Bland undenatured soybean flakes by alcohol washing and flash desolventizing

The conditions for removing the beany and bitter flavor from defatted soybean meal with ethanol and isopropyl alcohol were investigated. In the presence of alcohols, soybean protein is extremely sensitive to denaturation when temperature, moisture, and residence time are increased. If protein is to be isolated in good yield and quality, retention of the original, high watersolubility is important, and denaturation must be kept to a minimum. Defatted soybean flakes were successfully debittered by countereurrent washing with aqueous alcohols on a pilot-plant scale, and the entrained solvent was recovered by flash desolventizing without excessive denaturation of protein. Effective debittering was obtained with 95 volume percentage ethanol and 91 volume percentage isopropyl alcohol whereas satisfactory flavor was not obtained with absolute ethanol. The solubility of the nitrogenous compounds in the meal product (Nitrogen Solubility Index—NSI=water-soluble nitrogen×100÷ total nitrogen) was maintained at 68 NSI, or higher, regardless of the solvent system or conditions used when starting with 80 NSI defatted flakes. Residual alcohol in the desolventized products was reduced to 1–2% with the aqueous alcohol system and to less than 1% for the absolute alcohol system. Lower residual values can be obtained by recycling the material through the desolventizing unit. The desolventizing system described is simple, low in cost, and should be useful in any process requiring the rapid removal of solvent from residual solids where heat-sensitive constituents are present.     

Flash desolventizing defatted soybean meals washed with aqueous alcohols to yield a high-protein product

A vapor-type desolventizer was developed previously at this laboratory to recover hexane and concentrated alcohols from soybean mares. The work reported in this paper extends the application of this unit to the recovery of dilute alcohols. Soybean protein meals washed with aqueous alcohols are debittered to yield a better flavored product with a significant increase in protein content. The protein of defatted meal was increased from about 50 to 70 or 75% by washing with methanol, ethanol, or isopropyl alcohol in a concentration range of 50–70%. System modifications and critical variables were investigated so as to minimize residual alcohol and to yield a free-flowing homogeneous product. Residual alcohol in the desolventized flakes was 0.25–1.0%. Facility of removal followed the order—methanol, isopropyl alcohol, and ethanol. Two-stage flash desolventization as well as the use of the more dilute alcohols resulted in lower residual alcohol content of the desolventized product. After a minimum value for residual alcohol in the flakes is reached, further removal is difficult. However, water continues to be removed so that the alcohol water ratio becomes higher with an increased vaporization force as with increased temperature. It is postulated that the alcohol is held by adsorption or hydrogen bonding. The desolventized products analyzed: protein 72–77%; Nitrogen Solubility Index 4–16; water absorption values 328–410%. The products were light-colored, granular, and free flowing. The soybean flakes extracted with methanol exhibited the best flavor. A laboratory of the Northern Utilization Research and Development Division, U.S.D.A.     

Processing methods to preserve quality and color of cottonseed flakes

Hull-free cottonseed flakes were prepared for direct solvent extraction by two passes through a pilot plant size, hot air drier set at 200 F. Moisture content was reduced to 6.5% without evidence of gossypol binding. Improved drainage characteristics resulted in better extraction. Glanded and glandless flakes which had been extracted and partially desolventized at low temperatures were heated indirectly in a batch desolventizer under vacuum to temperatures above the point of steam condensation and solvent stripped with superheated steam. Resulting available lysine and protein solubility values on the meals and flours were desirably high. The desolventization was accomplished without significant color darkening. Operated by the Texas Engineering Experiment Station for the Cotton Research Committee of Texas.     

Moisture equilibrium of wood and bark chips in superheated steam

This study relating to the steam drying of biofuels suggests that the activities of water in air (defined as relative humidity) and of water in superheated steam (defined as the ratio of the saturated pressure and the saturated pressure at the superheated temperature) are identical. The dependence of the activity in superheated steam on the equilibrium moisture content was studied in various experiments for different wood materials at constant temperatures of 140 and 160°C. The equilibrium moisture content was found to depend on the following factors: the activity of the superheated steam, the temperature and the materials used, the first of these being the most important. The experimentally determined sorption isotherms were compared with different sorption theories. The Dent model gave a good correlation with the experimental data. The sorbed water can be divided into primary water with high binding energy and secondary water with low binding energy. If biofuels are to be dried with superheated steam, an equilibrium moisture fraction of 0.05 seems to be relevant. It will probably be possible to reach this with activities in the range 0.2–0.4 for all real materials.     

