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CN-121631059-B - Air root valve, rotary kiln and necking air quantity adjusting method

CN121631059BCN 121631059 BCN121631059 BCN 121631059BCN-121631059-B

Abstract

The invention belongs to the technical field of valves. A root valve, rotary kiln and method for regulating the air quantity of necking down are disclosed. The air root valve comprises a valve body, an air channel cavity for air flow circulation is arranged in the valve body, the upper part of the air channel cavity is communicated with the decomposing furnace, the lower part of the air channel cavity is communicated with the smoke chamber, the air root valve is characterized in that the valve body is connected with a driving mechanism, the telescopic part of the driving mechanism is connected with the connecting frame, the movable wall is arranged on the connecting frame, one end of the movable wall stretches into the air duct cavity and regulates and controls ventilation quantity through horizontal movement, and the height of the movable wall is greater than or equal to 500 mm. The invention solves the problem that the existing movable plate or movable block is easy to generate turbulent flow when being adjusted, overcomes the defect that the adjustable movable plate or movable block damages a flow field, realizes the wind tunnel effect and ensures the lifting effect on raw meal.

Inventors

  • LI WEIHUA

Assignees

  • 山东司德伯重型装备有限公司

Dates

Publication Date
20260508
Application Date
20260204

Claims (13)

  1. 1. The air root valve comprises a valve body, an air channel cavity for flowing air flow is arranged in the valve body, the upper part of the air channel cavity is communicated with a decomposing furnace, the lower part of the air channel cavity is communicated with a smoke chamber, The wind root valve is arranged at a necking position between a smoke chamber and a decomposing furnace of the rotary kiln, the valve body is connected with the driving mechanism, the telescopic part of the driving mechanism is connected with the connecting frame, the movable wall is arranged on the connecting frame, one end of the movable wall stretches into the air duct cavity and regulates and controls ventilation quantity through horizontal movement, the height of the movable wall is more than or equal to 500 mm, the movable wall is formed by pouring two refractory materials, the main body material at one side connected with the connecting frame is a material with higher strength and certain heat resistance, the main body material at one side close to the air duct cavity is a material with higher heat resistance and certain strength, and different parts of the movable wall are adapted to different working conditions through double-material layering design; The valve body comprises a plurality of clamping frames, each clamping frame is provided with a horizontal channel for the connecting frame and the movable wall to pass through, a fixed column is arranged between the adjacent clamping frames, and the clamping frames are detachably connected with the supporting frames of the fixed columns; an upper balance wheel set and a lower guide wheel set are connected in the horizontal channel of the clamping frame, the upper balance wheel set is in contact with the upper part of the connecting frame, the lower guide wheel set is in contact with the bottom of the connecting frame, and the upper balance wheel set is used for balancing the falling force of the movable wall so that the movable wall keeps horizontally moving in the air channel cavity; The valve body is characterized by further comprising an outer cover, the outer cover is connected to the outer side of the valve body, the driving mechanism comprises a driving motor and a transmission unit, the driving motor is connected to the outer side of the outer cover, the transmission unit is arranged in a transmission box inside the outer cover, the driving motor is connected with the transmission unit, and the transmission unit is used for controlling the movable wall to horizontally move under the driving of the driving motor.
  2. 2. The wind root valve of claim 1, wherein the wind root valve is configured to, The upper balance wheel set comprises a plurality of balance wheels which are arranged side by side, the balance wheels are connected with a balance wheel base through a wheel frame, a core seat cavity is formed in the balance wheel seat, a disc spring core seat is arranged in the core seat cavity, a disc spring is sleeved on the disc spring core seat, one end of the disc spring is connected with the disc spring core seat, and the other end of the disc spring is connected with the wheel frame; the upper part of the core seat cavity is provided with a threaded hole, the compression bolt passes through the threaded hole and then contacts with the top of the disc spring core seat to compress the disc spring core seat, the balance wheel base is provided with a positioning seat, the wheel frame is rotationally connected with the positioning seat through a rotating shaft, the positioning seat is positioned at the front part of the advancing direction of the movable wall, and the core seat cavity is positioned at the rear part of the advancing direction of the movable wall.
  3. 3. The wind root valve of claim 1, wherein the wind root valve is configured to, The fixed column is provided with at least one cleaning hole, a sealing cover is sealed on the cleaning hole, and the sealing cover is installed on a supporting frame of the fixed column through a hinging rod.
