CN111102832A

CN111102832A - A kind of multi-layer mesh belt kiln for denitration catalyst calcination and mesh belt kiln control system

Info

Publication number: CN111102832A
Application number: CN201911274188.8A
Authority: CN
Inventors: 梁燕; 徐辉; 童翠香; 梁斌华; 高昇
Original assignee: Anhui Yuanchen Environmental Protection Science and Technology Co Ltd
Current assignee: Anhui Yuanchen Environmental Protection Science and Technology Co Ltd
Priority date: 2019-12-12
Filing date: 2019-12-12
Publication date: 2020-05-05

Abstract

The invention discloses a multi-layer mesh belt kiln for denitration catalyst calcination, comprising a mesh belt kiln body, a material transmission mechanism for conveying materials into the furnace body, and a ventilation and exhaust system; the mesh belt kiln body comprises a plurality of interconnected Each modular unit includes an outer steel plate, a full-fiber folded block lining, a furnace frame, a full-fiber folded block lining and an inner steel plate stacked in sequence; the mesh belt kiln furnace body sequentially includes a heating section along the material conveying direction. , constant temperature section and cooling section, and at least one exhaust gas outlet is provided on the furnace top of the heating section and constant temperature section; the material transmission mechanism is fixed at the bottom of the mesh belt kiln body, and the mesh belt of the material transmission mechanism is laid at least more than one layer of catalyst. The invention also discloses a control system of a multi-layer mesh belt kiln for denitration catalyst calcination. The advantages of the present invention are that the production capacity is increased, the energy saving and consumption are effectively reduced, and the production cost is reduced.

Description

Denitration catalyst is calcined with multilayer guipure kiln and guipure kiln control system

Technical Field

The invention relates to the field of mesh belt kilns, in particular to a multilayer mesh belt kiln for denitration catalyst calcination and a mesh belt kiln control system.

Background

The mesh belt kiln belongs to a continuous production kiln, is widely applied to ceramic glass and chemical industry, and is mainly used for drying or firing products. The traditional mesh belt kiln heats the lower part or the upper part and the lower part of a mesh belt, materials are laid on a conveying mesh belt and are in a static state relative to the conveying mesh belt, and the mesh belt moves forwards at a constant speed to pass through the kiln. Generally, in order to pursue productivity, the material stacking thickness is about 40mm, so that the material is easily heated unevenly, the phenomenon of half-grown occurs, and the uniformity of the product quality is influenced. If the thickness of the material is reduced, the length of the mesh belt kiln needs to be increased to meet the capacity requirement, so that the equipment cost is greatly increased and the operation cost is increased.

Chinese patent CN105202911A discloses a mesh belt kiln, the mesh belt kiln body includes a drying section, a firing section and a cooling section. Because the height of the inner cavity of the furnace body of the existing mesh belt kiln is smaller, only one layer of catalyst can be paved in the kiln during each calcination, and because the mesh belt kiln occupies a large area, the production space is greatly wasted, the production cost is invisibly increased, and meanwhile, the catalyst calcination efficiency cannot be improved. Chinese patent CN 206192108U discloses a catalyst roasting double-layer mesh belt furnace for natural gas heating chemical industry, which is mainly provided with a double-layer mesh belt, and a driving mechanism consists of a driving motor, a reduction transmission mechanism, a matched chain wheel combination, a driving roller combination and a driven roller. The closed circulation systems are respectively divided into an upper layer and a lower layer. The double-layer mesh belt is driven by two independent transmission mechanisms, and the upper and lower layers of closed circulation systems are independent respectively, so that the energy consumption is high, and the production cost is increased.

Disclosure of Invention

The invention aims to solve the technical problem of providing a multilayer mesh belt kiln for denitration catalyst calcination, which can improve the utilization rate of the mesh belt kiln, effectively improve the productivity and reduce the production cost.

The invention solves the technical problems through the following technical means:

a multi-layer mesh belt kiln for calcining a denitration catalyst comprises a mesh belt kiln body, a material conveying mechanism for conveying materials into the kiln body and a ventilation system; the mesh belt kiln body comprises a plurality of module units which are arranged in a stacked mode and connected, and each module unit comprises an outer steel plate, a full-fiber folding block lining, a furnace body frame, a full-fiber folding block lining and an inner steel plate which are sequentially arranged in a stacked mode from outside to inside; the mesh belt kiln body sequentially comprises a temperature rising section, a constant temperature section and a cooling section along the material conveying direction, and at least one waste gas discharging port is formed in each of furnace tops of the temperature rising section and the constant temperature section;

the material transmission mechanism is fixedly arranged at the bottom of the furnace body of the mesh belt furnace, and at least more than one layer of catalyst is laid on a mesh belt of the material transmission mechanism; compared with the prior art, the material containing height of the furnace body of the mesh belt kiln is increased, only one layer of catalyst can be paved on the material transmission mechanism in the prior art, more than two layers of catalysts can be paved on the material transmission mechanism, and the productivity can be effectively improved; the invention is characterized in that the inner side and the outer side of a furnace body frame are respectively provided with a full-fiber folding block lining, and the full-fiber folding block lining has the properties of high temperature resistance, light weight and automatic absorption of expansion stress.

