Heated Oil Research Articles

Self-Propulsion of Boiling Droplets on Thin Heated Oil Films.

We report on the self-propulsion of boiling droplets which, despite their contact with viscous, immiscible oil films, attain high velocities comparable to those of levitating Leidenfrost droplets. Experiments and model reveal that droplet propulsion originates from a coupling between seemingly disparate short and long timescale phenomena due to microsecond fluctuations induced by boiling events at the droplet-oil interface. This interplay of phenomena leads to continuous asymmetric vapor release and momentum transfer for high droplet velocities.

An Efficient Global Optimization Algorithm for Heated Oil Pipeline Problems

It is a crucial problem how to heat oil and save running cost for crude oil transport. This paper strictly formulates a steady-state heated oil pipeline operation problem as an explicit mixed integ...

Feeding heat-oxidized oil to dairy cows affects milk fat nutritional quality

Heating oil and oilseeds results in oxidation products that affect ruminal biohydrogenation of polyunsaturated fatty acids, altering milk fatty acids profile, and could be transferred to milk. An experiment was conducted to investigate the effects of oil heating on rumen and milk fatty acids profile and the transfer of oxidation products to milk. Sunflower oil was heated at 150°C for 15 h and given to lactating dairy cows in a 2×2 arrangement: two groups of two cows, equipped with a ruminal cannula and receiving two diets (containing either heated or unheated oil) during two experimental periods. Oil heating generated hydroperoxides and/or hydroxyacids and aldehydes, in particular trans-2,trans-4-decadienal. In milk, heated oil only significantly decreased trans-11-C18:1 and cis-9,trans-11-CLA percentage compared to non-heated oil, and slightly increased cis-9,cis-12-C18:2 percentage, which was probably linked to an inhibition of the ruminal Δ12 isomerase by oxidative products in the rumen. However, feeding highly oxidized oil did not result in the appearance of hydroperoxides or hydroxyacids in milk and did not increase milk aldehydes content.

Fire hazards of introducing water and ice into hot oil in open kitchen

The fire hazard of heating oil in a pan using an induction cooker under various scenarios will be studied in this article. Experiments were carried out in a mock-up kitchen on introducing water or ice to a heated oil pan at temperature below and above the auto-ignition temperature. A total of six groups of flaming conditions were conducted under varying oil depths and quantity of water or ice added. The cooking oil was heated until it ignited and was allowed to burn freely for a period of time to maintain flame over the oil surface in all tests except one. On adding water or ice to the flaming oil, vapor explosion accompanied with a big fire was observed. In another group of tests, water or ice was added to the oil without flame. In these tests, flames were not observed. Gray fog of steam and oil droplets was generated.

Experimental Study of Deposits Removal in Thermal Desalination Plants by the Thermal Shock Technique

Deposition of salts on heat transfer surfaces in thermal desalination plants can lead to operational failure. Scale removal can occur by applying a thermal shock, which is a sudden decrease in the heating process. The difference in thermal expansion between the heat transfer surface and the deposit layer plays a key role in the thermal shock process. The objective of this research is to determine experimentally the minimum temperature of the heating surface in desalination units, such that the thermal shock is still applicable. The minimum heating temperature is important for minimization of heat losses. An experimental setup has been designed and developed, and it consists of an oil tank in which oil is heated by electrical heaters. The heated oil is circulated by a gear pump to the steam generator, which contains the water to be desalinated, that is, a CaSO4 solution, at atmospheric pressure. The water is heated and converted into steam by the hot oil leaving the salts behind, that is, the fouling layer, on the tubes of the steam generator. A thermal shock is applied when the asymptotic behavior is approached, such that the flow of the hot oil is suddenly stopped for a short period of time before resuming it again. The minimum heating temperature has been determined for two types of tubes: stainless steel and copper, and at a salt concentration of 2 g/L. The minimum heating oil temperature that allows the applicability of the thermal shock is 130°C when using copper tubes, and 140°C for stainless-steel tubes.

