Tank Storage Magazine v08 i04


Volume: 8
Issue: 4
Date Published: August 31, 2012



NuStar: on a roll

In a difficult market one might expect storage operators to be reporting lower earnings, especially compared to the booming conditions of just a few months ago. Not so for San Antoniobased terminal operator NuStar Energy, which certainly seems to be bucking this trend. The company announced increased first quarter earnings of $96.8 million (€75 million) compared to $92.9 million for the first quarter of 2011. Much of this can be attributed to its recent success story in Louisiana. In February this year NuStar announced it would be investing $365 million at its St James Terminal to add 3 million barrels of capacity over the next two years, taking the total storage at the site to over 11 million barrels. The first 1.5 million barrels is expected to come online in early 2013. The facility has 30 tanks in service ranging in size from 180,000 barrels to 600,000 barrels and will be adding four more during the expansion phase.

Canada's oil output to double by 2030

Production figures emanating from Canada’s oil patch suggests an insatiable spending spree. Crude oil production will more than double to 6.2 million barrels per day by 2030 from 3 million barrels per day in 2011, according to the 2012 forecast from the Canadian Association of Petroleum Producers (CAPP) in Calgary. ‘Resurging growth in Western Canadian conventional oil production and new oil sands investments are driving the positive outlook,’ says Greg Stringham, CAPP’s VP of markets and oil sands. ‘Canadian oil is clearly on the global stage and this forecast growth will put Canada in the top three or four oil producers in the world.’ Conventional production is increasing because new technology allows industry to produce oil from formerly uneconomic resources, reversing a significant declining production trend over the last decade. Oil sands growth reflects Canada’s supply potential and growing international demand for oil. The growing oil supply is aimed at markets in eastern Canada, which currently imports more than half its oil from offshore foreign suppliers, traditional and new markets in the US (displacing imports from less secure foreign sources) and growing markets in Asia.

Evaluating and learning from near-misses

One finding common to most investigations of major failures is that they are preceded by a series of smaller incidents or near misses, which, for a variety of reasons, not the least of which is dumb luck, do not result in a high consequence event. These precursor incidents are opportunities to investigate and discover the organisational causes and correct these to prevent major incidents. A common key root cause finding in most major failures or accidents is a lack of an effective reporting and investigation system for incidents. A look back at a few high profile failures and the investigation results reveals this common theme. The investigation of the Buncefield oil storage depot explosion and fire on 11 December 2005 showed there were a number of incidents prior to the major failure. The immediate cause of the explosion and fire was the failure of both an independent high level switch (IHLS) and the automatic tank gauging system (ATG). The servogauge on the ATG had stuck which caused the level gauge to ‘flatline’ and therefore not indicate the rising level in the tank. The ATG servogauge had stuck 14 times in the three months prior to this major failure. The root cause of the ’sticking’ was never properly investigated or determined.

Combining accuracy with safety

A storage tank overfill can occur during product delivery or due to internal pressure build-up. Both recurring small product spills and sole large overfills can result in severe safety, environmental, monetary and violation consequences. Phillips 66, a global leader in the refining, marketing and transporting of crude oil and petroleum products, has a storage terminal located in Pasadena, Texas. With 22 aboveground storage tanks and four sump tanks, the Phillips 66 in Pasadena has its product (petrol, kerosene and diesel) transferred through pipeline to be stored at its facility. For Phillips 66, having reliable level gauging technology with overfill protection is not only vital, but essential for its day-to-day operations. US-based level gauging and overfill alarms specialist L&J Engineering helps facilities stay in compliance with industry regulations and recommendations. To ensure its facility conformed to overfill regulations, Phillips 66 installed L&J Engineering’s MCG 1090 High Level Alarm Probe and MCG 7000 Alarm Monitor independent overfill protection system.

Mitigating corrosion

Storage tanks can take a beating from corrosion over time. The vapour spaces in cone roof tanks and some floating roof configurations are left to the mercy of the product that they contain. There are limited options generally available to protect these expensive roofs, such as: coatings, alternative metals such as aluminum or stainless steel, and active gas blankets. For cone roofs, coatings are the most common corrosion protection method, but are often the least effective as there are many steel surfaces that are all but impossible to effectively cover. A roof which is susceptible to underside corrosion from the vapour space environment is likely to have one or more of the following issues: • A shorter service life • May result in an environmental or safety hazard • May have product contamination from corrosion products and/or rainwater • Unscheduled downtime and unplanned maintenance costs.

