阅读说明：本技术 一种烘干系统、控制方法和沥青拌和站 (Drying system, control method and asphalt mixing station ) 是由 刘晓东 王晨 李�灿 于 2021-07-08 设计创作，主要内容包括：本发明公开了一种烘干系统、控制方法和沥青拌和站,包括冷料配料仓、进料缓冲仓、烘干滚筒、燃烧器、除尘器、引风机、烟囱；冷料配料仓与烘干滚筒之间通过传送机构连接进料缓冲仓；燃烧器设置于烘干滚筒的一侧；引风机与烘干滚筒之间通过气力管道连接所述除尘器；引风机的出风口连接烟囱；进料缓冲仓内设置冷骨料温度传感器及湿度传感器；烘干滚筒的出料口设置热骨料温度传感器；除尘器内设置负压传感器；除尘器与烘干滚筒之间的气力管道内设置烟气温度传感器；烟囱上设置烟气成分传感器。本发明将烘干系统作为一个整体进行调控,实现拌和站整个烘干系统参数自动化分段控制、精准施策、实时匹配。(The invention discloses a drying system, a control method and an asphalt mixing station, comprising a cold burden proportioning bin, a feeding buffer bin, a drying roller, a burner, a dust remover, an induced draft fan and a chimney; the cold material proportioning bin and the drying roller are connected with a feeding buffer bin through a conveying mechanism; the burner is arranged at one side of the drying roller; the induced draft fan and the drying roller are connected with the dust remover through a pneumatic pipeline; an air outlet of the induced draft fan is connected with a chimney; a cold aggregate temperature sensor and a humidity sensor are arranged in the feeding buffer bin; a discharge port of the drying roller is provided with a thermal aggregate temperature sensor; a negative pressure sensor is arranged in the dust remover; a flue gas temperature sensor is arranged in a pneumatic pipeline between the dust remover and the drying roller; the chimney is provided with a smoke component sensor. The invention regulates and controls the drying system as a whole, and realizes the automatic sectional control, accurate strategy and real-time matching of the parameters of the whole drying system of the mixing station.)

1. A drying system is characterized by comprising a cold burden proportioning bin, a feeding buffer bin, a drying roller, a burner, a dust remover, an induced draft fan and a chimney;

the cold burden proportioning bin is connected with the drying roller through a conveying mechanism;

the burner is arranged on one side of the drying roller;

the induced draft fan and the drying roller are connected with the dust remover through a pneumatic pipeline;

the air outlet of the induced draft fan is connected with the chimney;

a cold aggregate temperature sensor and a humidity sensor are arranged in the feeding buffer bin;

a discharge hole of the drying roller is provided with a thermal aggregate temperature sensor;

a negative pressure sensor is arranged in the dust remover;

a flue gas temperature sensor is arranged in a pneumatic pipeline between the dust remover and the drying roller;

and a smoke component sensor is arranged on the chimney.

2. The drying system of claim 1, wherein said conveyor is a belt conveyor.

3. A control method of a drying system according to claim 1 or 2, characterized in that the method comprises:

after the output of the mixing station is preset, starting an induced draft fan and starting a motor of the cold burden proportioning bin;

monitoring cold aggregate temperature and humidity, hot aggregate temperature and flue gas temperature, increasing the rotating speed of a motor of a cold aggregate proportioning bin, increasing a burner accelerator along with the increase of the rotating speed of the motor of the cold aggregate proportioning bin, and increasing an induced draft fan air door along with the increase of the burner accelerator until the preset yield reaches 80%;

monitoring the components of the flue gas, calculating the ratio of CO/CO2, and generating an optimal air-oil ratio curve of 80-100% of a preset yield by adjusting an air door of a combustor;

and the generated optimal air-oil ratio curve is adopted to monitor the temperature of the hot aggregate, the rotating speed of a motor of the proportioning bin and the change of the humidity parameter of the cold aggregate, so that the mixing station can stably produce and automatically regulate and control under low oil consumption.

