JP2003314804A - Calculation method of gas liquid interface shape of cyclone separator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for precisely calculating the shape and the height of a gas liquid interface of a cyclone separator. <P>SOLUTION: An upper part pressure loss ΔP<SB>t</SB>produced in saturated vapor in the upper part of the cyclone separator is found based on an inflow quantity per second Q<SB>s</SB>of the saturated vapor included in gas liquid mix fluid and the density ρ<SB>s</SB>of the saturated vapor. A lower part pressure loss ΔP<SB>b</SB>produced in the saturated water in the lower part of the cyclone separator is found based on the inflow quantity per second Q<SB>w</SB>of the saturated water included in the gas liquid mix fluid and the density ρ<SB>w</SB>of the saturated water. The turning speed V<SB>θ</SB>of the outer circumferential part of the gas liquid mix fluid turning in the cyclone separator is found based on the inflow quantity of the gas liquid mix fluid. The shape and the height of the gas liquid interface are found from the speed V<SB>θ</SB>, the pressure losses ΔP<SB>t</SB>and ΔP<SB>b</SB>, and the densities ρ<SB>s</SB>and ρ<SB>w</SB>. They are calculated by taking account of the upper pressure loss ΔP<SB>t</SB>and the density ρ<SB>s</SB>so as to precisely calculate the shape and the height. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for calculating the shape and height of a gas-liquid interface of a cyclone separator provided on a steam drum of a power generation boiler or the like.