Investigation on Crude and High-Temperature Heated Coffee Oil by ATR-FTIR Spectroscopy along with Antioxidant and Antimicrobial Properties.

The coffee oil has a promising potential to be used in food industry, but an efficient use, especially in products that required high-temperature heating, depends on its chemical composition and the changes induced by processing. Since there is little information on this topic, the aim of our study was to investigate the crude green and roasted coffee oil (GCO, RCO) and heated (HGCO, HRCO) for 1 h at 200°C, by Fourier Transform Infrared (FTIR) spectroscopy and in terms of antioxidant and antimicrobial properties. The results of FTIR spectroscopy revealed that no statistically significant differences (one-way ANOVA, p>0.05) in the oxidative status of GCO and RCO were found. The coffee oils heating induced significant spectral changes in the regions 3100–3600 cm–1, 2800–3050 cm–1 and 1680–1780 cm–1 proved by the differences in the absorbance ratios A 3009 cm−1/A 2922 cm−1, A 3009 cm−1/A 2853 cm−1, A 3009 cm−1/A 1744 cm−1, A 1744 cm−1/A 2922 cm−1. These alterations were related to the reduction of the unsaturation degree due to primary and secondary oxidation processes of the lipid fraction. The radical scavenging ability of oils investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay revealed that the IC50 value of GCO was significantly lower than of RCO (p<0.05). The IC50 values of crude coffee oils were lower than those of heated samples. The antioxidant activity of oils was attributed to both antioxidant compounds with free-radical scavenging capacity and to lipids oxidation products generated by heating. In the first 6 h of incubation, the inhibitory activity of crude oils against E. coli and E. faecalis was not significantly different to the control (p>0.05). Also, HGCO and HRCO showed significantly different inhibitory potential related to the control (p<0.05). The heating induced statistically significant decreases in the effectiveness of coffee oils against the tested bacteria. GCO proved to be the most effective among investigated coffee oils against the tested bacteria.

The Establishment of Exergy Consumption Evaluation Index in Heated Oil Pipeline Transportation

The exergy consumption during the transportation of heated oil includes four items: valid and invalid pressure exergy consumption, valid and invalid heat exergy consumption. These four parts are taken as the same loss in traditional evaluation systems of pipeline energy consumption, which somewhat hinders the further energy-conservation study. So establishing a scientific exergy consumption evaluation system is an important basis work of energy efficiency management. Based on the index system of energy efficiency for pipeline proposed by predecessors, the meaning of energy quality for exergy and the categories of exergy flow, the energy consumption index set of exergy transfer is set up in this article. Moreover, by computing exergy consumption index of exergy transfer for an oil pipeline in Daqing Oilfield, a part of representative indexes are selected by analyzing the obtained data with correlation coefficient method. Finally, the exergy consumption evaluation system is constructed.

Heated Oil Pipeline Shutdown and Restart Simulation Software Development Using VB and MATLAB Hybrid Programming

Heated Oil Pipeline Shutdown and Restart Simulation Software Development Using VB and MATLAB Hybrid Programming

Research of Heated Oil Pipeline Shutdown and Restart Process Based on VB and MATLAB

During the operation of a heated oil transportation pipeline, the shutdown was caused by some pipeline accidents and repairing. In order to ensure the safety operation of the pipeline, determine the temperature drop and restart pressure was needed at different shutdown is important. This paper builds the heated oil pipeline temperature drop model after shutdown based on the unsteady heat transfer theory and restart model based on fluid transient flow theory. In order to solve the models, MATLAB is adopted a code for the models solving program. VB and MATLAB hybrid programming method which is on the basis of COM technical is utilized to develop a friendly man-machine interface for the heated oil pipeline shutdown and restart simulation software. The practical application shows using of VB and MATLAB hybrid programming method can reduce the work of algorithm developing and enhance the reliability of heated oil pipeline shutdown and restart simulation software.

