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Fibrous nonwoven coalescence filters are commonly utilized in gas-cleaning processes to separate liquid droplets from a gas stream, e.g., oil mists. These filters are mainly composed of micro glass fibers and in some cases, small amounts of synthetic fibers. The shape of the deposited oil on filter fibers of the filter media depends on several factors, including the oil saturation, wettability, roughness, diameter of the fibers and fiber arrangement. The oil deposits can take the form of, e.g., axially symmetric barrel-shaped droplets or larger structures, such as oil sails between adjacent fibers. Understanding the initial state of the coalescence filtration process and the impact of the deposited oil structures on the separation efficiency requires characterizing these structures. X-ray microtomography (µ-CT) and artificial intelligence tools for segmentation can be utilized to visualize, identify and analyze deposited oil structures in the micrometer region. To quantify and compare oil structures formed at three distinct filtration velocities (10, 25 and 40 cm s − 1 ) commonly utilized in industrial applications and one defined oil saturation of oleophilic coalescence filter media, applying X-ray microtomography is the main emphasis of this work. The results indicate that there is no significant influence of the filtration velocity on the local saturation (determined via µ-CT), the number- and volume-based fractions of the identified deposited oil structures on or between adjacent fibers as well as the droplet concentrations and distributions of deposited oil droplets. It is assumed that the structure of the deposited oil formed by coalescence in the filter medium is dominated by the wetting properties of the fibers (surface tension and surface energy) and the saturation, independent of the filtration velocity. [ABSTRACT FROM AUTHOR]

Extensive oil palm plantations worldwide are dependent on insect pollination, specifically by introduced African weevils (Elaidobius spp.). The effectiveness of these weevils has been questioned following poor pollination and yield loss in Malaysia. Indigenous thrip (Thysanoptera) species, and moths (Lepidoptera) in the genus Pyroderces, may also be pollinators of oil palm, while the role of bees (Hymenoptera) and flies (Diptera) is unknown. The potential of native pollinators remains uncertain because of the almost total clearing of forest habitat from oil palm landscapes. In this study, we investigate the value of small high conservation value (HCV) forests as sources of potential native insect pollinators of oil palm in northern Sarawak. We further examine the filtering effect of oil palm-dominated landscapes on the species assemblages of six potential pollinator insect orders: Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera and Lepidoptera. Orders differed in both species composition and abundance between forest and oil palm plantations, with an average of 28.1% of species unique to oil palm. Oil palm presented a soft permeable boundary to Coleoptera, Hymenoptera and Lepidoptera. Their species richness and abundance differed little between habitats with distance, despite species turnover. In contrast, oil palm presented a harder boundary to Diptera with a decline in both species richness and abundance with distance into oil palm. The abundance of the oil palm weevil (Elaedobius kamerunicus) was low compared to the native dominants, but similar to levels displayed by native thrips that may be pollinators of oil palm. The functional diversity of well-known pollinator guilds—bees and flies—was similar in forest and oil palm, suggesting that potential pollinators may yet exist among native orders of insects. Contrary to the prevailing opinion, even small forest patches in oil palm landscapes may provide native pollinator pressure. [ABSTRACT FROM AUTHOR]

Air-oil separator is used to recover oil from the air leaving the compressor. The air-oil separator design is based on the minimum diameter of capturing oil droplet and the separation efficiency of the separator. The available air-oil separators are Cyclone, Labyrinth, wire and oil filter. In this work cyclone separator is proposed due to its higher separation efficiency for wide range of droplet size. The proposed model C1 to C6 is analysed using CFD tool and maximum separation efficiency is obtained for C4 model and minimum residence time & static pressure is obtained for C3 model. It is concluded that C3 model is finalized model due to least residence time and back pressure with acceptable separation efficiency. [ABSTRACT FROM AUTHOR]