2. Description of the Related Art In a power generation boiler, a gas-liquid mixed fluid (saturated steam + saturated water) generated by heating in a furnace is separated into steam and saturated water, and only steam is sent to a turbine side. There is a steam drum for. A cyclone separator for separating the gas-liquid mixed fluid into saturated steam and saturated water by centrifugal separation is provided in the steam drum. FIG. 2 is a schematic view of the steam drum, FIG. 2B is an external view of the steam drum as seen from above, and FIG. 2A is a schematic cross-sectional view as seen from the direction A of FIG. 2B. It is a figure. The steam drum 1 includes a steam drum body 110 having a shroud 105, a cyclone separator 3,
It has a scrubber 109 and an introduction pipe 2. And in the inside, the water storage part 1 in which the separated water 119-2 exists.
07 and the steam part 108 in which the separated steam 119-1 exists is formed. The rising pipes 111 to 114 and the saturated steam pipe 115 are connected to the upper portion of the steam drum 1, and the downfall pipe 116 is connected to the lower portion thereof. The steam drum body 110 has a hollow cylindrical shape, and the center axis (center axis) of the cylinder is oriented in the horizontal direction. The gas-liquid mixed fluid M supplied from the rising pipes 111 to 114, which are opened and connected to the upper part, by a device provided inside
X is gas (steam 119-1) and liquid (water 119-2)
And separated. The separated gas (steam 119-1) and liquid (water 119-2) are separately sent to the outside. Here, one divided by a vertical plane including the central axis of the steam drum is called the front of the can and the other is called the rear of the can. In FIG. 2B, the upper side of the steam drum main body 110 in the drawing is the rear of the can and the lower side thereof is the front of the can. The shroud 105 is an area of a space sandwiched between an outer surface (curved surface portion) of a cylinder having a radius smaller than that of the steam drum body 110, which is coaxial with the steam drum body 110, and an outer surface (curved surface portion) of the steam drum body 110. is there. The shroud 105 is a steam drum body 110.
The gas-liquid mixed fluid MX existing in the upper half of the steam drum main body 110 is introduced into the steam drum main body 110. The introduction pipe 2 is a cylindrical pipe extending from the inside of the shroud 105 toward the inside of the steam drum body 110. One end of the introduction pipe 2 is openly connected to the shroud 105, and the other end is openly connected to the cyclone separator 3. The introduction pipe 2 supplies the gas-liquid mixed fluid MX that has passed through the shroud 105 to the cyclone separator 3. The cyclone separator 3 is installed symmetrically with respect to the vertical plane before and after the can. The cyclone separator 3 has a cylindrical outer shape, and the introduction pipe 2 is open and connected to the outer surface (curved surface portion) of the cyclone separator 3. Also, one end of the steam part 10 is connected to the water storage part 107
Open to 8 respectively. Then, the gas-liquid mixed fluid MX supplied from the introduction pipe 2 is supplied with water 119-2 and steam 119.
-1 and separate. The separated water 119-2 is the water storage unit 1.
07, and the separated steam 119-1 is steam part 10
Go to 8. The detailed internal structure of the cyclone separator 3 will be described later. The water 119-2 existing in the water storage section 107 is
It is sent to the outside through a downcomer 116 which is open and connected to the lower part of the steam drum body 110. Steam part 10
The steam 119-1 existing in No. 8 contains mist (fine water droplets) and travels to the scrubber 109. The symbol L indicates the water surface of the water storage section 107 (water surface in the drum). The scrubber 109 removes the mist-containing vapor 119-1 by aggregating the mist. The water that the mist aggregates is
It is dripped from the scrubber 109 to the water storage section 107. The steam 119-1 from which the mist has been removed is the steam drum body 1
Saturated steam pipe 11 which is open and connected to the upper part of 10
It is sent to the outside after passing through 5. The scrubber 109 is symmetrically installed in the vertical plane before and after the can.
The ascending pipes 111 to 114 are pipes for supplying the gas-liquid mixed fluid MX supplied from the outside to the steam drum. From the rising pipe 111 and the rising pipe 112 in front of the can to the steam drum body 11
Gas-liquid mixed fluid MX supplied to 0 and the rising pipe 11 after the can
3 and the gas-liquid mixed fluid MX supplied to the steam drum main body 110 from the rising pipe 114 are approximately equal in amount. The saturated steam pipe 115 has a steam 119 separated by a steam drum.
It is a pipe for supplying -1 to the outside. Saturated steam pipe 1
The lines 15 are open and connected at equal intervals on a straight line (along the central axis direction) formed by the upper part of the steam drum body 110 intersecting with the vertical plane. The downcomer pipe 116 is a pipe for supplying the water 119-2 separated by the steam drum body 110 to the outside. The downcomer pipes 116 are open and connected at equal intervals on a straight line (along the central axis direction) formed by the lower portion of the steam drum body 110 intersecting a vertical plane. In the steam drum 1 having such a configuration, the gas-liquid mixed fluid MX supplied from the outside is supplied to the rising pipe 1
It is supplied to the steam drum main body 110 via 11 to 114. The gas-liquid mixed fluid MX passes through the shroud 105 toward the introduction pipe 2. At this time, the gas-liquid mixed fluid MX passing through the shroud 105 on the front side of the can and the gas-liquid mixed fluid MX passing through the shroud 105 on the rear side of the can are approximately equal in amount. After reaching the introduction pipe 2, the gas-liquid mixed fluid MX enters the cyclone separator 3 and is separated into steam 119-1 and water 119-2. Separated steam 119-
1 goes to the steam section 108 and water 119-2 goes to the water storage section 107. At this time, the steam 119-1 contains mist. The water 119-2 of the water reservoir 107 is the downcomer 116.
It is sent to the outside via. The mist of the vapor 119-1 containing the mist of the evaporator 108 is separated in the scrubber 109. The separated mist drops into the water storage unit 107. The separated steam 119-1 is the saturated steam pipe 115.
It is sent to the outside via. 3A and 3B are schematic views of the cyclone separator 3 provided in the steam drum 1, where FIG. 3A is a vertical sectional view and FIG. 3B is a horizontal sectional view. The cyclone separator 3 is the cyclone part 1 located below.
3 and a primary scrubber portion 23 integrally connected to the upper portion of the cyclone portion 13. The cyclone portion 13 has a cylindrical tubular body 14, and the axial center line of the tubular body 14 is oriented substantially in the vertical direction. The cylindrical body 14 is provided with an opening that opens in the tangential direction, and the introduction tube 2 is connected to the opening at the tangential direction and at an angle inclined with respect to the axial direction. The lower portion (lower end) of the cylindrical body 14 is arranged at a position submerged below the water surface L in the drum, and the communication passages 14a and 14b are provided.
And the like through the inside of the steam drum. The upper end of the cylindrical body 14 is connected to the hollow portion 24 provided at the center of the primary scrubber portion 23 via the communication portion 15. Hollow part 24
A swirl vane 25 is arranged around the. The swirl vane 25 is supported by the upper plate 27 via the support cylinder 30. Further, the cap member 2 is provided on the outer periphery of the swirl vane 25.
6 is arranged and surrounds the outer periphery of the swirl vane 25. The cap member 26 is not arranged so as to seal the swirl vane 25, the hollow portion 24, etc., and has a flow path 28 through which fluid such as steam or mist passes at the upper and lower edges thereof.
29 to form 29. The gas-liquid mixed fluid MX supplied to the cylindrical body 14 via the introduction pipe 2 is
It swirls as a forced vortex inside, and is separated into a steam part mainly containing saturated steam S and a water part mainly containing saturated water W with a gas-liquid interface (liquid level) B as a boundary. Due to the turning, the shape of the gas-liquid interface B in the cylindrical body 14 becomes a parabolic surface in which the central portion is dented and rises toward the outer peripheral portion. The water portion, which is the lower layer of the gas-liquid interface B, together with a very small amount of bubble portion (steam portion) mixed therein, is connected from the lower end side of the tubular body 14 to the communication passage 14a, as indicated by arrows W ₁ and S ₁ , respectively. , 14
It is discharged into the steam drum 1 via b. On the other hand, the cylinder 14
The vapor portion mainly composed of the saturated vapor S, which is separated by the above and becomes the upper layer of the gas-liquid interface B, reaches the primary scrubber portion 23 through the communicating portion 15, is given a swirling force by the swirling vanes 25, and partially separates the mixed mist. , And steam and mist, respectively, and are discharged from the flow paths 28 and 29 to the outside of the primary scrubber portion 23 as shown by arrows S ₂ and W ₂ . Most of the mist falls to the saturated water W below by the primary scrubbing section 23 and the scrubber 5, but only a small portion of the mist stays upward together with the saturated steam S and is sent out from the saturated steam pipe 115 to the outside of the steam drum. To be done. Here, the amount of the gas-liquid mixed fluid (especially saturated moisture) flowing from the introduction pipe 2 into the cylindrical body 14,
The gas-liquid interface B moves up and down according to the inflow speed, and the outer peripheral portion of the gas-liquid interface B, especially the gas-liquid interface B moves up and down depending on the size of the swirling speed. When the gas-liquid interface B and the outer peripheral portion thereof rise, the amount of mist contained in the separated saturated vapor S increases. For example, when the gas-liquid interface B reaches the upper end portion of the cylindrical body 14, the communication portion 15, or the vicinity thereof, mist is scattered from the gas-liquid interface B, and the scattered mist is contained in the saturated steam S. The mist contained in the saturated steam S increases,
When the separation capacity of the temporary scrubber unit 23 or the scrubber 5 is exceeded, the amount of mist sent from the saturated steam pipe 115 to the turbine or the like increases. As a result, the steam temperature decreases, which leads to an unfavorable state such as a decrease in power generation efficiency of the power generation boiler. Therefore, in order to prevent the amount of mist from increasing in this way, the gas-liquid interface B of the cyclone separator is
There is a demand for a method for accurately calculating the shape or the height of the gas-liquid interface B, and several calculation methods have been considered.

