CN202506603U - Variable-cross section bending torsion movable blade rotary coal powder separator - Google Patents

Abstract

The utility model relates to the field of coal powder separators, in particular to a variable-cross section bending torsion movable blade rotary coal powder separator. The variable-cross section bending torsion movable blade rotary coal powder separator consists of a separator shell, guide stationary blades, a movable blade frame, rotor movable blades, a coal falling pipe, a conical baffle plate and a powder return pipe. The guide stationary blades are the conventional straight blades which are uniformly distributed on the outer circle of the top of the powder return pipe and are fixed on the separator shell; the rotor movable blades are variable-cross section bending torsion blades which are uniformly distributed on the movable blade frame of an inner circle; the coal falling pipe is positioned in the center of the separator shell; and the conical baffle plate is arranged on the lower parts of the rotor movable blades and are butted with the bottom sides of the lower parts of the rotor movable blades in a matched way. According to the variable-cross section bending torsion movable blade rotary coal powder separator, the design of the variable cross sections of the rotor movable blades is low in resistance loss, the electric consumption of separation can be reduced conveniently, and the separation efficiency of the separator can be improved under the blasting action generated by bending torsion design; and a rotor is low in rotation speed, so that the energy consumption of a motor can be reduced.

Description

A rotary pulverized coal separator with curved and twisted blades with variable cross-section

technical field

The utility model relates to the field of coal powder separators, in particular to a rotary coal powder separator with variable section curved and twisted blades. the

Background technique

At present, in order to meet the needs of coal types, load changes and low NO _X burner operation, the medium-speed mills of general pulverization systems are mostly equipped with static and moving blade combined rotary coal separators. The rotary pulverized coal separator is an important part of the pulverizing system, and its operating performance directly affects the safe and economical operation of the pulverizing system and the entire unit. Due to the fixity of the guide vane and the rotor vane type of the existing static and movable vane combined rotary coal separator, it is necessary to improve the operation performance of the separator by changing the combination of the static and movable vane installation and the rotating speed of the rotor vane , which will not only make the installation of the rotary pulverized coal separator complicated and cumbersome, but also increase the energy consumption of the motor virtually; the existing static and moving blade combined rotary pulverized coal separator cannot achieve high separation efficiency under low energy consumption , the increase of its separation efficiency will definitely lead to the increase of its energy consumption. The latest research on the new curved and twisted blade type rotary coal powder separator does not consider the actual thickness of the rotor moving blade, and does not optimize its structure, so the research on the rotary coal powder separator with higher separation efficiency under low energy consumption The optimal structure has become a hot topic of research.

Contents of the invention

In order to solve the problems that the existing rotary pulverized coal separator cannot achieve higher separation efficiency under low energy consumption and the uncertainty of the optimal structure of the rotary pulverized coal separator with curved and twisted blades, the utility model provides a The actual thickness of the moving blade, a new type of rotary pulverized coal separator with gradual design of the cross-section of the inlet section of the steam inlet side and the outlet section of the steam outlet side of the rotor moving blade, and an optimized design of its structure. the

The technical solution adopted to solve the above problems is as follows:

The rotary pulverized coal separator is composed of a separator shell, guide vane, moving vane frame, rotor vane, coal drop pipe, conical baffle and powder return pipe. The guide vane is a traditional straight blade, evenly distributed in the return The outer ring on the top of the powder pipe is fixed on the separator shell; the rotor blades are curved and twisted blades with variable cross-section, which are evenly distributed on the blade frame of the inner ring; the coal falling pipe is located in the center of the separator shell; The plate is arranged at the lower part of the rotor blade, and is mated and docked with the bottom edge of the lower part of the rotor blade. the

The four arcs AG, AH, CK, and CL of the variable section on the steam inlet side of the rotor blade, and the four arcs BI, BJ, DM, and DN on the variable section on the steam outlet side have different radii of curvature. the

The curvature radii of the curved arc AB and arc CD in the rotor blade are not equal. the

The upper top angle B of the internal steam outlet side of the rotor blade and the lower bottom angle C of the outer steam inlet side are both twisted towards the center of the rotor blade, which reduces the blocking loss when the pulverized coal airflow enters and the airflow when it flows out. The eddy current loss greatly reduces the resistance loss, which helps to reduce the separation power consumption of the separator. the

The rotor blades have a camber of 15° and a torsion angle of 25°

Both the steam inlet side AC and the steam outlet side BD of the rotor blade are straight lines. the

The horizontal installation angle γ∈[0,45°] of the guide vane; the horizontal installation angle α∈[0,45°] and the vertical installation angle β∈[0,45°] of the rotor blade. the

The horizontal installation angle of the rotor blades is 10°. the

The beneficial effects of the utility model are:

The utility model considers the actual thickness of the rotor blade of the rotary coal powder separator, and gradually changes the section of the inlet section of the steam inlet side and the outlet section of the steam outlet side, so that the rotating coal can be rotated at a lower motor speed. The pulverized coal at the outlet of the powder separator is finer, the separation performance is higher, and the resistance loss is lower, thereby improving the safety and economy of the pulverization system, the boiler and the entire unit, and playing an important role in the energy saving and consumption reduction of the power plant; its bend The determination of the optimal structure of the twisted rotor blade provides a new method for the design and manufacture of the rotary pulverized coal separator. the

