Responding to an oil spill

Oil is one of the most abundant pollutants in the oceans: about 3 million t of oil contaminates the oceans annually (source: www.marineinsight.com). The effects are not limited to the location of the spill; the shorelines and the terrestrial ecosystem may be affected as well. API Energy’s Oil Spill Prevention and Response guidelines give three primary objectives to deal with the resulting fallout: prevent the spill from reaching the shore, reduce the impact on marine life, and speed the degradation of any unrecovered oil. This article will cover three of the most important components to consider in oil spill response pattern.

Rule 1: Prevent

In an oil spill response strategy, prevention comes before the actual response and is based on a 'safety culture'. The core of it lays in the construction of the marine platforms: sound design, construction and operating practices, facility maintenance integrity, high levels of environmental awareness and staff training. At the design stage, measures are taken to mitigate possible spill scenarios and environmental risks: oil pumps are engineered to prevent leakage and equipped with shutdown device. They are also regularly tested. Metal design, cathodic protection, and corrosion inhibition chemicals are used for corrosion prevention.

Other spill prevention methods are spill collection facilities and blowout preventers. The first of these directs spills from processing equipment into settling tanks where oil can be recovered. Every well drilled is provided with stacked blowout preventers. Finally, to ensure that petroleum products are transported safely and responsibly, a ship vetting system is applied.

The implementation of technological innovations is indispensable in this part of the oil spill prevention strategy as the systems mentioned are tested and updated to ensure safety. Industry events are one way to keep up with these technological trends. At EPOCH 2019 participants have an opportunity to talk to the manufacturers directly and see demonstrations of equipment pieces.

Rule 2: Act quick

The success of the response depends a lot on the rapidness of the decision-making based on all the available data after an oil spill. The very first hours post-spill and before serious oil weathering are critical. The time in which an oil spill is reached also influences the choice of the cleanup methods. When it happens quickly, it is easiest to clean up by one of the following.

• Sorbents

They come in a lot of forms: long tubes (socks or ‘boom’), snare or pom-poms sheets, pads or sheets. A snare is a shredded polypropylene tied together and placed in sensitive areas affected by the spill to recover the oil. Sorbents consist of synthetic hydrophobic and oleophilic material and help to clean up the spills near a shoreline or the contained ones.

• Containment and skimming

In the first few hours, the best cleanup method is containment and skimming. The oil is skimmed from the surface, by the portable skimmers or boats. Containment booms are made of a foam-like material covered by a heavy gauge plastic. A weighted skirt that trails under the water is aimed to keep the oil from spreading out. The recovered oil is collected in tanks or vacuum trucks and hauled off-site.

One of the latest novelties in clean-up methods is a wood-based sponge developed by the Chinese Academy of Forestry. The sponge is reusable and biodegradable. The Academy removed the hemicellulose and lignin from cell walls in balsa wood to create a highly porous structure and freeze-dried the resulting material. A silylation process allowed them to grew a hydrophobic polymer within the pores of a freeze-dried sponge.

At the stage of response planning, it is useful to consider previous oil spill cases. It is better to meet specialists and receive experience and ideas face to face, but there are publicly accessible knowledge bases as well. For example, the International Association of Oil and Gas Producers (IOGP) founded the Global Industry Response Group (GIRG), which has identified recommendations related to both incident causation and response by such leaders of the industry as Shell, Total, Eni as well as 16 others.

Rule 3: Analyse

The decision-making process after an oil spill involves a wide range of issues and activities under emergency conditions and is based on: the characteristics of the oil spilt; changes in physical and chemical properties (weathering) and biodegradation; local environmental conditions; and effectiveness of response/clean-up technologies. To achieve better response capabilities, contingency planning and spill response are now integrated. Each oil spill is a tragedy - but also a chance to learn how to prepare better for future incidents.

Science and engineering data and information are used in a windows-of-opportunity technology to provide a scientific foundation for rapid decision-making in oil spill response strategies that optimise environmental and cost benefits. This is possible due to the selection of different oil spill response technologies. Smart software-based tools are assuming a role in contingency planning including management science and operational research tools. Emergency decision support systems (DSSs) for disaster responders can reduce losses due to environmental damage.

One of the recent remarkable projects in this direction is an interactive decision tree from the team of Southwest Research Institute engineers with the programming language Visual Basic for Applications in Microsoft Excel. It is designed to find the best solution for specific oil spill scenarios by helping to determine how dispersant technology will better perform under different conditions. Depending on the chosen environmental and oil data it comes with a necessary scenario from its database: the most efficient cleanup method and dispersant delivery approach.

To make a transition to such technologies or implement an automated element in your oil spill response strategy, it needs to be determined whether equipment, data collecting systems and management structure are ready for such updates. When choosing the technology provider it is important to consider the start-ups that sometimes may be even more advanced and flexible in developing the individual solution than the big market players.

Another rule: expect the unexpected

In 19 January 1991 the Persian Gulf spill occurred and the 4 in.-thick oil slick spread across an area the size of Hawaii. The spill was 260 million gallons. The lesson learned from this incident is clear - “We learned the lesson that we have to have an action plan – you have to expect the unexpected,” as Abdul Nabi Al-Ghadban of Kuwait Institute for Scientific Research said. “If you have an offshore operation, you need to have a good contingency plan in case of spillage, damage, earthquake, or a problem with the pipeline.”

By Regina Chislova, Project Director of EPOCH 2019. To learn more, visit https://bit.ly/2WLsoHy

Read the article online at: https://www.oilfieldtechnology.com/special-reports/24062019/responding-to-an-oil-spill/