Cytotoxic Compounds Generated in Heated Oil and Assimilation of Oil in Wistar Rats

We have previously suggested that gluten binds with decomposition products from thermally oxidized oil during frying, and that low-molecular-weight compounds bound to browned gluten damage the liver in rats. Ten-week-old male Wistar rats were fed for 11 weeks ad libitum a diet containing 7 wt% fresh frying oil and 0.1 wt% gluten heated in/without oil at 180 degrees C for 10 h. Feces collected weekly and serum were subjected to lipid and hematological analyses, respectively. Values obtained in the analyses did not differ from those of the control group. The results show that thermally processed gluten does not influence the digestion, absorption, metabolism, and growth of rats, regardless of the cytotoxic low-molecular-weight compounds, and that ingested fresh oil was assimilated normally. Together with the previous results, the odor of thermally processed gluten stimulated the rats' appetite, and completely assimilable fresh oil and cytotoxic low-molecular-weight compounds bound to gluten were ingested, and thus organ damage and rapid body weight increase were observed. As commercial deep-fried products are often made with repeatedly used oil with periodically added fresh oil, similar to the present experimental diet, obesity and organ damage may also occur in humans.

Clastogenic and cytotoxic effects of lipid peroxidation products generated in culinary oils submitted to thermal stress

In rats, the administration of oil submitted to high temperatures is teratogenic. To understand the mechanisms involved, the clastogenic and cytotoxic effects were studied respectively in lymphocytes, hepatocytes (HepG2) and in human umbilical vein endothelial cells (HUVEC) cultured with a water extract obtained from heated oil (HO). In lymphocytes incubated with HO containing 0.075 or 0.15 μM of thiobarbituric reacting substances, the rate of chromosomal breakage was 18.4% and 23.1%, compared to 8.7% and 6.6%, or 8.1% and 9.2%, respectively in lymphocytes incubated with the same volume of a water extract from non-heated oil (NHO) or distilled water (DW). In HepG2 or HUVEC cells, the cytotoxic properties of the HO were dose dependent, the cytotoxicity beginning at concentrations as low as 0.25 μM. In contrast, the same volume of NHO or DW was non-toxic for these cells. The results obtained show that a water extract obtained from heated oil is clastogenic and, in higher doses, cytotoxic.

Transesterification of heated rapeseed oil for extending diesel fuel

AbstractFatty acid methyl esters are well established as an alternative fuel called “biodiesel.” For economic reasons, used frying oil is an interesting alternative feedstock for biodiesel production. The chemical changes that occur during heating of rapeseed oil, especially the formation of polymers, were investigated. Heated rapeseed oil samples were transesterified with methanol and analyzed by size‐exclusion chromatography. During heating, the amount of polymers in the starting oil increased up to 15 wt%, but only up to 5 wt% in the transesterified samples. So during transesterification, dimeric and trimeric triglycerides in the starting oil were mainly converted into monomeric and dimeric fatty acid methyl esters. The amount of polymeric fatty acid methyl esters had a negative influence on fuel characteristics. After 6 h of heating, the amount of Conradson carbon residue and after 16 h the viscosity exceeded that of the existing specifications for biodiesel. Therefore, the amount of polymers in waste oil is a good indicator for the suitability for biodiesel production.

Heated fats. Part 3. Biological effect and effect of heating and tempering oils on fatty acid composition of liver, heart and serum lipids of rats

The study deals with the biological effect caused by changes in fats during heating. The study includes feeding experiments and extraction of serum, liver, and heart from the animals tested. The biological study reveals that animals fed heated oil showed retardation of growth, poor efficiencies, rough, greasy mottled coats, and shortened life span.