Description of drawings

Fig. 1 is the overall structural representation of the utility model;

Figure 2 is a schematic structural view of the rotor blade;

Figure 3 is a top view of the section of the rotor blade after bending and twisting;

Figure 4 is a sectional view of the middle cross section of the guide vane and the rotor vane;

Fig. 5 is a partial enlargement of Y in Fig. 4 and a schematic diagram of the installation of the horizontal installation angles γ and α of the guide vane and the rotor vane;

Fig. 6 is a schematic diagram of installation of the vertical installation angle β of rotor blades. the

Labels in the figure:

1-separator shell; 2-guide vane; 3-moving blade frame; 4-rotor moving blade; 5-coal drop pipe 6-conical baffle; 7-powder return pipe. the

OO' is the centerline of the axis of rotation;

h is the length of the rotor blade;

d is the width of the rotor blade before bending;

δ is the thickness of the rotor blade;

A, B, C, D are the four vertices of the rotor blade;

AC is the steam inlet side of the rotor blade;

BD is the steam outlet side of the rotor blade;

The arcs AG, AH, CK, and CL are the four arcs of the variable section section on the inlet steam side of the rotor blade;

Arcs BI, BJ, DM, and DN are four arcs of the variable section section on the outlet steam side of the rotor blade;

γ is the horizontal installation angle of the guide vane;

α is the horizontal installation angle of the rotor blade;

β is the vertical installation angle of rotor blades. the

Detailed ways

The utility model provides a rotary pulverized coal separator with variable cross-section curved and twisted blades. The utility model will be further described below in conjunction with the accompanying drawings and specific embodiments. the

As shown in FIG. 1 , this embodiment consists of a separator housing 1 , guide vane 2 , moving vane frame 3 , rotor moving vane 4 , coal drop pipe 5 , conical baffle 6 and powder return pipe 7 . The guide vane 2 is a traditional straight vane, which is evenly distributed on the outer ring at the top of the powder return pipe 7 and fixed on the separator housing 1; On the frame 3 ; the coal drop pipe 5 is located at the center of the separator housing 1 ; the conical baffle 6 is arranged at the lower part of the rotor blade 4 and matched with the lower bottom edge of the rotor blade 4 . the

As shown in Fig. 2 and Fig. 3, the rotor blade 4 of the rotary pulverized coal separator according to this embodiment considers the actual thickness of the blade, and the cross-section of the inlet section on the steam inlet side and the outlet section on the steam outlet side of the blade is gradually changed. The specific implementation process of the transformation of the rotor blade 4 from the traditional straight blade to the curved and twisted blade with variable cross-section is as follows:

1) Thickness: select a cuboid straight blade whose length is h, width is d, and height (thickness of the blade) is δ;

2) Variable cross-section: select the midpoint of the four thickness sides of the straight cuboid blade, denoted as A, B, C, D; select G, I, H, J, K, M in turn on the four width sides of the cuboid straight blade, Eight points F and N are sequentially connected to AG, AH, CK, CL, BI, BJ, DM, DN; make arcs AG, AH, CK, CL, BI, BJ, DM, DN, and their curvature radii are R ₁ ~R ₈ , and the values of each curvature radius R _x are different (where x is a natural number ∈ [1, 8]); connecting AC and BD, the face AHJBDNLC, the face AGIBDMKC, the face AGIBJH and the face CKMDNL form a variable cross-section tetrahedron;

3) Bending: Always keep AC and BD as straight lines, and bend the straight blade of variable cross-section tetrahedron in a longitudinal arc. The radius of curvature of arc AB is R ₉ , the radius of curvature of arc CD is R ₁₀ , and R ₉ and R ₁₀ The values are not equal;

4) Torsion: First, keep the positions of the three vertices A, C, and D on the curved blade with variable cross-section unchanged, and keep the side BD always as a straight line, so that the upper vertex B of the internally measured steam outlet side is directed toward the rotor blade 4 The center is twisted; on the basis of the completion of the twisting of the top angle B of the upper part of the steam outlet side, the positions of the three vertices A, B, and D on the variable-section curved and twisted blade are kept unchanged, and the side AC is always kept as a straight line, so that the outer side enters The bottom corner C of the steam side is twisted toward the center of the rotor blade 4 . the

The horizontal installation angle γ∈[0,45°] of the guide vane 2; the horizontal installation angle α∈[0,45°] of the rotor blade 4, and the vertical installation angle β∈[0,45°]; the rotor blade 4 The value range of the camber is [0, 45°]; the value range of the torsion angle of the rotor blade 4 is [0, 45°]. the

The definition of the horizontal installation angle γ of the guide vane 2: combined with Fig. 5, γ is the vane width PQ of the guide vane 2 in the middle cross-sectional view, the end point P of the inner steam outlet side of the guide vane 2 and the centerline of the rotation axis The included angle (acute angle) of the line OP connecting the projected point O of OO'. the

