In-situ burning with chemical herders for Arctic oil spill response: Meta-analysis and review

Environmental hazard and preliminary risk assessment of herding agents used in next generation oil spill response

Herding agents offer a significant advance in oil spill response by overcoming past barriers limiting effectiveness of in-situ burning. This paper reviews the use, environmental fate and effects of two commercial herders, Siltech OP-40 and ThickSlick 6535. A conceptual model is proposed to describe herder fate followed by a screening exposure analysis. Hazard concentrations intended to protect aquatic life are derived using empirical toxicity data, interspecies correlation estimation and group target site models. Using exposure and hazard evaluations, a preliminary risk assessment is performed demonstrating acceptable risk to aquatic life. Hazards posed to wildlife are also reviewed. Potential harm to wildlife can be avoided or minimized by adopting best management application practices. This synthesis is intended to provide a valuable resource describing the rationale for herder use, evaluating environmental risk trade-offs and informing future oil spill response planning and decision-making. Priorities for further research are identified.

Modeling study on oil spill transport in the Great Lakes: The unignorable impact of ice cover

The rise in oil trade and transportation has led to a continuous increase in the risk of oil spills, posing a serious worldwide concern. However, there is a lack of numerical models for predicting oil spill transport in freshwater, especially under icy conditions. To tackle this challenge, we developed a prediction system for oil with ice modeling by coupling the General NOAA Operational Modeling Environment (GNOME) model with the Great Lakes Operational Forecast System (GLOFS) model. Taking Lake Erie as a pilot study, we used observed drifter data to evaluate the performance of the coupled model. Additionally, we developed six hypothetical oil spill cases in Lake Erie, considering both with and without ice conditions during the freezing, stable, and melting seasons spanning from 2018 to 2022, to investigate the impacts of ice cover on oil spill processes. The results showed the effective performance of the coupled model system in capturing the movements of a deployed drifter. Through ensemble simulations, it was observed that the stable season with high-concentration ice had the most significant impact on limiting oil transport compared to the freezing and melting seasons, resulting in an oil-affected open water area of 49 km2 on day 5 with ice cover, while without ice cover it reached 183 km2. The stable season with high-concentration ice showed a notable reduction in the probability of oil presence in the risk map, whereas this reduction effect was less prominent during the freezing and melting seasons. Moreover, negative correlations between initial ice concentration and oil-affected open water area were consistent, especially on day 1 with a linear regression R-squared value of 0.94, potentially enabling rapid prediction. Overall, the coupled model system serves as a useful tool for simulating oil spills in the world's largest freshwater system, particularly under icy conditions, thus enhancing the formulation of effective emergency response strategies.

Greenhouse gas emissions from U.S. crude oil pipeline accidents: 1968 to 2020

Crude oil pipelines are considered as the lifelines of energy industry. However, accidents of the pipelines can lead to severe public health and environmental concerns, in which greenhouse gas (GHG) emissions, primarily methane, are frequently overlooked. While previous studies examined fugitive emissions in normal operation of crude oil pipelines, emissions resulting from accidents were typically managed separately and were therefore not included in the emission account of oil systems. To bridge this knowledge gap, we employed a bottom-up approach to conducted the first-ever inventory of GHG emissions resulting from crude oil pipeline accidents in the United States at the state level from 1968 to 2020, and leveraged Monte Carlo simulation to estimate the associated uncertainties. Our results reveal that GHG emissions from accidents in gathering pipelines (~720,000 tCO2e) exceed those from transmission pipelines (~290,000 tCO2e), although significantly more accidents have occurred in transmission pipelines (6883 cases) than gathering pipelines (773 cases). Texas accounted for over 40% of total accident-related GHG emissions nationwide. Our study contributes to enhanced accuracy of the GHG account associated with crude oil transport and implementing the data-driven climate mitigation strategies.

