CC BY
82
https://doi.org/10.29013/AJT-19-9.10-32-39
Karimov I., Associate professor Alimatov B., DSc, professor
"Ferghana polytechnic institute" Republic of Uzbekistan E-mail: [email protected]
HYDRODYNAMICS OF NON SINKING DISPERSE PHASE HOLDING FILTER IN BUBBLING EXTRACTOR
Abstract. In the article, hydrodynamics of a fiberglass fitted with L-L-G system to prevent leakage of supercooled droplets in the mixing phase of the solid phase with inert gas in the mixing zones was studied.
Theoretical studies have suggested a formula for determining the rate of fluid leakage. With this formula, if the resistance coefficient is known, the rate of fluid flowing through the surface of the filter and its associated flow can be determined. As a result, the flow of fluids in the mixing zones of the apparatus was supplied.
To determine the resistance coefficient of the filter, a pilot study was performed on the experimental device of the apparatus. The fibers were selected for the filter and the fibers' sizes were defined. As a result of the research, a formula for determining the contact surfaces, depending on the mass of the glass fibers, which retains the droplets of small particles of heavy fluid, was proposed.
The filter resistance coefficients were determined based on the relative contact surfaces of the fibers mounted on three different base racks and the fluids with three types of surface tension values. Depending on the results of the experiment, the empirical formulas for calculating the resistance coefficient of fiberglass filters installed on the base racks were recommended.
Keywords: bubble extractor, filter, contact surface, glass fiber, base set, external stirring zone, dispersing phase, drop, resistance coefficient, heavy liquid.
Introduction
The use of pneumatic mixing extractors in fluid extraction processes involves less metallic wastewater than the mechanical mixing extractors, smaller than the production area, and has a simplicity and reliability. Such pneumatic mixing extractors are known as barbatal extractors in literature and are among the extraction apparatus in the fluid-liquid system and can be used in chemical, petrochemical, hydrometallurgical, pharmaceutical, biotechnology and food industries [1].
The construction of the paddle-forming bladed extractor [1] is made by us and its constructional structure allows the drainage zone formed in the lower part of the outer mixing zone to escape to the top of the apparatus without falling into small particles of heavy particles. To eliminate this, a floppy fiber was installed on the patrol booth that formed the outer stirrup.
The principle of extruder performance is as follows.
Lightweight fluid (ES) is a part of the gas distribution gear 5. The same pipe flows through heavy
holes (OS) through the holes 8 of the tube 7. In the Patrol 3, the mixture of fluid mixture from bottom to top is mixed intensely by means of a rectifying inert gas through the holes 6 in the gas dispenser. This part of the gas collects the liquids and accumulates in the gas chamber 2.
At the same time, the rest of the inert gas is pumped through the hole 13 through the gas pipe 12 to the annular channels between the 3 and 4 patrol boards. This part of the inert gas, moving from the top to the bottom in transverse channels, passes through the flow of the mixture from the top to the bottom of the fluid. In this process, it mixes the fluid flow and accumulates in the gas heater under the set.
9
When the light fluid passes through the holes 14 and the adjacent glass fiber filters 15 at the bottom of the patrol 4, the particles of small particles that are mixed with it are sealed in the filter and, as a result of their interconnection, turn into large droplets and undergo gravity and inertial forces begins to sink. ight-weight fluid light fluid continues to move higher. Heavy liquid drops stop at the bottom of the canal made by 3 and 4 ports and flow through the slots 16 at the bottom of the post 4 and form a coat layer over the set 2.
The mounting position of the Patrol 4 allows the maximum utilization of the annular channel, allowing the light fluid to pass through the hole 14 and the fibrous fibrous filters 15. The bottom hinges 16 provide only heavy liquids.
Figure 1. Internal part of bubble extractor Figure 2. Overall view of experimental apparatus
The heavy liquid stopping at block 2 moves through pipes 7 through the hole 9 of the hood 9 and goes down the hole 8 through the bottom. The size of the hole 14 formed by the dimensions of
the Patrol 4 and the fibrous filament fibers 15 attached to the base plate are determined by ensuring that the light fluid has a moderate leak rate. The dimensions of the slots 16, which provide heavy
fluid flow through the annular channel formed at the bottom of the Patrol 4, are determined by the condition of leakage, regardless of the heavy liquor consumption.
With an external stirring zone of the apparatus the curing zone is in the form of a container, and the fluid flow passes through the filter. The filter resistance should be selected so that the fluid flows from the outside to the mixing zone. Otherwise, the hy-drodynamic mode of the unit will be broken. This,
in turn, depends on the surface of the filter hinges, the size of the fiberglass filter beds and the specific contact surfaces of the glass fiber filter.
Research object and method.
The filter fluid speed depends on the total resistance of the filter. Theoretical and experimental research was carried out to determine these magnitude. The calculation scheme of the filter inserted into the outer mixing zone of the apparatus is shown in (Figure 3).
