POZHNEFTEHIM ON DESIGN OF WATER SPRAYING INSTALLATIONS WITH DELUGE SPRINKLERS ORK AND NRO

From May 31 to June 3, 2023, the XXXV International Scientific and Practical Conference "Actual problems of Fire Safety" was held within the framework of the salon "Integrated Safety" of the Ministry of Emergency Situations of Russia. At it, the head of R&D of Pozhneftehim, Candidate of Technical Sciences, Yuriy Poteryaev, presented a report on the Current issues of water spraying installations' design at oil, oil and gas and petrochemical industry facilities.

The expert spoke about the use of the new generation deluge sprinklers NRO and ORK produced by Pozhneftehim as part of modern fire extinguishing and / or water spraying facilities with flammable and combustible liquids, LPG and LNG. These products were developed within the framework of the import substitution strategy of Pozhneftehim Group.

Water irrigation of tanks, apparatuses and equipment with flammable liquids and gases, pipelines and load-bearing metal structures is extremely important for fire protection of oil and gas facilities. Thanks to water irrigation and cooling of structures, rapid localization and elimination of fires by foam fire extinguishing systems at facilities is possible.

Water irrigation installations perform several important functions.

Firstly, it is the preservation of the strength characteristics of metal structures. Without cooling in fire conditions, irreversible deformations, loss of bearing capacity and collapse may occur. In addition, excessive temperatures can cause the destruction of devices and equipment under pressure.

Secondly, these installations are necessary for the non-proliferation of fire to neighboring fire-hazardous objects, especially tanks with storage of flammable and combustible liquids. Water cooling removes heat radiation of fire on a nearby object from metal structures.

In addition, water irrigation increases the efficiency of foam fire extinguishing installations. So, the side temperature of the tank RVS-20000 with oil product during 180 seconds of free burning exceeds 1000 ° C. At the same time, the temperature of the oil product does not exceed the boiling point and can be in the range of 100-150 ° C. When foam is applied, free burning of the oil product stops relatively fast in areas of combustion where there are no metal structures. In areas of contact of foam with heated metal structures, the latter, due to high temperature and heat capacity, destroy the foam, intensively evaporate the oil product and create a zone of stable burning. This effect is observed during tests according to GOST R 50588-2012 (see photo).

A fragment of the test according to GOST R 50588-2012. The foam is swollen around the perimeter of the pan and flames are making their way through it.

The requirements for water irrigation installations are contained in a number of regulatory documents – national standards and codes of rules of the Russian Federation:

• GOST R 12.3.047-2012 "System of labour safety standards. Fire safety of technological processes. General requirements. Control methods";
• GOST R 59580-2021 "Water irrigation of technological equipment and structures. Fire safety requirements";
• SP 92.13330.2012 "Warehouses of dry mineral fertilizers and chemical plant protection products";
• SP 155.13130.2014 "Warehouses of oil and petroleum products. Fire safety requirements";
• SP 162.1330610.2014 "Safety requirements for the production, storage, transportation and use of liquid hydrogen";
• SP 240.1311500.2015 "Storage of liquefied natural gas. Fire safety requirements";
• SP 326.1311500.2017 "Objects of low-tonnage production and consumption of liquefied gas. Fire safety requirements".

The above documents contain general design requirements for water irrigation installations, such as response time, intensity and duration of irrigation. However, there are no methods for designing, selecting and placing sprinklers at the facilities of the oil, oil and gas and petrochemical industries, such as:

• vertical and horizontal steel tanks;
• spherical pressure tanks for compressed and liquefied gases and liquids under pressure;
• column devices;
• isothermal tanks for liquefied natural gas;
• technological equipment;
• piping devices;
• conveyor belts;
• transformers and much more.

Pozhneftehim, a specialized company in the field of fire protection of industrial facilities, conducted its own R&D in order to develop effective and convenient in the design of ORK and NRO deluge sprinklers for the main fire-hazardous industrial facilities. In 2023, the certification of these products for compliance with the requirements of the TR EAEU 043/2017 – the Technical Regulations of the Eurasian Economic Union "On requirements for fire Safety and Fire Extinguishing Means" was completed.