A solvent-template ethyl cellulose-polydimethylsiloxane crosslinking sponge for rapid and efficient oil adsorption

Lipophilic adsorbents for oil-water separation are usually synthesized using the template method, in which hydrophobic materials are coated on a ready-made sponge. Herein, a novel solvent-template technique is used to directly synthesize a hydrophobic sponge, by crosslinking polydimethylsiloxane (PDMS) with ethyl cellulose (EC) which plays a vital role in the formation of 3D porous structure. The as-prepared sponge has advantages of strong hydrophobility, high elasticity, as well as excellent adsorption performance. In addition, the sponge can be readily decorated by nano-coatings. After the sponge was simply dipped in nanosilica, the water contact angle increases from 139.2° to 144.5°, and the maximum adsorption capacity for chiroform rises from 25.6 g/g to 35.4 g/g. The adsorption equilibrium can be reached within 3 min, and, the sponge can be regenerated by squeezing, without any change in hydrophobility or evident decline in capacity. The simulation tests of emulsion separation and oil-spill cleanup demonstrate that the sponge has great potential in oil-water separation.

In Situ Burning for Oil Spill Response in the Arctic: Recovery and Quantification of Chemical Herding Agent OP-40 from Burned Oil Residues

In situ burning (ISB) aided by OP-40 is one of the best suited and effective oil spill response techniques for Arctic conditions. However, the fate of OP-40 in the environment after an ISB event is not fully understood, especially the amount of OP-40 remaining within the burned oil residues. Previous studies reported partial accumulation of OP-40 in water, and no OP-40 was measured in the air emissions following the burn. Accumulation of OP-40 in burned oil residues is not appropriately quantified as it is challenging to process and analyze burned oil samples in the laboratory, and there exists no standard method in the literature to measure and quantify OP-40 in burned residues. In this work, we report on the development of an analytical method for the quantification of OP-40 in burned oil residues using column chromatography, followed by gas chromatography-mass spectrometry analysis which was successfully employed to measure more than 90% of the applied OP-40 in the burned residues for controlled bench-scale burns. Additionally, the robustness of the developed method was further tested by measuring OP-40 in burn residues from ISBs conducted at different oil-water emulsion ratios (60-100% oil) and water temperatures (4-35 °C), wherein known amounts of OP-40 were added to the residues. Results indicate that the method is equally effective for different oil-water emulsions, but the OP-40 recoveries (89.2-115.6%) are significantly higher at warmer temperatures than the OP-40 recoveries (87.0-103.3%) at colder temperatures. Overall, the method developed in this work could assist in the understanding of the fate of OP-40 in a potentially important environmental matrix of burned oil residues that are left behind sometimes long (weeks to years) after an ISB event.

Polyolefin-based electrospun fibrous matrices embedded with magnetic nanoparticles for effective removal of viscous oils

In this work, we present a poly (ethylene-co-1-octene)-based fibrous matrix prepared via electrospinning for highly efficient removal of viscous oils. The sorbent consisting of linear low density polyethylene (LLDPE) allows selective absorption of crude oil spills at the water surface without the need for additional isolation of the matrix prior to the refining process. Moreover, the high specific pore volume of the LLDPE sorbent with uniform fibrous morphology was shown to enable the sorbent reach 81.5 ± 5.9% of its equilibrium absorption capacity within 5 min. Furthermore, magnetic nanoparticles (MNP) are incorporated into each fiber comprising the matrix to facilitate the recovery process via external magnetic field without altering the intrinsic absorption capacity. We envision that these sorbents offer a sustainable route for the quick and thorough clean-up of spilled oil due to their high absorption capacity, fast absorption rate, ease of recovery, and absence of secondary waste.

Dispersants as an oil spill clean-up technique in the marine environment: A review

Oil is a major source of energy in the industrial world. Exploitation of oil and rigging activities, transportation via sea, and many other mechanical failures lead to oil spills into the marine environment. In view of these, the suitability and effectiveness of oil spill response methods have always been a topical discussion worldwide. It has become necessary, now than ever, for existing spill response methods used to remove oil from the environment to be improved upon and more importantly, develop new response materials that are sustainable and environmentally friendly. There exist surfactants in nature that are non-toxic and biodegradable, which can be explored to produce potential dispersants to help remove oil safely from the surface of marine water. This review comprises of the works and resourceful materials produced by various researchers and agencies in the field of oil spill response, placing emphasis on the use of dispersants in the marine environment.