However, the conventional method of calculating the gas-liquid interface shape is based on the physical condition of the lower layer side of the gas-liquid interface B (that is, the density of the saturated water W which is the physical condition of the saturated water W, The shape of the gas-liquid interface is calculated by considering only the pressure loss on the lower end side of the cylindrical body 14). Therefore, the shape of the gas-liquid interface could not be obtained accurately. Therefore,
An object of the present invention is to provide a method for accurately calculating the shape of the gas-liquid interface and the height of the gas-liquid interface of the cyclone separator.

In order to achieve the above object, in the method of calculating the gas-liquid interface shape of a cyclone separator according to the present invention, a gas-liquid mixed fluid consisting of saturated steam and saturated water flows in and out. A method for calculating the shape of a gas-liquid interface in a cyclone separator that separates a gas-liquid mixed fluid into saturated steam and saturated water by centrifugation, wherein the upper pressure loss ΔP _t of the cyclone separator is defined as Is calculated based on the inflow rate Q _s of the saturated steam per second and the density ρ _s of the saturated steam contained in the lower pressure loss ΔP of the cyclone separator.
_b is determined on the basis of the inflow rate Q _w of the saturated water contained in the gas-liquid mixed fluid per second and the density ρ _{w of the} saturated water, and the outer circumference of the gas-liquid mixed fluid swirling in the cyclone separator. The swirl velocity V _{θ of the} portion is obtained based on the inflow amount of the gas-liquid mixed fluid, and the shape of the gas-liquid interface of the cyclone separator is obtained by the following formula.