The marine engine is a complex-structured multidisciplinary system that operates in a harsh environment involving high temperatures and pressures and gas/fluid/solid interactions. Many malfunctions and faults can occur to the marine engine and efficient condition monitoring is critical to ensure the expected performance. In this paper, a marine engine test rig is established and its process data are recorded, including various temperatures and pressures. Two data-driven models, i.e., principal component analysis and the sparse autoencoder, and a physics-based model are applied to the marine engine for two classic faults, i.e., lubrication oil filter blocking and cylinder leakage. Comparative studies and discussions are conducted regarding their performance in terms of anomaly detection and fault isolation. The data points collected for the filter blocking fault are generally two times higher than the fault thresholds set by the data-driven models. In the physics-based model, it is observed that the lubrication oil pressure falls from the predicted 3.2–3.8 bar to around 2.3 bar. For the cylinder leakage fault, the fault test data are nearly four times higher than the thresholds in the data-driven models. The exhaust gas temperature of the leaked cylinder falls from an estimated 150–200 °C to about 100 °C. The transferability and interpretability of these models are finally discussed. The findings of the present study offer insights into the two types of models and can provide guidance for the effective condition monitoring of marine engines. [ABSTRACT FROM AUTHOR]

Wind turbines have improved in terms of reliability over the past ten years, but they still experience crucial and expensive tribological issues that shorten their intended lifespans. Most turbines require significant repairs or complete replacements of the tribo components in the 5- to 7-year range. The pricey gearboxes have high repair rates, which greatly raises the operating costs for wind turbines and the cost of wind energy. Currently, various bearings in the turbine are lubricated by automatic lubrication systems with the necessary oil filters to ensure cleanliness. The commonly used lubrication methods for wind turbine bearings are centralized lubrication, oil-air lubrication, oil mist lubrication, and oil bath lubrication. There are similarities between wind turbines and spacecraft-moving mechanical systems. Most spacecraft are designed to work for decades in a remote environment without periodic maintenance. Spacecraft use efficient lubrication systems for their moving mechanical systems to provide the required lubricant to the bearings for the required life. Depending on the lubrication requirements, proven active and passive lubrication systems are employed in spacecraft. This paper reviews the lubrication issues of the wind turbine in comparison with the spacecraft and proposes a few lubrication systems that are successfully performing in spacecraft, intending to improve the reliability of wind turbine tribo-systems. [ABSTRACT FROM AUTHOR]

Unfiltered olive oils (UO) have gained popularity in the global market, but they lose their quality characteristics faster than filtered oils (FO). In this work, refrigeration and freezing temperatures were explored to maintain UO quality features during storage. A full factorial design was applied to an UO and to the same oil after filtration to evaluate the effect of storage temperature (room temperature, 4 °C and –20 °C) and freezing speed (slow-freezing, in the freezer at −20 °C and fast-freezing, in a bath of liquid nitrogen). Official quality parameters, polar and nonpolar phenolic compounds, oxidative stability index, volatile compounds and descriptive sensory profile were measured periodically over 24 months of storage in the dark. Storage temperature influenced the quality of both UO and FO, but in different ways. At non-freezing temperature, UO experienced a severe decrease in its sensory quality compared to FO, mainly due to the hydrolysis of secoiridoids and degradation of the volatile fraction, but storage at −20 °C allowed to effectively preserve UO quality traits, thus resulting as a suitable strategy to increase the shelf-life of UO to satisfy the demand of consumers for this particular product. The results showed that slow-freezing was the most appropriate method for freezing. [ABSTRACT FROM AUTHOR]

Oil mist coalescence and filtering are extensively used in the fields of natural gas purification and chemical production. However, it remains technically challenging to capture high-concentration, small-sized, oil mist droplets under complex industrial field conditions. To solve this problem, three novel high-efficiency coalescence filter cartridges are proposed, which have improved filter material arrangements. The filtering performance of the cartridges was evaluated in the laboratory and at a natural gas pipeline pressure station under different working conditions to understand the mechanism by which high-concentration small-sized droplets are captured. According to the laboratory results, the filtration efficiency for droplets> 0.2 µm can reach 99.99% if the first layer in the cartridge has a small pore size (1.5 µm). The use of a filtering material with a large pore size can reduce the pressure drop. An arrangement of layers with increasing pore sizes can significantly improve the quality factor of the cartridges and decrease secondary entrainment. In the field test, the size distributions of the oil mist under compressor "hot standby" and operating conditions were gained for the first time. The median size of oil mist droplets was 1.2 µm during hot standby and 0.5 µm during operation. Under both compressor modes, the downstream oil mist concentrations of the proposed cartridges were> 95% lower than that of an existing commercial cartridge once filtering reached a steady state. In a long-cycle test under field conditions, the proposed cartridges showed more stable filtering performance than the existing product, with the filtration efficiency being about 40% higher after 15 days. Moreover, the oil mist coalescence mechanism was determined by microscopic characterization of liquid channels. • An improved filter cartridge for oil mist separators was proposed. • An arrangement of layers with increasing pore sizes can significantly improve the quality factor and decrease secondary entrainment. • The proposed cartridges showed more stable filtering performance than the existing product. • The oil mist coalescence mechanism was determined by microscopic characterization of liquid channels. [ABSTRACT FROM AUTHOR]

