TWI780418B - Method for detecting bridge at feed hopper of incinerated system - Google Patents

Abstract

The present invention relates to a method for detecting bridge at a feed hopper of an incinerated system. The incinerated system comprises a furnace unit and an exhaust unit, and a gas of the incinerated system is exhausted to an atmosphere environment from the exhaust unit. In the method, an oxygen concentration of a furnace gas and a flux of a secondary air of the furnace unit are monitored, and a flow rate of the exhaust gas of the incinerated system is monitored, thereby determining whether the bridge is occurred at the feed hopper or not. Therefore, the method of the present invention can efficiently detect the bridge, further preventing a concentration of carbon monoxide of the exhaust gas from substantially increasing.

Description

Detection method of feed inlet bridging in incineration system

The present invention relates to a detection method, and in particular provides a method for detecting whether a bridge occurs at the feed inlet of an incinerator.

General industrial waste can be divided into combustible and non-combustible waste. The combustible waste can be treated by incineration and undergo a series of treatments to form carbon dioxide and hydrogen gas. Combustible industrial waste can be disposed of using an industrial waste incinerator (Industrial Waste Incinerator; IWI).

In the incineration process, through the gasification of high-temperature gas, the solid waste is transformed into a gaseous state, and mixed with oxygen in a high-temperature environment, and further incinerated. In order to improve the exhaust effect of incineration, incineration is carried out under negative pressure. During the feeding process, the waste to be incinerated is first put in from the feeding port and transported to the interior of the incinerator by a screw. When waste gets stuck in the feed port, it will form a "bridge" phenomenon at the feed port of the incinerator. When the bridging phenomenon occurs and the waste in the screw is emptied, the inside of the incinerator will communicate with the outside through the spiral passage of the screw, and a large amount of air will be sucked into the negative pressure environment of the incinerator, thereby greatly reducing the temperature of the incinerator , so that the exhaust gas of the incinerator contains carbon monoxide exceeding the regulatory value (average value of 100 ppm per hour).

Observed from the outside, because the bridging waste is stuck in the feed inlet, and the operator cannot know the conveying condition inside the screw, so it is impossible to know whether the bridging phenomenon has occurred from the outside.

Accordingly, the operator must continuously monitor the parameters of the exhaust gas to avoid situations where the exhaust gas does not comply with regulations. However, when the bridging phenomenon occurs, the operator cannot respond immediately due to the sudden drop in the furnace temperature of the incinerator, and it is impossible to avoid the situation that the exhaust gas does not comply with the regulations.

In view of this, there is an urgent need to provide a detection method for the bridging of the feed inlet of the incineration system, so as to improve the defect that the bridging of the feed inlet of the conventional incineration system cannot be detected.

Therefore, one aspect of the present invention is to provide a detection method for the bridge of the feed inlet of the incineration system. , to judge whether there is a bridging phenomenon at the feed inlet of the incineration unit, so that the operator can eliminate the bridging phenomenon at the feed inlet.

According to one aspect of the present invention, a method for detecting the bridging of the feed inlet of the incineration system is proposed. The incineration system includes an incineration unit and a discharge unit, and the exhaust gas system of the incineration system is discharged into the atmosphere through the discharge unit. In this detection method, a monitoring step is performed first, and then a judgment step is performed. The monitoring step includes monitoring the real-time oxygen concentration of the incineration gas of the incineration unit and the real-time flow rate of the combustion-supporting gas, and monitoring the real-time flow rate of the exhaust gas of the incineration system. The judging step includes judging whether the instant oxygen concentration is greater than the critical oxygen concentration; judging whether the instant flow rate is greater than the critical flow rate; and judging whether the instant flow rate is equal to the set lower limit of the combustion-supporting gas.

When the instant oxygen concentration is greater than the critical oxygen concentration, the instant flow rate is greater than the critical flow rate, and the instant flow rate is equal to the set lower limit, a bridging warning step is performed. When the instant oxygen concentration is not greater than the critical oxygen concentration, the instant flow rate is not greater than the critical flow rate, or the instant flow rate is not equal to the set lower limit value, the aforementioned monitoring step and judging step are performed.