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Smart dispersants have the potential to minimize dispersant wastage.

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Biodegradable dispersants may bring a closure to discussions on toxicity.

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Bio-based formulations have the potential to replace chemical based dispersants.

Application of chemical herders do not increase acute crude oil toxicity to cold-water marine species

Chemical herders may be used to sequester and thicken surface oil slicks to increase the time window for performing in situ burning of spilled oil on the sea surface. For herder use to be an environmentally safe oil spill response option, information regarding their potential ecotoxicity both alone and in combination with oil is needed. This study aimed at assessing if using herders can cause toxicity to cold-water marine organisms. Our objective was to test the two chemical herders Siltech OP-40 (OP-40) and ThickSlick-6535 (TS-6535) with and without oil for toxicity using sensitive life stages of cold-water marine copepod (Calanus finmarchicus) and fish (Gadus morhua). For herders alone, OP-40 was consistently more toxic than TS-6535. To test herders in combination with oil, low-energy water accommodated fractions (LE-WAFs, without vortex) with Alaskan North Slope crude oils were prepared with and without herders. Dissolution of oil components from surface oil was somewhat delayed following herder application, due to herder-induced reduction in contact area between water and oil. The LE-WAFs were also used for toxicity testing, and we observed no significant differences in toxicity thresholds between treatments to LE-WAFs generated with oil alone and oil treated with herders. The operational herder-to-oil ratio is very low (1:500), and the herders tested in the present work displayed acute toxicity at concentrations well above what would be expected following in situ application. Application of chemical herders to oil slicks is not expected to add significant effects to that of the oil for cold-water marine species exposed to herder-treated oil slicks.

Comparative Toxicity of Oil Spill Herding Agents to Aquatic Species

Chemical herding agents are surfactant mixtures used to coalesce spilled oil and increase slick thickness to facilitate mechanical recovery or in situ burning. Only two herders are currently listed on the United States' National Oil and Hazardous Substances Pollution Contingency Plan or National Contingency Plan product schedule for potential use in spill response: the surface collecting agents Siltech OP-40™ and ThickSlick 6535™. Toxicity data for spill response agents are frequently available only for two estuarine species, mysid shrimp (Americamysis bahia) and inland silversides (Menidia beryllina), and are particularly limited for herding agents. Toxicity can vary over several orders of magnitude across product type and species, even within specific categories of spill response agents. Seven aquatic species were tested with both Siltech OP-40™ and ThickSlick 6535™ to evaluate acute herder toxicity and relative species sensitivity. The toxicity assessment included: acute tests with A. bahia and M. beryllina, the freshwater crustacean Ceriodaphina dubia, and the freshwater fish Pimephales promelas; development of the echinoderm Arbacia unctulate; and growth of a freshwater alga Raphidocelis subcapitata and marine alga Dunaliella tertiolecta. Siltech acute toxicity values ranged from 1.1 to 32.8 ppm. ThickSlick acute toxicity values ranged from 2.2 to 126.4 ppm. The results of present study show greater toxicity of Siltech compared to ThickSlick with estimated acute hazard concentrations intended to provide 95% species protection of 1.1 and 3.6 ppm, respectively, on empirical data and 0.64 and 3.3 ppm, respectively, with the addition of interspecies correlation data. The present study provides a greater understanding of species sensitivity of these two oil spill response agents. Environ Toxicol Chem 2022;41:1311-1318. © 2022 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Bioherder Generated by Rhodococcus erythropolis as a Marine Oil Spill Treating Agent

