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TECHNICAL SCIENCES
THE METHOD OF DETERMINING THE SIZE OF THE MIXING ZONE
BUBBLING EXTRACTOR
1 2 3
Karimov I.T. , Ahrorov A.A. , Kahorov I.I. (Republic of Uzbekistan) Email: [email protected]
1Karimov Ikromali Toimatovich - Associate Professor;
2Ahrorov Akmaljon Akramovich - Researcher; 3Kahorov Islomjon Ikromovich - Student, DEPARTMENT OF TECHNOLOGICAL MACHINES AND EQUIPMENT, FERGANA POLYTECHNIC INSTITUTE, FERGANA, REPUBLIC OF UZBEKISTAN
Abstract: in order to work in ordinary intensified operation the internal and external mixing zones of the bubbling extractor to work in the mixing mode of the same intensity, the gas content values in these zones must be equal. This, in turn, depends on the gas velocity in both zones. These speeds depend on the cross-sectional surfaces of the mixing zones. The article is based on the above requirements, the dignity of bubbling extractors and the boundary value of the gas velocity and gas content for intensive hydrodynamic mixing of internal and external perimeter zones of the apparatus. An equation is proposed for calculating the size of the mixing zones of the apparatus depending on the optimal gas velocity and gas content. This equation allows us to design a mixing apparatus.
Keywords: bubbling, extractor, mixing zone, dimension, intensity, gas content, hydrodynamic, mixing, gas velocity, liquid velocity.
МЕТОДИКА ОПРЕДЕЛЕНИЯ РАЗМЕРОВ СМЕСИТЕЛЬНОЙ ЗОНЫ БАРБОТАЖНОГО ЭКСТРАКТОРА
12 3
Каримов И.Т. , Ахроров А.А. , Кахоров И.И. (Республика Узбекистан)
1 Каримов Икромали Тожиматович - кандидат технических наук; 2Ахроров Акмалжон Акрамович - исследователь;
3Кахоров Исломжон Икромович - студент, кафедра технологических машин и оборудования, Ферганский политехнический институт, г. Фергана, Республика Узбекистан
Аннотация: для того чтобы внутренние и внешние зоны смешивания барботажного экстрактора работали в режиме смешивания одинаковой интенсивности, значения газосодержания в этих зонах должны быть равными. Это, в свою очередь, зависит от скорости движения газа в обеих зонах. Эти скорости зависят от поверхностей поперечного сечения зон смешивания. В статье приведено исходя из вышеуказанных требований, достоинство барботажных экстракторов и граничное значение скорости газа и газосодержания для интенсивного гидродинамического смешивания внутренных и внешних перемешивающих зон аппарата. Предложено уравнение для расчета размера перемешивающих зон аппарата в зависимости от оптимального значения скорости газа и газосодержания. Это уровнение дает нам возможность проектировать перемешивающую зону аппарата.
Ключевая слова: барбртаж, экстрактор, перемешивающих зон, размерность, интенсив, газосодержание, гидродинамический, перимешивание, скорость газа, скорость жидкости.
In order to increase the efficiency of the process by increasing the time of mixing of liquids by barbotizing inert gas, we have developed the design of a multistage bubble extractor [1], which according to our data is one of the promising for use in liquid extraction processes. Devices and the principle of operation of the extractor are presented in Fig. 1.
Fig. 1. Intensified bubbling extractor
When the joint movement from the bottom up inside the pipe 3, the liquids are intensively mixed with a bubbling inert gas that flows from the "gas cushion" under the partition 2 through the holes 6. Then the mixture of liquids moves from top to bottom in the annular channel between pipes 3 and 4, and go into the settling section where drops of heavy liquid are deposited in a continuous layer; at the same time, the interface between light and heavy liquids determines the position of the upper edge of the overflow pipes 7 for heavy liquids.
During the movement from top to bottom in the annular channel between the pipes 3 and 4, the liquids are mixed with an additional portion of inert gas, which is supplied from the "gas cushion" through holes 13 of the tubes 12.
