Swiss Fire Protection Research and Development AG (SFPRD) offers a Pressurised Instant Foam (Pi Foam) fire protection system technology for full surface fires, on large diameter atmospheric storage tanks used in many industries. “Combustible fluids can cause fires in a wide range of sectors, from oil and gas, to pharmaceuticals, chemicals, foods, vegetable oils and the military. We have tested our system on a number of different combustible liquids. For instance, special dry foams are used for vegetable oil, to protect the product,” says SFPRD Director, Andras T. Peller.

Fires on oil storage tanks have attracted most attention. They have consumed millions of cubic metres of fuel, cost billions of dollars and hundreds of lives, with corporate costs of financial market impacts and brand impairment – and social costs of environmental damage.

The frequency of these incidents is increasing. Causes include natural disasters, operational errors, equipment failures, leaks and ruptures, floating roof sinks, static electricity, open flames, maintenance work, and sabotage – but lightning is the largest culprit, responsible for 33% of tank fires, according to SFPRD. As climate change increases extreme weather conditions, lightning strikes are becoming more common. For example, a 2014 study by David Romps, Earth Sciences Professor at the University of California, Berkeley, forecast a 50% increase in lightning strikes due to global warming. The intensity of storms and strikes is rising, with more hectic weather leading to more lightning strikes, sparking off many types of fires, including those in storage tanks. Fires can attack the tanks, and nearby areas such as dikes, pump stations, and auxiliary parts.

Fires can also be caused by sabotage, terrorism and hostilities. Recently in 2018, Libya’s Mitiga airport had a big fire, affecting four tanks, and costing USD 220 million. A militia rocket firing reportedly set one tank on fire.

SFPRD’s Pi Foam system can be split into two elements: the foam formula, and the fast and automated way in which it is applied to fires. SFPRD analysis suggests it is superior both in terms of the ingredients, and the modus operandi.

Costs

SFPRD has published a hypothetical comparative study of costs, including capital expenditure (capex) and operational expenditure (opex) for 20 tanks of 50 metres diameter each, assuming that a fire affects one tank alone (and various other simplifying assumptions). SFPRD estimates a 20-year cost of $3.3 million for Pi Foam, against costs twice as high for fixed systems, five times greater for semi-stable systems and six times more for mobile systems.

“Semi-stable units – a halfway house between mobile and fixed – may appear cheaper than fixed systems, in terms of lifetime costs and maintenance costs, but we doubt if they are when all costs of maintenance and opex are properly factored in over a 20-year period. Additionally, semi-stable systems could be a limited economy if they require mobile support in the event of a fire,” explains Peller.

Fixed systems have the highest up-front installation costs, due to the need for pumps, foam mixers, foam vessels, a water network, and a volumetric water reservoir. They can save on labour costs by operating almost automatically, but still need testing and maintenance of the equipment, with opex of perhaps $1.7 million over 20 years, SFPRD estimate.

SFPRD claims that Pi Foam’s fixed automatic system offers much lower lifetime costs, lower operating expenses, and lower maintenance and testing costs; some valve functionality tests and foam sample tests are needed, but SFPRD estimates that these cost only $30,000 a year. Costs are lower in part due to faster start-up and extinguishment, and because the system monitors its own pressure and sends signals. Absent an incident, or very high temperatures, the Pi Foam foams should last for 10 years.

The initial costs of the systems are similar, with most of Pi Foam’s savings coming from lower ongoing operational costs, in terms of not needing foam monitors, pumps, water supplies and specialised firefighters available around the clock. These labour costs are highest for mobile systems, which are not cost effective, according to SFPRD’s methodology. SFPRD defines “breakeven” by comparing the costs of fire protection systems, with the probabilistic costs of a fire: costs multiplied by statistical probability. SFPRD estimate payback periods of seven years for the capex and opex on Pi Foam, against 15 years for some traditional systems. The conclusion is that mobile, semi-stable and fixed systems will take longer to break even or may not do even after 20 years.

Efficacy

Yet a purely financial calculus ignores the public relations disaster of a fire, and human costs, which mean defeating fires is an over-riding goal for some companies. SFPRD argue that many traditional firefighting systems cannot rise to the challenge of the largest tank surface fires.“Mobile fire units are not fast enough. Though there are a wide range of scenarios, even the fastest fire brigades cannot start extinguishing for 20-30 minutes, due to travel and set up time, which can leave a tank 100% damaged. Stable systems, usually involving pumps, spring into action much faster, but may not offer sufficient foam intensity,” explains Peller.

“Many basic protection systems cannot handle fires larger than 40 metres in size. Mobile, semi-stable or fixed systems may be adequate for rim seal fires, but not full surface fires,” says Peller.

“Pi Foam is also more versatile than semi-stable extinguishment methods, being able to use a wider variety of foam devices, for example circular injection rings, foam pourers, foam monitors, hand monitors, foam sprinklers and bar open pipe ends,” he adds.

Pi Foam’s third generation system needs no water network, no electricity, no diesel pumps, and normally no human intervention, though it can be manually operated, as it is at OMV’s Yemen facility. Some human input is needed after a fire, to clean the system, reset the fire sensors, refill, and re-pressurise them. Any system is only as strong as its weakest link, and any number of factors –water shortages, electricity failure, pump failure, or human error can be sources of capacity limits, error and failure for other systems.

Pi Foam is automated through three separate alarm systems, two of which need to be set-off independently to start the extinguishment process. False alarms are very rare.

