Storagetechis an Atex certified designer and manufacturer with extensive experience providing technologically advanced atmospheric storage tank and pipeline safety breather valves, vents and flame arrestors for oil, gas, biogas, petrochemical, chemical, pharmaceutical, agro, water, wastewater treatment,and utility industries
According to the academic resources, the operating principle of Flame Arrestor was founded in 1815, England at the Royal Institution of England. A committee of the English coal mining industry had needed for a protection method to prevent miners 'oil lamps from causing explosions when flammable gas called firedamp seeped into the mine shafts.
Flame and detonation arrester, although similar in construction, serve two very distinct purposes. Here answer some of the most common questions asked about flame and detonation arresters. A flame arrester is a safety device that is used on the pipeline or end of the line to block any fire or explosion passage through the line. There are mainly two types of flame arrester; detonation and deflagration. Detonation flame arrester is designed to overcome any sudden explosion impact in the pipeline, whereas deflagration is flame arrester is designed to block any fire flame in a particular location to stop fire to travel in the pipeline freely. Storagetech technical team is experienced to choose which type of flame arrester is required for a particular application. Even though there are many factors to choose, mainly location, product stored, and pipeline/piping design plays an important role.
Sometimes it is desirable to install flame arresters in the middle of a long pipeline. They are particularly suited for installation inside a tank house where vent pipes or lines are extended through the tank house roof or walls to the outside. Locating the unit inside eliminates difficult inspections on the storage tank roof and protects the vent from the freezing of condensate. Combustion in a pipeline can readily make the transition from deflagration than detonation; in the case of some designs, a detonation can be stopped, whereas a deflagration may pass through. Therefore, an in-line flame arrester must withstand and stop both types of combustion from both downstream and upstream in a pipeline. Since the pressures developed in the combustion can be high, the in-line arrester and pipeline must be properly designed, constructed and tested. The flame arrester element itself must be capable of withstanding substantial pressure differentials in both directions as a result of the combustion.
This type of flame arrester is installed on low-pressure storage processing tanks, bleed tanks, or other waste gas devices. Normally, they are installed on a vent nozzle mounted on a tank that is discharged directly into the atmosphere. They can also be incorporated as integral parts of conservation vents installed on atmospheric storage tanks containing flammable liquids. It should be noted that flame arresters are not always necessary as part of conservation vents. The gases produced by vaporization of many flammable liquids have similar flame speeds when mixed with air. Typical of these are gasoline, jet fuel, benzene, plastics monomers, and organic solvents. Often the pressure drop across the vent valve of a conservation vent is a ¾ inch (17mm) of water or more. In this case, the velocity of the gas flow through the vent-valve opening will be higher than the speed at which the flame can propagate upstream through the opening.
Deflagration Flame Arrestors
A flame arrester, designed to perform as an extinguishing barrier, which absorbs and dispels heat, reduces fire temperature and the oxygen level to stop the fire through layers of metal ribbons shaped with crimped corrugations. It is mountedeither vertically or horizontally (some cases) between two lines or used withthe pressure-vacuumvent on storage tanks.
Detonation Flame Arrestors
A flame arrester, intended to withstand higher pressures and continuous a flame than the deflagration flame arresters. Detonation Flame Arrester (also called flame arrestor or fire arrestor) is designed for installation in gas pipelines.
Detonation occurs when a flame travelling through the pipeline reaches supersonic velocities, usually as a result of the pipeline configuration or pipeline surface roughness. Changes in gas density and pressureproducethe flame velocity to metamorphose from subsonic to supersonic.
The flame quenching element is designed to be three or four times the area of the pipe in which it is installed, and is assembled between two flanged reducing spools. The element comprises a tightly rolled scroll or scrolls of crimped stainless steel ribbon to form passages through which the vapour passes. The area of each passage determinesthe levelof protection that the element provides. It has a maximum experimental safe gap (MESG) as per themodeland is suitable for gas groups IIB and IIA.
The detonation flame arrestor is more robust than the deflagration flame arrester, and contiguous scrolls have smaller MESGs to withstand higher pressures and to quench detonations. It should be installed in the pipeline where there is a significant distance between the unit and the potential source of ignition.
Storage Tank Pressure Relief Valve
A Storage Tank Pressure Vacuum Relief Valve is a safety device designed to protect storage tanks or pressure vessels by releasingpressure directly to the atmosphere. The Pressure vacuum vent protects the storage tanks against excessive pressure or vacuumgenerated in the tank. The vent performs as an inhaler under pressure or as a discharger of overpressure. When air pressure exceedsthe preset setting of pressure vacuum vent, the pallet opens, departs the seal, and expels any excessive negative or positive pressure.
They are commonly mounted to a flange or pipe, which connects thevaporspace of a storage tank. Dependent upon specific
requirements, the vents can be applied to desired specifications allowing the pallet assemblies to open when specific pressure and
vacuum levels are reached.
Emergency Relief Valve
An Emergency Pressure Relief Valve operates in the last resort when a vessel or storage tank is exposed to a large-scale fire, and the standard pressure relief valve has failed to open or cope with the extreme conditions.Designed to open in the event of high pressure, the set-pressure should be chosen to be above that of the pressure or pressure-vacuum relief valve. When the set pressure is reached, the vent cover rises sufficiently to dissipate the pressure in the tank. The weight-loaded emergency pressure relief vent is installed in the horizontal plane on a flange at the top of the tank. A secondaryuse of the unit is to access the tank for product sampling or depth gauging.
HOW TO TACKLE SAFETY AND ENVIRONMENTAL CHALLENGES OF STORAGE TANK OPERATORS
RECENT EXPLOSION TRAGEDIES have brought into focus the importance of engineering and building standards for storage tanks and industrial plants.