The stable operation of such an extractor depends on the uniform distribution of the inert gas into the internal nozzle 3 and into the annular channel between the nozzles 3 and 4 in order to create there equal hydrodynamic regimes determined by the equality of the volumetric gas
contents. But this is due to the overcoming of certain features of the apparatus, the scraping inside the nozzle 3 is a mixture of liquids and the inert gas is in direct flow mode, and in the annular channel between the nozzles 3 and 4 there is a mixture of liquids and inert gas moving in countercurrent mode. With a direct flow of liquid and inert gas, the volumetric gas content is determined by the dependence [2, 5]:
Фо = (l - 0,04w'c )ф (1)
In the case of countercurrent motion of a liquid and an inert gas, the volumetric gas content can be determined by the dependence;
V=(1 + 0,04wc ")V (2)
Where: w's is the reduced fluid velocity of the internal mixing zones of the apparatus; w'c - is the reduced fluid velocity of the external mixing zones of the apparatus; w''c is the gas content in the stationary liquid. An empirical equation has been proposed for calculating ф' [3]
<p' = 2 , 4 7 - 97
Wr -reduced gas velocity in the mixing zone, m / s;
In order to test the possibility of using dependencies (1 ^ 3) for calculating the volumetric gas content of the mixing zones of a bubble extractor, we carried out experimental studies in the laboratory apparatus of the apparatus and the obtained results were publicized [4].
In the bubbly type apparatus, the velocity of the gas phase motion has the main influence on the hydrodynamic regime and gas content. The mode of movement of the gas phase inside the liquid is conventionally divided into 2 main groups; 1) bubbling mode, which exists at the given gas speeds
wg < 0,05 м/ сек. 2) the mode of coalescing bubbles, which exists at reduced gas velocities wg > 0,05 м/ сек. The transition from the first mode to the second occurs at a gas velocity of 0.05 m/s. Bubble mode gas content ф0,ф!<0,3 [3]. Therefore, for uniform and stable operation of the mixing zones of the apparatus, ф0 = ф1, conditions must be met. To meet these conditions, it is necessary to choose the right cross-section of the pipe inside and outside mixing zones of the apparatus.
The diameter of the internal bubbling pipe is determined depending on the flow rate of the extracted liquid by the following equation.
+ ^ м ; (4)
Q-extractable fluid consumption, m3 / h; шс -the speed of the extracted fluid during movement in the internal bubbling nozzles, m / s; dt- the outer diameter of the flow pipes of heavy liquid, is selected from the condition. (dt =d0(3^5)), d0 -the diameter of the hole for the supply of heavy fluid in the overflow pipes, are selected depending on the performance of the heavy phase.
The inner diameter of the annular channel is determined by such conditions that the velocity of the fluid is less than the velocity of the gas, since in this zone the movement of liquids and gases is countercurrent.
wr > юс" (5)
Otherwise, if the velocity of the fluid is high, gas bubbles enter the lower part of the annular channel through the settling zones of the apparatus. As a result, the intensity of mixing of liquids in the annular channel decreases.
Or it is necessary to take into account and multiply by the gas velocity the dimensionality coefficient K, which takes into account the velocity of the fluid,
then 5 inequalities have the form
K wr = rac (6)
K - dimensionality coefficient is determined experimentally. The velocity of the gas passing along the surface of the cross section of the annular channel is determined depending on the gas content according to the following equation [3].
rar =a 9i(l- 91); M/ceK ; (7)
where a is the coefficient corresponding to the speed of a single bubble (a = 30 ^ 32 cm/ s), ( is the volumetric gas content of the external bubbled pipes. The cross-sectional area of the annular channel is defined as follows.
by equation.
Sk = SBH -S0= —---t2- , M2 (8)
4 4
SBH -total cross-sectional area of external bubbling nozzles, m2, S0-cross-sectional area of internal bubbling nozzle, m2, D is the inner diameter of the outer bubbling nozzle, D0 is the outer diameter of the inner bubbling nozzle. (pic-1). The flow rate of fluid flowing through the cross-sectional area of the annular channel is determined by the following equation.