SPECIAL PURPOSE DRENCHER SPRINKLER ORK

FSIP patent No. 199388 dated 31.08.2020, GOST R 51043-2002,

TU 28.99.39-054-72410778-2020,

TR EAEU 043/2017 No.EAEU RU C-RU.CHS13.V.00427/22

ORK sprinklers are designed for water irrigation (cooling) installations of vertical steel tanks and column apparatuses.

UNIFORM IRRIGATION NOZZLE (NRO), SPECIAL PURPOSE DRENCHER SPRINKLER

TU 28.99.39-062-72410778-2022,

TR EAEU 043/2017 No. EAEU RU C-RU.CHS13.V.00714/23

NRO sprinklers are designed for water irrigation (cooling) installations of spherical and horizontal steel tanks, as well as various technological equipment and structures.

The special purpose deluge sprinklers ORK and NRO are an effective and reasonable solution in terms of the selection, design, manufacture, supply and operation complexity. Distinctive characteristics of ORK and NRO:

• guaranteed length of the fan and the jet feed torch, regardless of the direction of the feed;
• the possibility of applying any K value from the specified ranges;
• a wide range of values of the angles of the torch or fan, depending on the design needs, etc.

To help technical specialists, Pozhneftehim has developed a methodology for calculating and selecting parameters that ensures maximum compliance with the required estimated and actual water consumption to save money on the purchase of pumping units, pipelines and other equipment.

Research data indicate that for effective removal and reflection of up to 95% of thermal energy, it is necessary to create a uniform water film with a thickness of 1 mm. Therefore, the uniformity of irrigation is important. Tests (see 1 below) were carried out abroad: a container with LPG was exposed to propane jet combustion from 20 nozzles. In the experiments, either irrigation from above or uniform irrigation over the entire area was provided. In the first case, the walls warmed up to 400 ° C in a few minutes. In the second case, the temperature did not exceed 110 °C for 90 minutes. At the same time, the intensity of uniform irrigation was 2.5 times less than in irrigation only from above.

The advantage of the NRO uniform irrigation nozzles produced by Pozhneftehim over other high-speed sprinklers is that the uniformity of irrigation is guaranteed in any spatial position (not only from top to bottom), the preservation of the spray angle and the length of the plot, as well as the direction of irrigation in the wind, while observing the distance from the sprinkler to the irrigated surface 1-1.5 m (less than 3 m).

The ORK deluge sprinkler for tanks and column apparatuses, like the NRO, has a guaranteed shape and length of the jet in conditions of wind loads. At the same time, the main technical parameters (operating pressure, productivity, spray angle, angle of inclination of the relative horizon with a vertical arrangement of the sprinkler) can be set by the customer from the range specified by the manufacturer.

Water spraying system for the spherical tank with NRO deluge sprinklers, nozzles for uniform irrigation, produced by Pozhneftehim (irrigation map, side view)	Water spraying system of the column apparatus using deluge sprinklers ORK produced by Pozhneftehim (irrigation map, top view)

When designing a water spraying installation, sprinklers with the required spray angle are placed on a three-dimensional model based on the irrigation conditions of all metal elements. Further, taking into account the intensity norms, the required productivity coefficient from the proposed range is calculated for each sprinkler.

Deluge sprinklers ORK and NRO with flexible technical characteristics are necessary for spherical, horizontal or isothermal tanks, process equipment and pipeline overpasses, where the choice of parameters of sprinklers is determined by the geometric characteristics and design features of the protected objects. The figures below schematically show examples of the location of nozzles for these objects.

The issue of the effectiveness of water cooling in the context of fire protection of industrial facilities with storage and handling of flammable and combustible liquids, LPG and LNG deserves the attention of experts and design organizations. Therefore, Pozhneftehim is currently preparing a standard of the organization STO, which will be useful for solving practical issues in the field of design and calculation of the main parameters of water irrigation installations.

Earlier, Pozhneftehim developed and registered with the EMERCOM of Russia the Standard of the organization VNPB 128-22, STO 100511503-UPS-VA "HELIPORTS. Stationary automatic fire extinguishing installations. Norms and rules of design", which allows you to specify the norms and rules for the design of fire extinguishing systems with means supplying fire extinguishing substance produced by Pozhneftehim.

¹ B. Droste and W. Schoen. Investigations of water spraying systems for LPG storage tanks by full scale fire tests Journal of hazardous materials, Volume 20, December 1988, Pages 73-82 https://doi.org/10.1016/0304-3894(88)87007-9