Stripping Section Research Articles

Deodorizing system modification for heat recovery and steam refining of palm oil

AbstractWith continuous deodorizers of the double shell type most of the steam normally used to preheat the feedstock in the deaerating section can be saved by a modification‐the essential feature of which is the addition of a heat recovery section location between the final deodorizing section and the cooling section, by means of which heat is transferred from the hot deodorized oil to the feedstock. Consistent with the principles of the original design, no pumping or piping of hot oil outside the deodorizer is required. Continuous deodorizers of the stripping tray type can be modified for “steam refining” or “stripping” of high free fatty acid palm oil to reduce the free fatty acid palm oil to reduce the free fatty acids to 0.03% max. This is accomplished by means of additional trays in the stripping sections of the deodorizer. The capacity, sparge steam temperature, vacuum and retention time remain the same as with normal deodorization.

Thermodynamic efficiency of rectification units with stripping sections

1. An overall thermodynamic classification of various schemes for the separation of multicomponent mixtures has been made. In accordance with this classification, a unit with stripping sections, used in oil refining, is defined as a system with partially connected heat fluxes. 2. A computer calculation of various separation schemes has been made. It has been demonstrated that the thermodynamic efficiency of rectification units with stripping sections is greater than the efficiency of multicomponent units with consecutive separation of the components in two-sectional columns.

Positive parity states in 167Er

Abstract The positive parity states in 167Er are described in terms of the rotational model, where the particle-rotation coupling is taken into account. The moment of inertia, the Fermi energy and the coupling strength are determined by fitting the energies. The wave functions thus obtained are used to calculate the (d, p) stripping and (d, t) pick-up cross sections and branching ratios. The results obtained are in agreement with experimental data.

Operation of stripping sections in atmospheric-vacuum distillation units

1. A study has been made of stripping-section operation with steam injection as a control object under commercial and laboratory conditions. 2. It has been shown that, as the steam injection rate is increased, the vapor number increases, but this increase tapers off rapidly. With steam injection rates above 5–7% (of residue), the vapor number is practically constant. 3. An investigation has been made of the effect of vapor number of changes in distillation curve of a feed-stock when it is fractionated in a stripping section. 4. It has been shown that experimental relationships obtained in a laboratory model unit can be used as a basis for developing process control algorithms for fractionation in commercial stripping sections.

The optimal design of a laboratory distillation column for efficiency studies at finite reflux

A laboratory distillation column is to be set up to evaluate overall column efficiencies at finite reflux. The choice of the number of plates in each section of the column will profoundly affect the accuracy of the final results. That number of plates which minimises the errors is optimal. A general analysis of the contribution of experimental errors to errors in the final results is presented. It is applied to the evaluation of the optimal number of “theoretical” plates for the test system methycyclohexane-toluene over a range of internal reflux ratio 0·7 to 1·00 in the rectifying section and 1·00 to 1·30 in the stripping section. The author's experimental results with the above test system in a 1 1 4 in. Oldershaw column are used to provide the necessary overall efficiencies for a design calculation.

The 3/2− |532| rotational band in 155Gd

Abstract A calculation including Coriolis coupling of the low-lying negative parity Nilsson model orbitals in 155 Gd is performed. The energy of the 3/2 − |532| band head is based on the Nilsson model. A comparison between the calculated and experimental energies, the (d, p) stripping and (d, t) pick-up cross sections is used to verify the suggested perturbed energy position of the 3/2 − |532| band.

Optimization of PID Tuning Using Genetic Algorithm

Controller tuning is one of the important aspect in industry. With a good tuning method, it can ensure the quality of the process and product produce. Apart from that, it can protect the environment and help the company to reduce the cost. Genetic algorithm is one of the tuning method that increase usage and awareness in industry. Thus, the objective of this research is to compare the performance of the conventional tuning method with the performance of tuning method by using genetic algorithm can be seen. Optimization was done on stripping section of distillation column by using genetic algorithm with population size of 20, 40, 60 and 80 and comparing the result with previous optimization using Ziegler-Nichols method. The result obtain showed large improvement in the process response especially on rise time from 1.33 s to 1.31s and settling time from 4.56 to 4.46. Finally, population size of 40 deliver the fastest rise time and settling time.