Electricity distribution companies are in-charge-of supplying stable electric energy to urban customers over a wide geographical area. In these distribution networks, large number of Distribution-Transformers (DTs) are installed on towers or in electric-rooms with the ratings below 1000 kVA, which are the most important assets of distribution companies. Periodic maintenance and test services are not economically feasible for all in-operation transformers. Hence, estimating the remaining useful life and scheduling the maintenance times of DTs are of great technical and economic importance. An analytical approach is presented in this paper for predicting lifetime of DTs based on degree of polymerization. An appropriate Machine-Learning (ML) algorithm trained by measured data is selected for forecasting driven load according to the ambient temperature and humidity and day-hour schedules. The relation of Hot-Spot-Temperature in IEC60076∼7 is modified based on the measured data for accounting unbalanced-loading. Neutral-current is predicted using a trained ML-model. Another approach is proposed for determining times of oil filtering services aiming to minimize the maintenance cost and maximizing the remaining life. The proposed lifetime estimation method is validated by comparing its results with the damaged DT data of a sample network chosen as the case studies for this research, i.e., Bushehr province, Iran. [ABSTRACT FROM AUTHOR]

In order to improve the filtering effect of vacuum oil purifier, the author proposes the research and application of high-efficiency compound vacuum oil-gas separation technology based on electric ultra-high voltage transformer integrated oil purifier. The author studies under the condition of constant oil temperature and flow rate, the effect of vacuum degree on the filtering effect of transformer oil vacuum oil filter. Using the research results, a frequency conversion automatic vacuum oil filter is designed, which makes the processing process have the characteristics of simple operation, high degree of automation, and high work efficiency. The test results show that if the transformer oil processed by the variable frequency automatic vacuum oil purifier is new oil, its water content is less than 45 mg/kg and the gas content is less than 12%; when the breakdown voltage is greater than 25 kV, the transformer oil index can meet the following requirements after the equipment is filtered for one cycle: breakdown voltage ≥75 kV; water content ≤5 mg/kg; and gas content ≤0.1% (volume ratio). After one cycle (after 100 min), the variable frequency automatic (three-stage) vacuum oil filter can greatly shorten the time of transformer oil circulating and filtering. Conclusion. The designed frequency conversion automatic vacuum oil purifier is obviously better than other transformer oil vacuum oil purifiers. [ABSTRACT FROM AUTHOR]

In the shadow of the oil prices, there is a need to focus on efficient and economical oil cleaning solutions. In this research study, experimental tests are carried out to evaluate the effect of nozzle position on the performance of a selfrotating centrifugal oil filter (SCOF). The nozzle size, location, and process parameters were designed for determining the rotating speed, stability, and performance of SCOF. The performance, quality, and cost were considered as the most influential parameters in the design of SCOF. Three nozzles were mounted at the top of the rotor with center distances of 33 mm, 46.5 mm, and 58.5 mm. As it is pressure-driven, it does not require any electric motor or prime mover, which conserves resources, saves cost, and helps to preserve the environment. The optimized SCOF was characterized for different oil samples for viscosity, filtration efficiency, and total base number (TBN). It was observed that the higher speed of the rotor induces a high centrifugal force which, when overcomes the viscous force of oil it cleans less than 6 µm particles. The filtration efficiency, viscosity, TBN, and stability were significantly enhanced by changes in nozzle design and process parameters in the system. [ABSTRACT FROM AUTHOR]

