Study on the Adsorption Efficiency of Carbonized Rice Hull Adsorption Bag for the Removal of Oil from Sea Water

2013 ◽  
Vol 295-298 ◽  
pp. 1254-1257 ◽  
Author(s):  
Ying Hui Liu ◽  
Hong Xin Li ◽  
Bo Tian ◽  
Mei Yu Zhao ◽  
Yu Bo Cui

With the increasing incidence of accidental oil spills, there is now a growing worldwide concern about the urgent need to purify oil-polluted sea water and conserve the marine ecosystem. Carbonized rice hull (CRH) prepared in the open air has been studied as adsorbent for purification of oil-polluted sea water. The adsorption effects of CRH and CRH absorption bag were both investigated. The results showed that under the dosage of 20 g/L and initial oil concentration of 746, 520 and 380 μg/L, the obtained oil removal efficiencies were 59.0%,78.8% and 67.1%, respectively. The adsorption bag counterpart indicated that under the initial oil concentration of 546 μg/L, an equilibrium state was reached for all the three kinds of package bags. The obtained adsorption amounts were 21.7, 25.5, 22.8 μg/g and the corresponding removal efficiencies were 59.7%, 70.0% and 62.6%, respectively.

2013 ◽  
Vol 295-298 ◽  
pp. 1245-1248
Author(s):  
Mei Yu Zhao ◽  
Yu Bo Cui ◽  
Xin Li ◽  
Ying Hui Liu ◽  
Hong Xin Li

Oil spills and leakage accidents caused by oil exploitation, processing, transportation and use continue to pose environmental threat to global marine ecosystem. It has become an urgent task to prevent the ocean ecosystem from oil pollution and protect the marine resources. This paper introduces the negative effects of marine oil pollution and conventional treatment measures, briefly analyzes the great potential of rice hull adsorbent for purification of oil-polluted sea water and initially explored the adsorption effects of rice hull adsorbent. The experimental results indicated that after static adsorption at different dosage of rice hull adsorbent (0g, 4g, 8g, 12g, 16g, 20g), the oil removal efficiency got 65.3% when treated by rice hull adsorbent carbonized under the temperature of 350°C at dosage of 12g, which is prospective to help in treatment of marine oil residues in the future.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vaishali Chaudhary ◽  
Shashi Kumar

AbstractOil spills are a potential hazard, causing the deaths of millions of aquatic animals and this leaves a calamitous effect on the marine ecosystem. This research focuses on evaluating the potential of polarimetric parameters in discriminating the oil slick from water and also possible thicker/thinner zones within the slick. For this purpose, L-band UAVSAR quad-pol data of the Gulf of Mexico region is exploited. A total number of 19 polarimetric parameters are examined to study their behavior and ability in distinguishing oil slick from water and its own less or more oil accumulated zones. The simulation of compact-pol data from UAVSAR quad-pol data is carried out which has shown good performance in detection and discrimination of oil slick from water. To know the extent of separation between oil and water classes, a statistical separability analysis is carried out. The outcomes of each polarimetric parameter from separability analysis are then quantified with the radial basis function (RBF) supervised Support Vector Machine classifier followed with an accurate estimation of the results. Moreover, a comparison of the achieved and estimated accuracy has shown a significant drop in accuracy values. It has been observed that the highest accuracy is given by LHV compact-pol decomposition and coherency matrix with a classification accuracy of ~ 94.09% and ~ 94.60%, respectively. The proposed methodology has performed well in discriminating the oil slick by utilizing UAVSAR dataset for both quad-pol and compact-pol simulation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dimitri Kalenitchenko ◽  
Erwan Peru ◽  
Pierre E. Galand

AbstractPredicting ecosystem functioning requires an understanding of the mechanisms that drive microbial community assembly. Many studies have explored microbial diversity extensively and environmental factors are thought to be the principal drivers of community composition. Community assembly is, however, also influenced by past conditions that might affect present-day assemblages. Historical events, called legacy effects or historical contingencies, remain poorly studied in the sea and their impact on the functioning of the communities is not known. We tested the influence, if any, of historical contingencies on contemporary community assembly and functions in a marine ecosystem. To do so, we verified if different inoculum communities colonizing the same substrate led to communities with different compositions. We inoculated wood with sea water microbes from different marine environments that differ in ecological and evolutionary history. Using 16S rRNA and metagenomic sequencing, it was demonstrated that historical contingencies change the composition and potential metabolisms of contemporary communities. The effect of historical events was transient, dominated by environmental selection as, over time, species sorting was a more important driver of community assembly. Our study shows not only that historical contingencies affect marine ecosystems but takes the analysis a step further by characterizing this effect as strong but transient.