Erratum for “Soil-Pipe Interaction of Heated Oil Pipelines”

Erratum for “Soil-Pipe Interaction of Heated Oil Pipelines”

Soil-Pipe Interaction of Heated Oil Pipelines

A study is presented analyzing the distress frequently encountered in buried heated oil pipelines due to the expansion and contraction producing soil-pipe interface shear and cyclic movements. This movement can damage the coating of the pipe and result in corrosion failure. The magnitude of the cyclic shear stress and movement depends on temperatures, soil properties, and pipeline design items such as the length of casing, bend, and straight pipe sections. Two important factors are the coefficient of horizontal subgrade reaction and the soil-pipe interface shear parameter. The interface shear parameter is unique to the heated pipeline problem and can serve as a coating performance and selection criteria. Methods to calculate pipe movements and ways to restrain such movements are analyzed. Actual field measurements of a heated oil pipeline are compared with theoretical calculations.

The Vapor from Heated Edible Oil and Effects of Its Inhalation on the Circulatory and Respiratory Systems in Rabbits

The inhalation toxicities of vapor from heated food oil, especially on circulatory and respiratory systems were studied in rabbits.1) Inhalation of the vapor of frying edible oil caused marked inhibitions of respiration and heart rate, and a slight elevation in blood pressure. Inhalation of the vapor of bubbling edible oil caused similar effects.2) Acrolein, carbon dioxied, ethylene and other many saturated hydrocarbones were found in the vapor from heated oil by gas chromatography. Among inhaled ethane, pentane and acrolein, only acrolein showed the same effects as those of the vapor.3) The effects of the vapor on rabbits vanished with the removal of acrolein from the vapor, and the effects of the vapor were assumed to depend upon acrolein presented in the inhaled gas.4) Under practical cooking conditions with fresh oil, 200-400μg of acrolein was recovered from the vapor during frying about 20g of potatoes or onions, and 1.1-10.3ppm of acrolein was found at 15cm above the surface of the heating oil.

‘Heated oil’ insulation system is corrosion resistant

A British concern has developed a new and more economical method of insulating and protecting heated oil lines which could lead to a significant increase in the use of long distance pipelines for transporting high viscosity petroleum products, both here and abroad.

Failure to Produce Neoplasms in Rats by Feeding Heated Wheat-Germ Oil

Failure to Produce Neoplasms in Rats by Feeding Heated Wheat-Germ Oil

Failure to Produce Neoplasms in Rats by Feeding Heated Wheat-Germ Oil

Failure to Produce Neoplasms in Rats by Feeding Heated Wheat-Germ Oil

Cleaning Oil Wells by Heated Oil

There are over 200,000 oil wells in the United States that average less thana barrel of oil a day. Many of these wells are old - 25 years and over - yetthey penetrate and give access to unmined reserves of great potential value.The leading men in the industry in recent years have regarded as inevitable animprovement in producing methods by which a more satisfactory recovery could behad. Conditions in Settled Fields The rock pressure in settled fields has become practically nil, the "paysand" is fine-grained with porosities of capillary size, the rocktemperature is such that the oil is thick and viscous, the capillary resistancealmost equals the force of gravity and it is a wonder that any oil at allreaches the well. The average spacing of wells is about one well to eight acres. This is about 600 ft. apart. The sand immediately around the bore of the well, which hasacted as a strainer for all the oil produced from the eight acres, in thecourse of time becomes clogged up by the heavy compounds in the oil passingthrough it. If there is a flow or tendency of movement of the oil in thestratum, why should the oil flow through this small clogged area into the well? Still with the initial flush production and years of dribbling, an average of 20 per cent of the oil is recovered. Method of Cleaning Wells Most methods of cleaning oil wells have had for their objective thedeparaffining of the wells. The so-called paraffin base oils, as of Pennsylvania, leave a deposit of paraffin wax in the face of the sand andparaffin wax accumulates in the well itself and on the face of the pay sand, sensibly retarding the flow of oil. Almost no attempts have been made to cleanwells producing an asphalt base oil. All methods of cleaning, however, are beneficial and temporarily greatlyincrease the production, but they are all costly and of temporary value. The chief objection is that in every case the well must be shut down, the pumptubing and rods pulled and the treatment given. Then the well is restoredphysically to a producing condition and left to get dirty and plugged upagain.