The presence of oil mists constitutes a significant hazard to both, human health and the environment. In industrial applications, the effective separation of these mists typically relies on the utilization of multi-layer nonwoven coalescence filters. The underlying mechanisms governing droplet deposition, liquid transport within the filter matrix, and the evolution of the overall differential pressure have been extensively documented in the existing literature. However, limited and contradictory information is currently available regarding the impact of deposited liquid structures under varying saturation levels on the separation efficiency of coalescence filters. In this study, the influence of an increased liquid saturation at different filtration velocities on the fractional and total separation efficiency of thin porous non-woven fiber layers comparable to the first fiber layers of the first filter layer of commercially utilized coalescence filters are evaluated. As the oil load increases to a saturation of S ≤ 0.4, the total separation efficiency (number-based) decreases, for all investigated filtration velocities. In addition, a shift of the most penetrating particle size (MPPS) to smaller droplet sizes and a decrease of the MPPS efficiency is observed. This decrease is attributed to a higher interstitial velocity resulting from the accumulation of liquid within the filter matrix, leading to a lower fractional separation efficiency in the diffusion regime. However, at saturation levels S ≥ 0.6, the separation efficiency (meaning both, fractional and total separation efficiency) begins to increase due to the formation of partial oil films, leading to a blockage of void space. These films significantly enhance inertial separation. At the highest investigated saturations (S = 0.8), the highest separation efficiencies due to a nearly complete coverage of the filter layers by an oil film are observed. The film formation is confirmed through backlit images of the oil-loaded filter material. Furthermore, an increase of the MPPS efficiency for a saturation of S = 0.8 with increasing filtration velocity due to increased diffusional separation is recorded, which cannot yet conclusively answered by the authors. Additionally, the differential pressure across the fiber sheets is presented, revealing a more pronounced influence of the oil film on the differential pressure at increasing filtration velocities. • Experimental procedure to determine separation efficiencies of thin fiber layers. • Separation efficiency measurements at different saturations and flow velocities. • MPPS shifts with increasing liquid loading and different flow velocities. • Differential pressure evolution of fiber sheets during interrupted liquid loading. [ABSTRACT FROM AUTHOR]

Pressing is a common method to extract oil from oilseeds. In this method, no additives are added to the oil. The oil obtained using this method has impurities that make the color cloudy and reduce its shelf life. So, it is necessary to separate these impurities to increase the quality. In order to separate impurities from oil, a set including: pump, filter, flow control valve, pressure control valve and tank was designed and built. In this research, sesame oil was purified using a linen filter, and the compressibility of the cake and the effect of temperature and pressure on the efficiency of the filter were investigated. The compressibility coefficient for the cake in the linen filter was equal to 0.13, which shows that the porosity of the cake is relatively low. Variance analysis of linen filter efficiency data showed that temperature and pressure have no significant effect on the separation efficiency of this filter and the average separation efficiency of this filter was 76%, also temperature and pressure in the selected ranges did not affect the filter separation efficiency. [ABSTRACT FROM AUTHOR]

In the last decade, the demand for edible niche oils has increased. Therefore, the aim of this study was to characterize the seeds hemp (Cannabis sativa L.) varieties: 'Finola' (FIN-314)', 'Earlina 8FC', and 'Secuieni Jubileu', and cold and hot pressed oils were prepared from each seed. The seeds were examined for moisture content, granulometric distribution, bulk density, and fat content. Seeds were pressed without and with preconditioning (60 °C), and oil yield and pressing time were recorded. The oil was filtered through cellulose membranes. Oil–water content, oil color, fatty acid profile, and sterol content were studied. From the study conducted, there are significant differences in the parameters of oil recovery and its quality compared to 'Finola' seed oil, which is widely reported in the literature. 'Finola' oil yield was the lowest, with an average of 79% compared to 'Earlina' (82%) and 'S. Jubileu' (84%). All oil samples contained a comparable amount of sterols, with campesterol (0.32 mg/g), β-sitosterol (1.3 mg/g) and Δ5-avenasterol (0.15 mg/g) predominating. From the organoleptic evaluation, it was evident that both varieties hemp oils and marc ('Earlina' and 'S. Jubileu') were not bitter like the "Finola" oil and marc. More detailed studies in this direction have to be undertaken. [ABSTRACT FROM AUTHOR]