2021 ◽  
pp. 75-83
Author(s):  
I.V. Bacherikova ◽  
◽  
S.B. Grinenko ◽  
L.S. Kuznetsova ◽  
V.O. Zazhigalov ◽  
...  

The properties of some organic materials in the removal of oil from water area were studied. It was shown that available materials as technical wool and sintepon can be used as effective sorbents for petroleum removal from water area. The sample mechanical wringing of these sorbents permits to return the part of adsorbed oil for its next use. The dependence of sorption properties (the adsorbed petroleum mass, specific oil adsorption, return of the oil and selectivity of petroleum removal) and petroleum removal from the number of absorption-release cycles was established. It was established that quantity of adsorbed oil decreases in other next step of removal but mass of oil returned increases in the process of mechanical wringing. The regeneration of these adsorbents by flushing in gasoline permits to obtained the initial properties in oil removal from water area. The sorption elements in the form of bags from linen with these materials were prepared. The dependence of the amount of oil removed by these sorption elements from the time of oil clearing of the water area process was determined and the optimal parameters of petroleum removal were established. It was shown that sorption elements on the base of these materials have adsorption capacity equal to 14-16 g of petroleum/g sorbent at selectivity of petroleum removal more than 70 % and oil recovery degree more than 80 % and the possibility their reusable use on oil spill response. The obtained positive results of oil removal from water area permit to propose in extreme cases of oil spills the available industrial products as jerseys, blankest, jackets etc. use successfully for petroleum spill response. The hydrophobization of these elements permits to improve their properties in oil removal from water area. As results of sorption elements modification the increase of adsorbed oil mass and specific petroleum removal at simultaneous increase of returned oil quantity for its next use and oil removal selectivity were established. It was established that synthesized sorption elements not inferior in properties known industrial sorbents for oil removal from water area.


Author(s):  
M. Sornam

Oil spill pollution plays a significant role in damaging marine ecosystem. Discharge of oil due to tanker accidents has the most dangerous effects on marine environment. The main waste source is the ship based operational discharges. Synthetic Aperture Radar (SAR) can be effectively used for the detection and classification of oil spills. Oil spills appear as dark spots in SAR images. One major advantage of SAR is that it can generate imagery under all weather conditions. However, similar dark spots may arise from a range of unrelated meteorological and oceanographic phenomena, resulting in misidentification. A major focus of research in this area is the development of algorithms to distinguish ‘oil spills’ from ‘look-alikes’. The features of detected dark spot are then extracted and classified to discriminate oil spills from look-alikes. This paper describes the development of a new approach to SAR oil spill detection using Segmentation method and Artificial Neural Networks (ANN). A SAR-based oil-spill detection process consists of three stages: image segmentation, feature extraction and object recognition (classification) of the segmented objects as oil spills or look-alikes. The image segmentation was performed with Otsu method. Classification has been done using Back Propagation Network and this network classifies objects into oil spills or look-alikes according to their feature parameters. Improved results have been achieved for the discrimination of oil spills and look-alikes.


2015 ◽  
Vol 1 (5) ◽  
pp. e1400265 ◽  
Author(s):  
Deeksha Gupta ◽  
Bivas Sarker ◽  
Keith Thadikaran ◽  
Vijay John ◽  
Charles Maldarelli ◽  
...  