4. The control method of claim 3, wherein the method of monitoring the temperature and humidity of the cold aggregate, the temperature of the hot aggregate and the temperature of the flue gas, increasing the rotating speed of a motor of the cold burden proportioning bin, increasing a burner throttle along with the increase of the rotating speed of the motor of the cold burden proportioning bin, and increasing an induced draft fan throttle along with the increase of the burner throttle until the preset yield reaches 80% comprises the following steps:

after the temperature and the humidity of the cold aggregate are monitored, the rotating speed of a motor of the cold aggregate batching bin is increased;

monitoring whether the temperature of the hot aggregate and the temperature of the flue gas are higher than a maximum set value or not;

if the temperature of the hot aggregate or the temperature of the flue gas is higher than the maximum set value, the rotating speed of a motor of the cold burden proportioning bin is continuously increased;

if the hot aggregate temperature and the flue gas temperature are not higher than the maximum set value, the detected aggregate temperature and the detected aggregate humidity are used as input conditions for calculation, the throttle of the combustor is increased in proportion along with the increase of the rotating speed of the motor of the cold aggregate proportioning bin, and the air door of the induced draft fan is increased in proportion along with the increase of the throttle of the combustor;

when the rotating speed of a motor of the cold burden proportioning bin is increased to 80% of the preset yield, stopping increasing the rotating speed of the motor, and detecting whether the temperature of hot aggregate or the temperature of flue gas reaches a maximum limit value at the moment;

if the temperature of the hot aggregate and the temperature of the flue gas do not reach the maximum limit value, the accelerator of the burner is continuously increased, and the air door of the induced draft fan is increased in proportion;

and if the temperature of the hot aggregate or the temperature of the flue gas reaches the maximum limit value, the accelerator of the burner stops increasing, and the air door of the induced draft fan stops increasing.

5. A control method according to claim 3 or 4, wherein the method of monitoring the flue gas composition and calculating the CO/CO2 ratio to generate an optimal air-oil ratio curve at 80% -100% of the preset production by adjusting the burner damper comprises:

reducing the air door of the induced draft fan until the dust removal negative pressure is lower than the minimum limit value;

detecting CO and CO2 components in the smoke and calculating a CO/CO2 ratio;

increasing the air door of the combustor according to a set proportion, and calculating the ratio of CO/CO 2;

if the ratio of CO/CO2 is reduced, the air door of the burner is increased according to a set proportion until the ratio of CO/CO2 is increased, and the optimal air door opening is set to be the air door opening before the ratio of CO/CO2 is increased;

if the ratio of CO/CO2 is increased, the air door of the burner is reduced according to a set proportion, and the ratio of CO/CO2 is calculated;

if the ratio is reduced, the air door of the combustor is continuously reduced according to the set ratio until the ratio of CO/CO2 is increased, the optimal air door opening is set to be the air door opening before the ratio of CO/CO2 is increased, and if the ratio is increased, the optimal air door opening is set to be the original opening;

gradually increasing the actual yield to 100% of the preset yield;

and generating the optimal air-oil ratio curve of the burner at the yield of 80% -100%.

6. A control method according to claim 5, characterized in that the method further comprises:

when the actual yield is less than 100% of the preset yield, increasing the rotating speed of a motor of the cold burden proportioning bin to increase the yield by 10%, and simultaneously increasing the accelerator of the combustor in proportion;

if the flue gas temperature or the hot aggregate temperature is lower than the limit value, the accelerator of the burner is continuously increased in proportion until the flue gas temperature or the hot aggregate temperature is not lower than the limit value, the components of CO and CO2 in the flue gas are continuously detected, and the ratio of CO/CO2 is calculated.

7. A control method according to claim 5, characterized in that said set proportion is 3%.

8. A control method as claimed in any one of claims 5 to 7, wherein the method of monitoring the changes in the parameters of hot aggregate temperature, proportioning bin motor speed and cold aggregate humidity using the generated optimum air-to-oil ratio curve comprises:

working by adopting the generated optimal wind-oil ratio curve;

when the temperature of the hot aggregate exceeds the limit value, proportionally increasing or reducing the accelerator of the burner until the temperature of the hot aggregate does not exceed the limit value;

when the rotating speed of a motor of the cold burden proportioning bin is increased or reduced by more than 5%, the throttle of the combustor is increased or reduced in proportion, and the temperature of hot aggregate is not beyond the limit value;

when the humidity of the cold aggregate is increased or reduced by more than 10%, the throttle of the burner is increased or reduced in proportion, and the temperature of the hot aggregate is ensured not to exceed the limit value.