There is an urgent call for contingency planning with effective and eco-friendly oil spill cleanup responses. In situ burning, if properly applied, could greatly mitigate oil in water and minimize the adverse environmental impacts of the spilled oil. Chemical herders have been commonly used along with in situ burning to increase the thickness of spilled oil at sea and facilitate combustion. These chemical surfactant-based agents can be applied to the edges of the oil slick and increase its thickness by reducing the water–oil interfacial tension. Biosurfactants have recently been developed as the next generation of herds with a smaller environmental footprint. In this study, the biosurfactant produced by Rhodococcus erythropolis M25 was evaluated and demonstrated as an effective herding agent. The impact of environmental and operational factors (e.g., temperature, herder dose, spilled oil amount, water salinity, and operation location) on its performance was investigated. A five-factor fractional design was applied to examine the importance of these factors and their impact on herding effectiveness and efficiency. The results of this study showed that higher temperature and a higher dose of herder could result in an increased oil slick thickness changing rate. Differences in water salinity at the same temperature led to the same trend, that is, the herding process effectively goes up with increasing herder–oil ratio (HOR). Further large-scale testing needs to be conducted for evaluating the applicability of the developed bioherder in the field.

Dissolved organic matter production from herder application and in-situ burning of crude oil at high latitudes: Bioavailable molecular composition patterns and microbial community diversity effects

Chemical herders and in-situ burning (ISB) are designed to mitigate the effects that oil spills may have on the high latitude marine environment. Little information exists on the water solubilization of petroleum residues stemming from chemically herded ISB and whether these bioavailable compounds have measurable impacts on marine biota. In this experiment, we investigated the effects of Siltech OP40 and crude oil ISB on a) petroleum-derived dissolved organic matter (DOM_HC) composition and b) seawater microbial community diversity over 28 days at 4 °C in aquarium-scale mesocosms. Ultra-high resolution mass spectrometry and fluorescence spectroscopy revealed increases in aromaticity over time, with ISB and ISB+OP40 samples having higher % aromatic classes in the initial incubation periods. ISB+OP40 contained a nearly 12-fold increase in the number of DOM_HC formulae relative to those before ISB. 16S rRNA gene sequencing identified differences in microbial alpha diversity between seawater, ISB, OP40, and ISB+OP40. Microbial betadiversity shifts were observed that correlated strongly with aromatic/condensed relative abundance and incubation time. Proteobacteria, specifically from the genera Marinomonas and Perlucidibaca experienced -22 and +24 log₂-fold changes in ISB+OP40 vs. seawater, respectively. These findings provide an important opportunity to advance our understanding of chemical herders and ISB in the high latitude marine environment.

Oil spills: impacts and perspectives of treatment technologies with focus on the use of green surfactants

Oil spills into the oceans cause irreparable damage to marine life and harms the coastal population of the affected areas. The main measures to be taken in response to an oil spill are to reduce the impact on marine life, prevent oil from reaching the shore through its recovery, and accelerate the degradation of unrecovered oil. Any environmental damage can be reduced if the spilled oil is removed from the water quickly and efficiently. Therefore, it is essential to know the treatment strategies for spilled oils. Several technologies are currently available, including booms, skimmers, in situ burning, use of adsorbents, dispersants/surfactants, and bioremediation. The selection of the type of treatment will depend not only on the effectiveness of the technique, but mainly on the type of oil, amount spilled, location, weather, and sea conditions. In this review, the characteristics of oil spills, their origin, destination, and impacts caused, including major accidents around the world, are initially addressed. Then, the main physical, chemical, and biological treatment technologies are presented, describing their advances, advantages, and drawbacks, with a focus on the use of green surfactants. These agents will be described in detail, showing the evolution of research, recent studies, patents, and commercialized products. Finally, the challenges that remain due to spills, the necessary actions, and the prospects for the development of existing treatment technologies are discussed, which must be linked to the use of combined techniques.