According to an embodiment of the present invention, based on the aforementioned incineration gas being 100 volume percent, the critical oxygen concentration is 10 volume percent.

According to another embodiment of the present invention, based on the maximum flow rate of the exhaust gas from the aforementioned incineration system being 100%, the critical flow rate may be 85% to 95%.

According to yet another embodiment of the present invention, the aforementioned critical velocity is 12.75 m/s to 14.25 m/s.

According to yet another embodiment of the present invention, the flow rate of the aforementioned lower limit value is the minimum flow rate that prevents the pipeline of the combustion-supporting gas from being blocked.

According to yet another embodiment of the present invention, the aforementioned lower limit value is 3500 m ³ /h to 4500 m ³ /h.

According to yet another embodiment of the present invention, when performing the aforementioned bridging and warning step, the detection method may optionally perform a suppression step to reduce the concentration of carbon dioxide in the exhaust gas. The suppressing step includes closing the combustion-supporting gas of the aforementioned incineration unit; reducing the flow rate of the gasification gas of the aforementioned incineration unit; reducing the suction force of the induction fan of the aforementioned incineration system; and increasing the furnace temperature of the aforementioned incineration unit.

According to yet another embodiment of the present invention, the aforementioned operation of increasing the furnace temperature of the incineration unit includes activating all burners in the combustion chamber of the incineration unit.

By applying the detection method of the feed inlet bridging of the incineration system of the present invention, the bridging phenomenon of the incineration unit can be detected in advance, so that the operator can take corresponding elimination procedures, so that the concentration of carbon dioxide in the exhaust gas does not meet the legal control value . Furthermore, the suppression process in the detection method of the present invention can effectively consume the air inhaled due to the bridging phenomenon, and maintain the furnace temperature of the incineration unit, so that the concentration of carbon monoxide can be prevented from exceeding the regulatory value, and the operator has sufficient The time to exclude the bridging of the feed port.

The making and using of embodiments of the invention are discussed in detail below. It should be appreciated, however, that the embodiments provide many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are illustrative only and do not limit the scope of the invention.

Please refer to FIG. 1 , which is a schematic diagram of unit configuration of an incineration system according to some embodiments of the present invention. The incineration system 100 may include an incineration unit 110, a cooling unit 120, a heat exchange unit 130, a reaction unit 140, a dust collection unit 150, and a discharge unit 160, wherein these units are connected by a pipeline 100a, and it can be understood that the pipeline 100a It is used to guide the gas produced by combustion, and finally guide to the discharge unit 160 to be discharged into the atmosphere. Furthermore, for the purpose of clarity, FIG. 1 is only a schematic block diagram, and the actual configuration and connection of each unit are well known to those skilled in the art, so no further details are given here. In some embodiments, the incineration system 100 of the present invention can be an industrial waste incinerator (IWI), or other incineration systems that may have bridging defects.

In the incineration system 100 , waste is put into the feed port of the incineration unit 110 , and after pretreatment (for example: rolling and shredding, etc.), it is put into the combustion chamber of the incineration unit 110 . Then, through the action of high-temperature gasification gas (also known as primary air) blown from the hearth, the waste is transformed from solid to gaseous, and mixed with oxygen in a high-temperature environment to be incinerated . In order to further enhance the effect of incineration, the incineration gas system produced by the initial incineration is further passed into the combustion chamber (ie, the secondary combustion chamber) of the incineration unit 110, and is connected with the combustion gas (also called the secondary air (secondary air) secondary air)) and further secondary combustion. After the secondary combustion, the incineration gas system is sent from the incineration unit 110 to the cooling unit 120 to further reduce the temperature, so as to prevent the high temperature of the incineration gas from damaging the incineration system 100 .