Preferably, the ventilation and exhaust system comprises an exhaust gas exhausting mechanism and a kiln tail end cooling mechanism; the waste gas discharging mechanism is arranged on the furnace top of the temperature rising section, and the furnace tail end cooling mechanism is arranged on the furnace top of the cooling section; the waste gas exhaust mechanism comprises at least one waste gas exhaust fan and a waste gas exhaust pipe; each waste discharge fan is correspondingly arranged at the waste discharge air outlet, the fan inlets of the waste discharge fans are communicated with the inner part of the mesh belt kiln body, and the fan outlets of the waste discharge fans are communicated with the exhaust air pipe; the exhaust air pipe comprises an exhaust main pipe and a plurality of exhaust branch pipes connected to the exhaust main pipe.

Preferably, each of the module units has a length of 2 m; the number of the module units is 26, and the module units are connected through bolts; the module units are connected through bolts, so that the self thermal expansion stress of the furnace body frame structure can be effectively eliminated, and the disassembly is convenient.

Preferably, the pipe diameter of the exhaust main pipe is

The pipe diameter of the exhaust main pipe is

The pipe diameter of the main exhaust pipe is

Compared with the prior art, the method is increased to meet the emission requirement of the sulfur ammonia substances.

Preferably, the furnace tops of the temperature raising section and the calcining section are also provided with electric heating pipes. The operating power of the electric heating pipe is 3.0kw-3.5kw, and the operating power of the electric heating pipe is correspondingly increased according to the increase of the height of the furnace body so as to meet the requirement of the calcination temperature of the multilayer catalyst.

Preferably, the material of the full-fiber folding block lining is high-temperature-resistant ceramic fiber; the high-temperature ceramic fiber has the advantages of high temperature resistance, light weight, low heat conductivity coefficient, small heat accumulation, good thermal shock resistance, automatic expansion stress absorption and the like, and by using the structure, the kiln can be directly started in a cold state without controlling the temperature rising/reducing speed like the traditional refractory brick lining structure, so that the kiln drying time can be saved, and the energy consumption can be reduced.

Preferably, the material conveying mechanism comprises a driving mechanism, a feeding rack, a discharging rack, a mesh belt supporting mechanism and a mesh belt; the feeding rack is arranged at the inlet end of the kiln, and the discharging rack is arranged at the outlet end of the kiln; the driving mechanism comprises a power assembly, a driving roller combination and a driven roller; the power assembly comprises a driving motor fixedly arranged at the bottom of the feeding rack and a chain wheel combination which is matched with the driving motor and fixedly arranged at the bottoms of the feeding rack and the discharging rack; the driving roller combination is fixedly arranged on the tail end discharging rack; the driven roller is arranged on the feeding end rack;

the mesh belt supporting mechanism comprises spacing carrier rollers fixedly arranged in the furnace, and a bearing carrier roller and a belt returning carrier roller part fixedly arranged outside the furnace; the mesh belt is laid on the mesh belt supporting mechanism.

Preferably, at least three layers of the carrier rollers are laid; the invention meets the load of the catalyst weight by increasing the number of layers of the carrier roller.

Preferably, a fan inlet of the waste discharge fan is of an inclined structure along the material conveying direction; in the process of material conveying, waste gas generated by calcination can move along with airflow generated by conveying, and the inlet of the fan for discharging waste gas is arranged into a structure inclined along the material conveying direction, so that the waste gas can enter the fan at an inclined angle while flowing, and the inlet of the fan can be prevented from being blocked by scaling.