[Equation 8] Where z is from the center of the cylinder of the cyclone separator
From the lower end of the cylinder at the point of radius r to the gas-liquid interface
Height, g is gravitational acceleration, R is the cyclone separation
Inner diameter of cylinder, H_wIs the cylinder of the cyclone separator
Saturated water outside the cyclone separator from the bottom of the
The height to the surface of the water. In addition, the cyclone according to the present invention
The method of calculating the gas-liquid interface shape of the separator is a cylindrical tube.
Has a body, and the introduction pipe is tangentially attached to the outer peripheral portion of the cylinder.
The angle α to the plane perpendicular to the axis of the cylinder
And saturated steam that flows in through the inlet pipe and satiety
Saturated steam is generated by centrifuging a gas-liquid mixed fluid consisting of Japanese water.
-Liquid field in a cyclone separator that separates into saturated water and saturated water
A method for calculating the shape of a surface, the method comprising:
Top pressure loss ΔL_tIs included in the gas-liquid mixed fluid.
Inflow rate Q of the saturated steam per second_sAnd before
Saturated water vapor density ρ_sBased on the
Lower pressure loss of separator_bThe gas-liquid mixed flow
Inflow rate Q of the saturated water contained in the body per second_wand
Density ρ of the saturated water _wBased on the following formula
The shape of the gas-liquid interface of the cyclone separator is also calculated.
Of.

[Equation 9] Where z is the radius r from the center of the cylinder
Height from the lower end of the cylinder to the gas-liquid interface, g is gravity acceleration
Degree, R is the inner diameter of the cylinder, H_wIs from the bottom of the cylinder to the front
The height of saturated water outside the cyclone separator to the surface of the water
S,_iIs the cross-sectional area of the introduction tube. According to the invention
And the density and saturation of saturated steam in the cyclone separator.
Considering the upper pressure loss of the Icron separator,
The shape of the surface is calculated. Therefore, the gas-liquid interface is more positive.
You can definitely ask. Cyclone Sepa according to the invention
The height of the outer peripheral part of the gas-liquid interface of the evaporator is calculated using saturated water.
A gas-liquid mixed fluid consisting of steam and saturated water enters the
Saturated water vapor mixture is saturated with saturated steam by centrifugation
Outside the gas-liquid interface inside the cyclone separator that separates into water
A method for calculating the height of a peripheral portion, the method comprising:
Upper pressure loss of the palletator ΔP_tTo the gas-liquid mixed fluid
Inflow rate Q of the saturated water vapor contained per second_sand
Density ρ of the saturated steam_sBased on the above-mentioned cycl
Ron separator bottom pressure loss ΔP_bThe above gas-liquid mixture
Inflow rate Q of the saturated water contained in the fluid per second_wAnd
And the saturated water density ρ_wBased on
The gas-liquid mixed fluid swirling in the cyclone separator
Speed V of the outer periphery of _θTo the inflow amount of the gas-liquid mixed fluid
Based on the following equation, the cyclone separation
Height z of the outer peripheral part of the gas-liquid interface_RIs to seek.

[Equation 10] Here, g is the gravitational acceleration, and _Hw is the height from the lower end of the cylinder of the cyclone separator to the water surface of the saturated water outside the cyclone separator. Further, the method of calculating the height of the outer peripheral portion of the gas-liquid interface of the cyclone separator according to the present invention has a cylindrical tubular body, and the introduction pipe is tangential to the outer peripheral portion of the tubular body and A cyclone that is connected at an angle α with respect to a vertical plane with respect to the axis of the body and that separates saturated gas and saturated water by centrifugal separation from a gas-liquid mixed fluid that flows through the introduction pipe and that is composed of saturated steam and saturated water. A method for calculating a height of an outer peripheral portion of a gas-liquid interface in a separator, wherein an upper pressure loss ΔP _t of the cyclone separator is calculated by calculating an inflow rate Q _s of the saturated steam contained in the gas-liquid mixed fluid per second. And the density ρ of the saturated steam
The lower pressure loss ΔP _b of the cyclone separator is calculated based on _s , and the inflow rate Q _w of the saturated water contained in the gas-liquid mixed fluid per second and the density ρ _{w of the} saturated water.
Then, the height z _R of the outer peripheral portion of the gas-liquid interface of the cyclone separator is obtained by the following formula.

[Equation 11] Here, g is the gravitational acceleration, _Hw is the height from the lower end of the cylindrical body to the surface of the saturated water outside the cyclone separator, and _Si is the cross-sectional area of the introduction pipe. Also according to the present invention, the shape of the gas-liquid interface is calculated in consideration of the density of saturated steam of the cyclone separator and the upper pressure loss of the cyclone separator. Therefore, the gas-liquid interface can be obtained more accurately.