Greener foams

Any type of foam could be used with Pi-Foam’s pressurised gas system, but environmental concerns mean some firms are already prohibited while others will be avoided by companies with a strong commitment to environmentally friendly policies. “Fluorinated hydrocarbon foams are effective at extinguishing fires, but are also highly toxic, carcinogenic, and are not biodegradable,” says Peller. They can contaminate surface water, ground water, fish and fish eggs, soil and cause other damage from toxic foam spillage and fumes. PFOS foam was added to Annex B of the Stockholm Convention on Persistent Organic Pollutants in May 2009. “Flourinated foams have been used since the 1950s, but some longer chain ones are already prohibited, while C6 forms (with a chain length of C6 or less) still in use are also toxic,” says Peller.

Therefore, various fluorine-free foams have been developed, including Pi Foam, which is “completely fluorine-free, non-toxic, and non PBT (non-Persistent, non-Bioaccumulative and non-Toxic). SFPRD-LL bio foam does not damage tanks, cause air pollution, foam spillage or soil contamination. A toxicity check was carried out by a government agency when the technology was being developed,” explains Peller.

Faster and more powerful foam

Pi Foam is also more efficient. “It is a breakthrough in being water-soluble. Traditional foams have mixed foam solution with air, which requires a lot of energy, and sophisticated, high maintenance stations to maintain pressure. Pi-Foam is a self-expanding foam, stored under pressure, and pressurised with a gas that is water-soluble, like soda. The whole pre-mix solution is released through the force of the pressure. Small bubbles in the liquid generate the foam itself, when released from the pressure vessel,” says Peller.

“Fires need to be extinguished with foam that is lighter in weight than hydrocarbons, so that the foam stays on the surface of the liquid and insulates it with a blanket of oxygen on the surface, to separate the fire from the liquid. It is vital to separate the liquid surface from the fire, otherwise the fire can eat up the foam, which creates a battle between the foam introduction rate and the fire,” explains Peller. The techniques used to apply the foam are also important: a patented circular injection ring applies the foam from the perimeter of the tank with constant and high velocity.

Consequently, foam intensities are much higher. “Traditional systems achieve 4-8 litres per square metre per minute, while Pi Foam can do 60-80. This generates ten times as much foam per square metre of storage tank surface, and very quickly extinguishes the fire,” says Peller. Foam intensities need to be much higher for large surface fires, covering above 40 metres in diameter.

Time is of the essence

Pi Foam has earned its name by extinguishing fires in less than minutes, according to SFPRD. Other fire suppressing systems have taken hours – or even days. “Pi Foam’s speed is crucial because after five minutes, and at around 500 degrees Celsius, the wall of the storage tank can suffer irreversible damage and has to be rebuilt. With Pi Foam, the storage tank can be emptied, cleaned and refitted,” says Peller. “All of this makes the system very simple, effective, scalable and cheap,” he adds.

Patented technology

The inventor is Hungarian, Dr Istvan Szocs. The intellectual property behind Pi Foam is a trade secret, but Peller can reveal that a surfactant generates the foam – and that it is edible but would not taste too good! The IP is not only about ingredients but also about methods. The original patent (for Foam Fatale) applied in around 30 countries, and the new patents are, starting in 2017, being rolled out, country by country, including in the US, Canada, Mexico, Gulf states, Europe, Russia, India, China and South Africa. Peller believes that the technology is quite unique.

EU and US standards

Pi Foam’s certification status is somewhat nuanced. Strictly speaking “it cannot attain the EU environmental safety standard on foam systems for fire protection (EN 13565-2) because not all aspects of that standard are applicable. For instance, Pi Foam does not have any pump stations. However, Pi Foam meets those elements of the standard that are applicable, and offers equivalent or better solutions for others, according to independent certification and product testing body, TUV Süd of Germany,” explains Peller.

Pi-Foam is working towards the US NFPA standards, which are best practice recommendations created by the National Fire Protection Association (NFPA), which is not a government body. However, the practical relevance of these standards for SFPRD’s particular niche in the firefighting space is open to question. Existing standards may prove woefully inadequate for large full surface fires anyway. For instance, the NFPA 11 only requires 4 litres per minute per metre square, which is over 90% less than Pi Foam’s capability, and insufficient for large surface fires.

Case studies

Pi Foam has case studies for each generation of its system. Companies already using older versions of Pi Foam include Chevron, Wintershall, Sanofi, OMV and MOL of Hungary. Chevron is installing a system with the capacity of simultaneously extinguish a 11,500 sqm fire surface (equivalent of a 122-metre diameter tank), which will be the largest capacity fixed firefighting system in the world.

The first-generation firefighting system has been deployed in the Habban Early Production Facility, Yemen Block S2 Oilfield, operated by Austrian energy company, OMV. Pi Foam built a fast reacting system that provides instant foam fire protection for a facility producing 3,500 cubic metres per day, stored and processed in four process tanks and four storage tanks with capacity of 127 metres cubed each.

The second-generation firefighting system is pending construction in Chevron’s Saudi Arabian facility at the Mina Saud tank farm in Kuwait.

Oiltanking Hungary is planning to upgrade its firefighting installation in Budapest, to meet higher safety levels in their tank farm. It has been using the first-generation system since 2001 in a small part of the facility, so they were considering the extension with the newest generation to the whole park.

Tenders sought for licensing

SFPRD’s business model is to license technology to partners in what would probably be a royalty deal. “The inventor is a great engineer but not a businessman, so he approached us to raise awareness of the technology. We formed a joint venture in 2014 to develop and commercialise the technology. We set up SFPRD, and hired engineers, chemists, and fire protection engineers to develop the technology further into third and fourth generation versions based on the same basic principle, but more efficient and cheaper for different environments. Now the development phase has finished, we are ready for the market and are inviting tenders,” says Peller.

“This technology can change the whole landscape of fire-fighting and save billions around the world,” sums up Peller.