The invention also provides a control system of the multilayer mesh belt kiln for calcining the denitration catalyst, wherein an output shaft of the driving motor is coaxially connected with a frequency converter; the frequency converter detects the output speed of the driving motor, inputs a signal into the microcomputer control system, and controls the microcomputer control system to output a control signal to control and adjust the output speed of the driving motor; the invention sets the proportional relation of the period and the frequency on the microcomputer control system, the transmission period can be automatically changed as long as the frequency is changed, and the transmission speed detection feedback device is additionally arranged on the site, so that the actual operation period can be conveniently measured;

a thermocouple is arranged at each module unit, the thermocouple collects the temperature of each module unit and inputs a temperature signal into a microcomputer control system, and the microcomputer control system outputs a control signal to control the conduction current of the three-phase silicon controlled module to control the heat productivity of the resistance wire;

a pneumatic valve is arranged at the outlet of the waste exhaust fan, and a pressure transmitter is fixedly arranged on the exhaust main pipe of the exhaust air pipe; the pressure transmitter detects the air pressure in the exhaust main pipe and inputs a detected air pressure signal into the microcomputer control system, and the microcomputer control system outputs a control signal to control the frequency converter to adjust the output speed of the driving motor, so that the main pipe pressure of the flue gas extracted by the kiln is controlled and stabilized.

Further, the parameter detection of the frequency converter, the thermocouple and the pressure transmitter comprises the following steps:

s1, measuring the transmission speed of a transmission belt of the mesh belt kiln, reading the data detected by the frequency converter, measuring once a day, and calculating the whole roasting time;

s2, reading the temperature of the thermocouple at each point, comparing the read value with a standard temperature curve, and measuring 8-10 times per day with the same interval time; changing the set temperature of the heater if the measured value does not meet the standard value;

s3, reading the exhaust static pressure on the recorder, measuring 8-10 times every day, wherein the interval time is the same; and if the standard value is not met, adjusting the pneumatic valve.

The invention has the advantages that:

1. compared with the prior art, the material containing height of the furnace body of the mesh belt kiln is increased, only one layer of catalyst can be paved on the material transmission mechanism in the prior art, and at least more than one layer of catalyst can be paved on the material transmission mechanism in the invention, so that the productivity can be effectively improved; the invention is characterized in that the inner side and the outer side of a furnace body frame are respectively provided with a full-fiber folding block lining, and the full-fiber folding block lining has the properties of high temperature resistance, light weight and automatic absorption of expansion stress.

2. The module units are connected through bolts, so that the self thermal expansion stress of the furnace body frame structure can be effectively eliminated, and the disassembly is convenient; the exterior steel plate is of a shutter structure, so that heat dissipation is facilitated, and the whole body is attractive and elegant.

3. The pipe diameter of the main exhaust pipe is

4. According to the invention, the operation power of the electric heating pipe is correspondingly increased according to the increase of the height of the furnace body, so as to meet the requirement of the calcination temperature of the multilayer catalyst.

5. The invention meets the load of the catalyst weight by increasing the number of layers of the carrier roller.

6. In the process of material conveying, waste gas generated by calcination can move along with airflow generated by conveying, and the inlet of the fan for discharging waste gas is arranged into a structure inclined along the material conveying direction, so that the waste gas can enter the fan at an inclined angle while flowing, and the inlet of the fan can be prevented from being blocked by scaling.

Drawings

FIG. 1 is a schematic structural diagram of a multi-layer mesh belt kiln for calcining a denitration catalyst according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a modular unit of a mesh belt kiln body according to an embodiment of the invention;

FIG. 3 is a schematic structural diagram of a temperature rising section of a furnace body of a mesh belt kiln according to an embodiment of the invention;

FIG. 4 is a schematic structural diagram of a constant temperature section of a mesh belt kiln body according to an embodiment of the invention;

FIG. 5 is a schematic structural diagram of a cooling section of a furnace body of a mesh belt kiln according to an embodiment of the invention;

FIG. 6 is a schematic structural diagram of a control system of a multi-layer mesh belt kiln for calcining a denitration catalyst according to an embodiment of the present invention;

the reference numbers illustrate:

1. a mesh belt kiln body; 101. a module unit; 1011. an outer steel plate; 1012. a full fiber folded block liner; 1013. a furnace body frame; 1014. an inner steel plate; 1015. a thermocouple; 11. a temperature rising section; 12. a constant temperature section; 13. a cooling section; 14. a waste gas discharge port; 2. a material conveying mechanism; 21. a drive mechanism; 22. a feeding frame; 23. a discharging machine frame; 24. a mesh belt supporting mechanism; 25. a mesh belt; 26. a frequency converter; 3. ventilating an exhaust system; 31. an exhaust gas discharging mechanism; 311. a waste discharge fan; 3111. a pneumatic valve; 312. an exhaust air duct; 3121. a pressure transmitter; 32. a cooling mechanism at the tail end of the kiln; 4. and a control microcomputer control system.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

As shown in fig. 1, the present embodiment discloses a multilayer mesh belt kiln for calcining a denitration catalyst, which specifically uses the orientation of fig. 1 as a reference, and comprises a mesh belt kiln body 1, a material conveying mechanism 2 for conveying materials into the kiln body, and an air ventilation and exhaust system 3.