BEST MODE FOR CARRYING OUT THE INVENTION Since the constructions of the steam drum and the cyclone separator are the same as those described with reference to FIGS. 2 and 3 in the section of the prior art, detailed description thereof will be omitted here. . 1 (a) and 1 (b) show various symbols necessary for obtaining the liquid surface shape of the cyclone separator in a horizontal cross section and a vertical cross section, respectively. First, the symbols in FIG. 1 and the symbols appearing in the following calculation formulas will be described.
The left side of the colon ":" is the symbol, and the right side is the explanation of the symbol. g: Gravity acceleration [m / s ² ] H ₀ : Height of the cylinder 14 of the cyclone separator 3 (height from the lower end to the upper end of the cylinder 14) [m] H _w : From the lower end of the cylinder 14 to the steam drum Height of saturated water W in 1 to the water surface L [m] R: Inner diameter of the cylinder 14 [m] r: Parameter P _b indicating the distance (radial position) from the center of the cylinder 14: Cylinder Radius r at the water depth (H = 0) at the lower end of 14
Pressure points [Pa] _{P b0:} pressure [Pa] _{P t} of the center of the cylindrical body 14 at the lower end of the depth of the cylindrical body 14 (H = 0) (r = 0): the upper end of the cylindrical body 14 Height ( H = H ₀ ) Pressure at radius r [Pa] P _t0 : Pressure at center (r = 0) of cylinder 14 [Pa] at height of top of cylinder 14 (H = H ₀ ). Q _s : Amount of saturated steam S flowing from the introduction pipe 2 into the cylinder 14 per second [m ³ / s] Q _w : Amount of saturated water W flowing from the introduction pipe 2 into the cylinder 14 per second [m ³ / s] S _i : cross-sectional area [m ² ] S _{s of} introducing tube 2 (opening of cylinder 14): cross-sectional area of cylinder 14 (= πR ² ) [m ² ] V _θ : inside cylinder 14 Velocity of the gas-liquid mixed fluid MX (the swirl velocity of the forced vortex) [m /
s] V: Peripheral velocity of gas-liquid mixed fluid MX (rotational velocity of forced vortex) at a point of radius r [m / s] z: Height from the lower end of the cylinder 14 to the gas-liquid interface B at a point of radius r Height [m] z ₀ : height from the lower end of the cylinder 14 to the gas-liquid interface B at the axis (center) of the cylinder 14 [m] α: inflow direction of the gas-liquid mixed fluid MX (introduction pipe 2) And the horizontal plane (a plane perpendicular to the axis of the cylinder 14) [ra
d] ρ _s : Saturated water vapor density [kg / m ³ ] ρ _w : Saturated water density [kg / m ³ ] σ _t : Pressure loss coefficient at the upper outlet of the cyclone separator 3 σ _b : Pressure at the lower outlet of the cyclone separator 3. Loss coefficient Here, the height H _{0 of} the tubular body 14, the inner diameter R of the tubular body 14, the cross-sectional area S _s (= πR ² ) of the tubular body 14, the cross-sectional area S _i of the introduction pipe 2, and the angle α are the cyclone. It is a constant known in advance from the design value of the separator 3 or by measuring the cyclone separator 3. The saturated water vapor density ρ _s and the saturated water density ρ _w are values determined by the average pressure and temperature inside the steam drum 1. Therefore, the saturated water vapor density ρ _s and the saturated water density ρ _w are obtained based on the pressure value and temperature measured by a sensor or the like (not shown) that measures the internal pressure and internal temperature of the steam drum 1, respectively. Alternatively, under the condition that the temperature and the pressure are controlled to be constant, both the densities ρ _s and ρ _w can be treated as constant constants. The height (water level) H _w is detected by a water level sensor (not shown) for measuring the water level provided inside the steam drum 1. Alternatively, the height _Hw is controlled by a controller (not shown) so as to be constant based on the value detected by the water level sensor. Therefore, the height H _w is a value known from the measured value by the water level sensor or a constant known from the control target value or design value. The inflow saturated steam amount Q _s and the inflow saturated water amount Q _w are values that are set and controlled according to the operating state of the power generation boiler, and are values that are found from set values (design values) or control target values. . The pressure loss coefficient σ _t is
The shape and size of the upper outlet of the cyclone separator 3 (for example, the communication portion 15, the swirl vane 25, the cap member 2)
6, a constant value determined by the shape and size of the flow paths 28, 29 (see FIG. 3) and the like, and is a value that can be obtained in advance by calculation, test, etc. Similarly, the pressure loss coefficient σ _b also has the shape and size of the lower outlet of the cyclone separator 3 (for example, the communication passages 14a and 14b (see FIG. 3).
It is a constant value determined by the shape, size, etc.) and can be obtained in advance by calculation, test, etc. A calculation formula for obtaining the shape of the gas-liquid interface B is derived below using these symbols. At the lower end of the cylindrical body 14 of the cyclone separator 3, the radial pressure is balanced. Therefore, the pressure P _b can be expressed by the following formula (1) as a formula expressing the pressure balance in the radial direction.

