Environmental Impact Of Oil Spills Research Articles

Immobilization of lipase enzyme extracted from thermophilic Bacillus licheniformis 14T local isolate

Background: Currently, lipase enzymes are considered important bio-catalysts in many industries due to their unique properties in catalyzing various types of reactions in aqueous solutions. By targeting hydrocarbons in the oil, lipase enzymes contribute to the breakdown of hydrocarbons, reducing the environmental impact of oil spills and facilitating the remediation of contaminated areas.Methods: A thermostable lipase from local isolate Bacillus licheniformis 14T has been immobilized on four different supports that include the inactivated chitosan beads, activated chitosan beads with glutaraldehyde, inactivated chitosan-alginate beads, and activated chitosan-alginate beads with glutaraldehyde.Results The purified free lipase enzyme exhibited the highest enzymatic activity at 34.6 units/ml, surpassing all immobilized enzymes. Specific activity increased to 96.25 and 79.03 unit/mg protein for activated chitosan beads and activated chitosan-alginate beads, while decreasing to 52.95 and 46.05 unit/mg protein for inactivated chitosan beads and inactivated chitosan-alginate beads compared to the free enzyme. Optimal conditions for the immobilized enzyme differed, with the highest enzyme activity achieved after 60 minutes at 60°C and pH 8, reaching 48.6, 70.23, 43.12, and 61.2 units/ml on various supports, contrasting with the free enzyme's peak activity after 30 minutes at 50°C and pH 7.Conclusions: Immobilizing the lipase enzyme increases the specific activity of the immobilized enzyme on the supports of activated chitosan beads with, also the immobilization process led to a change in the optimal conditions for the activity of the immobilized enzyme compared with the optimal conditions of free enzyme.Keywords: Lipase; Bacillus licheniformis; Immobilization; Chitosan; Alginate

Optimization of a bio-based drilling fluid from waste Dacryodes Edulis (local pear) for oil exploration

This study focused on the development and optimization of a bio-based drilling fluid from local pear seed for oil exploration, which can help lessen the environmental impact of oil spills. Local pear seed being a biodegradable material was collected, prepared, its oil extracted, modified and optimized to obtain an eco-friendly and cost-effective drilling fluid. The selected materials used for this study was Local pear oil. The drilling fluid was characterized for proximate parameters and ultimate parameters. The prepared drilling fluid was optimized using response surface methodology (RSM) provided by Design-Expert software 13.0. Central composite design (CCD) was applied to study the variables affecting rheology of drilling fluid. The process factors which include pH (A), viscosity (B), mud density (c), temperature (D), rheology (E) interacted to produce the response (drilling fluid yield) for the studied sample. The optimized drilling fluid yield and the optimum values were obtained through iterations of one hundred (100) solutions and the best yield was selected at iteration number seven (95th solution), at a pH of 1, Viscosity of 119.783cP, mud density of 10.473kg/L, Temperature of 100°C, and Rheology of 76.809s-1, and the optimized drilling fluid yield value was 91.144%. The acidity and the alkalinity of the drilling fluid were measured by the concentration of the 9.5 ion in the fluid. Therefore, the biomaterial studied has demonstrated its optimal effectiveness and potential application as an additive for the development of drilling fluid for oil exploration.

Effects of suspended particles and dispersants on marine oil snow formation of crude oil/diesel oil.

Marine oil snow (MOS) potentially forms after an oil spill. To fully understand the mechanism of its formation, we investigated the effects of suspended particles (SP) and dispersants on MOS formation of crude oil and diesel oil by laboratory experiments. In the crude oil experiment, the SP concentration of 0.2 g L-1 was more suitable for crude oil MOS formation. The addition of dispersants significantly stimulated N and TV during MS/MOS formation of SP at 0.4 g L-1 and 0.8 g L-1 concentration (p < 0.05). Without SP, the dispersants also stimulated crude oil MOS formation. Furthermore, the concentration of SP had a significantly positive effect on the reduction of the total amount of N-alkanes (p < 0.05). In the diesel oil experiment, after adding dispersants to diesel oil, the maximum N, Dm, and TV values at a SP concentration of 0.2 g L-1 were significantly higher than those at 0.4 g L-1 and 0.8 g L-1 (p < 0.05). Besides, we found that dispersants stimulated MOS formation in diesel oil at a SP concentration of 0.2 g L-1. However, the dispersants had an inhibitory effect on diesel oil MOS formation without SP. Notably, the MOS formed by diesel oil appeared white, unlike the black MOS associated with crude oil. These findings are important for the environmental impact of oil spills and elevated SP concentrations.