As shown in fig. 1 and 2, the furnace body 1 of the mesh belt kiln comprises a plurality of module units 101 arranged in a stacked manner, each module unit 101 comprises an outer steel plate 1011, a full fiber folding block lining 1012, a furnace body frame 1013, a full fiber folding block lining 1012 and an inner steel plate 1014 which are arranged in a stacked manner from outside to inside in sequence, and the outer steel plate 1011, the full fiber folding block lining 1012, the furnace body frame 1013, the full fiber folding block lining 1012 and the inner steel plate 1014 are fixed by adopting anchoring parts between every two of them; the mesh belt kiln body 1 sequentially comprises a temperature rising section 11, a constant temperature section 12 and a cooling section 13 along the material conveying direction.

As shown in fig. 3 and 4, at least one exhaust port 14 is provided on each of the furnace roofs of the temperature raising section 11 and the constant temperature section 12.

As shown in fig. 1, the material conveying mechanism 2 is installed at the bottom of the mesh belt kiln body 1 through bolts; the ventilation and exhaust system 3 comprises a waste gas exhaust mechanism 31 and a kiln tail end cooling mechanism 32; the waste gas exhausting mechanism 31 is installed on the furnace top of the temperature rising section 11 through bolts, and the furnace tail end cooling mechanism 32 is installed on the furnace top of the cooling section 13 through bolts.

As shown in fig. 3, 4 and 5, the material conveying mechanism 2 includes a driving mechanism 21, a feeding frame 22, a discharging frame 23, a mesh belt supporting mechanism 24 and a mesh belt 25; 22 the feeding frame is arranged at the inlet end of the kiln through bolts, and the discharging frame 23 is arranged at the outlet end of the kiln through bolts; the driving mechanism 21 comprises a power assembly, a driving roller combination and a driven roller;

the power assembly comprises a driving motor arranged at the bottom of the feeding rack 22 through a bolt and a chain wheel combination which is matched with the driving motor and arranged at the bottoms of the feeding rack 22 and the discharging rack 23 through bolts; the driving roller combination is arranged on the tail end discharging rack 23 through a bolt; the driven roller is arranged on the feeding frame 22 through a bolt, and the mesh belt supporting mechanism 24 comprises an interval carrier roller arranged in the furnace through a bolt, and a bearing carrier roller and a belt returning carrier roller part which are fixedly arranged outside the furnace; the mesh belt 25 is laid on the mesh belt supporting mechanism 24; and the distance between the upper surface of the mesh belt 25 and the inner top of the mesh belt kiln body 1 is 670-680 mm;

as shown in fig. 1 to 4, the exhaust mechanism 31 includes at least one exhaust fan 311 and an exhaust air duct 312; each waste discharge fan 311 is correspondingly arranged at the waste discharge port 14 through a bolt, the fan inlets of the waste discharge fans 311 are communicated with the inside of the mesh belt kiln body 1, and the fan outlets of the waste discharge fans 311 are communicated with the exhaust air pipe 312; the waste discharge fan 311 is a variable frequency fan; the exhaust stack 312 includes an exhaust main pipe and a plurality of exhaust branch pipes connected to the exhaust main pipe. The type of the exhaust fan 311 of the invention is a 9-26-5D-2-18.5kw variable frequency fan.

Preferably, the material of the full fiber folded block liner 1012 is high temperature resistant ceramic fiber. The traditional structure is built by adding refractory bricks and refractory soil, a newly-built furnace needs to be subjected to a furnace baking process before use, a long time is needed for removing moisture brought by construction, sintering to form a whole body and eliminating the internal stress and expansion problem, and the high-temperature resistant ceramic fiber material is adopted as the lining 1012 of the full-fiber folding block, so that the high-temperature resistant mesh belt kiln has the advantages of high temperature resistance, light weight, low heat conductivity coefficient, small heat storage, good thermal shock resistance and capability of automatically absorbing the expansion stress, and can be directly started for use under the cold condition.

The starting end of the exhaust air pipe 312 is provided with a cold air mixing electric regulating valve; through the setting of doping cold wind electrical control valve, can regulate and control and mix the reasonable emission area that the cold wind volume comes to control ammonium bisulfate material.

According to the invention, the waste discharge fan 311 is set as a variable frequency fan, so that the waste discharge pressure and the fan variable frequency control can be adjusted according to specific conditions in the actual operation process, and waste materials can be cleaned in time.