Aqueous Extraction of Oil and Protein from Soybeans with Subcritical Water

Aqueous extraction using subcritical water is an environmentally friendly alternative to extracting oil and protein from oilseeds with flammable organic solvents. The effects of solids-to-liquid ratio (1:3.3–1:11.7), temperature (66–234 °C), and extraction time (13–47 min) were evaluated on the extraction of oil and protein from soybean flakes and from extruded soybeans flakes with subcritical water. A central composite design (2³) with three center points and six axial points was used. Subcritical water extractions were carried out in a 1-L high-pressure batch reactor with constant stirring (300 rpm) at 0.03–3.86 MPa. In general, oil extraction was greater for extruded soybean flakes than with soybean flakes. More complete oil extraction for extruded soybean flakes was achieved at around 150 °C and extraction was not affected by solids-to-liquid ratios over the range tested, while oil extraction from soybean flakes was more complete at 66 °C and low solids-to-liquid ratio (1:11.7). Protein extraction yields from flakes were generally greater than from extruded flakes. Protein extraction yields from extruded flakes increased as temperature increased and solids-to-liquid ratio decreased, while greater protein extraction yields from soybean flakes were achieved when using low temperatures and low solids-to-liquid ratio.     

FLASH DRYING OF FISH MEALS WITH SUPERHEATED STEAM: ISOTHERMAL PROCESS

The work considers the application of the flash drying to the moisture removal of fishmeal using superheated steam as transport medium. Heat, momentum and mass transfer equations were applied and an algorithm based on these equations was developed and solved. The model was validated using experimental data obtained in a pilot pneumatic dryer ( total length 60 m) provided with a steam jacket to maintain the superheated steam at a constant temperature. The drying time was less than 10 s to decrease the fish meals moisture content from 53.5% to 28% d.b. and in a second pass by the dryer the moisture down to 16.9% using superheated steam at It 1 ° C and 130 ° C in the jacket. The computational results are in agreement with the experimental data.     

FLASH DRYING OF FISH MEALS WITH SUPERHEATED STEAM: ISOTHERMAL PROCESS

ABSTRACT

The work considers the application of the flash drying to the moisture removal of fishmeal using superheated steam as transport medium. Heat, momentum and mass transfer equations were applied and an algorithm based on these equations was developed and solved. The model was validated using experimental data obtained in a pilot pneumatic dryer ( total length 60 m) provided with a steam jacket to maintain the superheated steam at a constant temperature. The drying time was less than 10 s to decrease the fish meals moisture content from 53.5% to 28% d.b. and in a second pass by the dryer the moisture down to 16.9% using superheated steam at It 1 ° C and 130 ° C in the jacket. The computational results are in agreement with the experimental data.     

Controllability of Product Moisture Content When Nonscreened Sawdust Is Dried in a Spouted Bed

The control of the dried product's moisture content is of importance in the production of fuel pellets. Tests have been made in air and superheated steam in a spouted bed using the outlet temperature of the drying medium as a control parameter of the dried material's moisture content. For superheated steam different settings for the inlet medium temperature are also used. In the moisture content interval of 8-17% wet base there is a linear correlation between the dried material moisture content and the outlet temperature of the drying medium. When drying nonscreened sawdust in a spouted bed it is recommendable to use the outlet temperature of the drying medium as a control parameter of the dried material moisture content. This is independent of the size of the sawdust, whether superheated steam or air is used as a drying medium.     

气提脱酚制备聚碳级双酚A工艺研究

针对传统的精馏法、结晶法及刮膜蒸发法脱酚工艺存在的诸多弊端,有必要对新的脱酚工艺进行研究,以制备超低游离酚质量分数的聚碳级双酚A。鉴于双酚A-苯酚物系高沸点、热敏性特性,文中以降膜蒸发脱除大部分苯酚、获得的粗双酚A为原料,采用向真空填料塔通入过热水蒸气进行气提的方法,研究制备超低游离酚质量分数聚碳级双酚A的脱酚工艺。研究结果表明:气提塔的操作压力、水蒸气温度和流量对脱酚效果有很大的影响。操作压力越低,组分间相对挥发度增大,脱酚效果越好。但过低的压力对脱酚效果的改善将不明显,带来的负面影响是设备投资的增加;水蒸气温度越高,塔内物料温度也随之升高,苯酚的饱和蒸汽压增大,脱酚效果越好;水蒸气流量越大,在操作压力不变的情况下,苯酚的气相分压就越低,脱酚效果越好。适宜的工艺条件是:操作压力为4.0—5.0 kPa;气提水蒸气温度185—190℃,流量为处理量的2%。     

Production of furfural from agricultural wastes by using pressurised water in a batch reactor

Agricultural wastes such as rice husks and sawdust can be used for the manufacture of chemicals including furfural and acetic acid. In the present work the conventional use of superheated steam has been replaced by the use of superheated water in the acidic hydrolysis of rice husk and sawdust. Comparable yields of furfural have been obtained by using superheated water in place of superheated steam in the same temperature and pressure range. This is an attempt to economise the heat requirement and reduce the cost of production of furfural.     