Coriolis coupling analysis of the cross sections from (d, p) and (d, t) reactions

The influence of the Coriolis coupling on the (d, p) stripping and (d, t) pick-up cross sections have been studied for several nuclei in the mass region 155–171. The calculated energies, cross sections and wave functions are tabulated for 159Gd, 163Dy, 163Er, 165Er, 167Er, 169Er, 169Yb and 171Yb, where four to eight negative parity bands have been included in the calculations. The inclusion of the coupling in the calculations can in many cases improve the agreement between the experimental and theoretical results.

新しいU.S. AEC濃縮ウラン価格表

U.S. AEC has recently revised its standard table of enriching services. The new schedule of base charges for enriched and depleted uranium in the form of UF6 can be computed according to formulas in the theory of ideal cascade on the basis of taking natural uranium having on assay of 0.711w/0 235U as having a zero separative work component and on the basis of a tails assay of 0.20w/0 235U. No optimization of the size of stripping section is made in the schedule.An estimate of separative work costs and capacities of enriching facilities in UK, France and Red China is formed.

Operating lines in cascade separation of binary mixtures

AbstractThe general case of cascade operation is treated without any restriction on the value of the separation factor. Equilibrium curves are briefly discussed. These are generally a function of the cut.The equations of operating lines for both of enriching and stripping sections are derived for the general case by appropriate material balances. Also, three specific applications are presented in detail, by showing graphical constructions and discussing characteristic features for each case.

Synthesis of Dispersive Delay Characteristics by Thickness Tapering in Ultrasonic Strip Delay Lines

Tapering the thickness of a dispersive strip delay line operating in the first longitudinal mode can yield a variety of delay characteristics unobtainable with strips of uniform thickness. A strip whose thickness varies in some manner along its length may be thought of as a number of strip sections of constant thickness in series. The additive delay of these series sections can produce an over-all delay characteristic completely different in form from the delay characteristics of the individual sections. A design procedure involving the methods of linear programming has been developed which allows a unique determination of the taper required to produce a given delay function. As a basis for comparison, the delay of a strip delay line of constant thickness departs from a straight-line characteristic by 1.5% of the nominal delay over a fractional frequency bandwidth of 15%. A tapered strip line designed for the same nominal delay and the same delay slope departs from linearity by only 0.5% over a 25% band. A tapered line designed to approximate an increasing parabolic delay characteristic exhibits a delay deviation of only 0.5% over a frequency band of 13%. An “image” line was fabricated having a decreasing parabolic delay characteristic approximating the mirror image of the increasing parabolic characteristic mentioned above. Although most of the applications of delay synthesis have employed the first longitudinal plate mode, the design procedure has also been applied to shear modes in a strip. For delay lines having nominal delays of 1000 μsec, typical insertion losses are 16 to 25 dB, with discrimination against unwanted signals of 35 to 40 dB.

Synthesis of Dispersive Delay Characteristics by Thickness Tapering in Ultrasonic Strip Delay Lines

Tapering the thickness of a dispersive strip delay line operating in the first longitudinal mode can yield a variety of delay characteristics unobtainable with strips of uniform thickness. A strip whose thickness varies in some manner along its length may be thought of as a number of strip sections of constant thickness in series. The additive delay of these series sections can produce an over-all delay characteristic completely different in form from the delay characteristics of the individual sections. A design procedure involving the methods of linear programming has been developed which allows a unique determination of the taper required to produce a given delay function. Performance data is presented for several delay lines designed to approximate both linear and nonlinear delay-vs-frequency characteristics.