A control system of a multilayer mesh belt kiln for calcining a denitration catalyst is characterized in that an output shaft of a driving motor is coaxially connected with a frequency converter 26; the frequency converter 26 detects the output speed of the driving motor, and inputs the signal into the microcomputer control system 4, and controls the microcomputer control system 4 to output a control signal to control and adjust the output speed of the driving motor; the invention sets the proportional relation of the period and the frequency on the microcomputer control system 4, the transmission period can be automatically changed as long as the frequency is changed, and the transmission speed detection feedback device is additionally arranged on the site, thereby being convenient for measuring the actual operation period;

a thermocouple 1015 is arranged at each module unit 101, the thermocouple 1015 collects the temperature of each module unit 101 and inputs a temperature signal into the microcomputer control system 4, and the microcomputer control system 4 outputs a control signal to control the conduction current of the three-phase silicon controlled module to control the heating value of the resistance wire;

a pneumatic valve 3111 is arranged at the fan outlet of the exhaust fan 311, and a pressure transmitter 3121 is fixedly arranged on the exhaust main pipe of the exhaust air pipe 312; the pressure transmitter 3121 detects the wind pressure in the exhaust main pipe, and inputs the detected wind pressure signal into the microcomputer control system 4, the microcomputer control system 4 outputs a control signal to control the frequency converter 26 to adjust the output speed of the driving motor, thereby controlling and stabilizing the main pipe pressure of the kiln for extracting the flue gas; by setting the exhaust fan 311 as a variable frequency fan, the exhaust pressure and the fan variable frequency control can be adjusted according to specific conditions in the actual operation process, and then the waste can be cleaned in time.

Further, the parameter detection of the frequency converter 26, the thermocouple 1015 and the pressure transmitter 3121 includes the following steps:

s1, measuring the transmission speed of a transmission belt of the mesh belt kiln once a day, and calculating the whole roasting time;

s2, reading the temperature of the temperature recorder at each point, comparing the read value with a standard temperature curve, and measuring 8 times per day with the same interval time; changing the set temperature of the heater if the measured value does not meet the standard value;

s3, reading the exhaust static pressure on the recorder, measuring 8 times every day, wherein the interval time is the same; if the standard value is not met, the pneumatic valve 3111 is adjusted.

The single layer catalyst was placed on the mesh belt 25 of this example and the temperatures of the 26 modular units of the single layer catalyst calcined in the kiln are shown in table 1.

Table 1 shows the calcination temperature results for each module unit 101 for the catalyst calcination of example 1.

The working principle of the embodiment is as follows: the present invention provides a multi-layer mesh belt kiln for calcining a denitration catalyst, the catalyst of the present invention is placed on the mesh belt 25 of the mesh belt kiln, in which case the catalyst should be arranged in the parallel direction of the running of the mesh belt 25. In this step, all conditions, such as temperature, residence time, amount of catalyst loading and exhaust flow rate, are tightly controlled. The calcined catalyst exiting the exit of the mesh belt kiln was stacked on pallets, allowing them to cool simultaneously. The calcined catalysts must be handled with care because they lack elasticity and are more brittle than the dried products. The mesh belt kiln is provided with several exhaust ducts 312 on its top wall, and exhausts exhaust gas such as steam, ammonia gas, sulfur oxides, and ammonium sulfate gas generated from a catalyst precursor to the air through an exhaust fan 311. Since the flow rate of the gas discharged from each exhaust gas pipe seriously affects the activity of the catalyst, it must be strictly controlled individually. The mesh belt kiln also has a plurality of curtain walls on the top, and the inner end is provided with a brick partition, which divides the space above the catalyst on the mesh belt into a plurality of parts, thereby leading fresh air to circulate through the catalyst holes. All exhaust gases were treated using a bag house.

Compared with the prior art, the invention has the following advantages: firstly, the material containing height of the furnace body 1 of the mesh belt kiln is increased compared with the prior art, only one layer of catalyst can be paved on the material transmission mechanism 2 in the prior art, at least more than one layer of catalyst can be paved on the material transmission mechanism 2, and the productivity can be effectively improved; the traditional structure is built by adding refractory bricks and refractory soil, a newly-built furnace needs to be subjected to a furnace baking process before use, a longer time is needed for removing moisture brought by construction, sintering to form a whole body and eliminating the internal stress and expansion problem, the full-fiber folding block lining 1012 is arranged on the inner side and the outer side of a furnace body frame, and the full-fiber folding block lining 1012 has the properties of high temperature resistance, light weight and capability of automatically absorbing expansion stress, so that the mesh belt kiln can be directly started for use under the cold condition, the furnace baking time can be saved, the productivity is improved, the energy can be effectively saved, the consumption is reduced, and the production cost is reduced. Secondly, the module unit 101 is connected through bolts, so that the self thermal expansion stress of the furnace body frame structure can be effectively eliminated, and the disassembly is convenient; the exterior steel plate 1011 is of a shutter structure, so that heat dissipation is facilitated, and the whole body is attractive and elegant. Thirdly, the mesh belt kiln body 1 adopts a multi-point extraction centralized discharge mode, so that waste gas discharged during the production of the kiln can be fully discharged, and hot air of the kiln is not excessively extracted.