Figure 3. Filter's scheme for calculation The center of the filter 1-1 is affected by the the filter. Then the total pressure is calculated as geometric pressure P1 on the annular channel of the follows
device, the pressure P2 from the outside, and the AP + p + P2, Pa (1)
hydrodynamic pressure of the fluid flowing through
It is well known that the hydrodynamic pressure is determined as follows.
AP = ^ ^pt, na
(2)
Where: L - filter resistance coefficient determined by experiences; wc - fluid flow rate through filter, m/s; pp - density of the liquid mixture, kg/m3;
The geometric pressure is determined by the following formula:
P =Papgh(1 -V), na (3)
Where: h - is the level of the fluid flowing down in to the center of the filter, mm; y - value of gas in outer blending zone [2; 3].
External pressure to the center of the filter is defined as P2.
P2 =pgh, na (4)
Where: p - density of dispersion phase, kg/m3. If results of formula (2) (3) and (4) are placed to formula (1) it appears as follows.
, ®2 'P
ap
+
Papgh I1 -V) + Pgh,
na
(5)
(5) If o>c-is found by doing the necessary mathematical operations in equantion (5) it will look as follows.
=
2gh (Pap I1 -V)-P)
M
^ p
/c
(6)
ap
Since the external mixing zone of the device and the sedimentation zone are in the form of adjacent vessels, the pressure created by volume of gas 9 pressures equally. Then equation 6 will look as follows.
=
2gh (Pap -P)(
M
^ P
/c
(7)
$rap
The internal and external mixing zones of the device are designed according to the volume of extraction fluid [4; 5]. Determining the rate of fluid leakage from the filter by using formula 6, depending on this rate, the difference between the amount of fluid flowed from the filter and the fluid flowing to the apparatus can be determined. This, in turn, requires the correct filter resistance of the filter to allow the fluid to flow smoothly when designing.
The object of the research is to use the experimental copy ofthe sampled extractor set up at the Fargonaazot JSC acetic acid regeneration shop for selecting fibrous filament material and detecting its resistance coefficient with the addition of non-depleting dispersed droplets to the gaseous phase of the apparatus (Fig. 2).
In Uzbekistan glass fiber is produced and that material was chose as a filter. Glass fiber is produced in the following marks rOCT10499-95. ISO 9001:15.
Glass fiber measured through electronic balance and follow rates were obtained m=0.15; 0.25; 0.35; 0.45 (figure 4).
Figure 4. Total view of glass fiber filter: m = 0.15 gr; m = 0.25 gr; m = 0.35 gr; m = 0.45 gr
Glass fibers were magnified 400 times in microscope CM001-CYANS and the pictures were taken in DSM camera (figure 5).
Figure 5. View of glass fibers in microscope
2
Average diameter of400 times magnified view of glass fiber equals daf = 3092 m/km If it divides to zoom
d = ^ = 3092 = 8 m/km;
m 400
in order to determine the specific contact surface of glass fiber density determination formula is used
P = L kg/m3 (8)
Where m - glass fiber's mass, kg; V - glass fiber's volume which is found as follow, m3;
V = nR2 • 1 (9)
Where R - glass fiber's radius, m; l - glass fiber's length, m;
In order to find glass fiber's length 8 formula is put to 7th formula
~ (10)
In order to determine the specific contact surface of glass fiber its circle length needs to be found la = 2nR (11)
Total length of glass fiber is produced to its circle length, specific contact surface can be found as follows S = l ■la (12)
By putting of 9th and 10th formulas' values to the 11th formula glass fiber's specific contact surface can be found
m
-• 2nR = —, m2; (13) nR •p R•p
density of glass fiber p = 2200 kg/m3; glass fiber radius R = 0.00004 m;
density of glass fiber p = 2200 kg/m3; by using 6th formula glass fiber's contact surface can be found.
1. If mass of glass fiber m = 0.15 gr, surface is
St = 0.034 m2;
$
2. If mass of glass fiber m = 0.25 gr, surface is St = 0.0565 m2;
3. If mass of glass fiber m = 0.35 gr, surface is
St = 0.0791 m2;
$
4. If mass of glass fiber m = 0.45 gr, surface is
St = 0.1 m2.
$
m
Ld = _ 2
nR ■p
By using of 9th formula lengths of glass fiber were determined
1. If mass of glass fiber m = 0.15 gr, l = 1350 m;
2. m = 0.25 gr, l = 2261 m;
3. If mass of glass fiber m = 0.25 gr, l = 3166 m;
4. m = 0.25 gr l = 4071 m.
Figure 5. Filter installed nozzle and filter's view
Apparatus nozzle which is replaced filter was made X18H10T mark metallic material. By its circle in per 120 ° 3 holes with sizes B*l = 15*45 mm were made. Per hole's surface is S = 0.00066 m2, filtr's will
m '
be established to it (figure 5).
In order to establish of glass fiber to nozzle's holes, metallic net was made X18H10T steel is used. The sizes of square holes are a = 0.25; 0.8; 1.2 mm and thicknesses of the net are S = 0.08; 0.2; 0.25 mm.