  4. 4. The wind root valve of claim 1, wherein the wind root valve is configured to, The support frame of the fixed column is connected with a vertical sealing framework, and a flexible sealing material is arranged on the vertical sealing framework for vertical sealing between the movable wall and the fixed column when the movable wall moves; The upper part of the air channel cavity is connected with a first flange used for being connected with the decomposing furnace, and the lower part of the air channel cavity is connected with a second flange used for being connected with the smoke chamber; the clamping frame is connected with a horizontal sealing framework, and a flexible sealing material is arranged on the horizontal sealing framework and used for horizontally sealing the movable wall with the first flange and the second flange when the movable wall moves.
  5. 5. The wind root valve of claim 4, wherein, When the connecting frame and the movable wall are disassembled for overhauling, the horizontal sealing framework between the first flange and the movable wall is used for arranging and supporting the protection beam to form an overhauling space.
  6. 6. The wind root valve of claim 1, wherein the wind root valve is configured to, The movable wall is a rectangular movable wall or an arc movable wall.
  7. 7. The wind root valve of claim 1, wherein the wind root valve is configured to, The transmission case is provided with a cooling air inlet and a cooling air outlet, and the transmission case is communicated with cooling air through the cooling air inlet so as to cool the transmission unit.
  8. 8. The wind root valve of claim 1, wherein the wind root valve is configured to, The transmission unit comprises a driving shaft, a driving sprocket, a first transmission chain, a second transmission chain, a first driven sprocket, a second driven sprocket, a first driving screw, a second driving screw, a first driving nut and a second driving nut, wherein the first driving screw and the second driving screw are symmetrically arranged on two sides of the driving shaft; The driving shaft is connected with the driving motor, the driving sprocket is sleeved and fixed on the driving shaft, the first transmission chain is respectively in transmission connection with the driving sprocket and a first driven sprocket of a first driving screw rod, and the second transmission chain is respectively in transmission connection with the driving sprocket and a second driven sprocket of a second driving screw rod; The first driving screw is in threaded connection with the first driving screw, the second driving screw is in threaded connection with the second driving screw, the first driving screw is in rotary connection with a first bearing in the transmission case, and the second driving screw is in rotary connection with a second bearing in the transmission case.
  9. 9. The wind root valve of claim 8, wherein the wind root valve, The wind root valve further comprises an automatic lubrication system, the automatic lubrication system comprises a lubrication pump, the lubrication pump performs intermittent lubrication of the first bearing and the second bearing when the movable wall moves through the first pipeline, and the lubrication pump performs real-time lubrication of the first driving nut and the second driving nut when the movable wall moves through the second pipeline.
  10. 10. A rotary cement kiln comprising at least a decomposing furnace, a smoke chamber and the air root valve of any one of claims 1-9, wherein the upper part of the air root valve is connected with the decomposing furnace, and the bottom of the air root valve is connected with the smoke chamber.
  11. 11. A rotary kiln comprising at least a preheater and a root valve according to any one of claims 1 to 9, the root valve being connected to the bottom of the preheater.
  12. 12. A method for adjusting the air quantity of a necking, which is characterized by using the air root valve according to any one of claims 1-9 and comprising the following steps: According to the rated working condition of the cement rotary kiln production line, the movable wall is adjusted to an initial position, so that the air duct cavity forms an initial ventilation sectional area suitable for the rated flue gas flow rate; Continuously collecting key parameters of a cement kiln, setting a reference threshold value of each key parameter according to a standard stable state by taking a flow field state corresponding to a raw meal decomposition rate greater than or equal to a set threshold value, a kiln reaching sintering temperature and rated yield as the standard stable state, and dynamically comparing the parameters collected in real time with the corresponding reference threshold values; When the key parameter is monitored to deviate from the reference threshold value, calculating the required ventilation sectional area adjustment quantity according to the parameter deviation quantity, further generating a movable wall adjustment instruction, and determining the moving direction and the moving distance; when the deviation between each key parameter and the corresponding threshold value is smaller than the set threshold value, the ventilation air quantity in the kiln is judged to be reasonable at the moment, and the wind speed in the air channel cavity can effectively lift the raw meal; when the deviation of any key parameter from the corresponding threshold value is larger than the set threshold value, the fact that turbulence is larger at the moment is judged, the wind speed in the air duct cavity cannot effectively lift raw meal, a fine adjustment instruction is sent out according to deviation data fed back in real time, and the driving mechanism drives the movable wall to carry out set amplitude displacement correction until the deviation of each key parameter from the corresponding threshold value is smaller than the set threshold value.
  13. 13. The method for adjusting the air quantity of a necking in claim 12, wherein, The key parameters of the cement kiln are collected, and at least comprise the flow rate of flue gas in the air channel cavity, the pressure difference between the decomposing furnace and the flue chamber, the negative pressure value in the decomposing furnace, the raw meal supply quantity and fineness and the combustion temperature in the decomposing furnace.