Green Material From Natural Rubber-Coated Fabric As A Sustainable Solution In Removing Oil From Water

Oil removal from water has become more important for environment sustainability since there are many cases of oil leakage accidents. Oil spills, whether caused by accidents or other factors, can have devastating effects on aquatic ecosystems and wildlife. To clean up by utilizing green materials, it can mitigate the environmental impact of oil spills and align with the principles of conservation science. Therefore, in this work, an attempt was made to clean oil contamination using rubber foam attached with cotton fabric. The enhancement of hydrophobicity would increase the efficiency of oil removal. The cotton fabric was coated by natural rubber (NR) foam and subsequently treated with hexadecyltrimethoxysilane (HDTMS) as hydrophobic agent. The results show the treated NR-coated fabric exhibited excellent oil absorption, oil selectivity and completely removed the oily layer from water. It is because hydrophobic enhancement of cotton fabric and rubber foam surfaces were achieved at 157° and 140°, respectively. The formation of hydrophobic agent with rough surface was revealed by SEM micrographs. From the results, the prepared NR-coated fabric presented an attractive hydrophobic property with simple preparation and high efficiency of oil removal. It could be said that NR-coated fabric is a green material potentially used as a perfect oil-separator to relieve the pollution from oil contamination. Conservationists and researchers can work together to raise awareness about the benefits of using green materials for oil spill cleanup, fostering a sense of environmental stewardship.

Deep Learning-Based Approaches for Oil Spill Detection: A Bibliometric Review of Research Trends and Challenges

Oil spill detection and mapping using deep learning (OSDMDL) is crucial for assessing its impact on coastal and marine ecosystems. A novel approach was employed in this study to evaluate the scientific literature in this field through bibliometric analysis and literature review. The Scopus database was used to evaluate the relevant scientific literature in this field, followed by a bibliometric analysis to extract additional information, such as architecture type, country collaboration, and most cited papers. The findings highlight significant advancements in oil detection at sea, with a strong correlation between technological evolution in detection methods and improved remote sensing data acquisition. Multilayer perceptrons (MLP) emerged as the most prominent neural network architecture in 11 studies, followed by a convolutional neural network (CNN) in 5 studies. U-Net, DeepLabv3+, and fully convolutional network (FCN) were each used in three studies, demonstrating their relative significance too. The analysis provides insights into collaboration, interdisciplinarity, and research methodology and contributes to the development of more effective policies, strategies, and technologies for mitigating the environmental impact of oil spills in OSDMDL.

Advancing hyper-crosslinked materials with high efficiency and reusability for oil spill response

Developing materials with high efficiency for recovering oil to mitigate the environmental impact of oil spills has always been a challenging task. A commercial melamine formaldehyde sponge was coated with an optimised superhydrophobic/superoleophilic hyper-crosslinked polymer and applied to the removal of crude oil from oil-in-water emulsions for the improvement of oil spill clean-up processes. The high surface area, porosity, hydrophobicity, and selectivity of oil over water made the hyper-crosslinked polymer coated sponge (HPCS) an ideal sorbent for efficient oil/water separation. The system was able to strip crude oil from water emulsions of 1000 ppm to a negligible level of 2 ppm oil with minimal amounts of the HPCS material. More importantly, the HPCS material could be reused via a simple mechanical compression process, and the uptake capacity was retained over ten cycles. For five cycles of oil adsorption/mechanical compression the HPCS was able to provide water filtrate with oil concentrations of under 15 ppm. This is an effective and economical recovery system, removing the need for consistent solvent washing and drying processes. These results suggest that the HPCS is a promising material for oil/water separation and recovery under challenging conditions.