The slightly cooled incineration gas system is further sent to the heat exchange unit 130, and the heat energy of the incineration gas can be used to heat the aforementioned gasification gas and combustion-supporting gas that are not passed into the incineration unit 110, thus reducing the energy cost of the incineration system 100. In some embodiments, the heat exchange unit 130 may be provided with an oxygen detection element to monitor the oxygen concentration of the incineration gas after heat exchange. In other embodiments, according to the configuration of different devices, the aforementioned oxygen detection element can also be arranged in other units.

After the heat exchange, the incineration gas system is further sent to the reaction unit 140 and the dust collection unit 150 in order to remove acid components and dust in the incineration gas by chemical reaction and dust collection bag. In this way, the gas after the reaction and dust collection (ie exhaust gas) can be discharged into the atmosphere through the discharge unit 160 . In some embodiments, the emission unit 160 may include a stationary pollution source continuous monitoring system (Continuous Emission Monitoring System; CEMS) to monitor the composition and flow rate of the exhaust gas.

It can be understood that the incineration system 100 of the present invention continuously incinerates wastes, so the composition, flow rate and flow mentioned in the present invention all change continuously. In order to detect the bridging phenomenon in advance and effectively avoid a large increase in the concentration of carbon dioxide in the exhaust gas, the detection method of the present invention uses real-time measurement to extract various parameters.

Please refer to FIG. 1 and FIG. 2A at the same time, wherein FIG. 2A is a flow chart illustrating a detection method for a feed inlet bridge of an incineration system according to some embodiments of the present invention. The method 200a is a method for detecting whether a bridging phenomenon occurs at the feed inlet of the incineration unit 110 of the incineration system 100 . In the method 200a, the instant oxygen concentration of the incineration gas after the heat exchange treatment, the instant flow rate of the exhaust gas discharged from the discharge unit 160, and the instant flow rate of the combustion-supporting gas in the incineration unit 110 are respectively firstly monitored, such as Operation 210 is shown. The instant oxygen concentration of the incineration gas can be measured by the oxygen detection element in the aforementioned heat exchange unit 130, the instant flow rate of the exhaust gas can be measured by the aforementioned CEMS, and the instant flow rate of the combustion-supporting gas can be measured by the incineration unit 110 in the combustion chamber to measure the flow meter. It is understood that these parameters are measured in no particular order. For example, these parameters can be measured simultaneously or sequentially. In addition, it should be noted that the measurement of the real-time oxygen concentration of the incineration gas is not limited to the aforementioned method. In other embodiments, those with ordinary knowledge in the technical field can use the detection elements arranged in other units. Monitor the instant oxygen concentration of the incineration gas.

Next, proceed to the judgment step 220 . In the judgment step 220, by judging whether the instant oxygen concentration of the incineration gas is greater than the critical oxygen concentration, judging whether the instant flow rate of the exhaust gas is greater than the critical flow rate, and judging whether the instant flow rate of the combustion-supporting gas is equal to the set lower limit of the combustion-supporting gas, etc. (ie operations 221 , 223 and 225 ), it is possible to further detect whether the incineration system 100 has bridging phenomenon. In operation 221 , if the instant oxygen concentration of the incineration gas is greater than the critical oxygen concentration, proceed to operation 223 ; if the instant oxygen concentration of the incineration gas is not greater than (ie less than or equal to) the critical oxygen concentration, proceed to operation 210 . In operation 223, if the instantaneous flow rate of the exhaust gas is greater than the critical flow rate, further proceed to operation 225; if the instantaneous flow rate of the exhaust gas is not greater than (ie less than or equal to) the critical flow rate, continue to perform operation 210. In operation 225, if the immediate flow rate of the combustion-supporting gas is equal to the set lower limit of the combustion-supporting gas, it means that the feed inlet of the incineration unit 110 has bridging phenomenon, and a bridging warning step (as shown in operation 230) must be further carried out to On-site personnel remove waste; if the immediate flow rate of the combustion-supporting gas is not equal to the set lower limit of the combustion-supporting gas, continue the operation 210 . Among them, according to the capacity of the equipment, the operator can adjust the set lower limit of the combustion-supporting gas.