Example two

As shown in fig. 1 and fig. 2, the difference between the present embodiment and the first embodiment is that the mesh belt kiln body 1 of the present invention is composed of 26 module units 101 connected by bolts, each module unit 101 has a length of 2m, and the module units 101 are connected by bolts, so that the self thermal expansion stress of the frame structure of the furnace body can be effectively eliminated, and the disassembly is convenient.

The pipe diameter of the main exhaust pipe is

The pipe diameter of the main exhaust pipe is

The pipe diameter of the main exhaust pipe is

The furnace tops of the temperature rising section 11 and the calcining section 12 are also provided with electric heating pipes, and the operating power of the electric heating pipes is 3.0kw-3.5 kw; according to the invention, the operation power of the electric heating pipe is correspondingly increased according to the increase of the height of the furnace body, so as to meet the requirement of the calcination temperature of the multilayer catalyst.

The carrier rollers are at least paved with three layers; the invention meets the load of the catalyst weight by increasing the number of layers of the carrier roller.

Preferably, the blower inlet of the waste discharge blower 311 of the present invention is an inclined structure along the material conveying direction; in the process of material conveying, waste gas generated by calcination moves along with airflow generated by conveying, and the inlet of the waste gas exhaust fan 311 is arranged in a structure inclined along the material conveying direction, so that the waste gas can flow and enter the fan at an inclined angle, and scaling and blockage at the inlet of the fan can be avoided.

The temperature of 26 module units calcined in the kiln for the double-layer catalyst placed on the mesh belt 25 of this example is shown in table 2.

EXAMPLE III

The difference between the embodiment and the above embodiment is that an aluminum silicate fiber blanket is also arranged in a gap formed between the furnace top and the furnace wall of the mesh belt furnace body 1 of the invention, and the aluminum silicate fiber blanket can play a role of sealing by being tightly plugged and compacted.

The weight of the top of the furnace top of the mesh belt kiln body 1 acts on the kiln top steel beam through the hanging piece, the bottom of the kiln is covered with the corrugated steel plate, the weight of the side wall of the kiln and the weight of the bottom of the kiln are uniformly transmitted to the bottom cross beam of the kiln through the bottom steel plate, and the whole structure is reasonable in stress and simple in structure.

Reasonable expansion gaps and treatment measures are arranged between the furnace body frames of each module unit 101 so as to avoid the influence of thermal expansion on the whole structure.

The temperature of 26 module units of the double-layer catalyst calcined in the kiln is shown in table 3.

Table 3 calcination temperature results for each module unit of the catalyst calcination of example 3

Example four

The embodiment is different from the embodiment, because the waste of heat energy of the kiln and the temperature difference are caused due to the overlarge air draft, in order to fully discharge waste gas discharged during the production of the kiln and not excessively extract hot air of the kiln, 18 extraction openings are arranged on the top of the heating section 11 and the constant temperature section 12 of the mesh belt kiln body 1, and the extraction openings can be flexibly adjusted according to the production requirement. Each fan cover and each dotted extraction pipeline are provided with an adjusting flashboard, so that the suction force of each section can be flexibly adjusted, and the set requirement can be effectively met. The exhaust air duct 312 is made of 304 stainless steel. The exhaust branch pipe 316L of the temperature rising section 11 is made of stainless steel and the low temperature section 304 is made of a fan cover.

The invention also provides a movable cleaning port for the part of the exhaust air pipe 312 which is easy to be blocked by sulfur and ammonia. The flange connection is arranged at the position needing to be cleaned frequently, the external heat insulation layer is arranged reasonably, and the damage and the influence on the external heat insulation structure during cleaning are reduced.