The definition of the vertical installation angle β of the rotor rotor blade 4: combined with Figure 6, take the center point E of the surface AGIBJH and the center point F of the surface CKMDNL, and connect the two center points EF, then the line where EF is located and the centerline of the rotation axis OO′ The included angle (acute angle) is the vertical installation angle β of rotor blade 4. the

The definition of the horizontal installation angle α of the rotor blade 4: combined with Fig. 5, on the basis of the determination of the vertical installation angle β of the rotor blade 4, a plane passing through the midpoint of EF and perpendicular to the centerline OO′ of the rotation axis is drawn. The projection point of the intersection point of the plane and the center line OO' of the rotating shaft is point O, and the projection point of the intersection point of the intersection point with the AC and BD sides of the rotor blade 4 are points A' and B' respectively, then the line OB' and the line B'A' The included angle (acute angle) is the horizontal installation angle α of the rotor blade 4 . the

The definition of the camber of the rotor blade 4: combined with Figure 2, the angle between the steam inlet side and the steam outlet side of the curved rotor blade (4) (that is, the dotted line blade) and the initial variable cross-section straight blade’s steam inlet side and steam outlet side . the

The definition of the torsion angle of the rotor blade 4: combined with Figure 2, the upper top angle B of the inner steam outlet side of the rotor blade (4) and the lower bottom angle C of the outer steam inlet side are twisted towards the center of the rotor blade (4) Angle. the

Through theoretical analysis and simulation tests, it can be seen that the utility model not only considers the actual thickness of the rotor blade 4 of the rotary pulverized coal separator, but also gradually changes the cross-section of the inlet section of the steam inlet side and the outlet section of the steam outlet side. Under the condition of constant ventilation of the system, the optimal structure of the rotor vane of the separator is 15°, the torsion angle is 25°, and the horizontal installation angle is 10°. Compared with the traditional straight-blade rotary pulverized coal separator , the flow field distribution is relatively uniform, which is mainly reflected in the uniformity of velocity distribution and pressure distribution; the rotor speed of the separator is relatively reduced by 22%; the fineness of pulverized coal at the outlet is reduced by 18.7%; the comprehensive separation efficiency is increased by 1.43%; The ventilation resistance of the phase field is reduced by 194Pa. The utility model considers the actual thickness of the rotor blade 4 of the rotary pulverized coal separator, and gradually changes the cross-section of the inlet section of the steam inlet side and the outlet section of the steam outlet side, so that the rotary pulverized coal separator can be operated at a lower motor speed. The outlet pulverized coal is finer, the separation performance is higher, and the resistance loss is lower, thus improving the safety and economy of the pulverizing system, the boiler and the entire unit, and playing an important role in the energy saving and consumption reduction of the power plant; the bending of the rotary pulverized coal separator The determination of the optimal structure of the twisted rotor blade provides a new method and theoretical basis for the design and manufacture of the separator. the

Claims (8)

1. A rotary pulverized coal separator with variable cross-section curved and twisted blades, which consists of a separator housing (1), a guide vane (2), a blade frame (3), a rotor blade (4), and a coal drop pipe (5), composed of a conical baffle (6) and a powder return pipe (7), characterized in that the guide vane (2) is a traditional straight blade, evenly distributed on the outer ring of the top of the powder return pipe (7) and fixed On the separator housing (1); the rotor blades (4) are curved and twisted blades with variable cross-section, evenly distributed on the inner ring blade frame (3); the coal drop pipe (5) is located in the separator housing (1) ) center; the conical baffle (6) is arranged at the lower part of the rotor blade (4), and is matched with the lower bottom edge of the rotor blade (4). 2. A rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 1, characterized in that the four arcs AG and AH of the variable cross-section section on the steam inlet side of the rotor blade (4) are , CK, CL, the four arcs BI, BJ, DM, and DN of the variable section section on the outlet steam side have different radii of curvature. 3. A rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 1, characterized in that the curvature radii of the curved arc AB and arc CD in the rotor blade (4) are different from each other. wait. 4. A rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 1, characterized in that, the upper apex angle B of the inner steam outlet side of the rotor blade (4) and the outer inlet The bottom bottom angle C of the steam side is all twisted to the center of the rotor blade (4). 5. The rotary pulverized coal separator with curved and twisted blades with variable cross-section according to claim 4, characterized in that the rotor blade (4) has a curvature of 15° and a twist angle of 25°. 6 . The rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 1 , wherein the steam inlet side AC and the steam outlet side BD of the rotor blade ( 4 ) are both straight lines. 7. A rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 1, 2, 3, 4 or 5, characterized in that the horizontal installation angle γ∈ of the guide vane (2) [0, 45°]; the horizontal installation angle α∈[0,45°] of the rotor blade (4), and the vertical installation angle β∈[0,45°]. the 8. The rotary pulverized coal separator with variable cross-section curved and twisted blades according to claim 7, characterized in that the horizontal installation angle of the rotor blades (4) is 10°. the

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