Assessing the environmental impact of oil spills in beach environments: a case study using the Capacitive Resistivity Method

The accident involving oil spill that occurred on the Brazilian coast in 2019 reached 2,880 km in extension, and more than 200 tons of oily material was removed from coastal environments in the northeast of the country in about five months. In the impact on beach environment there may still be non-visible residues and its by-products in subsurface, so that geophysical prospecting can be the suitable to evaluate the presence of remaining material. The evolution of environmental studies has required new research technologies. Geophysical methods have shown to be efficient in environmentalstudies, with the use of relatively new methods in Brazil that provide results with excellent coverage in the area and quickly. Among these methods stands out the Capacitive Resistivity Method. Environmental research work with this method has been reported with good results, but it is necessary to take into account the operational physical bases of the method so that the data is reliable. This work presents the results of tests carried out in a beach environment that was affected by oil. This environment is characterized by a medium of high conductivity, where data acquisition with equipment configured with smaller dipolar cables results in extremely noisy data. On the other hand, the configuration with larger dipolar cables allowed the transmission of higher electrical current to the ground resulting in the acquisition of good quality data. The results showed that there are no more indications of oil residues on the beach studied.

Numerical simulation of the environmental impact of oil spill in the Liuheng Island of Zhoushan City

At present, numerical models of 2D tidal current and oil spill have been widely used in simulating the diffusion and spread of spilled oil. Thus, this paper adopts the MIKE21_FM hydrodynamic model, and establishes a 2D tidal current dynamic model based on unstructured meshes in the Liuheng Island of Zhoushan city. After verification by the measured data, it can be found that this model can reflect the hydrodynamic characteristics perfectly, and provide sufficient hydrodynamic conditions for the simulation of oil spill. Based on that, the MIKE21/3 OS model is applied for predicting the risk of oil spill. Accordingly, 8 working conditions are simulated to track the spread and sweeping area of spilled oil. The results show that both oil spill time, tidal current and wind direction can affect oil diffusion, while wind direction is the most dominant factor. Moreover, the sweeping area increases gradually with time, and the maximum area reaches 2018.95 km2 after 72 hours at ebb tide under the wind direction of WNW.

Metagenomic Insights Into the Mechanisms for Biodegradation of Polycyclic Aromatic Hydrocarbons in the Oil Supply Chain.

Petroleum is a very complex and diverse organic mixture. Its composition depends on reservoir location and in situ conditions and changes once crude oil is spilled into the environment, making the characteristics associated with every spill unique. Polycyclic aromatic hydrocarbons (PAHs) are common components of the crude oil and constitute a group of persistent organic pollutants. Due to their highly hydrophobic, and their low solubility tend to accumulate in soil and sediment. The process by which oil is sourced and made available for use is referred to as the oil supply chain and involves three parts: (1) upstream, (2) midstream and (3) downstream activities. As consequence from oil supply chain activities, crude oils are subjected to biodeterioration, acidification and souring, and oil spills are frequently reported affecting not only the environment, but also the economy and human resources. Different bioremediation techniques based on microbial metabolism, such as natural attenuation, bioaugmentation, biostimulation are promising approaches to minimize the environmental impact of oil spills. The rate and efficiency of this process depend on multiple factors, like pH, oxygen content, temperature, availability and concentration of the pollutants and diversity and structure of the microbial community present in the affected (contaminated) area. Emerging approaches, such as (meta-)taxonomics and (meta-)genomics bring new insights into the molecular mechanisms of PAH microbial degradation at both single species and community levels in oil reservoirs and groundwater/seawater spills. We have scrutinized the microbiological aspects of biodegradation of PAHs naturally occurring in oil upstream activities (exploration and production), and crude oil and/or by-products spills in midstream (transport and storage) and downstream (refining and distribution) activities. This work addresses PAH biodegradation in different stages of oil supply chain affecting diverse environments (groundwater, seawater, oil reservoir) focusing on genes and pathways as well as key players involved in this process. In depth understanding of the biodegradation process will provide/improve knowledge for optimizing and monitoring bioremediation in oil spills cases and/or to impair the degradation in reservoirs avoiding deterioration of crude oil quality.

Beyond Thresholds: A Holistic Approach to Impact Assessment Is Needed to Enable Accurate Predictions of Environmental Risk from Oil Spills.