EXAMPLE five

The present embodiment differs from the above embodiments in that: in order to reduce the influence of cold air leaked from two ends of the kiln on a product under the condition of air draft as much as possible, shielding curtains are arranged at the kiln inlet end and the kiln outlet end of a mesh belt kiln body 1, wherein the inlet end is 2 channels, the outlet end is 1 channel, and the shielding curtains are made of soft refractory fibers. The shutter and the bottom temperature zone partition wall in the kiln play a role in controlling the airflow in the kiln, thereby playing a role in controlling the temperature. Particularly, in the heating section 11 of the SCR denitration catalyst product, due to the spontaneous combustion characteristic of volatile substances, the heating rate and the air inlet amount of the section need to be strictly controlled, otherwise, the internal spontaneous combustion and over-temperature scrapping of the product can be caused. The device is reasonably improved and designed through practical application in the past engineering, and the requirement of reasonable control is effectively met. The material of the kiln top adjusting gate plate is 316L material.

EXAMPLE six

The driving motor adopts a domestic high-quality brand speed reducing motor 14 KW distribution variable speed gear box mechanism, adopts variable frequency speed regulation, is connected with a computer control system, can effectively control the running speed of the kiln mesh belt 25 within 33 +/-1 hours of roasting period, has the precision within +/-1 percent, runs stably, has low failure rate, and can ensure long-term running.

The main driving roller adopts a rubber sleeve roller with the diameter of 630mm (12mm wear-resistant rubber, can resist the temperature of 120 ℃, diamond patterns are engraved on the rubber, and the friction force is increased); the wrap angle roller is phi 400 mm; a phi 300mm supporting and adjusting roller and a phi 219mm pressing roller; the driving roller is subjected to external glue casting treatment, the wrap angle of the mesh belt 25 and the roller is increased by adjusting the wrap angle to compress the roller, the friction coefficient of the mesh belt 25 and the roller is increased, and the transmission efficiency is improved.

The driven roller is arranged on the feeding frame 22 and consists of a phi 630mm twill roller and a fixed roller. The driven roller is connected with a matched roller adjusting mechanism, and the tensioning and deviation rectifying functions of the mesh belt 25 are completed by adjusting the linear strokes of two sides of the roller.

The feeding frame 22 is arranged at the inlet section of the kiln, and is 3000mm long and 2520mm wide. The tension device is formed by welding and assembling profile steel, is firmly welded with a basic embedded part, and plays a role in bearing the running tension of the driven roller and the mesh belt 25. Related adjusting parts and detection control parts of the driven roller are organically combined in the frame, and a protective net is covered to ensure the operation safety.

The discharging frame 23 is arranged at the outlet end of the kiln. The length is 3000mm, and the width is 2520 mm. The tension device is formed by welding and assembling profile steel, is firmly welded with a basic embedded part, and plays a role in bearing the running tension of the main driving roller and the mesh belt 25. The driving roller combination and related adjusting components and detection control components are organically combined in the frame, and the outer cover is provided with a protective mesh belt 25 to ensure the operation safety. The main driving mechanism is arranged on the side part of the frame and is connected with the main driving roller through a chain wheel combination.

The mesh belt is made of 316L stainless steel. The flat mesh belt 25 is formed by a combined balanced symmetrical weaving method, and the penetrating strips are

Is wound with a wire of

The pitch is 12.5mm, the pitch is 25mm, and the width is 1700 mm. The flatness is +/-2 mm, the mesh belt 25 can be guaranteed to effectively load materials, and the reasonable conduction of the temperatures of the upper layer and the lower layer of the mesh belt 25 is guaranteed.

The roller material is respectively set to be 321 stainless steel material and 304 stainless steel material according to different temperatures, and both the materials are high-quality stainless steel pipe processing. The configuration is 3 roots/M.

The mesh belt conveyor idler is arranged at the bottom of the kiln, bears the weight through a support fixed at the bottom of the kiln, and is configured to be a carbon steel metal idler with phi 57mm horizontally arranged at intervals of 1.0M.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. a multi-layer mesh belt kiln for denitration catalyst calcination is characterized in that: comprising a mesh belt kiln furnace body, a material transmission mechanism and a ventilation and exhaust system for conveying materials to the furnace body; the mesh belt kiln furnace body includes A plurality of interconnected modular units, each of which includes an outer steel plate, a full-fiber folded block lining, a furnace frame, a full-fiber folded block lining and an inner steel plate sequentially stacked from outside to inside; the mesh The furnace body of the belt kiln sequentially includes a heating section, a constant temperature section and a cooling section along the material conveying direction, and at least one exhaust gas outlet is provided on the furnace top of the heating section and the constant temperature section;

The material transmission mechanism is fixedly arranged at the bottom of the mesh belt kiln body, and at least one layer of catalyst is laid on the mesh belt of the material transmission mechanism.