9. A control method according to claim 8, characterized in that when the hot aggregate temperature is lower than the limit value, the burner throttle is increased; when the hot aggregate temperature is above the limit, the burner throttle is reduced.

10. An asphalt mixing station, characterized in that it is equipped with a drying system according to claim 1 or 2 or with a control method according to claims 3-9.

Technical Field

The invention relates to the technical field of road building machinery, in particular to a drying system, a control method and an asphalt mixing station.

Background

Along with the rapid development of domestic economy, infrastructure construction such as roads presents a situation of high-speed development, the demand on asphalt concrete mixing stations is increased day by day, the requirements on technical performance indexes of the asphalt concrete mixing stations are increased more and more based on the requirements on energy conservation, emission reduction and environmental protection, and higher requirements on the production quality, environmental protection, energy conservation and the like of the mixing stations are provided. The aggregate drying system is one of core systems of an asphalt mixing station, comprises a drying roller, a burner, a dust remover, an induced draft fan, a blower, a cold aggregate bin, corresponding pipelines, a conveying belt and other accessories, and is used for drying and heating cold aggregates to hot aggregates meeting production requirements, huge energy is consumed in the process, and the energy consumption of the whole mixing station is about more than 80%.

The mixing station drying system needs a long time from starting to reaching a preset yield and stabilizing production, parameter control in the period is completely dependent on experience of operators, the drying system is a whole system, and the heat exchange efficiency of the whole drying system is influenced by the change of parameters of one link.

Disclosure of Invention

The invention aims to provide a drying system, a control method and an asphalt mixing station, which realize automatic sectional control, accurate strategy and real-time matching of the parameters of the whole drying system of the mixing station.

The invention adopts the following technical scheme for realizing the aim of the invention:

the invention provides a drying system, which comprises a cold burden proportioning bin, a feeding buffer bin, a drying roller, a burner, a dust remover, an induced draft fan and a chimney;

the cold burden proportioning bin is connected with the drying roller through a conveying mechanism;

the burner is arranged on one side of the drying roller;

the induced draft fan and the drying roller are connected with the dust remover through a pneumatic pipeline;

the air outlet of the induced draft fan is connected with the chimney;

a cold aggregate temperature sensor and a humidity sensor are arranged in the feeding buffer bin;

a discharge hole of the drying roller is provided with a thermal aggregate temperature sensor;

a negative pressure sensor is arranged in the dust remover;

a flue gas temperature sensor is arranged in a pneumatic pipeline between the dust remover and the drying roller;

and a smoke component sensor is arranged on the chimney.

Further, the conveying mechanism is a belt conveying mechanism.

The invention provides a control method, which comprises the following steps:

after the output of the mixing station is preset, starting an induced draft fan and starting a motor of the cold burden proportioning bin;

monitoring cold aggregate temperature and humidity, hot aggregate temperature and flue gas temperature, increasing the rotating speed of a motor of a cold aggregate proportioning bin, increasing a burner accelerator along with the increase of the rotating speed of the motor of the cold aggregate proportioning bin, and increasing an induced draft fan air door along with the increase of the burner accelerator until the preset yield reaches 80%;

monitoring the components of the flue gas, calculating the ratio of CO/CO2, and generating an optimal air-oil ratio curve of 80-100% of a preset yield by adjusting an air door of a combustor;

and the generated optimal air-oil ratio curve is adopted to monitor the temperature of the hot aggregate, the rotating speed of a motor of the proportioning bin and the change of the humidity parameter of the cold aggregate, so that the mixing station can stably produce and automatically regulate and control under low oil consumption.

