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21.
新疆棉籽油含有700 mg/kg的蜡质和26%~28%的固体脂,由于新疆气温多在零度以下,棉籽油在运输、储存和销售过程中易产生固化、沉淀、发朦,影响棉籽油的外观、食用和销售。为了保持包装棉籽油透明,提高棉籽油的质量和附加值,对棉籽油进行深度分提以脱蜡脱脂。介绍了棉籽油深度分提工艺,即在15 ℃脱除蜡质,在7 ℃分提出棕榈酸甘三酯,继续降温至-10 ℃分提出棕榈酸甘二酯、棕榈酸甘一酯及其他硬脂,最终得到在低温下保持透明的棉籽液油。 相似文献
22.
Zohal Safaei Mahmoudabadi Alimorad Rashidi Mohammad Panahi 《International Journal of Hydrogen Energy》2021,46(7):5270-5285
Highly active ReS2 nanocatalysts were prepared by CVD method and characterized by XRD, BET -BJH, Raman spectroscopy, XPS, TPR, NH3-TPD, SEM, and HRTEM techniques. Catalytic activities were used in upgrading heavy crude oil using methane as hydrogen source. The results showed a significant increase in API and decrease in sulfur and nitrogen content of crude oil. RSM technique was used to investigate the interactive effects of temperature (200–400 °C), pressure (20–40 bar) and dosage of nanocatalyst (0.5–2 wt. %) on the performance of HDS reaction. The results represent that the maximum predicted HDS activity (74.375%) was estimated under the optimal conditions (400 °C, 20 bars, and 2 wt % of nanocatalyst). Also, the effect of reaction temperature, pressure and dosage of ReS2 nanorods catalyst on HDN of heavy crude oil was investigated and highest efficiency in the HDN process (93%) occurred at 400 °C and 40 bar using 2 wt % ReS2. 相似文献
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Gülsün Özyurt Ali Serhat Özkütük Yılmaz Uçar Mustafa Durmuş Yesim Ozogul 《International Journal of Food Science & Technology》2019,54(4):1081-1088
Waste or by-products contains a substantial amount of nutrients. Fish silage is an alternative way for assessment of fish discards and waste generated in the fish processing industries. The aim of the study was to evaluate the potential use of discard species (Equulites klunzingeri, marine fish and Carassius gibelio, freshwater fish) for fish silage and chemical quality of fish oil extracted from fish silages prepared with acid and fermented methods. Lipid quality of fish oils extracted from fish silages with LAB strains was evaluated in terms of thiobarbituric acid (TBA), peroxide value (PV), p-Anisidine (AV), totox values and fatty acid composition. The results showed that PV, TBA, AV and totox values of all extracted fish oils were within the acceptable limits for edible oils. Recovered fish oils from silage contained high level of polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), serving as a source of good quality fish oil for human consumption. 相似文献
25.
Marija Glisic Milan Baltic Milica Glisic Dejana Trbovic Marija Jokanovic Nenad Parunovic Mirjana Dimitrijevic Branko Suvajdzic Marija Boskovic Dragan Vasilev 《International Journal of Food Science & Technology》2019,54(3):787-797
In order to produce fermented sausages with prebiotic fibre and improved fatty acid composition, 16% of pork back fat was replaced with inulin gelled suspension (I) and inulin linseed oil gelled emulsion (IO). Physico-chemical analysis, fatty acid profiles, lipid oxidation, microbiological, textural, colour and sensory analysis were carried out. The fat content was lower in I (31.38%) and IO (35.36%) modified sausages compared to control (44.37%) (P < 0.05). IO sausages had lower SFA and MUFA and higher PUFA content with an improved n-6/n-3 ratio (2.23) (P < 0.05) and α-linolenic acid increment (5.74 g per 100 g). Reformulation led to decrease in springiness, chewiness and hardness and increase in adhesiveness of the sausages. Modified sausages had lower L* and higher a* values, while b* values of I sausages did not differ compared to control sausages. Modified sausages were acceptable regarding all sensory attributes. Lipid oxidation parameters showed higher susceptibility to oxidation and lipolysis in IO sausages. 相似文献
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Tamara Schad Natalie Preisig Wiebke Drenckhan Cosima Stubenrauch 《Journal of surfactants and detergents》2022,25(3):377-385
Liquid foams of intermediate stability have been shown to be very efficient in the cleaning of sensitive surfaces because of the synergy between imbibition and foam decay. While we quantified these mechanisms for contaminations with liquid oils in our previous work, we show here their extension to oils containing soot particles in an effort to simulate increasingly realistic contaminations. Using foams with a wide range of liquid fractions and with different stabilities, we show that the main cleaning mechanisms remain very similar, with the oil entraining the soot particles. However, we find much less efficient soot removal when the liquid channels of the foams are small enough to hinder efficient transport of the soot particles. 相似文献
29.
《Egyptian Journal of Petroleum》2021,30(4):43-51
Today, the issues related to solving the problem of finding an effective distribution of oil flows through the system of oil pipelines in order to reduce the total energy consumption are relevant. The solution to this problem is connected with selection of rational pumping modes for various technological sections of oil pipelines using modern methods of mathematical programming or new techniques for improving the energy and transport characteristics of oil.Reducing energy consumption during pumping of crude through oil trunk pipelines can be achieved by various methods. Numerous investigations in this direction are mainly carried out to save energy on separate single-line pipelines. However, due to the development of the network of trunk oil pipelines in the world over the past decades, the issues of energy efficient management of oil flows throughout the entire oil pipeline system of oil and gas enterprises become urgent.This paper analyses parameters for pipeline transport of high-viscosity and heavy oils. The article proposes a method for assessing the rheological properties of oil for further planning of pumping taking into account the preservation of oil quality and an increase in energy and transport characteristics. The proposed solutions and tasks for predicting changes in the viscosity-temperature characteristics of the flow for blends of different oil types are especially relevant in the current conditions of an increase in the share of oil production with complex rheological characteristics. Results of the presented investigations may be used for planning the measures of efficient transportation of high-viscosity and heavy oils. 相似文献
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