Extraction of oil from soybeans

Modern processing plants extract soyabean oil by solvent liquid transfer. Soyabeans are cleaned, cracked, dehulled and conditioned into a thin flake before they enter the extractor. Extraction is by successive, countercurrent washes of hexane solvent. The extracted flakes are then carried by a sealed conveyor to be desolventized in enclosed vessels by application of jacket and sparge steam. Hexane is removed from the oil in rising film evaporators and with final vacuum distillation. Hexane is recovered from the meal and the oil in atmospheric condensers. The complete plant installation is explosion-proof and all equipment is sealed and vapor-proof. For a good operation, soyabeans must be clean, undamaged and at the correct moisture and temperature. Parameters of the process in the plant are: tonnage, hexane loss and energy usage. Oil quality is measured in terms of free fatty acids, absence of residual hexane and crude oil color. Meal quality is determined by residual oil, moisture, protein, urease activity protein solubility and mesh size in the finished product. Innovations at modern plants include degumming of the oil, lecithin drying and blending and production of soyabean meal with high protein solubility for human consumption.     

庆45区块稠油蒸气驱生产井闪蒸预测分析

在大庆油田庆45区块稠油蒸气驱生产过程中,地层的非均质性导致局部受效层温度过高,引起井底闪蒸。根据传热学和计算流体动力学理论,建立井底温度计算模型,提出闪蒸预测方法,将计算的井底温度、压力与水饱和蒸汽临界温度-压力曲线相结合,依据井底温度和压力在临界曲线上的相对位置判断井底闪蒸情况。以庆45-22-K281井为例,进行现场测试和井底闪蒸预测。预测结果与实测结果表明,闪蒸预测方法有效,为稠油蒸气驱生产井的闪蒸防治提供依据。     

Steam stripping of lard

Conclusion The rate of steam stripping of free fatty acids from lard can be evaluated in terms of a rate·constant K defined by Equations 5 and 6. Reproducible results were realized for many different batches of leaf and prime steam lards. The effects of temperature, total pressure, and steam rate were evaluated, thus making possible the calculation of stripping rate constants on a comparable basis. Comparable values of the rate constant K have been compared for conditions with and without the use of mechanical agitation with a flat-blade mixing impeller. Use of the rotating mixing impeller showed substantial increases (30 to 50%) in the reaction rate constant, over those obtained with steam sparging without the mixer. Accordingly the use of this type mixer should result, in large savings of steam for stripping and for maintaining the necessary vacuum by the steam jet condenser. Presented at the 1952 Spring Meeting, American Oil Chemists' Society, Houston, Tex., Apr. 28–30.     

Critical processing factors in desolventizing-toasting soybean meal for feed

Even though it is well established that both underheated and overheated meals are of inferior nutritive value, comparatively little is known of the fundamental nature of the changes brought about in the protein and how these correlate with the processing conditions during toasting. In the present study we examined the interrelation of several factors in the commercial desolventizing-toasting process for toasting soybean meal and determined how these relate to protein quality of the meal. A total of 48 test runs were made in the pilot plant from two cultivars of soybeans (one high and one low in protein) that were dehulled, flaked, and defatted in a continuous extractor using hexane. The solvent-wet flakes were desolventized and toasted under a variety of conditions. In a simulation of commercial operation, independent variables such as moisture, temperature and time of toasting were mathematically converted to equations for computer fitting of the data, which were used to predict several dependent measurements. Quality of the meal was improved by increasing heating time, jacket steam pressure and moisture content. Moisture level in the toasting operation was directly affected by the hexane level in the feed material to the toaster.     

Gas-chromatographic determination of residual hexane in hexane-extracted soybean flakes

A method was developed to determine residual hexane in hexane-extracted soybean flakes by gasliquid chromatography (GLC). After residual hexane was extracted with pure isooctane, the quantity extracted was determined by GLC. Analyses were run on three different columns. Column efficiency was varied to obtain maximum speed and accuracy. An attenautor was used to amplify the low-signal output of the extracted residual hexane. Accuracy of the method was established by analyzing soybean flakes containing 0.01–7.5% added hexane. The lower limit of accuracy is approx 0.02%, and the time required for analysis is ca. one hr. Residual hexane present in other kinds of hexane-extracted oilseed flakes might also be analyzed by this method. It is probable that extraction solvents other than hexane which are infinitely soluble in isooctane can also be determined by the method proposed. Presented at AOCS Meeting, Minneapolis, 1963. No. Utiliz. Res. & Dev. Div., ARS, USDA.     