The risk assessment for the environmental impact of oil spills in Australia is often conducted in part using a combination of spill mapping and toxicological thresholds derived from laboratory studies. While this process is useful in planning operational responses, such as where to position equipment stockpiles and whether to disperse oil, and can be used to identify areas near the spill site where impacts are likely to occur, it cannot accurately predict the environmental consequences of an oil spill or the ecosystem recovery times. Evidence of this disconnect between model predictions and observed impacts is the lack of a profound effect of the Deepwater Horizon wellhead blowout on recruitment to fisheries in the northern Gulf of Mexico, contrary to the predictions made in the Natural Resources Damage Assessment and despite the occurrence of impacts of the spill on marine mammals, marshes, and deep water ecosystems. The incongruity between predictions made with the current approach using threshold monitoring and impacts measured in the field results from some of the assumptions included in the oil spill models. The incorrect assumptions include that toxicity is acute, results from dissolved phase exposure, and would be readily reversible. The toxicity tests from which threshold models are derived use members of the ecosystem that are easily studied in the lab but may not represent the ecosystem as a whole. The test species are typically highly abundant plankton or planktonic life stages, and they have life histories that account for rapid changes in environmental conditions. As a consequence, these organisms recover quickly from an oil spill. The interdependence of ecosystem components, including the reliance of organisms on their microbiomes, is often overlooked. Additional research to assess these data gaps conducted using economically and ecologically relevant species, especially in Australia and other understudied areas of the world, and the use of population dynamic models, will improve the accuracy of environmental risk assessment for oil spills. Integr Environ Assess Manag 2020;16:813-830. © 2020 SETAC.

Photochemical oxidation reduced the efficacy of aerial dispersants applied in response to the Deepwater Horizon spill.

Chemical dispersants are one of many tools used to mitigate the overall environmental impact of oil spills. In principle, dispersants break up floating oil into small droplets that disperse into the water column where they are subject to multiple fate and transport processes. The effectiveness of dispersants typically decreases as oil weathers in the environment. This decrease in effectiveness is often attributed to evaporation and emulsification, with the contribution of photochemical weathering assumed to be negligible. Here, we aim to test this assumption using Macondo well oil released during the Deepwater Horizon spill as a case study. Our results indicate that the effects of photochemical weathering on Deepwater Horizon oil properties and dispersant effectiveness can greatly outweigh the effects of evaporative weathering. The decrease in dispersant effectiveness after light exposure was principally driven by the decreased solubility of photo-oxidized crude oil residues in the solvent system that comprises COREXIT EC9500A. Kinetic modeling combined with geospatial analysis demonstrated that a considerable fraction of aerial applications targeting Deepwater Horizon surface oil had low dispersant effectiveness. Collectively, the results of this study challenge the paradigm that photochemical weathering has a negligible impact on the effectiveness of oil spill response and provide critical insights into the "window of opportunity" to apply chemical dispersants in response to oil spills in sunlit waters.

Sustainable stabilization of oil in water emulsions by cellulose nanocrystals synthesized from deep eutectic solvents

There is an urgent global need to develop novel types of environmentally safe dispersing chemicals from renewable resources in order to reduce the environmental impact of oil spills. For this goal, cellulose, the most abundant natural polymeric source, is a promising green, nontoxic alternative that could replace the current synthetic surfactants. In this study, cellulose nanocrystals (CNC) synthesized using a deep eutectic solvent (DES) and two commercially available cellulose nanocrystals were used as marine diesel oil–water Pickering emulsion stabilizers. In particular, oil in water (o/w) emulsion formation and stability of emulsified oil during storing were addressed using a laser diffraction particle size analyzer, image analysis, and oil emulsion volume examination. The particle size of the o/w reference without CNCs after dispersing was over 50 µm and coalescence occurred only a few minutes after the emulsifying mixing procedure. All three investigated CNCs were effective stabilizers for the o/w system (oil droplets size under 10 µm) by preventing the oil droplet coalescence over time (6 weeks) and resulting in a stable creaming layer. The CNCs prepared using green DES systems boasted performance comparable to that of commercial CNCs, and they showed effectiveness at 0.1% dispersant dosage.

The metabolic pathways and environmental controls of hydrocarbon biodegradation in marine ecosystems.

The metabolic pathways and environmental controls of hydrocarbon biodegradation in marine ecosystems.