Maintaining â

The uncontrolled and unplanned release of toxic crude into the environment is every oil operating and handling company’s nightmare; it will most certainly damage the surrounding environment, sometimes beyond repair. This was the case of the catastrophic Gulf of Mexico Deepwater Horizon oil spill incident in April 2010. Approximately 790km of US coastline was contaminated by the oil leak from the underwater oil well and BP is currently executing an extensive restoration project that, to date, has cost BP around $14.7 billion (€12 billion). Oil spills will also impact the company’s reputation as a reliable provider and most definitely reduce its profits. No oil operating company is immune to this potential hazard, as was the case with Kuwait Oil Company (KOC) when, in July 2009, crude oil supply was abruptly stopped to Al-Zour power station for a few hours, due to a largescale, uncontrolled oil leak in the pipeline feeding the power station. Another incident occurred in KOC’s South Tank Farm (STF) in November 2007, where the filling operation to three tanks was stopped for the same reason.

Avoiding pitfalls with floating roof seals

With numerous seal options available and limited guidance from existing standards, selecting and configuring the right floating roof seal can be a difficult task. It is one that, when done incorrectly, can lead to problems ranging from regulatory compliance issues to premature maintenance outages to more significant failures. In addition, as new employees enter the work force and experienced employees retire, it is important to have an internal list of guidelines aside from the standards that will ensure asset longevity and optimal operational efficiencies for tanks. Most tank owners are familiar with current resources such as API 650, Appendix H & C; EPA Air Rules; EPA AP- 42; API MPMS, Chapter 19; API RP 545; NFPA 11; as well as a few international resources such as EEMUA 159, BS EN 14015:2004 and the European Parliament and Council Directive 94/63/EC 1994. Though these existing guidelines provide some specifics such as types of seals required by regulation, shoe dimensions relative to liquid and in some areas, materials requirements, a lot is left open to interpretation. There are numerous crucial purposes for floating roof seals including: emissions mitigation, centring the floating roof to allow safe operation, dampening floating roof movement and protection against rim fires. Whether building new tanks or taking a tank out of service for regular inspection and maintenance, effective planning with accurate data resources is key to ensuring the floating roof seal accomplishes

Dulux improves storage inventory management

Dulux (Pty) in South Africa is a wholly owned subsidiary of AECI, one of the leading industrial paint and coating groups in southern Africa. As part of a strategy to improve plant efficiency, the company decided to engage the services of automation solutions provider Omniflex, which has offices in South Africa, Australia and the UK. The company needed to provide direct control to vendors in the management of bulk chemical supply and on-site storage. Dulux required the monitored information to be made available to vendors so they could monitor at any point in time and from any location.

Down but not out

As assets approach the end of their lifecycle, critical decisions must be made on their decommissioning and reuse. The primary challenge is finding an appropriate balance between engineering feasibility, environmental protection, public health, worker safety, risk and budget. It is important to consider the ‘what ifs’ and potential scenarios that could affect the project – everything from neighbouring property activities, traffic patterns and weather to permits, regulators, waste identification and disposal. The first step in preplanning is understanding the site. What were its historical uses? Who are and were the neighbours? If the site has been dormant for a long period, are there any employees still available to interview? Are there aerial photos? What about permit records? Where are the underground utilities located? Are they live? Can utilities be safely de-energised without disruption to others’ services? Much of this information may not be readily available and additional effort and time will be needed to research and collect this valuable intelligence. Next, it is important to think about the project schedule and budget, as these items will affect other pre-planning and strategy decisions. When does the site need to be decommissioned? Six months, one year, three years? Is the site owner leasing the property or are there third party entities involved, such as port authorities? Who is responsible for the decommissioning costs? Is there an estimated budget?

