高酸原油脱酸工艺技术研究

介绍了一种原油脱酸工艺方法。研究了温度、时间对高酸原油脱酸的影响,脱酸温度大于 260℃,脱酸反应较快。分析了高酸原油脱酸前后馏分酸值的变化,脱酸反应对130℃以上各馏分酸值降低都较多,180℃以上馏分脱酸率在80％以上。     

Deacidification of sulfur olive oil. I. Single-stage liquid-liquid extraction of miscella with ethyl alcohol

In this study, a systematic and detailed investigation on liquid-liquid extraction of sulfur olive oil miscella in hexane with aqueous ethanol solutions was performed. Optimal extraction conditions for recovery of free fatty acids (FFA) with a minor loss of neutral oil were determined in bench-scale single-stage extractions. It was concluded that, to ensure deacidification with a low triglycerides loss, it is appropriate to extract the miscella with 30% or more dilute ethanol solutions. It was also noted that under these circumstances the free fatty acid percentage extracted is not affected by increases in contents of FFA and partial glycerides of sulfur olive oil, and the solvent must be saturated with hexane before extraction. Changing the oil:hexane ratio in miscella from 1:2 to 2:1 by weight did not have any significant effect on extraction results.     

Experiments and modeling on the deacidification of agglomerates of nanoparticles in a fluidized bed

The deacidification of the fumed silica AEROSIL® 200 was studied experimentally in a batch fluidized bed in the temperature range from 250 °C to 400 °C. For a well fluidized bed, the temperature and the steam concentration in the fluidizing gas are the determining parameters for the overall rate of deacidification. If the bed is not well fluidized, e.g. because it is too shallow, or it is fluidized near the point of minimum fluidization velocity, the rate of deacidification drops because channeling and bypassing occur. The adsorption equilibrium of steam and HCl on AEROSIL® 200 was measured for a wide temperature range and the temperature dependency of the Henry coefficient for steam is given. A mathematical reactor model was developed for the adsorption and for the surface reaction on highly agglomerated nanoparticles in a fluidized bed. In applying this model to the experimental data for the deacidification, a simple kinetic rate expression could be derived for the deacidification reaction, which is otherwise not obtainable. The temperature dependency of the rate constant was also determined. All other parameters for the model can either be found through independent measurements (e.g. adsorption equilibrium or fluidizing characteristics) or in literature. The model can be used for sizing and optimizing of fluidized bed reactors in the production of fumed oxides.     

Comparison of steam and nitrogen in the physical deacidification of soybean oil

Deacidification in physical refining is one of the most sensitive steps in refining edible vegetable oils because of its large impact on the quality of the oil. The removal of volatile compounds such as FFA is accomplished at elevated temperatures and a high vacuum with a stripping gas, usually steam. The aim of this work was to verify, at the laboratory level, the advantages of using an alternative stripping gas, nitrogen, instead of steam. An ideal vapor-liquid equilibrium model (IVLE) was used to compare the stripping capacities of steam and nitrogen and to analyze the effects of various operational parameters (temperature, pressure, amount of stripping gas) on the residual acidity of the oil. There was no clear evidence that nitrogen showed a higher capacity to strip FFA than steam. The IVLE model seemed suitable to describe FFA laboratory distillation by using steam or nitrogen, provided the final residual content of FFA was not too low.     

Deacidification of olive oil by countercurrent supercritical carbon dioxide extraction: Experimental and thermodynamic modeling

Supercritical carbon dioxide was used as an extractive solvent to remove free fatty acids from cold-pressed olive oil. Crude oil of different acidity content (from 0.5 to 4.0 wt%) was extracted in a packed column at 313 K and pressures of 180, 234 and 250 bar. The group contribution equation of state was employed to simulate the separation process, representing the oil as a simple pseudo-binary oleic acid + triolein mixture. Despite the simple representation of oil composition to simulate the deacidification process, a satisfactory agreement between the experimental and calculated yields and acidity of raffinates was obtained. The thermodynamic model was employed to study a continuous countercurrent multistage extraction process which yielded a raffinate having acidity lower than 0.7 wt%, when crude olive oil with different FFA content was processed.     

高酸原油脱酸技术的研究进展

分析了常规高酸原油脱酸工艺的不足,介绍了近几年国内外对高酸原油脱酸的新工艺方法,如离子液体原油脱酸、脱酸剂技术脱酸、高温热解脱酸等方法。新技术将对原油脱酸技术的发展起到一定的推动作用,其中咪唑型阳离子脱酸具有较大的应用前景。     

The use of malolactic Oenococcus oeni (ATCC 39401) for deacidification of media containing glucose, malic acid and citric acid

 Malolactic fermentation is widely used to reduce the acidity of grape juices in wine production. However, application of the same technology to the production of wine from berries of the northern regions is not straightforward. Unlike grapes, these berries are rich in citric and malic acid while the sugar content is low. An ideal deacidification process for the northern berries would be the microbial degradation of these acids with minimal loss of sugars. Therefore, the co-metabolism of citric acid and glucose was studied under different conditions of malic acid degradation by Oenococcus oeni. At low pH values (pH <4.5) degradation of malic acid always proceeded first to completion with practically no consumption of glucose or citric acid. After the exhaustion of malic acid the degradation of both citric acid and glucose were initiated simultaneously. Following the exhaustion of malic acid and citric acid the remaining glucose remained nonfermentable. Thus, it is concluded that, by maintaining the culture in a resting state by the control of pH, selective degradation of acids can be achieved without subsequent loss of glucose. Received: 20 January 2000     

高酸值米糠油的生物精炼

通过生物精炼（酶法脱酸），大大地降低了高酸值米糠油中的游离脂肪酸含量，为高酸值米糠油的利用带来令人鼓舞的前景。     

不同方法清洗黑索今的脱酸试验研究

以黑索今-清洗液固-液体系为研究对象,通过单因素试验和正交试验,研究了磁力搅拌清洗和超声辅助清洗对黑索今脱酸清洗效果的影响,并对两种清洗方式的工艺条件进行了优化和比较。结果表明,磁力搅拌清洗工艺的脱酸效率较低,超声辅助清洗工艺与之相比清洗时间短、温度较低,清洗脱酸效果大大提高;其优化条件为超声时间70min、温度35℃、超声频率40kHz、超声功率85%,在此条件下,黑索今最终酸度达到0.006%。