[Equation 12] Similarly, the pressure in the radial direction is also balanced at the upper end of the tubular body 14, so the pressure P _t can be expressed by the following formula (2) as a formula expressing the pressure balance in the radial direction.

[Equation 13] Since the pressure in the vertical direction (vertical direction) is also balanced at the radius r of the cylindrical body 14, the pressure P _b is expressed by the following equation (3) as an equation representing the pressure balance in the vertical direction.
Can also be expressed as

[Equation 14] Similarly, the pressure P _b0 is the axial center (r =
As an expression expressing the pressure balance in the vertical direction (vertical direction) in 0), it can be expressed by the following expression (4).

[Equation 15] Further, the pressures inside and outside the cyclone separator 3 at the axial center of the cylindrical body 14 are also balanced, and the equation expressing this pressure balance is expressed by the following equation (5).

[Equation 16] Here, ΔP _t is the cyclone separator 3 (cylindrical body 1
4) The pressure loss [Pa] generated by the communication part 15 of the upper outlet, the swirl vane 25, the cap member 26, the flow paths 28, 29 (see FIG. 3), etc., and expressed by the following formula (6) as an example. To be done.

[Equation 17] Here, V _t is the outflow velocity [m / s] of the saturated steam S from the cyclone separator 3, and the saturated steam amount Q _s
Is calculated by dividing by the cross-sectional area S _s of the cylindrical body 14, and is expressed by the following equation (7).

[Equation 18] Further, ΔP _b is a pressure loss [Pa] caused by the communication passages 14a and 14b (see FIG. 3) at the lower outlet of the cyclone separator 3 (cylindrical body 14), and is represented by the following equation (8) as an example. It

[Formula 19] Here, V _b is the outflow velocity [m / s] of the saturated water W from the cyclone separator 3, and is represented by the following equation (9) similarly to the flow velocity V _{t of the} saturated steam.

[Equation 20] The following expression (10) is obtained from the above expressions (1) to (3).

[Equation 21] Further, by rearranging the equations (4) and (10), the following equation (11) is obtained.

[Equation 22] By rearranging the equation (5), the following equation (12) is obtained.

[Equation 23] By the way, the gas-liquid mixed fluid MX generated in the cylindrical body 14
The peripheral velocity (swirl velocity) at the point of radius r is proportional to the radius r because the gas-liquid mixed fluid MX is swirling as a forced vortex. Therefore, the peripheral speed V is expressed by the following equation (13).

[Equation 24] Here, since the peripheral velocity V _θ is the horizontal component of the inflow velocity of the gas-liquid mixed fluid MX, it is expressed by the following equation (14).

[Equation 25] Therefore, the above equations (12) and (13) are replaced by the above (11)
And the following equation (15) is obtained.

[Equation 26] Since this expression (15) is an expression representing the height z from the lower end of the cylindrical body 14 to the gas-liquid interface B at the point of the radius r,
The shape of the gas-liquid interface B is shown. Where gravitational acceleration g
And the inner diameter R are constants, and when the height H _w of the water surface L and the densities ρ _w and ρ _s are also treated as constants, the inflows Q _s and Q _w are obtained (determined) from the set values, and the formula is obtained. The shape (height) of the gas-liquid interface B can be calculated by obtaining the swirl velocity V _θ by (14) and the pressure losses ΔP _t and ΔP _b by the equations (6) to (9). Become. Further, when the height H _w of the water surface L cannot be treated as a constant, it can be obtained from the measured value by the water level sensor, the control target value, the design value, etc. as described above, and the density ρ _w and ρ _s can also be calculated from pressure and temperature. By substituting the equation (14) into the equation (15), the equation (1
6) is obtained.

[Equation 27] Here, the cross-sectional area S_iAnd the angle α (cos α) is a constant
It Therefore, using this equation (16),
Degree V_θInflow Q without_sAnd Q _wIf
Every, pressure loss ΔP_tAnd ΔP_bSubstituting directly
Thus, the shape of the gas-liquid interface B can be obtained. Na
In the above formula (16), "Q_s+ Q_wIs a gas-liquid mixture
Inflow quantity Q (= Q of the whole combined fluid MX_s+ Q_w) Represents
Therefore, the above equation (16) can also be calculated using the inflow amount Q.
it can. Furthermore, ΔP in equation (16)_tAnd ΔP_bExpression
By using the expressions substituting (6) to (9),
Force loss ΔP_tAnd ΔP_bInflow Q without
_sAnd Q_wBy directly substituting
You can ask for a condition. Of equations (15) and (16)
By substituting the inner diameter R of the cylindrical body 14 for the radius r,
As shown in equations (17) and (18) of
Height z of the outer edge of_RYou can also ask.