The not so sweet smell of success

Analysis of any particular medium is designed as a method of control. Whether it is the regulation of pharmaceutical products, foodstuffs or any type of fuel, the test scope will be specifically tailored to determine the essential requirements of the individual product. In the majority of cases the analysis will focus on the physical parameters which determine the suitability of the product for use. However, the analysis takes on a far greater significance when the focus falls on the aspect of health and safety. The evolution of the ISO 8217 test standard has been a continuing project since it came into being in 1987. The original standard examined the overall quality of the product to be supplied with the flash point of the fuel being the only parameter that was directly linked to the safety of the onboard crew. However, the use of residual marine fuels brought about another risk not documented in the original ISO 8217 standard. 

Removing the risk of uncertainty

Newly developed technology for tank gauging can help bulk liquid storage terminals handle the ever-increasing demands on efficiency, safety and accuracy. An open system architecture makes it easy to install the devices needed today and add or replace units in the future. This flexibility protects users’ investments so that refineries and tank farms can become and stay efficient. Additional benefits include lower installation costs, high accuracy and built-in safety functions. One feature with substantial potential to save cost is wireless transmission of measurement values. This enables high precision tank gauging data to be made available anywhere on the plant at a much smaller cost than before. A modern automatic tank gauging (ATG) system is an integrated high performance measuring and calculation system. It normally includes sensors for measurement of the following storage tank data: • Level • Average product temperature • Pressure (if on-line density and mass is required) • Free water level (if required).


With the growing popularity of ground improvement (GI), tank designers no longer need to let the ground conditions dictate the capacity of the tank. GI methods do just what their name implies; improve poor ground conditions in many ways using in situ construction methods that reinforce, change or densify existing ground conditions. Tanks are not unique structures, but the loads they apply to the ground offer some unique challenges to the foundation designers and contractors.Tanks are typically large structures with diameters sometimes exceeding 300ft and heights exceeding 60ft. This combination of tank diameter and height can result in the soil beneath the tank being stressed to depths that are often not explored with typically limited investigations. A 300ft diameter tank when filled to its capacity can affect significant changes in the stress level in the soil to depths exceeding 300ft, so it is always prudent to perform a soil investigation to a depth of at least one tank diameter. Sometimes rock or some other feature found at depth will limit the depth explored. Tanks placed within one half diameter of one another will also create zones of influence that magnify the stress levels in the soil beneath the tanks.

Making life easier

Many terminals built decades ago no longer fulfil the flexibility needs of today’s operations in terms of product handling, speed of operations and modern technology. In most cases the only option for a re-design is a complete re-build. This is not only costly, it would also require customers to find other storage capacity during the period of downtime. Oiltanking Copenhagen (OTC) is a typical terminal situated in Denmark, built in stages from 1960-1972. OTC has a storage capacity of nearly 390,000m3 in tanks sized from 1,000m3 up to 16,500m3. The customers include Scandinavia and Baltic regional operators. OTC handles products like A1 jet fuel, diesel, petrol and VGO. The heart of the OTC terminal, the manifold system, is a DN250 piping system for pumping and DN300 for suction. The valves used on the manifold are gate valves and to make sure nothing comes downstream when the gate valve is in closed position, OTC uses blinds as well. Blinds are needed since the gate valves are not 100% tight and there is no possibility for verification that the valves are sealing as required. Using the blinds avoids any unintended mixing and unneeded waste of product.

TEEX announces revision to fire fighting training

One of the worst case scenarios emergency responders face each year is incidents involving fires at flammable liquid storage facilities. According to the National Petrochemical and Refiners Association (NPRA), there are 16.8 million barrels of product refined in the US each day from 149 operable refineries. It is clear there is a need to have responders trained and prepared to respond to emergencies which result from flammable liquid fires. As one of the primary providers of emergency response training in the world, the Texas Engineering Extension Service (TEEX) – Emergency Services Training Institute (ESTI) www.teex.org/fire should be in a position to assist emergency response organisations in training their members in the safe response to liquid storage facility fires. To meet this need, modifications to Training Project #45 – API Storage Tank were needed. Project #45 – API Storage Tank Training prop in its current configuration is used to deliver flammable liquid firefighting tactics to fire fighters including paid, volunteer and private industry fire fighters. The training prop configuration offers class participants familiarisation with spill fires and a single tank training prop which can be used for foam applications to the seal and full surface fires. The training prop has full height sides, thus making it impossible for class participants to observe any of the foam application, fire chemistry and flammable liquid surface responses discussed during classroom sessions.