In the aforementioned operation 221 and operation 223, the excessively high oxygen concentration and flow rate represent that the incineration system 100 has additional gas introduced, so the aforementioned operation 225 can further confirm that the additional gas system is caused by the bridging phenomenon, or whether it is It is caused by the protection mechanism of the incineration unit 110 (for example, preventing the pipeline of the combustion-supporting gas (ie, the secondary air pipe) from being blocked by fly ash). As mentioned above, if the immediate flow rate of the combustion-supporting gas is not equal to the set lower limit, it means that the combustion-supporting gas is passing into the incineration unit 110 for protection mechanism, so the additional gas system is the combustion-supporting gas introduced. In other words, there is no bridging phenomenon at the feed inlet of the incineration unit 110 . If the immediate flow rate of the combustion-supporting gas is equal to the set lower limit, it means that the incineration unit 110 has no protection mechanism, so the extra gas system is caused by bridging, and a bridging warning step is required.

In some embodiments, the set lower limit of the flow rate of the combustion-supporting gas may be the minimum operating air volume to prevent the secondary air duct from being blocked by fly ash. In some specific examples, the set lower limit of the flow rate of the combustion-supporting gas may be 3500 m ³ /h to 4500 m ³ /h. In other specific examples, the set lower limit of the flow rate of the combustion-supporting gas is about 3500 m ³ /h to 4000 m ³ /h.

It can be understood that the order of the aforementioned operation 221 , operation 223 and operation 225 is not limited to the content shown in FIG. 2A . In some embodiments, the order of such operations can be changed arbitrarily. In other embodiments, these operations can also be performed simultaneously.

In some specific examples, based on 100 volume percent of the incineration gas, the critical oxygen concentration may be 10 volume percent. Based on the maximum flow rate of the exhaust gas from the incineration system 100 being 100%, the critical flow rate may be 85% to 95%. In these embodiments, the critical velocity of the exhaust gas may range from 12.75 m/s to 14.25 m/s. For example, the critical flow velocity of the exhaust gas may be 14 m/s.

Please refer to FIG. 1 and FIG. 2B , wherein FIG. 2B is a flow chart illustrating a detection method for a feed inlet bridge of an incineration system according to some embodiments of the present invention. The flow of the method 200b is substantially the same as the flow of the aforementioned flow 200a, the difference between the two is that after the judging step 220, if a bridging phenomenon has occurred at the feed inlet of the incineration unit 110, the warning step 230a is performed. In the alerting step 230a, the alerting process and the suppressing process are performed simultaneously, as shown in operation 231 and operation 233 .

In some embodiments, the warning process can notify the monitoring personnel by sending out warning sounds and/or warning lights, so that on-site operators can rule out the bridging of the feed inlet.

Since the bridging phenomenon has occurred at the feed inlet, before the bridging is eliminated, in order to avoid the extra air sucked into the incineration system 100 causing the exhaust gas to not comply with the regulatory value, the suppression process can be carried out. In some embodiments, the suppression process reduces the concentration of carbon dioxide in the exhaust gas. Wherein, the suppression process may include closing the combustion-supporting gas of the incineration unit 110; reducing the flow rate of the gasification gas of the incineration unit 110; reducing the suction force of the induction fan (induce direct fan; I.D. Fan) of the incineration unit 110; The furnace temperature.

In the aforementioned suppression process, due to the bridging phenomenon, extra air is passed into the incineration unit 110, so the gas-supporting system of the incineration unit 110 is closed, and the flow rate of the gasification gas is reduced to reduce the air in the incineration unit 110. The amount of air entering the furnace reduces the temperature drop and reduces the oxygen content in the furnace. In addition, the suction force of the induction fan is reduced to reduce the amount of air sucked in due to bridging. For example, the gasification gas flow rate is reduced from 6000 Nm ³ /min to 5000 Nm ³ /min, and the negative pressure suction force of the induction fan is reduced from 60 mmAQ to 30 mmAQ.