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The fiscal policies of OPEC + member countries are intricately linked to the fluctuations in oil prices. Through rigorous fiscal consolidation efforts, certain OPEC + nations have fortified their ability to absorb these price shocks. In our study, we introduced a range of cyclical oil price shocks by employing both HP and Hamilton filters. To ensure the robustness of our analysis, we adopted a Panel VAR approach under system GMM framework, coupled with Helmert Transformation and common correlation variables. These methodological choices effectively addressed issues related to endogeneity, heterogeneity, and cross-sectional bias in our empirical estimation. Our research uncovered that cyclical oil price shocks have an immediate, positive impact on fiscal stance, albeit with diminishing effects in the medium to long term. Conversely, gradual oil price trends displayed insignificant influence on fiscal policy. Given the considerable economic disparities among OPEC + countries, we applied a dynamic common correlation analysis within a mean group framework to disentangle the effects of cyclical shocks from fiscal responses. Our findings highlight that, among OPEC + members, Gabon, Iraq, Russia, Saudi Arabia, the UAE, and Kazakhstan are particularly well-positioned to leverage cyclical oil price shocks. These empirical results hold crucial implications for policy formulation within the OPEC + alliance. • OPEC + fiscal policies linked to oil price fluctuations. • This study employed HP and Hamilton filters for oil price cyclical shocks. • Adopted Panel VAR with system GMM and Helmert Transformation. • Cyclical shocks have a short-term positive fiscal impact. [ABSTRACT FROM AUTHOR]

With increasing automobiles in the past decade, more and more discarded air filters (DAFs) have caused severe environmental pollution due to automobile maintenance. We proposed an efficient and simple method for preparing superhydrophobic/superoleophilicity air filter for oil/water sepa- ration to solve this problem. The DAFs were functionalized by polydimethylsiloxane (PDMS) and titanium dioxide nanoparticles to enhance its hydrophobicity and oleophilicity. The morphological study showed that the use of PDMS as a binder changed the surface structure of the coatings sig- nificantly. Oil/water separation experiments revealed that DAFs could separate various oils with separation efficiencies exceeding 99%. Importantly, Experiments have shown that the superhydro- phobic/oleophilic air filter cartridge maintains a high separation efficiency (>96%) after at least ten filter cycles under oil-water mixtures with alkaline, acidic, and saline solutions. The superoleopho- bicity of DAFs was maintained in solutions of alkaline, acidic, and saline solutions for at least 72 h, indicating good durability and stability. More importantly, the DAFs not only removes oil from oily wastewater (such as in tanker leaks) but also realizes secondary use. [ABSTRACT FROM AUTHOR]

Engine emissions can be reduced by performing suitable modifications to the oil filter. Biomass medium served as the replacement for the standard paper fibres, which are used in common oil filters. The experimental analysis of 4 emission elements showed a moderate increase in the case of 2 emission characteristics, whereby a 10% increase in monoxide was present, and also, an increase of 2.5% of nitrogen oxides was observed. Further, there was a significant reduction of 2 other emission elements, namely the unburned hydrocarbons decreased by 61%, and the amount of particulate matter was reduced by 18%. Measured engine power increased by 1.2% using the modified oil filter, which proves the success of this filter. There was a decrease in oil pressure as well, the value dropped by 0.5 bar during the whole period of the measuring process. [ABSTRACT FROM AUTHOR]

With the extensive use of internal combustion engines, the large volume of lubricant consumption has become an urgent problem. In this study, a new adsorbent of modified sawdust (MS) was used to clean the waste diesel engine lubricant and prepared into a pure biomass oil filter (PBF) for the actual operation of buses. The characterization results of sawdust showed that the crystallinity index of MS enhanced 19.26%, and MS had smoother morphology, obvious pores than raw sawdust (RS). In on‐road tests, both total acid number (1 mg KOH·g−1) and total base number (9 mg KOH·g−1) were within the permitted range of the standard, and the kinematic viscosity showed a decreasing trend. In addition, the concentration of metals and insoluble colloids (<0.2%) in the lubricant was far below the oil change limit, which made the oil drain interval of the two vehicles extended from 15 000 km (recommended by manufacture) to 60 500 and 71 500 km, respectively. Conclusively, it is believed that PBF is efficient to alleviate lubricant deterioration and prolong the oil drain interval. [ABSTRACT FROM AUTHOR]