They were cut off according to the installation location of the apparatus and used as a base for holding both wrapped glass fibers (figure. 6). The height of the fluid level of the mixing zone in the filter hole is about 400 mm (figure 2). Different densities and surface tension fluids were used to determine the filter resistance ratios. Water, p = 1000 kg/m3, o= 0.073 N/m; ant acit, p = 1198 kg/m3, o= 0.038 N/m; butyl acetate, p = 888 kg/m3, o = 0.0248 N/m.
Figure 6. Views
Obtained results
Experiments were hold in the following sequences. Firstly, holes of the settling nozzles were shut and mixing zone of apparatus was filled with liquid. Internal diameter of the glass tube which forms mixing zone is d1 = 56 mm, value is V = 0.001 m3. On of the holes was opened and liquid's stream time was determined. This experimenting process was held itera-tively a lot. Videos of experiment were taken by Canon E0S700D mark camera.
The resulting image was slowed down by the EDIUS (grass valley) program and the actual flow velocity was determined. At the next stages of the experiment, a = 0.25; 0.8; Each of the 1.2 mm base brackets is fitted to the self-contained and base rings with respect to the specific bonding fibers of the glass fiber S = 0.034; 0.0565; 0.0791; It was determined that the flow of liquids was determined in serial numbers at 0,1 m2. Resistance coefficients were determined on the basis of the selected base supports
of the based nets
and the relative contact surfaces of the glass fibers placed on the filament hole for the leakage time. The experimental sequences were recorded separately for each of the selected liquids.
Based on the experimental researches, research was carried out to produce an empirical formula for determining the coefficient of resistance of the fibrous filament.
The resistivity coefficient is the reference surface of the glass fibers fixed to base sets S$>, the filtered hole surface ST, and the correction coefficient to the ratio of multiplicity of AK. That is,
z =
S,
AKST
(14)
The correction coefficient is defined as follows.
AK = (15)
Here, the resistivity coefficients in the form given in formula 13, | - correction coefficients 1, %T - is resistance coefficients determined by experiments.
Figure 7. The graph shows changes of resistance coefficient, depending on the fluidity of the surface tension
Ak
35
:o
LS
10
y /s w >
/
0.02
0.0Î
o.cw
0.0S
0.06 0,07 0.08 c, N/ffi
* - bucking net - = — = o 32;
a 0.25 S 0 2
- bucking net; —= — = 0.25;
a 0.8
® - bucking net - = 025 = 0.21
a 0.12
Figure 8. The graph shows changing correction coefficient according to the liquid's surface tension:
The resistivity coefficient f was determined by formula 13, depending on the specific contact surfaces of the glass fibers identified by formula 12 and the filter hole surface (Sm = 0.00066 m2).
Depending on the values of the experimentally determined resistor coefficients, the correction factors were correlated with Formula 14.
The 13-empirical formula is recommended for calculating the resistance coefficients depending on the size of stand sets and the specific bonding areas of the glass fibers.
The main function of the selected set is to hold the fibers of the glass and serve as a base.Theoretical values of resistance coefficients were compared with the experimental values using the recommended empirical formula. The error between them was A = ±4%.
Based on the experimental results, it is recommended to measure the size of the base hole by taking into account the size of the fiberglass diameter a = 1 ^ 1.2 mm. Because, if larger sizes are selected,
the resistance factor can be reduced, but the glass fiber is removed from the hole and the filter can change stability. The results of the experimental researches have been based on exponential graphics of processing of the computer (Figures 7, 8).
Conclusion
Theoretical and experimental studies have suggested a formula for detecting specific surfaces, depending on the mass of the glass fibers, which holds the small particulate drops of heavy liquids. Resistance coefficients were determined based on the specific fibers of glass fibers at different values and the different surface tension of the fluids. The empirical formula for the resistance coefficient was recommended depending on the results obtained from the experiment. With these recommended formulas, the basic parameters of the filter to be installed on the apparatus will be projected. Because the filter's ability to hold fluids and hold down heavy particles ofheavy particles, which are not buried, will depend on its resistance coefficients
References:
1. Alimatov B. A., Sokolov V. N., Sadullayev Kh.M., Karimov I. T. Multistage bubbling extractor. A.S. No. 1607859 (USSR), BI No. 43, 1990.
2. Karimov I. T. Studying of hydrodynamics processes of bubbling extractors' mixing zone d.t.sc. diss. T.TSTU, 2001.- 131 p.
3. 3. Sokolov V. N., Domanskiy I. V. Gaz-liquid reactors - L.: "Machine building", 1976.-216 p.
4. Karimov I. T. The method of determining bubbling extractor's sizes of mixing zone.FerPI scientific-technical journal? 2005? - No. 2.- P. 111-114.
5. Karimov I. T., Akhrorov A. A., Qakhkhorov I.I (Republic of Uzbekistan) The method of of determining the size of the mixing zone bubbling extractor. International scientific review of the problems and prospects of modern science and education. Boston. USA. February 21-22, 2019.