Mussel-Inspired and In Situ Polymerization-Modified Commercial Sponge for Efficient Crude Oil and Organic Solvent Adsorption

Oil spills and pollution of oily wastewater from the industrial field have not only caused serious economic losses but also imposed a huge threat to human beings. To solve these issues, the development of advanced materials and technologies for the purification of oily wastewater has garnered great concern and become a central topic. Hence, a superhydrophobic polyurethane (PU) sponge adsorbent is designed via mussel-inspired coatings by double bonds to PU sponge, followed by in situ polymerization with 1-hexadecene. The prepared PU sponge adsorbent (PU@DB@16ene sponge) showed outstanding mechanical properties including low density, high porosity, and compression recovery ability. Moreover, the prepared PU@DB@16ene sponge showed excellent adsorption of oils and organic solvents (up to 187 g g^-1) and exhibited superior recyclability. Particularly, when the PU@DB@16ene sponge was applied in the continuous and rapid separation of oils and organic solvents, it still showed desired properties at a rapid velocity of 8.3 L m^-3 s^-1. Additionally, the PU@DB@16ene sponge could not only adsorb organic solvents in laboratories but also adsorb crude oil and industrial waxy oil in practice. Therefore, we proposed a simple and convenient method to construct PU sponge absorbents with great application prospects, which would be highly valuable for crude oil and organic solvents cleanup.

A methodology for Response Gap Analysis in offshore oil spill emergency management

In case of offshore oil spills, the success of emergency response largely depends on the meteorological and oceanographic conditions during and after the spill, which are expressed by a set of different environmental factors. A "gap" in the response may be caused by unfavourable environmental factors that could limit its effectiveness or even impede it. In this context, Response Gap Analysis (RGA) studies identify the environmental factors negatively influencing the emergency response in a given sea area and aim at assessing the percentage of time during which the response would be without success or impossible to deploy. In the present study, a new RGA methodology is described, based on 11 environmental factors. Different oil spill response strategies are considered: mechanical recovery, application of dispersants by vessel and by aircraft, and in-situ burning. A case-study is presented to demonstrate the methodology and discuss the outcomes obtained by its application.

A Mechanically Flexible Superhydrophobic Rock Wool Modified with Reduced Graphene Oxide-Chloroperene Rubber for Oil-Spill Clean-Up

The leakage of industrial oil and organic wastewater discharge has caused serious damage to the natural environment and ecology. Therefore, implementation of a low-cost and high-performance adsorbent material is of great significant. This work reports the preparation of superhydrophobic rock wool (RW) for efficient clean-up of oil and organic solvents. The modified RW is prepared by coating a commercial RW with reduced graphene oxide (RGO) nanosheets under hydrothermal treatment. To improve the adhesion between the RGO nanosheets and RW, a film of chloroperene rubber is deposited on the RW surface followed by modification with RGO. The modified RW possesses superhydrophobicity and superoleophilicity with a water contact angle of 152.4°, and it is used for separation of oil-water mixture. The modified RW exhibits excellent mechanical elasticity and durability when compared with commercial one, and the adsorbed oils are recycled by simple squeezing. Its oil adsorption capacities are maintained above 95%, after several compression cycles. Importantly, the modified RW exhibits excellent photothermal properties which are beneficial for the separation of high-viscosity oils. Owing to low costs, versatility, and scalability in production, the modified RW can be regarded as a suitable choice for large-scale oil/water separation.

Oil Spill Sorber Based on Extrinsically Magnetizable Porous Geopolymer

Environmental impacts are increasingly due to the human polluting activities. Therefore, there is a need to develop technologies capable of removing contamination and driving the impacted environment as close as possible to its inherent characteristics. One of the major problems still faced is the spill of oil into water. Therefore, to solve the environmental problem, this work shows the use of magnetically modified geopolymer materials as an oil remover from water with a magnet’s aid. The results obtained were outstanding since the average intrinsic oil removal capability (IORC) was 150 g/g. The presented IORC is the largest found in the materials produced by our research group, constituting an extremely encouraging result, mainly because of the ease of preparing the magnetic geopolymer system. Furthermore, the low cost of production and the material’s capability to be reused as filler of polymer or even cementitious matrices allows us to project that this nanocomposite can be widely used, constituting an economically viable alternative for more efficient environmental recovery processes.