Following two decades of civil war, Liberia has slowly been rebuilding its economy. As an example of this, state-owned Liberia Petroleum Refining Company’s (LPRC) fuel storage terminal near the country’s capital at Monrovia is being updated. The facility had fallen significantly behind international standards during the war-torn years between 1989 and 2003. The terminal is now ongoing an entire refurbishment programme – from modernising the boat offloading, pipeline and jetties at the site, to carrying out all of the civil engineering at the tank farm, demolishing the redundant plant, constructing new bunding, laying foundations, constructing new tanks, laying pipelines, installing new pumps and electrical systems, developing new instrumentation and even installing new fire fighting systems.

Sometimes simple really is better

A lightning strike consists of two components: a short duration, high-energy spike, followed by a longer duration, lower energy tail. While the high-energy spike is truly impressive, it is the lower energy, long duration component that is actually responsible for ignitions in tanks. The roof of the tank floats on pontoons on the stored product. It is centred in the tank shell by centring shoes. Vapour is contained by a primary and a secondary seal. These tanks have traditionally been equipped with flexible, stainless steel grounding shunts extending over the secondary seal and spaced at frequent intervals (10” maximum) around the perimeter of the floating roof. Additionally, the floating roof is usually bonded to the tank shell with one grounding conductor run along the stairway from the top of the tank shell to the floating roof. Lightning becomes an issue when it strikes either the floating roof, the tank shell, or nearby. Ignition is not normally caused by the heat of the lightning channel igniting venting vapours; it is caused by arcing from the secondary effect of lightning. A thunderstorm is an electrically charged cloud mass, with a charge, usually negative, at its base. That charge induces an opposite charge, usually positive, on the surface of the earth beneath it. When lightning attaches to a tank or other object on the surface of the earth, the charge at the point of attachment changes dramatically and almost instantly. The surrounding ground charge rushes toward the point of the strike. If that in-rush of charge crosses a gap, it may arc. If that gap is between the floating roof and the side of the tank shell, and there are flammable vapours present, those vapours may ignite.


Storage tank corrosion inspection is an essential part of asset management, being used not only to certify safe operation, but also to predict expected lifetime, devise a repair strategy and assess the impact of different contents stored. In specifying the inspection to be performed, and in assessing the quality of the final report, it is important that engineers understand the key measurements made in terms of accuracy and reliability. It is an old adage for any system that ‘rubbish in equals rubbish out’, and this applies equally to tank inspection. API 653 and other standards are well established to determine tank condition, using input data collected from inspection equipment, operated by inspection personnel. If the key data is of poor quality, then the assessment is also likely to be of poor quality.

Upgrading to face a diverse future

For the past year the Martigues-based oil ports of Lavera and Fos, which are a short drive away from Marseille in the south of France, have been operated by newly formed company Fluxel. Born out of the French Harbour Reforms implemented in 2008, Fluxel has hosted more than 3,200 vessels and turned over €32 million over the past 12 months since the Marseille Port Authority assigned Lavera and Fos under its stewardship. And Fluxel has recently updated its maintenance systems through a partnership with maintenance management software solutions provider Carl Software as, although the port has seen a drop in visiting workload, it wants to streamline its processes to make sure it is ready to handle any future increase.

Small is beautiful

Robert Bryce, a US energy expert and journalist, opened the ILTA in Houston by giving an overview of the energy sector over the last decade. He spoke about what he sees as the fundamental flaw in US energy policy, especially when it comes to public opinion on green energy. Green energy, such as solar, wind and biofuels is favoured over more traditional sources such as coal, natural gas and oil, but, he said, it is all just hype. ‘These types of energy cannot provide the scale that the world demands,’ he said. ‘Shale, on the other hand, which is changing the US’ outlook when it comes to domestic energy production, can – but it is facing huge opposition.’