[Equation 28]

[Equation 29] In equation (18), pressure loss ΔP_tAnd ΔP_bIs
From the equations (6) to (9), the flow rate Q_sAnd Q_wof
Since it is a function, the height z_RIs the flow rate Q_sAnd Q_wStrange
It is a function of numbers. Therefore, the flow rate Q_sAnd Q_w
By adjusting the height z_RIs a predetermined value (even if
If the height H of the cylinder 14₀, Height H₀X%, etc.)
Can be controlled. As a result,
It is possible to prevent the mist contained in the water vapor S from increasing.
Wear. Similarly, the height z at the position of the radius r is also the flow rate Q_s
And Q_wCan be controlled by adjusting
It The equations (6) and (8) for calculating the pressure loss are
As an example, in general, the flow rate Q_s, Q_wAnd density ρ_s，
ρ_wΔP as a function of_t= F_t(Q_s, Ρ_s), ΔP _b=
f_b(Q_w, Ρ_w).

According to the present invention, the gas-liquid interface shape is calculated in consideration of the saturated water vapor pressure in the upper layer of the gas-liquid interface and the pressure loss when the saturated water vapor is discharged from the cyclone separator. A more accurate gas-liquid interface shape and position of the gas-liquid interface can be obtained. As a result, the position of the gas-liquid interface in the cyclone separator can be accurately controlled, so that it is possible to prevent an increase in the amount of mist due to the rise of the gas-liquid interface.

[Brief description of drawings]

1 (a) and 1 (b) are diagrams showing various symbols necessary for obtaining a liquid surface shape of a cyclone separator, respectively, in a horizontal cross-sectional view and a vertical cross-sectional view of the cyclone separator.

FIG. 2 is a schematic view of a steam drum, FIG. 2B is an external view of the steam drum as seen from above, and FIG. 2A is a schematic view of a cross section as seen from the direction A of FIG.

3A and 3B are schematic views of a cyclone separator provided in a steam drum, where FIG. 3A is a vertical sectional view and FIG. 3B is a horizontal sectional view.

[Explanation of symbols]

1 steam drum 2 Introductory pipe 3 cyclone separator 13 Cyclone section 14 cylinder 14a, 14b communication passage 23 Primary scrubber section W saturated water S saturated steam Water surface in L drum B gas-liquid interface

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidero Fukuda             3-5-1, 717-1, Fukahori-cho, Nagasaki-shi, Nagasaki             Hishi Heavy Industries Ltd. Nagasaki Research Center

Claims (7)

