve their fire extinguishing function by reducing the oxygen concentration, that is, releasing a certain calculated amount of fire extinguishing agent into the fire area, forcing the oxygen concentration in the fire area to be lower than the oxygen concentration required for combustion, thereby achieving the effect of fire extinguishing. The effective fire extinguishing concentration of the relevant fire extinguishing agent has been defined and verified.

[0003] However, in the actual design process, in order to unify the specifications of shared gas cylinders, the amount of medicine released in the room will be more than the actual required release amount. For example, the required number of medicine bottles is calculated to be 7.2 bottles, but 8 bottles will actually be released. This situation is relatively common, but it may cause the oxygen concentration in the room to be too low. When the oxygen concentration in the environment is lower than 10% (vol%), fire extinguishing may cause casualties (special circumstances lead to people who fail to escape in time).

[0004] Therefore, a method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform is provided. Summary of the invention

[0005] The purpose of the present invention is to overcome the existing defects and provide a method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform, so as to effectively reduce casualties caused by excessively low oxygen concentration due to gas fire extinguishing release.

[0006] The technical solution to achieve the above purpose is:

[0007] A method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform, comprising:

[0008] Step S1, calculating the required amount of medicine according to the net volume of the room;

[0009] Step S2, selecting appropriate gas cylinder specifications according to the dosage of different rooms, and calculating the actual number of gas cylinders;

[0010] Step S3, calculating the actual oxygen concentration in the room after release according to the actual number of gas cylinders;

[0011] Step S4, if the calculated oxygen concentration is greater than 10% (vol%), there is no need to perform an actual oxygen concentration test;

[0012] Step S5, if the calculated oxygen concentration is ≤10% (vol%), an actual oxygen concentration test is required. If the actual oxygen concentration is ≤10% (vol%), the oxygen concentration test is performed again after implementing corresponding measures until the actual measured oxygen concentration is greater than 10% (vol%).

[0013] Preferably, in step S5, the oxygen concentration test process is:

[0014] Prepare several oxygen probes and install them on the wall of the test room at a position of about 1.4-1.7 meters;

[0015] The release device in the area is activated and the drug begins to be released;

[0016] Observe and record the detection data of the oxygen probe, as well as the actual oxygen concentration during and after release.

[0017] Preferably, in step S5, the corresponding measures include:

[0018] If the room volume is very small and the original number of gas cylinders is calculated to be ≤ 1, then this room should be converted into an independent gas fire extinguishing system;

[0019] If the room volume is large and the original calculated number of gas cylinders is greater than 1 cylinder, then reduce the number of released gas cylinders by one.

[0020] Preferably, in step S5, the gas fire extinguishing system includes but is not limited to gas cylinders, main pipes and zone valves.

[0021] Preferably, in step S5, for reducing the number of released gas cylinders by one:

[0022] Retest the room for oxygen concentration after the number has been reduced;

[0023] Determine whether the oxygen concentration after release is within the range of 10% ≤ O2% < 12%;

[0024] If yes, the oxygen concentration test ends;

[0025] If not, change the gas cylinder specifications and test the oxygen concentration again until the oxygen concentration meets 10% ≤ O2% < 12%.

[0026] The beneficial effects of the present invention are as follows: the present invention calculates the required amount of medicine according to the net volume of the room; selects suitable gas cylinder specifications according to the amount of medicine in different rooms, and calculates the actual number of gas cylinders; calculates the oxygen concentration in the room after the actual release according to the actual number of gas cylinders, and determines whether it is necessary to perform an actual oxygen concentration test; if the calculated oxygen concentration is greater than 10% (vol%), there is no need to perform an actual oxygen concentration test; if the calculated oxygen concentration is ≤10% (vol%), an actual oxygen concentration test is required, and if the actual oxygen concentration is ≤10% (vol%), the oxygen concentration test is performed again after implementing corresponding measures until the actually measured oxygen concentration is greater than 10% (vol%); through this method, the situation of casualties caused by too low oxygen concentration due to gas fire extinguishing release can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a flow chart of a method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform. DETAILED DESCRIPTION

[0028] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0029] The present invention will be further described below in conjunction with the accompanying drawings.

[0030] How to reduce the damage caused by gas fire extinguishing agents to the human body is a part of fire safety that needs to be considered. Some offshore platforms use fire extinguishing agents such as Novec1230 that are less harmful to the human body, but the cost is high and the system transmission distance is relatively limited.