Further, control cold aggregate humiture, hot aggregate temperature and flue gas temperature, increase cold burden proportioning bins motor speed, the increase of combustor throttle along with cold burden proportioning bins motor speed, the increase of draught fan air door along with the increase of combustor throttle, until reaching the method of presetting 80% of output and including:

after the temperature and the humidity of the cold aggregate are monitored, the rotating speed of a motor of the cold aggregate batching bin is increased;

monitoring whether the temperature of the hot aggregate and the temperature of the flue gas are higher than a maximum set value or not;

if the temperature of the hot aggregate or the temperature of the flue gas is higher than the maximum set value, the rotating speed of a motor of the cold burden proportioning bin is continuously increased;

if the hot aggregate temperature and the flue gas temperature are not higher than the maximum set value, the detected aggregate temperature and the detected aggregate humidity are used as input conditions for calculation, the throttle of the combustor is increased in proportion along with the increase of the rotating speed of the motor of the cold aggregate proportioning bin, and the air door of the induced draft fan is increased in proportion along with the increase of the throttle of the combustor;

when the rotating speed of a motor of the cold burden proportioning bin is increased to 80% of the preset yield, stopping increasing the rotating speed of the motor, and detecting whether the temperature of hot aggregate or the temperature of flue gas reaches a maximum limit value at the moment;

if the temperature of the hot aggregate and the temperature of the flue gas do not reach the maximum limit value, the accelerator of the burner is continuously increased, and the air door of the induced draft fan is increased in proportion;

and if the temperature of the hot aggregate or the temperature of the flue gas reaches the maximum limit value, the accelerator of the burner stops increasing, and the air door of the induced draft fan stops increasing.

Further, the method for monitoring the smoke components and calculating the CO/CO2 ratio and generating the optimal air-oil ratio curve under the condition of 80% -100% of the preset yield by adjusting the air door of the burner comprises the following steps:

reducing the air door of the induced draft fan until the dust removal negative pressure is lower than the minimum limit value;

detecting CO and CO2 components in the smoke and calculating a CO/CO2 ratio;

increasing the air door of the combustor according to a set proportion, and calculating the ratio of CO/CO 2;

if the ratio of CO/CO2 is reduced, the air door of the burner is increased according to a set proportion until the ratio of CO/CO2 is increased, and the optimal air door opening is set to be the air door opening before the ratio of CO/CO2 is increased;

if the ratio of CO/CO2 is increased, the air door of the burner is reduced according to a set proportion, and the ratio of CO/CO2 is calculated;

if the ratio is reduced, the air door of the combustor is continuously reduced according to the set ratio until the ratio of CO/CO2 is increased, the optimal air door opening is set to be the air door opening before the ratio of CO/CO2 is increased, and if the ratio is increased, the optimal air door opening is set to be the original opening;

gradually increasing the actual yield to 100% of the preset yield;

and generating the optimal air-oil ratio curve of the burner at the yield of 80% -100%.

Further, the method further comprises:

when the actual yield is less than 100% of the preset yield, increasing the rotating speed of a motor of the cold burden proportioning bin to increase the yield by 10%, and simultaneously increasing the accelerator of the combustor in proportion;

if the flue gas temperature or the hot aggregate temperature is lower than the limit value, the accelerator of the burner is continuously increased in proportion until the flue gas temperature or the hot aggregate temperature is not lower than the limit value, the components of CO and CO2 in the flue gas are continuously detected, and the ratio of CO/CO2 is calculated.

Further, the set ratio is 3%.

Further, the method for monitoring the change of the hot aggregate temperature, the motor rotating speed of the proportioning bin and the cold aggregate humidity parameter by adopting the generated optimal air-oil ratio curve comprises the following steps:

working by adopting the generated optimal wind-oil ratio curve;

when the temperature of the hot aggregate exceeds the limit value, proportionally increasing or reducing the accelerator of the burner until the temperature of the hot aggregate does not exceed the limit value;

when the rotating speed of a motor of the cold burden proportioning bin is increased or reduced by more than 5%, the throttle of the combustor is increased or reduced in proportion, and the temperature of hot aggregate is not beyond the limit value;

when the humidity of the cold aggregate is increased or reduced by more than 10%, the throttle of the burner is increased or reduced in proportion, and the temperature of the hot aggregate is ensured not to exceed the limit value.

Further, when the temperature of the hot aggregate is lower than a limit value, increasing the accelerator of the combustor; when the hot aggregate temperature is above the limit, the burner throttle is reduced.

The invention provides an asphalt mixing station which is provided with the drying system or the control method.