The reuse of waste cigarette filters is helpful to save resources and protect environment, and cellulose based functional materials can be applied in wastewater treatment due to the high porosity. Therefore, a novel kind of cellulose foams were fabricated by using waste cigarette filters and polyvinyl alcohol via a lyophilization technology and hydrophobicity modification in this work. As‐prepared foams possessed an ultra‐low density and high specific surface area (up to 40 m2 g−1). After the hydrophobicity modification, the cellulose foam exhibited a water contact angle of 91.9° and 126.2° on external surface and cross section, which showed a superior oil adsorption capacity of 14 g g−1. These developed cellulose foams have a low cost, good hydrophobicity and high adsorption capacity for oil as a promising absorbent, realizing the conversion of waste into high‐value products successfully. [ABSTRACT FROM AUTHOR]

Hydraulic systems are extensively used in industries. However, these systems must be free of contaminants to ensure their durability. When the contaminants entering the system are not removed with a suitable filter, sensitive parts such as pumps, motors, and actuators would be damaged. Therefore, hydraulic filters are critical elements in hydraulic systems. In this study, the flow and pressure drop in hydraulic filters were investigated experimentally and numerically. Although the main function of this device is to filter oil, it has many other functions in the system. Experiments were performed at eight Reynolds numbers in the range of 1250 ‒ 2350 at a constant viscosity. In the experiments, the pressure between the inlet and outlet of the filter was measured differently. The numerical results were used for detailed analysis of the flow after experimental verification. The analyses were performed using eight Reynolds numbers at laminar boundaries to examine the flow in the hydraulic filter. The results show that all surface areas of the filter element are not used homogeneously for fluid passage. The resultant pressure drop is due to the Dean vortex formed at the outlet of the hydraulic filter. The findings of this study can help better understand the flow recirculation regions that produce pressure drops and contaminant accumulation regions throughout a hydraulic filter from the inlet to the outlet of the flow path. [ABSTRACT FROM AUTHOR]

Nowadays, finding an efficient way to treatment oil spill and oily wastewater emission has attracted much attention all over the world. In this work, we fabricated a superhydrophobic coating (humic acid grafted by octadecylamine) with a simple method, and sprayed this coating on different structures which apply for self-cleaning, collect oil, and filter oil/water mixtures. In addition, silane-modified polymer sealant was used to strengthen the adhesive attraction between coating and structures. The coated mesh exhibited excellent superhydrophobicity (water contact angle of 153.14°) and superolephilicity (oil contact angle near 0°). Moreover, the coated mesh displayed outstanding performance in oil/water separation with huge oil flux about 16633.9 L h−1 m−2, high separating efficiency more than 95%, and good reusability (more than 10 cycles). Furthermore, the pore size of the coated mesh could regulate by changing the cycle of coated process, and the micro pore size of mesh could realize water-in-oil emulsions separation. To sum up, these merits of the superhydrophobic humic acid grafted by octadecylamine coating displayed great potential for effective oil/water separation. [ABSTRACT FROM AUTHOR]

Treatment of the filter cake layer after drilling is essential for better cement integrity and to retain the original reservoir permeability. Compared to water-based filter cake, oil-based mud filter cake removal is more sophisticated as oil encloses the filter cake's particles. Therefore, oil-based mud clean-up requires wettability alteration additives (mutual solvents and/or surfactants) for permitting acid/filter cake reaction. With an appropriate acid, microemulsions were reported to be very efficient in cleaning oil-based filter cakes, due to their low interfacial tension and high acid solubility. The objective of this paper is to provide an overview of the different techniques and treatment solutions utilized in oil-based filter cake clean-up. Furthermore, a synopsis of the various treatments for drilling fluids densified with different weighting materials is presented. Subsequently, the research limitations and opportunities have been highlighted for future work. In the light of the review that has been presented in this paper, it's recommended to conduct further investigation on some areas related to filter cake removal. The removal of filter cake formed from weighting materials other than barite, calcium carbonate, ilmenite, and manganese tetroxide needs to be investigated thoroughly. Additionally, the overall efficiency of oil-based mud removal needs to be studied under wide ranges of temperature, salinity, and pH. The utilization of surfactant-free microemulsions in filter cake treatment could also be investigated. [ABSTRACT FROM AUTHOR]