In order to prevent additional air from lowering the furnace temperature of the incineration unit 110, in addition to the aforementioned means of reducing the amount of air entering the furnace, the furnace temperature of the incineration unit 110 can be raised or maintained by activating all burners in the combustion chamber of the incineration unit 110. Furthermore, the additional air drawn in can also be consumed by the burner being turned on to suppress the carbon dioxide concentration in the exhaust gas. For example, the combustion power of the burner in the combustion chamber can be increased to 100% to increase the furnace temperature.

The following examples are used to illustrate the application of the present invention, but they are not intended to limit the present invention. Anyone skilled in this art can make various changes and modifications without departing from the spirit and scope of the present invention.

Example

By means of the simulation program of the incineration system, the embodiment uses the deliberate bridging phenomenon to judge whether the suppression process can avoid a large increase in the concentration of carbon monoxide.

When bridging occurs in the incineration unit of the incineration system, based on the incineration gas of the incineration unit being 100 volume percent, the instant oxygen concentration of the incineration gas is greater than 10 volume percent, the immediate flow velocity of the exhaust gas is greater than 14 m/s, and the combustion-supporting gas The real-time flow rate is equal to the set minimum operating air volume (about 4000 m ³ /h).

After monitoring the changes in the aforementioned parameters, and after 1 to 2 minutes, the concentration of carbon monoxide in the exhaust gas of the incineration system increased significantly. When the carbon monoxide concentration rises, the suppression process is carried out. During the suppression process, the gas-supporting system is closed, the gasification gas flow rate of the incineration unit is reduced from 6000 Nm ³ /min to 5000 Nm ³ /min, and the negative pressure suction force of the induction fan is reduced from 60 mmAQ to 30 mmAQ , and the combustion power of the burners in the combustion chamber is increased to 100%.

When the suppression process is carried out for 4 to 5 minutes, the concentration of carbon dioxide in the exhaust gas is reduced to within the regulatory value.

In addition, after the carbon monoxide concentration is reduced to the regulatory value, the bridging phenomenon is maintained and the suppression process is continued. Within one hour, the immediate concentration of carbon dioxide concentration in the exhaust gas can be reduced to less than 10 ppm, so it can be maintained within the regulatory value.

According to the results of the examples, it can be known that the detection method of the present invention can effectively predict whether the bridging phenomenon occurs at the feed inlet of the incineration unit, so that the operator can perform the bridging elimination process in advance. In addition, by carrying out the above-mentioned suppression process, the increase of carbon dioxide concentration caused by bridging phenomenon can be effectively suppressed, and the exhaust gas of the incineration system is prevented from failing to comply with the regulatory value. Obviously, the suppression process of the present invention can effectively consume the air sucked into the incineration system due to the bridging phenomenon, and maintain the furnace temperature, thereby avoiding the defect that the concentration of carbon dioxide in the exhaust gas increases.

According to the foregoing description, it can be seen that the detection method of the present invention can effectively detect in advance whether the bridging phenomenon occurs at the feed inlet of the incineration unit, so that the operator can immediately eliminate the bridging phenomenon. In addition, through the suppression process in the detection method of the present invention, the air sucked into the incineration unit due to the bridging phenomenon can be effectively consumed, and the temperature of the furnace can be maintained, so that the concentration of carbon dioxide in the exhaust gas can be avoided from increasing significantly. Accordingly, the operator can judge whether there is bridging phenomenon at the feed inlet according to the detection method, and use the suppression process to consume the air sucked in due to bridging, so as to eliminate the bridging phenomenon at the feed inlet.

It can be understood that the detection method of the present invention can continuously monitor the value of each parameter through automatic program control, and immediately judge whether to start the warning process and suppression process of the bridging warning step, so as to effectively avoid the concentration of carbon dioxide caused by the bridging phenomenon Defects that exceed regulatory values.