Conditions such as corrosion, age deterioration, natural disasters, lightning strike, and in some locations, seismic motions are the most common reasons for oil storage tank damage, and these causes may lead to small or large tank failures or accidents, with tragic consequences. Oil storage tanks can deteriorate in the course of time due to rust, fatigue or cracks. Tanks located near the seashore and saltwater are subjected to extreme environmental conditions and high levels of humidity, and loads of continuous charging and discharging add to the wear.
Damage can lead to the leakage of hazardous material, fire and environmental damage. The question is, how to tackle these safety and environmental risks? It may not be possible to abolish the safety risk completely, but it is possible to minimise it by using specially configured tank equipment. It is scientifically proven that storage tank equipment, in particular, flame arresters and storage tank valves, allows tank operators to minimise the risk in storage tank refineries where tanks contain hazardous, flammable, and explosive chemicals and petrochemicals
Fig.2. Recent incidents prove that specially configured devices such as the pressure/vacuum relief valve with flame arrester minimise the risk to almost zero in storage tank refineries.
Storagetech™ has taken the necessary action in terms of appropriate standards of designing, building and supplying storage tanks and tank equipment to protect tank operators, their assets and the environment. In September 2017 a rare lightning strike hit a storage tank in an above ground storage tank refinery in Columbia. A supervisor later discovered that the combination of a pressure/vacuum relief valve with flame arrester prevented a large accident by blocking the fire passage through the line through its flame arrestor device. “Using this combined technology prevents the ignition sources that may occur outside of the tank from interacting with the released gas during the breathing of the tank, and also blocks the transmission of deflagration flame and the passage of heat into the tank,” says Mahmut Tunaz, design engineer at ERGIL Turkey.
Multiple causes for safety and environmental challenges
Fig3.September 2017 – An Äager Brand Storagetech™ Flame Arrestor device saved the entire storage tank refinery of Grupsoil in Colombia.
Some conditions such as corrosion, age deterioration, natural disasters; lightning strike, and in some locations, seismic motions are the reasons of the most oil storage tank damages and these causes may lead to small or large tank failures or accidents along with tragic consequences as it was mentioned earlier. Oil storage tanks can deteriorate in the course of time due to rust, fatigue or cracks. Regard to these challenges, many tanksaresubjected to extreme environmental conditions because they are located near the seashore and a saltwater which lead to high-level humidity condition, and loads of continuous charging and discharging add to the wear.
Damage can lead to leakage of a hazardous material, disastrous fires and environmental damage. Thus, it can harm the environment along with the ecosystem. Many examples can be given based on this issue. But, the question is that how to tackle these safety and environmental risks? It may not be possible to abolish the safety risk %100 but it is possible to minimize it down to nearly ZERO. In this case, the combined device will take a significant role to protect your storage tanks and save your assets along with the environment. Some recent incidents prove that especially combined tank equipment (Pressure / Vacuum Relief Valve with Flame Arrester is shown above) minimizes the risk down to almost zero in storage tank refineries.
Technologically advanced solution for the protection of storage tanks and the environment
Äager brand Storagetech™ combination of the pressure/vacuum relief valve with flame arrester is a technologically advanced and environmentally friendly device and was developed with the dedication and extensive experience ofStoragetech™It provides protection, efficiency and emission control for storage tanks. The combination of pressure/vacuum relief valve and flame arrester can be categorised into different types. However, the pressure/vacuum relief valve with integrated end-of-line flame arrester is considered the most effective combination, ensuring ultimate protection against damage through overpressurisation and implosion due to vacuum conditions, and preventing any external flame entering the tank with its flame arrester winding system. In the closed position, the pressure relief pallet and diaphragm assembly are held tightly against a seal to prevent the loss of vapour to the atmosphere. The opening set-point is selectable from a range between 1 and 28.1 W.C. (2.5 and 70 bar), and the valve will reseal when the tank returns to a safe pressure.
Äager brand Storagetech™ pressure/vacuum relief valve with integrated flame arrester isATEXandISOapproved. Ensured performance for the combined device. It includes an optimised weather hood for severe weather conditions, and installation of electrical heating is available for standard design. This combined technology is maintenance friendly and provides no loss of vapour or explosion mitigation effect for routine inspection of the flame arrester. Ten per cent overpressure advanced technology reduces vapour emission to a minimum, and it also has very low leak rates to reduce explosion risk and ensure compliance with environmental requirements. This special combined technology will meet tank operators’ safety and environmental requirements when receiving periodic maintenance.As a result, it is favoured by many tank operators.
Fig.4. Combination of Flame Arrestor with Pressure Vacuum Relief Valve
Storagetech™ offers a wide range of flame arresters storage tank valves that includes end-of-line and the in-line flame unit for both deflagration and detonation service. These units prevent the risk of fire affecting the contents of storage tanks and pipelines.
The Company operates accredited management systems to guarantee its products are manufactured in accordance with international standards, and to maintain quality and materials traceability which leads to customer satisfaction and products that function safely. These includeISO 9001:2008– Quality management systems,ISO 14001:2004– Environmental management systems, andOHSAS 18001:2007– Manual for occupational health and safety system. Engineering standards in place includethe ASME U-Stamp Boiler and Pressure Vessel Certification, CE marking, andATEXcertification relating toDirective 94/9/EC– Equipment and protective systems intended for use in potentially explosive atmospheres.
Storagetech™ seeksto provide its customers with competitive pricing, outstanding performance, and environmental protection. Its manufacturing location has access to the biggest port in Turkey, railway, and good road facilities, making it ideal for serving worldwide.Storagetech™warehouse in Turkey provides convenience to its customers. These warehouses have ready stock in them. Customers can call in case there is a requirement.
Fig.5. ERGIL's packing system for keeping your products undamaged and safe before dispatch.