Crude oil spills are a major threat to marine biota and the environment. When light crude oil spills on water, it forms a thin layer that is difficult to clean by any methods of oil spill response. Under these circumstances, a special type of amphiphile termed as “chemical herder” is sprayed onto the water surrounding the spilled oil. The amphiphile forms a monomolecular layer on the water surface, reducing the air–sea surface tension and causing the oil slick to retract into a thick mass that can be burnt in situ. The current best-known chemical herders are chemically stable and nonbiodegradable, and hence remain in the marine ecosystem for years. We architect an eco-friendly, sacrificial, and effective green herder derived from the plant-based small-molecule phytol, which is abundant in the marine environment, as an alternative to the current chemical herders. Phytol consists of a regularly branched chain of isoprene units that form the hydrophobe of the amphiphile; the chain is esterified to cationic groups to form the polar group. The ester linkage is proximal to an allyl bond in phytol, which facilitates the hydrolysis of the amphiphile after adsorption to the sea surface into the phytol hydrophobic tail, which along with the unhydrolyzed herder, remains on the surface to maintain herding action, and the cationic group, which dissolves into the water column. Eventual degradation of the phytol tail and dilution of the cation make these sacrificial amphiphiles eco-friendly. The herding behavior of phytol-based amphiphiles is evaluated as a function of time, temperature, and water salinity to examine their versatility under different conditions, ranging from ice-cold water to hot water. The green chemical herder retracted oil slicks by up to ~500, 700, and 2500% at 5°, 20°, and 35°C, respectively, during the first 10 min of the experiment, which is on a par with the current best chemical herders in practice.


2020 ◽  
Vol 4 (2) ◽  
pp. 127
Author(s):  
Paulin Yosephin Marini ◽  
Sherlly Monica Bonsapia ◽  
Johni R.V. Korwa

<p><em>This study aims to analyze a blowout from an oil and gas leak owned by PTT Exploration and Production (PTTEP) Australasia in the Montara oil field in the Indonesian Timor Sea, and how to resolve disputes between Australia and Indonesia. A qualitative approach was used in this study, whilst the data collection technique was through library research. The theory of state responsibility, the concept of human security, and the concept of international maritime law are used to analyze disputes between Indonesia and Australia. The study found that the Montara oil spill had not only damaged the marine ecosystem but also polluted Indonesian waters. It also found that although the Australian government had formed a special commission to resolve cases and even used dispersant, it had not satisfied all parties. Several points are summarized. First, the Montara oil spill in Australia is a transnational study because the impact has crossed national borders. Secondly, UNCLOS has a weakness in the settlement of the Montara case because the Convention only provides a description related to ‘Responsibility of Each Country’ and does not specifically arrange material compensation mechanisms to countries that cause sea pollution. Third, the Montara oil spill has caused huge losses for Indonesian seaweed farmers, especially 13 districts in NTT. The recommendations are that the Indonesian government along with the Montara Victim Peoples’ Advocacy Team should continue to follow up the case of oil spills from the Montara platform and continue to fight for compensation to the Australian government and the PTTEP as the responsible party.</em></p>


2012 ◽  
Vol 11 (1-2) ◽  
pp. 100
Author(s):  
C. E. Stringari ◽  
W. C. Marques ◽  
L. F. Mello ◽  
R. T. Edit

Oil spills can generate different effects in different time scales on the marine ecosystem. The numerical modeling of this process is an important tool with low computational cost which provides a powerful appliance to environmental agencies regarding the risk management. In this way, the objective of this work is evaluate the local wind influence in a hypothetical oil spill along the Southern Brazilian shelf. The numerical simulation was carried using the ECOS model (Easy Coupling Oil System), an oil spill model developed at the Universidade Federal do Rio Grande – FURG, coupled with the tridimensional hydrodynamical model TELEMAC3D (EDF, France). The hydrodynamic model provides the velocities, salinity and temperature fields used by the oil spill model to evaluate the behavior and fate of the oil. The results suggest that the local wind influence are the main forcing driven the fate of the spilled oil. The direction and intensity of the currents are important controlling the behavior and the tridimensional transportation of the oil, on the other hand, the turbulent diffusion is important for the horizontal drift of the oil. The weathering results indicate 40% of evaporation and 80% of emulsification, and the combination of these processes leads an increasing of the oil density around 53.4 kg/m³ after 5 days of simulation.


2014 ◽  
Vol 587-589 ◽  
pp. 616-619
Author(s):  
Zheng Wang ◽  
Dong Zhang ◽  
Ping Xia ◽  
Hui Ye ◽  
Wen Qi Zhou

The removal of geosmin by powered activated carbon (PAC) was studied at laboratory to select suitable PAC type and the removal efficiencies of geosmin by PAC in different application point as an emergency method were evaluated. The adsorption efficiency of coal-based PAC on geosmin was superior to that of bamboo-based PAC. The contact time and PAC dose were two important factors that affect the removal effect of geosmin. Geosmin could be controled below 10ng/L at 200ng/L of initial concentration.


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