2. The multi-layer mesh belt kiln for denitration catalyst calcination according to claim 1, characterized in that: the ventilation and exhaust system comprises a waste gas exhaust mechanism and a kiln tail end cooling mechanism; the exhaust gas mechanism is arranged on the is located on the furnace roof of the heating section, and the cooling mechanism at the rear end of the kiln is arranged on the furnace roof located in the cooling section; the exhaust gas mechanism includes at least one exhaust fan and an exhaust air duct; each The exhaust fans are correspondingly installed at the exhaust ports, the fan inlets of the multiple exhaust fans are communicated with the interior of the mesh belt kiln body, and the fan outlets of the multiple exhaust fans are all communicated with the exhaust air pipe; the exhaust air pipe includes an exhaust main pipe and a plurality of exhaust branch pipes connected to the exhaust main pipe.

3 . The multi-layer mesh belt kiln for denitration catalyst calcination according to claim 1 , wherein the length of each of the modular units is 2 m; the number of the modular units is 26. 4 .

4 . The multi-layer mesh belt kiln for calcining a denitration catalyst according to claim 1 , wherein the furnace tops of the heating section and the calcining section are also provided with electric heating pipes. 5 .

5. The multi-layer mesh belt kiln for calcining a denitration catalyst according to claim 1, wherein the pipe diameter of the exhaust main pipe is

The diameter of the exhaust main pipe is

6 . The multi-layer mesh belt kiln for denitration catalyst calcination according to claim 1 , wherein the material of the inner lining of the all-fiber folded block is high temperature resistant ceramic fiber. 7 .

7 . The multi-layer mesh belt kiln for denitration catalyst calcination according to claim 1 , wherein the material transmission mechanism comprises a drive mechanism, a feeding rack, a discharging rack, a mesh belt support mechanism and a mesh belt. 8 . belt; the feeding frame is arranged at the inlet end of the kiln, and the discharging frame is arranged at the outlet end of the kiln; the driving mechanism includes a power assembly, a driving roller combination and a driven roller; the power The assembly includes a driving motor fixedly arranged at the bottom of the feeding frame, and a sprocket assembly matched with the driving motor and fixedly arranged at the bottom of the feeding frame and the discharging frame; the driving roller combination is fixedly arranged at the bottom of the feeding frame and the discharging frame. on the discharge frame at the tail end; the driven roller is arranged on the frame at the feed end;

The mesh belt supporting mechanism includes spacer rollers fixed inside the furnace, bearing rollers and belt-returning rollers fixed outside the furnace; the mesh belt is laid on the mesh belt support mechanism.

8 . The multi-layer mesh belt kiln for denitration catalyst calcination according to claim 7 , wherein the idler rollers are laid with at least three layers. 9 .

9 . The multi-layer mesh belt kiln for calcining a denitration catalyst according to claim 1 , wherein the fan inlet of the waste exhaust fan is an inclined structure along the material conveying direction. 10 .

10. A control system based on the multi-layer mesh belt kiln for denitration catalyst calcination according to any one of claims 1-9, characterized in that: a frequency converter is coaxially connected to the output shaft of the drive motor; the The inverter detects the output speed of the drive motor, and inputs the signal into the microcomputer control system, and controls the output control signal of the microcomputer control system to control and adjust the output speed of the drive motor;

Each of the module units is provided with a thermocouple. The thermocouple collects the temperature of each module unit and inputs the temperature signal into the microcomputer control system. The microcomputer control system outputs a control signal to control the conduction of the three-phase thyristor module. current to control the heat generation of the resistance wire;

The fan outlet of the exhaust fan is provided with a pneumatic valve, and a pressure transmitter is fixed on the exhaust main pipe of the exhaust air pipe; the pressure transmitter detects the wind pressure in the exhaust main pipe and transmits the The detected wind pressure signal is input into the microcomputer control system, and the microcomputer control system outputs the control signal to control the frequency converter to adjust the output speed of the drive motor, thereby controlling and stabilizing the main pressure of the flue gas extracted from the kiln.

11. The control system of a multi-layer mesh belt kiln for calcining a denitration catalyst according to claim 10, wherein the parameter detection of the frequency converter, the thermocouple and the pressure transmitter comprises the following steps:

S1. Measure the transmission speed of the conveyor belt of the mesh belt kiln, read the data detected by the inverter, measure it once a day, and calculate the entire roasting time;

S2. Read the temperature of the thermocouple at each point, and compare the read value with the standard temperature curve. Measure 8-10 times a day with the same interval each time; if the measured value does not meet the standard value, then Change the set temperature of the heater;

S3. Read the exhaust static pressure on the recorder and measure it 8-10 times a day with the same interval each time; if it does not meet the standard value, adjust the pneumatic valve.