A comprehensive review on the applications of functionalized chitosan in petroleum industry

The biomaterials have gained the attention for utilization as sustainable alternatives for petroleum-derived products due to the rapid depletion of petroleum resources and environmental issues. Chitosan is an economical, renewable and abundant polysaccharide having unique molecular characteristics. Chitosan is derived by deacetylation of chitin, a natural polysaccharide existing in insects' exoskeleton, outer shells of crustaceans, and some fungi cell walls. Chitosan is widely used in numerous domains like agriculture, food, water treatment, medicine, cosmetics, fisheries, packaging, and chemical industry. This review aims to account for all the efforts made towards chitosan and its derivatives for utilization in the petroleum industry and related processes including exploration, extraction, refining, transporting oil spillages, and wastewater treatment. This review includes a compilation of various chemical modifications of chitosan to enhance the petroleum field's performance and applicability.

Design aspects of (super)hydrophobic mesh based oil-collecting device with improved efficiency

Effective treatment of frequent oil spills and endless discharged oily wastewater is crucial for the ecosystem and human health. In the past two decades, the collection of oil from water surface has been widely studied through the simple fabrication of superhydrophobic meshes with various coating materials, but little attention is paid to the design aspects of the meshes based oil-collecting device and practical oil collection. Here, 3D-printing devices with different configurations of (super)hydrophobic meshes, circular truncated cone (CTC), cylinder and inverted CTC, and the same inverted cone-shaped structure (below the meshes for temporary oil storage) are investigated. Results demonstrate that the CTC meshes based device especially for an oblate one not only shows higher stability and discharge of the collected oils than previous reports, but also allows floating oils to enter the (super)hydrophobic mesh faster. We anticipate that future success in developing high-performance (super)hydrophobic meshes and the further optimization of the CTC mesh-based device parameters will make our proposed device more practical for the treatment of real-life oil spills.

In situ oils/organic solvents cleanup and recovery using advanced oil-water separation system

Removing contaminants from wastewater is critical towards resolving global water pollution problems. However, the variety of oily contaminants composition, and the unsatisfactory performance and efficiency of current separation systems are still big challenges, thus developing efficient and scalable oil-water separation (OWS) methods is needed. Here, the performance of a novel pilot-scale oil-water separator skimmer (OWSS) prototype is fully investigated using an upflow fixed bed column system packed with polypropylene (PP) fibrous sorbent materials for dual continuous OWS and in situ oils/organic solvents recovery. The mechanism of oil sorption by the PP fibrous sorbents, as well as capillary and vacuum assisted oil flow within the inter-fiber voids is fully explored. A series of pilot-scale column experiments were performed with different bed heights (7.5-30 cm) and using different types of oil/solvent in order to determine their influence on the oil flux, OWS efficiency and recovered organic solvent purity. The OWSS provided excellent and stable performance. A trade-off relationship between oil flux and OWS efficiency can be obtained: The maximum flux was attained at the lowest sorbent bed height (7.5 cm), while the maximum OWS efficiency (>99%) was achieved at the highest sorbent bed height (30 cm). The materials' morphology and wettability were examined showing outstanding stability and recyclability, which demonstrates their efficient integration into the overall OWSS. This study is expected to provide significant insights into the feasibility and scalability of an advanced, environmentally friendly, and relatively cost-effective OWS system, towards promising industrial implementation to overcome large-scale oil spill cleanup and oily wastewater treatment shortcomings.

Selection of oil spill response method in Arctic offshore waters: A fuzzy decision tree based framework

A fuzzy decision tree (FDT) based framework was developed to facilitate the selection of suitable oil spill response methods in the Arctic. Hypothetical oil spill cases were developed based on six identified attributes, while the suitability of three spill response methods (mechanical containment and recovery, use of chemical dispersants, and in-situ burning) for each spill case was obtained based on expert judgments. Fuzzy sets were used to address the associated uncertainties, and FDTs were then developed through generating: i) one decision tree for all three response methods (FDT-AP1) and ii) one decision tree for each response method and the development of linear regression models at terminal nodes (FDT-LR). The FDT-LR approach exhibited higher prediction accuracy than the FDT-AP1 approach. A maximum of 100% accurate predictions could be achieved for testing cases using it. On average, 75% of suitable oil spill response methods out of 10,000 performed iterations were predicted correctly.