Design,construction and operation of lab scale cylindrical steam assisted gravity drainage model for heavy oil recovery

Based on a theoretical background [1,2], a lab scale cylindrical SAGD (steam assisted gravity drainage) model was designed, constructed and operated. There are six different parts in the apparatus: (1) water supplier, (2) steam generator, (3) SAGD cylindrical model, (4) cooling system, (5) constant pressure maintaining system and (6) production system. Temperature, pressure and steam injection rate were controlled by computer, and product (mixture of oil and water) was collected/separated manually. Extra heavy oil (<10 cp at 200 °C) and glass bead (diameter 1.5 mm) were mixed homogeneously for making porosity of 0.3 and applied for simulating oil sand. For obtaining optimum operation conditions of SAGD apparatus, several attempts were made. When the steam at high temperature (160–180 °C), high pressure (8–9 atm) was injected with 20–25 cc/min, cSOR (cumulative steam to oil ratio) of about 5 was obtained with oil recovery of 78.8%.     

Desolventizing-toasting of extracted soybean flakes: Development of pilot plant equipment and operational procedure

A pilot plant batch desolventizer-toaster (D-T) was designed and built with the intent of producing soybean meals of varied composition, as well as to simulate meals produced in a continuous commercial D-T unit. Trial runs were made first to determine workable loading levels, temperature control and sparge steam generation. Moisture levels after the steam sparge were influenced by the residual hexane content of defatted hexane-wet flakes reaching the D-T. Two moisture levels were used in testing the effectiveness of the toasting operations in producing flakes with low urease activity and trypsin inhibitor levels. The trial runs reported here also provide basic data for current work designed to optimize toasting procedures to produce suitable meals for ongoing animal nutrition studies.     

Carbohydrase hydrolysis of canola to enhance oil extraction with hexane

Hydrolysis of three canola cultivars with carbohydrase reduced oil extraction time and increased oil yield. The optimum pretreatment before hexane extraction of oil was flaking, autoclaving, adjustment to 30% seed moisture including 0.12% enzyme concentration (g enzyme protein/100 g flakes), and incubation for 12 hr at 50 C, followed by drying to 4% moisture. Hexane extraction was enhanced by grinding the flakes. The relative order of enzyme efficiency in enhancement of oil extraction was mixed activity enzyme >β-glucanase>pectinase>hemicellulase>cellulase. Presented at the AOCS Annual Meeting in Honolulu, HI in May 1986.     

湿法磷酸汽提法脱氟技术研究

在饲料级磷酸氢钙生产过程中,湿法磷酸中的磷氟比（五氧化二磷与氟的质量比）≥250才能符合生产要求。采用汽提法脱氟技术,研究了汽提方式、汽提时间、磷酸温度、磷酸浓度及真空度对湿法磷酸脱氟效果的影响。实验表明：采用减压脱氟,将质量分数为50%的浓磷酸加入圆底烧瓶中,加入氟含量2倍的白炭黑,将磷酸温度升高至100 ℃,真空度控制为20 kPa,脱氟1 h,可使磷酸的磷氟比达到286.97,满足饲料级磷酸氢钙对湿法磷酸的要求。     

Quality Changes of Superheated Steam–Dried Fibers from Oil Palm Empty Fruit Bunches

Conventional drying of the fibers from oil palm empty fruit bunches (EFB) using flue gas from diesel burners frequently causes browning and dust explosion. Replacing the drying medium with superheated steam is expected to improve the quality of EFB fibers as well as improve the safety of the dryer operation. In this study, the effects of steam temperature and steam velocity on the quality of steam–dried EFB fibers was investigated. The drying experiment was carried out at atmospheric pressure with steam superficial velocity in the range of 0.3 to 0.49 m s^?1 and temperature in the range of 135 to 200°C. Three quality parameters of the EFB fibers, the color, strength, and microstructure, were used to assess the changes in EFB fiber quality as a result of superheated steam drying. The color of the EFB fiber was either improved or not significantly degraded. The strength of the superheated steam–dried EFB fibers was higher than that of undried and hot air–dried EFB fibers. The microstructure of fresh undried EFB fibers as seen by scanning electron microscopy (SEM) showed the presence of round silica particles of 10–20 µm in diameter all over the EFB fiber strand, which complicates pulping and bleaching. Superheated steam drying successfully removed the silica particles from the EFB fibers at temperatures of at least 200°C and a velocity of steam of at most 0.49 m s^?1, which is better than hammering, which can only remove 88% of the silica particles. The high temperature of the superheated steam loosened the silica particles from their craters. The EFB fibers cracked and split at steam velocities at or above 0.49 m s^?1 and high superheated steam temperatures at or above 200°C and as a consequence became weaker at these conditions. The removal of silica particles by superheated steam drying makes the EFB fiber amenable to pulping and bleaching. Superheated steam drying is therefore found to improve the overall quality of EFB fibers compared to hot air drying.