[0031] like Figure 1 As shown, a method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform comprises:

[0032] Step S1, calculating the required amount of medicine according to the net volume of the room.

[0033] Step S2, selecting appropriate gas cylinder specifications according to the amount of medicine in different rooms, and calculating the actual number of gas cylinders.

[0034] Step S3, calculating the actual oxygen concentration in the room after release according to the actual number of gas cylinders.

[0035] In the embodiment, the formulas used for calculation in steps S1 to S3 are all embedded in the attached table, so as to achieve a theoretical evaluation of the oxygen concentration in the area after the gas agent is released, and determine whether an actual oxygen concentration test is required based on the theoretically calculated oxygen concentration.

[0036] Step S4: if the calculated oxygen concentration is greater than 10% (vol%), there is no need to perform an actual oxygen concentration test.

[0037] Step S5, if the calculated oxygen concentration is ≤10% (vol%), an actual oxygen concentration test is required. If the actual oxygen concentration is ≤10% (vol%), the oxygen concentration test is performed again after implementing corresponding measures until the actual measured oxygen concentration is greater than 10% (vol%).

[0038] In the embodiment, the oxygen concentration test process is:

[0039] Prepare several oxygen probes and install them on the wall of the test room at a position of about 1.4-1.7 meters;

[0040] The release device in the area is activated and the drug begins to be released;

[0041] Observe and record the detection data of the oxygen probe, as well as the actual oxygen concentration during and after release.

[0042] In the embodiment, the corresponding measures include:

[0043] If the room volume is very small and the number of original gas cylinders is calculated to be ≤ 1 cylinder, then this room should be replaced with an independent gas fire extinguishing system, which includes but is not limited to gas cylinders, main pipes and zone valves;

[0044] If the room volume is large and the original calculated number of gas cylinders is greater than 1 cylinder, then reduce the number of released gas cylinders by one.

[0045] In the embodiment, for reducing the number of released gas cylinders:

[0046] Retest the room for oxygen concentration after the number has been reduced;

[0047] Determine whether the oxygen concentration after release is within the range of 10% ≤ O2% < 12%;

[0048] If yes, the oxygen concentration test ends;

[0049] If not, change the gas cylinder specifications and test the oxygen concentration again until the oxygen concentration meets 10% ≤ O2% < 12%.

[0050] The present invention adopts a method combining experiments with calculations to avoid design defects that may occur in the later stage during the design and construction process, and effectively reduces casualties caused by low oxygen concentration due to the release of gas fire extinguishing.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform, characterized in that: include: Step S1, calculating the required amount of medicine according to the net volume of the room; Step S2, selecting appropriate gas cylinder specifications according to the dosage of different rooms, and calculating the actual number of gas cylinders; Step S3, calculating the actual oxygen concentration in the room after release according to the actual number of gas cylinders; Step S4: if the calculated oxygen concentration is greater than 10%, there is no need to perform an actual oxygen concentration test; Step S5, if the calculated oxygen concentration is ≤10%, an actual oxygen concentration test is required. If the actual oxygen concentration is ≤10% vol%, the oxygen concentration test is performed again after implementing corresponding measures until the actual measured oxygen concentration is greater than 10%.

2. The method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform according to claim 1, characterized in that: In step S5, the oxygen concentration test process is as follows: Prepare several oxygen probes and install them on the wall of the test room at a position of about 1.4-1.7 meters; The release device in the area is activated and the drug begins to be released; Observe and record the detection data of the oxygen probe, as well as the actual oxygen concentration during and after release.

3. The method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform according to claim 1, characterized in that: In step S5, the corresponding measures include: If the room volume is very small and the original number of gas cylinders is calculated to be ≤ 1, then this room should be converted into an independent gas fire extinguishing system; If the room volume is large and the original calculated number of gas cylinders is greater than 1 cylinder, then reduce the number of released gas cylinders by one.

4. The method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform according to claim 3, characterized in that: In step S5, the gas fire extinguishing system includes but is not limited to gas cylinders, main pipes and zone valves.

5. The method for evaluating oxygen concentration after gas release at a gas fire extinguishing protection station on an offshore platform according to claim 3, characterized in that: In step S5, for reducing the number of released gas cylinders by one: Retest the room for oxygen concentration after the number has been reduced; Determine whether the oxygen concentration after release is within the range of 10% ≤ O2% < 12%; If yes, the oxygen concentration test ends; If not, change the gas cylinder specifications and test the oxygen concentration again until the oxygen concentration meets 10% ≤ O2% < 12%.

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