A design parameter for multicomponent tray design estimates

AbstractThis, report develops computational techniques that are useful in multicomponent distillation. A design parameter, (∂n/∂N)s is introduced which is numerically equal to the number of theoretical plates required to do the work of one total reflux tray at the bottom of the enriching section. For a minimum sized tower, (∂n/∂N)s is legs than 3.5. Economic conditions may permit values as high as 6.The ratio of the number of theoretical trays, n, to the minimum number, N, for the combined enriching and stripping sections, including reboiler and condenser, and the ratio of the reflux leaving the enriching section, Ls, to the minimum reflux, LMs, can be found from: A total of 36 sets of minimum reflux data in multi‐component systems were correlated with an average error of −4% in the ratio n/N by these equations.Since (∂n/∂N)s is related to the relative volatility and the compositions of the counterflowing liquid and vapor streams at the bottom of the enriching section, the reflux Ls can be found from a feed tray balance. A procedure is provided for evaluating Ls after a value for the design parameter has been selected.

向流型ガス遠心分離法による同位体の分離, (I)

The influence of a gas flow pattern in a rotor of a counter-current gas centrifuge upon the separation factor and the separative power has been studied. The optimum gas concentration gradient, at which the centrifuge performs the maximum separative power, has been obtained from the equation of the diffusion velocity. The equations with respect to the separation properties have been derived in two regions of the rotor separately, one of which is an upper part above the feed point as a stripping section, the other a lower part as an enriching section.The effects of the radial concentration gradient on the performance of the centrifuge have been considered by means of the flow pattern coefficient K, which depends only upon the flow pattern and approaches to the maximum value, that is, unity, as the neutral layer between the counter currents approaches to the rotor wall.

Reflux in Counter-Current Distribution. I. The Acid-Base Process

A method for separating weak acids or bases is described based on counter-current distribution between an organic solvent and an aqueous phase containing their salts. The process is carried out in a Craig tube system modified to permit solvent flow in both directions. By means of stripping sections the system is run under total or partial reflux. This process is closely analogous to fractional distillation, each tube being equivalent to two theoretical plates. The separation attainable in such a system at equilibrium and the rate of approach to equilibrium are discussed quantitatively and optimum operating conditions evaluated. As an example the separation of o- and p-toluic acids is described.

Operation of a Center-Fed Continuous-Flow Thermogravitational Column with Unequal Flow Rates in the Two Column Sections. Comparison of Theory and Experiment

Equations of Jones and Furry are shown to agree well with experimental data over a range of ratios of rectifying section flow to stripping section flow from 0.3 to 5. On the assumption of an effective feed location which yields maximum separation a tentative modification of the Jones-Furry equation is developed which appears preferable at smaller values of the flow rate.

Plant performance of a 13‐ft.‐diameter extractive‐distillation column

AbstractPlant performance data are presented for a 13‐ft.‐diam., 100‐tray furfural extractive‐distillation column separating iso‐ and n‐butane from 1‐ and 2‐butene. In addition to composition, temperature, pressure, and flow rate of the external streams, values are presented for vapor and liquid compositions and flow rates at a number of different locations within the tower. With the exception of the vapor compositions, which were determined experimentally, the internal conditions were determined by heat and material balances. These data permitted calculation of plate efficiency over various small sections of the column. In the 50‐tray rectifying section, plate efficiency for the isobutane—1‐butene separation was constant at 20%, and in the stripping section the plate efficiency varied from 25 to 45%. The average for the entire column was 25%.The furfural‐column plate efficiencies compare favorably with those predicted from laboratory tests made before the construction of the column to evaluate the performance of the tray design to be employed. The laboratory plate efficiencies were obtained for the desorption of oxygen from oxygen‐rich water with air at the same conditions of volumetric gas and liquid rates to be encountered in the furfural column. When these values were suitably corrected for physical property differences between the two systems, the point efficiencies predicted from the laboratory data for the furfural column ranged from 35% near the top of the column to 25% near the bottom of the column, the average value being 29%.

Stripping and Pick-Up Differential Cross Sections

Stripping and Pick-Up Differential Cross Sections