Description

Air root valve, rotary kiln and necking air quantity adjusting method Technical Field The invention relates to the technical field of valves, in particular to an air root valve, a rotary kiln and a necking air quantity adjusting method. Background The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art. In the cement pre-decomposition production process, a decomposing furnace is core equipment for decomposing raw materials. The internal core reaction process is that the combustion of the pulverized coal releases heat to provide energy for the decomposition of raw material powder (CaCO 3 is the main component), and the raw material powder needs to be decomposed into CaO and CO 2 in a heat absorption way under the high-temperature environment of about 850 ℃. From the aspect of process control requirements, the decomposition rate of the raw meal powder needs to reach 95% or more, and the subsequent sintering quality of the clinker can be ensured. The raw meal powder in the decomposing furnace is moved and reacted in a definite technological path, after the raw meal powder from the upper preheater enters the decomposing furnace, the raw meal powder is driven by the suction effect of a high-temperature fan at the kiln tail, the lifting effect of smoke at the bottom of the decomposing furnace in a smoke chamber of the rotary kiln and the rotational flow effect of tertiary air to move upwards in a suspending way, and the decomposing reaction is completed in the process, and the decomposed raw meal powder is collected by the final preheater and enters the smoke chamber of the rotary kiln and the subsequent sintering process. The shrinkage port connecting the smoke chamber of the rotary kiln and the decomposing furnace is a key component for ensuring smooth promotion of the process, and has the core functions of serving as a channel for the smoke entering the decomposing furnace after combustion of the rotary kiln, and simultaneously realizing two main core targets by maintaining proper smoke flow rate and stable flow field in the channel, namely, the smoke entering the decomposing furnace from high temperature and fully exchanging heat by a preheating system, and the raw meal entering the decomposing furnace is lifted to ensure full suspension decomposition in the furnace, and the raw meal not decomposed in the decomposing furnace is prevented from directly flowing back into the smoke chamber of the rotary kiln. If the raw meal powder directly enters the smoke chamber of the rotary kiln, the raw meal powder enters the rotary kiln along with air flow to absorb heat again for decomposition, so that the stability of the firing temperature in the kiln can be damaged, the quality of clinker is further affected, and serious production accidents can be caused. In the theoretical level, stable raw material quantity and fineness, stable pulverized coal combustion state in the furnace and stable negative pressure distribution of the decomposing furnace are preconditions for maintaining the stability of the flow field at the necking position and guaranteeing the function realization. However, in the actual operation process of the cement industrial production line, the key parameters are in a dynamic fluctuation state, even have short-time large-amplitude fluctuation, the raw material quantity and fineness entering the decomposing furnace are difficult to continuously stabilize, the combustion state of the pulverized coal in the furnace is continuously changed under the influence of factors such as fuel quality, supply quantity and the like, and the negative pressure distribution in the decomposing furnace also fluctuates. In recent years, in response to industry calls such as carbon emission reduction and waste digestion, cement enterprises successively adopt new processes such as burning alternative fuel, garbage and dangerous waste in the decomposing furnace, and increasing bypass ventilation, so that fluctuation amplitude of working conditions in the decomposing furnace is further increased, and a greater challenge is brought to flow field stability at a necking position. When the flow rate of flue gas in the necking is too low or the necking structure cannot adapt to the change of working conditions, the blocking and lifting effects of the necking structure on raw meal can be obviously weakened, and the risk that the undegraded raw meal is directly connected into the kiln is very easy to occur under the dynamic working condition. The smoke chamber necking device adopted in the current industrial production generally has the problems that the installation mode is single, the connecting structure is fixed and not adjustable, when the calcination working condition is unreasonable and needs to be adjusted, the smoke chamber necking device must be stopped for maintenance or reconstruction, the operation difficulty is high, the adjustme