[Claims] 1. A gas-liquid mixture comprising saturated steam and saturated water.
The combined fluid flows in, and the inflowing gas-liquid mixed fluid is centrifuged.
Cyclone separator that separates into more saturated steam and saturated water
A method of calculating the shape of the gas-liquid interface in the data Upper pressure loss ΔP of the cyclone separator_tIn front
Per second of the saturated steam contained in the gas-liquid mixed fluid
Inflow Q_sAnd the density ρ of the saturated steam_sOn the basis of
The lower pressure loss ΔP of the cyclone separator_b
Per second of the saturated water contained in the gas-liquid mixed fluid
Inflow rate Q_wAnd the density ρ of the saturated water _wBased on
And swivel in the cyclone separator
Swirling velocity V of the outer peripheral portion of the gas-liquid mixed fluid_θThe gas-liquid mixture
Calculated based on the inflow of combined fluid, The gas-liquid interface of the cyclone separator is calculated by the following formula.
Find the shape, Calculation method of gas-liquid interface shape of cyclone separator. [Equation 1] Where z is from the center of the cylinder of the cyclone separator
From the lower end of the cylinder at the point of radius r to the gas-liquid interface
Height, g is gravitational acceleration, R is the cyclone separation
Inner diameter of cylinder, H_wIs the cylinder of the cyclone separator
Saturated water outside the cyclone separator from the bottom of the
The height to the surface of the water. 2. The cyclone separator according to claim 1, wherein the pressure loss coefficient of the upper portion of the cyclone separator is σ _t , and the cylindrical cross-sectional area of the cyclone separator is S _s , the upper pressure loss P _t is _calculated by the following equation. A method for calculating the gas-liquid interface shape of the separator. [Equation 2] 3. An apparatus according to claim 1 or 2, the pressure loss coefficient of the bottom of the cyclone separator sigma _b, the cylindrical cross-sectional area of the cyclone separator and S _s, calculated by the following formula said lower pressure loss P _b , Calculation method of gas-liquid interface shape of cyclone separator. [Equation 3] 4. The gas-liquid mixed fluid according to claim 1, wherein the gas-liquid mixed fluid is tangential to the outer peripheral portion of the cylinder of the cyclone separator and with respect to a plane perpendicular to the axis of the cylinder. A method of calculating the gas-liquid interface shape of the cyclone separator, which flows in through an introduction pipe connected at an angle α and obtains the swirling speed by the following formula. [Equation 4] Here, S _i is the cross-sectional area of the introduction pipe. 5. A tubular body having a cylindrical shape, wherein the introduction pipe is the tubular body.
Tangential to the outer periphery of the cylinder and with respect to the axis of the cylinder
It is connected at an angle α to the vertical plane and flows through the inlet pipe.
Gas-liquid mixed fluid consisting of saturated steam and saturated water
Is separated into saturated steam and saturated water by centrifugation.
By the method of calculating the shape of the gas-liquid interface in the cron separator
There Upper pressure loss ΔP of the cyclone separator_tIn front
Per second of the saturated steam contained in the gas-liquid mixed fluid
Inflow Q_sAnd the density ρ of the saturated steam_sOn the basis of
The lower pressure loss ΔP of the cyclone separator_b
Per second of the saturated water contained in the gas-liquid mixed fluid
Inflow rate Q_wAnd the density ρ of the saturated water _wBased on
Because The gas-liquid interface of the cyclone separator is calculated by the following formula.
Find the shape, Calculation method of gas-liquid interface shape of cyclone separator. [Equation 5] Where z is the radius r from the center of the cylinder
Height from the lower end of the cylinder to the gas-liquid interface, g is gravity acceleration
Degree, R is the inner diameter of the cylinder, H_wIs from the bottom of the cylinder to the front
The height of saturated water outside the cyclone separator to the surface of the water
S,_iIs the cross-sectional area of the introduction tube. 6. A gas-liquid mixture comprising saturated steam and saturated water.
The combined fluid flows in, and the inflowing gas-liquid mixed fluid is centrifuged.
Cyclone separator that separates into more saturated steam and saturated water
This is a method to calculate the height of the outer peripheral portion of the gas-liquid interface in the data
hand, The upper pressure loss ΔPt of the cyclone separator is
Per second of the saturated steam contained in the gas-liquid mixed fluid
Inflow Q_sAnd the density ρ of the saturated steam_sOn the basis of
The lower pressure loss ΔP of the cyclone separator_b
Per second of the saturated water contained in the gas-liquid mixed fluid
Inflow rate Q_wAnd the density ρ of the saturated water _wBased on
And swivel in the cyclone separator
Swirling velocity V of the outer peripheral portion of the gas-liquid mixed fluid_θThe gas-liquid mixture
Calculated based on the inflow of combined fluid, The gas-liquid interface of the cyclone separator is calculated by the following formula.
Perimeter height z_RAsk, Calculation of the height of the outer periphery of the gas-liquid interface of the cyclone separator
Method. [Equation 6] Where g is gravitational acceleration, H_wIs the cyclone separe
From the bottom of the cylinder of the data to the outside of the cyclone separator
It is the height of saturated water up to the surface of the water. 7. A tubular body having a cylindrical shape, wherein the introduction pipe is the tubular body.
Tangential to the outer periphery of the cylinder and with respect to the axis of the cylinder
It is connected at an angle α to the vertical plane and flows through the inlet pipe.
Gas-liquid mixed fluid consisting of saturated steam and saturated water
Is separated into saturated steam and saturated water by centrifugation.
Calculate the height of the outer periphery of the gas-liquid interface in the cron separator
Method, Upper pressure loss ΔP of the cyclone separator_tIn front
Per second of the saturated steam contained in the gas-liquid mixed fluid
Inflow Q_sAnd the density ρ of the saturated steam_sOn the basis of
The lower pressure loss ΔP of the cyclone separator_b
Per second of the saturated water contained in the gas-liquid mixed fluid
Inflow rate Q_wAnd the density ρ of the saturated water _wBased on
Because The gas-liquid interface of the cyclone separator is calculated by the following formula.
Perimeter height z_RAsk, Calculation of the height of the outer periphery of the gas-liquid interface of the cyclone separator
Method. [Equation 7] Where g is gravitational acceleration, H_wIs from the bottom of the cylinder to the front
The height of saturated water outside the cyclone separator to the surface of the water
S,_iIs the cross-sectional area of the introduction tube.