Q = (f£! - iT?) x 3 600 , M3/nac; (9)
Where ( " c is the flow rate of the fluid in the annular channel, m / s;
From equation 9, we get
( "c =—- M/ceK; (10)
Substituting the value of equation 7 and 10 into equation 6, we get
Ka a, (1 — o,) = -¡-T-^- M/ceK; (11)
From equation 11, we get Z)2
From equation 12 we find the internal daimeter of the external bubbling pipe
D2—D0 =-- M; (12)
D = I--+ D02 m; (13)
-J Kna<p1(±-<p1)-3600 u ' v /
Using equation 13, the diameter of the external bubbling nozzle is determined depending on the velocity of the gas and the liquid. This makes it possible to intensively and uniformly mix the extractable liquids in the internal and external mixing zones of the bubbling extractor.
References / Список литературы
1. Алиматов Б.А., Соколов В.Н., Садуллаев Х.М., Каримов И.Т. Многоступенчатый барботажный экстрактор. А.С. № 1607859 (СССР). БИ № 43, 1990.
2. Шендерев Л.З., Дильман. ВВ. Движение газа в барботажных реакторах. ТОХТ,1988. № 4. С. 496-510.
3. Соколов В.Н., Доманский И.В. Газожидкостные реакторы Л.:«Машиностроение», 1976. 216 с.
4. Алиматов Б.А., Каримов И.Т., Соколов В.С. Экспериментальное исследование газосодержание в смесительных элементах барботажного экстрактора. научно-техн журн. ФерПИ. № 1. С. 75-77.
5. Каримов И.Т. Исследование гидродинамических процессов перемешивающих зон барботажного экстрактора. канд. дисс. Т. ТДТУ, 2001. 131б.
OPTIMIZATION OF MINING WORKS HARMFUL INFLUENCE
ESTIMATION ON THE BASIS OF DEFORMATIONS DISTRIBUTION
VISUALIZATION 1 2 Novozhenin S.Yu. , Zozulya A.A. (Russian Federation)
Email: [email protected]
1Novozhenin Sergei Yurevich - PhD in Engineering Sciences, Associate Professor; 2Zozulya Anastasiya Andreevna - Student, DEPARTMENT OF MINING SURVEYING, SAINT-PETERSBURG MINING UNIVERSITY, SAINT-PETERSBURG
Abstract: the article proposed a method to optimize the assessment of the harmful effects of mining on the earth's surface. It consists in the preliminary mapping of the distribution of displacements or deformations using the Surfer software. The magnitudes of displacements and deformations are preliminarily calculated using the well-known standard curve method. Then the created map can be used in conjunction with the plan of the surface on which the protected objects are highlighted. The use of this method will significantly reduce the time spent on interpolation of strain values when evaluating the harmful effects of mining operations on buildings and structures. Keywords: displacement of rocks, assessment of harmful effects, subsidence, horizontal deformations.
ОПТИМИЗАЦИЯ ОЦЕНКИ ВРЕДНОГО ВЛИЯНИЯ ГОРНЫХ РАБОТ
НА ОСНОВЕ ВИЗУАЛИЗАЦИИ РАСПРЕДЕЛЕНИЯ ДЕФОРМАЦИЙ
12
Новоженин С.Ю. , Зозуля А.А. (Российская Федерация)
1 Новоженин Сергей Юрьевич - кандидат технических наук, доцент; 2Зозуля Анастасия Андреевна - студент, кафедра маркшейдерского дела, Санкт-Петербургский горный университет, г. Санкт-Петербург
Аннотация: в статье предложен способ оптимизации оценки вредного влияния горных работ на земную поверхность. Он заключается в предварительном составлении карты распределения сдвижений или деформаций с помощью программного продукта Surfer. Величины сдвижений и деформаций предварительно рассчитываются с помощью