The invention has the following beneficial effects:

according to the mixing station drying system and the control method provided by the invention, the mixing station drying system is regulated and controlled as a whole, and finally, the automatic sectional control, the accurate enforcement and the real-time matching of the parameters of the whole drying system of the mixing station are realized; the method has the advantages that the optimal air-oil ratio is used for stable production and automatic regulation and control under specific yield, the aggregate temperature, the flue gas temperature and the dedusting effect parameters are qualified, the production efficiency can be improved, the energy consumption level is reduced, and energy conservation and emission reduction are realized.

Drawings

Fig. 1 is a schematic structural diagram of a drying system according to an embodiment of the present invention;

FIG. 2 is a general flow chart of a control method according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating a control procedure at a starting stage in a control method according to an embodiment of the present invention;

fig. 4 is a control flow chart of a matching stage in a control method according to an embodiment of the present invention;

FIG. 5 is a flowchart illustrating a control procedure in a stabilization phase of a control method according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a control system according to an embodiment of the present invention.

Detailed Description

As shown in figures 1 and 6, the invention provides an asphalt mixing station drying system which comprises a cold burden proportioning bin, a feeding buffer bin, a drying roller, a burner, a dust remover, an induced draft fan, a chimney, a corresponding pneumatic pipeline and a corresponding conveying belt.

The feeding surge bin is arranged between the cold burden proportioning bin and the feeding port of the drying roller, the three are connected through the belt conveying mechanism, cold aggregate flows out of the cold burden proportioning bin, passes through the feeding surge bin, and finally flows into the drying roller from the feeding port of the drying roller. Cold aggregate volume of cold burden proportioning bins accessible adjusting motor rotational speed change, the combustor is in drying roller discharge gate one side. The dust remover is positioned between the induced draft fan and the drying roller, the three are connected through a pneumatic pipeline, the pneumatic pipeline between the dust remover and the drying roller is positioned on the upper part of a feed inlet of the drying roller, and an air outlet of the induced draft fan is connected with a chimney.

The feeding buffer bin is internally provided with a cold aggregate temperature sensor and a cold aggregate humidity sensor, the discharge port of the drying roller is provided with a hot aggregate temperature sensor, the dust remover is internally provided with a negative pressure sensor, a pneumatic pipeline between the dust remover and the drying roller is provided with a flue gas temperature sensor, and a chimney is provided with a flue gas component sensor.

As shown in fig. 2-6, the present invention provides a drying system control method, which includes three phases, a first phase being a starting phase, a second phase being a matching phase, and a third phase being a stabilizing phase.

A starting stage: after the output of the preset mixing station is set, the burner is ignited by adopting a default air-oil ratio, the draught fan is started, and the motor of the cold burden proportioning bin is started. After the temperature and the humidity of the cold aggregate are monitored by the temperature and humidity sensors of the cold aggregate in the feeding buffer bin, the rotating speed of the motor of the cold aggregate proportioning bin is gradually increased, and whether the temperature of the hot aggregate and the temperature of the flue gas are higher than the maximum set values or not is monitored. If the temperature of the hot aggregate or the temperature of the flue gas is higher than the maximum set value, the rotating speed of the motor of the cold aggregate proportioning bin is continuously increased, if the temperature of the hot aggregate and the temperature of the flue gas are not higher than the maximum set value, the detected temperature and humidity of the aggregate are used as input conditions for calculation, the throttle of the combustor is increased along with the increase of the rotating speed of the motor of the cold aggregate proportioning bin in proportion, and the throttle of the induced draft fan is increased along with the increase of the throttle of the combustor in proportion. When the rotating speed of the motor of the cold burden proportioning bin is increased to 80% of the preset yield, the rotating speed of the motor stops increasing. Detecting whether the temperature of the hot aggregate or the temperature of the flue gas reaches a maximum limit value at the moment, if the temperature of the hot aggregate and the temperature of the flue gas do not reach the maximum limit value, continuously increasing the accelerator of the burner, and increasing the induced draft fan in proportion; if the temperature of the hot aggregate or the temperature of the flue gas reaches the maximum limit value, the accelerator of the burner stops increasing, the air door of the induced draft fan stops increasing, and the system enters a matching stage.