Advances in Remote Sensing Technology, Machine Learning and Deep Learning for Marine Oil Spill Detection, Prediction and Vulnerability Assessment

Although advancements in remote sensing technology have facilitated quick capture and identification of the source and location of oil spills in water bodies, the presence of other biogenic elements (lookalikes) with similar visual attributes hinder rapid detection and prompt decision making for emergency response. To date, different methods have been applied to distinguish oil spills from lookalikes with limited success. In addition, accurately modeling the trajectory of oil spills remains a challenge. Thus, we aim to provide further insights on the multi-faceted problem by undertaking a holistic review of past and current approaches to marine oil spill disaster reduction as well as explore the potentials of emerging digital trends in minimizing oil spill hazards. The scope of previous reviews is extended by covering the inter-related dimensions of detection, discrimination, and trajectory prediction of oil spills for vulnerability assessment. Findings show that both optical and microwave airborne and satellite remote sensors are used for oil spill monitoring with microwave sensors being more widely used due to their ability to operate under any weather condition. However, the accuracy of both sensors is affected by the presence of biogenic elements, leading to false positive depiction of oil spills. Statistical image segmentation has been widely used to discriminate lookalikes from oil spills with varying levels of accuracy but the emergence of digitalization technologies in the fourth industrial revolution (IR 4.0) is enabling the use of Machine learning (ML) and deep learning (DL) models, which are more promising than the statistical methods. The Support Vector Machine (SVM) and Artificial Neural Network (ANN) are the most used machine learning algorithms for oil spill detection, although the restriction of ML models to feed forward image classification without support for the end-to-end trainable framework limits its accuracy. On the other hand, deep learning models’ strong feature extraction and autonomous learning capability enhance their detection accuracy. Also, mathematical models based on lagrangian method have improved oil spill trajectory prediction with higher real time accuracy than the conventional worst case, average and survey-based approaches. However, these newer models are unable to quantify oil droplets and uncertainty in vulnerability prediction. Considering that there is yet no single best remote sensing technique for unambiguous detection and discrimination of oil spills and lookalikes, it is imperative to advance research in the field in order to improve existing technology and develop specialized sensors for accurate oil spill detection and enhanced classification, leveraging emerging geospatial computer vision initiatives.

Research Progress and Prospects of Marine Oily Wastewater Treatment: A Review

Oily wastewater from shipping waste and marine accidents have seriously polluted the marine environment and brought great harm to human production and health. With the increasing awareness of environmental protection, the treatment of marine oily wastewater has attracted extensive attention from the international community. Marine oily wastewater has various forms and complex components, so its treatment technology faces great challenges. Sources, types, supervision, and treatment of marine oily wastewater are introduced in this paper. The research progress of marine and ship’s oily wastewater treatment technologies in recent years are reviewed from the perspectives of physical treatment, chemical treatment, biological treatment, and combined treatment, respectively. Principles and characteristics of all kinds of technologies were analyzed. In addition, this paper shows that multiple processing technologies used in combination for the purpose of high efficiency, environmental protection, economy, and energy conservation are the future development trend.

Chemical herding of weathered crude oils for in-situ burning

Mid-scale ISB experiments were conducted in a large water-basin (20 m² × 1 m) in order to assess the applicability of chemical herding of weathered crude oil spills on water in association with in-situ burning (ISB). A silicone-based chemical herding agent, OP-40, was used to confine, or herd, three different crude oils (Siri, Grane and Oseberg blend) at various weathering degrees. The herding agent was capable of obtaining the minimum required oil slick thickness for ignition and subsequent flame spread in most of the experiments, but not for the strongly weathered oils. Also, the herding agent was capable of re-thickening the oil slick after flame extinction. The burning efficiency results indicate that the method can be viable for ISB with herders at a larger scale, and suggest that the burning efficiency scales with the amount of crude oil. Sinking behaviour of residues was also observed and quantified, as such a behaviour can pose a serious environmental threat in real scenarios.