A Model to Predict Rate of Dissolution of Toxic Compounds into Seawater from an Oil Spill

In this paper a semianalytical model has been proposed to predict the rate at which oil components dissolve in water when an oil spill occurs in a marine environment. The model breaks the oil into a number of pseudocomponents proportional to the number of compounds originally present in the oil and calculates the rate of dissolution for each component. In addition, the components are divided into paraffinic, naphthenic, and aromatic hydrocarbon types and the amount of dissolution of each pseudocomponent is calculated versus time. In this method the concentration of most toxic components of oil (mainly monoaromatics) is determined. The model considers variable surface area and slick thickness and requires oil specifications (i.e., American Petroleum Institute [API] gravity and boiling point) in addition to air and water temperatures and speeds. The model has been applied to a Kuwaiti crude oil and its products naphtha and kerosene samples at 20 degrees C and 40 degrees C. The results could be useful in selection of an appropriate method for oil spill clean up as well as simulation of environmental impact of oil spill from toxicity points of view.

Long-term Environmental Impact of Oil Spills

Oil contamination may persist in the marine environment for many years after an oil spill and, in exceptional cases such as salt marshes and mangrove swamps, the effects may be measurable for decades after the event. However, in most cases, environmental recovery is relatively swift and is complete within 2–10 years. Where oil has been eliminated from the scene, the long-term environmental impacts are generally confined to community structure anomalies that persist because of the longevity of the component species.

MARINE POLLUTION CONTINGENCY PLANNING—RECENT CHANGES IN UNITED KINGDOM ORGANIZATION

ABSTRACT The UK has recently carried out a major review of the oil pollution problem (Royal Commission Report No. 8) which has resulted in an authoritative assessment of the environmental impact of oil spills, a series of recommendations covering a wide variety of aspects of prevention and response, and government acceptance and the subsequent implementation of a number of these recommendations. This paper summarizes the essential elements of the new environmental assessment, discusses the pros and cons of the recommendations, and describes those which government has accepted. It then goes on to deal in detail with the implications of the government's acceptance of the various recommendations and records progress in their implementation. The areas it covers in detail include: A new national organization for the central integration of sea and shore response in a single unit: the Marine Pollution Control Unit (MPCU), responsible within central government to the Department of Transport New structures and procedures to facilitate interaction between central and local government Redirection of emphasis in the R&amp;D field, in the provision of sea and shore related response equipment, and in contingency planning in order to redress imbalances formerly existing between sea and shore related response Further development of the safe havens policy to facilitate salvage and cargo transfer operations Greater emphasis within the MPCU on the detection of violations of discharge regulations and the collection of evidence Arrangements for closer association between government and the oil industry in relation to provision of response equipment, the development of mutually supportive contingency planning, and response arrangements

Emissions from in situ burning of crude oil in the arctic

The results of an exploratory study of the effects of in situ crude oil spill burning on air quality in the Beaufort Sea region of the Arctic are presented. A scenario is postulated defining the amounts of oil released, the size and number of burnable oil pools, and the duration of the burning period. Estimates are made of the likely emissions of soot, CO, SO2 and metals based on literature and some experimental work. Assumptions are made about plume rise and dispersion which permit downwind concentrations of emissions to be calculated and compared with air quality objectives. Although the calculated concentrations may contain significant error because of the many assumptions, it is believed that the data demonstrate that concentrations of SO2 and CO will be acceptably low, concentrations of soot and metals will often be undesirably high within 10 km of the fires, but will be acceptably low at greater distances. It is concluded that burning may be a method of substantially reducing the adverse environmental impact of oil spills in the Arctic.

Sampling device for monitoring biodegradation of oil and other pollutants in aquatic environments

The fate of petroleum and related pollutants in the aquatic environment, particularly in estuaries and coastal regions, is of great importance if the environmental impact of oil spills and other such accidents arising from both natural causes and human error is to be properly assesed. A sampling device suitable for monitoring biodegradation under field conditions has been devised and constructed in our laboratory. The sampler has been successfully employed in monitoring biodegradation of petroleum in situ at a marshland site in the Chesapeake Bay.

Optimal oil tanker size with regard to environmental impact of oil spills

This paper considers optimal tanker size in view of the environmental effects of oil spills. A model is developed that incorporates the tradeoff between small but frequent spills with many tankers, and the relatively less frequent but larger and more concentrated spills with a smaller fleet of larger ships. A procedure is suggested to incorporate the environmental impact of oil spills in the model without quantifying them in monetary units. A closed form solution set for optimal tankers size is obtained and some numerical results are presented.