A matching stage: after entering the matching stage, the yield is 80% of the preset yield, the air door of the induced draft fan is gradually reduced, when the dust removal negative pressure is lower than the minimum limit value, the reduction is stopped, and then the following operations are sequentially executed:

1) detecting CO (ppm) and CO2 (%) components in the flue gas and calculating a CO/CO2 ratio;

2) the burner damper was increased by 3% and the CO/CO2 ratio was calculated. If the ratio is reduced, continuing to increase the air door by 3% until the ratio of CO/CO2 is increased, and setting the optimal air door opening as the air door opening before the ratio of CO/CO2 is increased; if the ratio is increased, executing the next step;

3) the burner damper was reduced by 3% and the CO/CO2 ratio was calculated. If the ratio is reduced, continuing to reduce the air door by 3 percent until the ratio of CO/CO2 is increased, and setting the optimal air door opening as the air door opening before the ratio of CO/CO2 is increased; and if the ratio is increased, setting the optimal opening degree of the air door as the original opening degree.

4) The rotating speed of a motor of the cold burden proportioning bin is increased to increase the yield by 10%, and meanwhile, the accelerator of the combustor is increased in proportion. If the flue gas temperature or the hot aggregate temperature is lower than the limit value in the period, continuing increasing the accelerator of the burner in proportion until the flue gas temperature or the hot aggregate temperature meets the requirement;

5) repeating the steps 1) -4) until the actual yield is 100% of the preset yield;

6) generating the optimal air-oil ratio curve of the burner under the yield of 80% -100%, and entering a stable production stage.

And (3) a stabilization stage: the stage adopts the optimal wind-oil ratio curve generated in the matching stage to work, and when any parameter of the temperature of the hot aggregate, the humidity of the cold aggregate and the rotating speed of the motor of the cold aggregate proportioning bin changes, the accelerator of the combustor is adjusted. The temperature of the hot aggregate is taken as the first priority, the rotating speed of a motor of the proportioning bin is taken as the second priority, and the humidity of the cold aggregate is taken as the third priority. When the temperature of the hot aggregate is lower than the limit value, increasing the accelerator of the burner until the temperature of the hot aggregate meets the requirement; when the temperature of the hot aggregate is higher than the limit value, reducing the accelerator of the burner until the temperature of the hot aggregate meets the requirement; when the rotating speed of a motor of the cold burden proportioning bin is increased or reduced by more than 5%, the throttle of the combustor is increased or reduced in proportion, and the temperature of hot aggregate is not beyond the limit value; when the humidity of the cold aggregate is increased or reduced by more than 10%, the throttle of the burner is increased or reduced in proportion, and the temperature of the hot aggregate is ensured not to exceed the limit value.

The drying system of the asphalt mixing station mainly comprises a cold burden proportioning bin 1, a feeding buffer bin 2, a drying roller 3, a combustor 4, a dust remover 5, an induced draft fan 6, a chimney 7, a discharge port 8 and a pneumatic pipeline 9.

Feeding surge bin 2 is between cold burden proportioning bins 1 and drying roller 3, and the three passes through conveyer to be connected, and cold aggregate flows out from cold burden proportioning bins 1, through feeding surge bin 2, flows into drying roller 3 at last. Cold burden proportioning bins 1 accessible adjusting motor rotational speed changes cold aggregate volume, and combustor 4 is in 8 one sides of the discharge gate of drying drum 3. The dust remover 5 is positioned between the induced draft fan 6 and the drying roller 3, the three are connected through a pneumatic pipeline, the pneumatic pipeline 9 between the dust remover 5 and the drying roller 3 is positioned on the upper part of the feeding side of the drying roller 3, and the air outlet of the induced draft fan 6 is connected with a chimney 7.

The feeding buffer bin 2 is internally provided with a cold aggregate temperature sensor and a cold aggregate humidity sensor, a discharge port 8 of the drying roller 3 is provided with a hot aggregate temperature sensor, the dust remover 5 is internally provided with a negative pressure sensor, a pneumatic pipeline 9 between the dust remover 5 and the drying roller 3 is internally provided with a flue gas temperature sensor, and the chimney 7 is provided with a flue gas component sensor.

The invention provides an asphalt mixing station which is provided with the mixing station drying system or the drying system control method.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.