Although the present invention has been disclosed above in terms of implementation, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field of the present invention can make various modifications and changes without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be defined by the scope of the appended patent application.

100: Incineration system 100a: pipeline 110: Incineration unit 120: cooling unit 130: heat exchange unit 140:Reaction unit 150: dust unit 160: Discharge unit 200a: Method 200b: method 210: Operation 220: Judgment step 221: Operation 223: Operation 225: Operation 230: Operation 230a: Warning step 231: Operation 233: Operation

In order to have a more complete understanding of the embodiments of the present invention and their advantages, please refer to the following descriptions together with the corresponding drawings. It must be emphasized that the various features are not drawn to scale and are for illustration purposes only. The contents of related drawings are explained as follows. FIG. 1 is a schematic diagram showing the unit configuration of an incineration system according to some embodiments of the present invention. FIG. 2A is a flow chart illustrating a method for detecting bridging of a feed inlet of an incineration system according to some embodiments of the present invention. FIG. 2B is a flow chart illustrating a method for detecting bridging of a feed inlet of an incineration system according to some embodiments of the present invention.

Domestic deposit information (please note in order of depositor, date, and number) none Overseas storage information (please note in order of storage country, institution, date, and number) none

200a: Method

210: Operation

220: Judgment step

221: Operation

223: Operation

225: Operation

230: Operation

Claims (7)

A detection method for bridging the inlet of an incineration system, the incineration system includes an incineration unit, a heat exchange unit and a discharge unit, the heat exchange unit is connected between the incineration unit and the discharge unit, and the incineration system An exhaust gas system sequentially passes through the heat exchange unit and the discharge unit, and is discharged into an atmosphere from the discharge unit, wherein the detection method includes: performing a monitoring step, wherein the monitoring step includes: using the heat an oxygen detection element of the exchange unit monitors an instant oxygen concentration of an incineration gas of the incineration unit and monitors an instant flow rate of a combustion-supporting gas by a flow meter of the incineration unit; and monitors by a continuous monitoring system of the discharge unit An immediate flow rate of the exhaust gas of the incineration system; performing a judging step, wherein the judging step includes: judging whether the instant oxygen concentration is greater than a critical oxygen concentration; judging whether the instant flow rate is greater than a critical flow rate; and judging the instant flow rate Whether it is equal to one of the set lower limit values of the combustion-supporting gas, and wherein, when the instant oxygen concentration is greater than the critical oxygen concentration, the instant flow rate is greater than the critical flow rate, and the instant flow rate is equal to the set lower limit value, a bridge warning step is performed and a suppression step to reduce a carbon dioxide concentration of the exhaust gas, wherein the suppression step includes: closing the combustion-supporting gas of the incineration unit; reducing a flow rate of the gasification gas of the incineration unit; reducing the suction of an induction fan of the incineration system; and raising the temperature of a furnace of the incineration unit; When the lower limit is set, the monitoring step and the judging step are performed. The method for detecting the bridging of the feed inlet of the incineration system according to claim 1, wherein the critical oxygen concentration is 10 volume percent based on 100 volume percent of the incineration gas. The method for detecting the bridging of the feed inlet of the incineration system as described in claim 1, wherein a maximum flow rate of the exhaust gas of the incineration system is 100%, and the critical flow rate is 85% to 95%. The detection method of the feed inlet bridge of the incineration system as described in claim 3, wherein the critical flow velocity is 12.75m/s to 14.25m/s. The detection method of the feed inlet bridging of the incineration system as described in Claim 1, wherein the flow rate of the set lower limit is a minimum flow rate that prevents a pipeline of the combustion-supporting gas from being blocked. The detection method for the feed inlet bridging of the incineration system as described in Claim 5, wherein the set lower limit is 3500m ³ /h to 4500m ³ /h. The method for detecting the bridging of the feed inlet of the incineration system as described in Claim 1, wherein the operation of increasing the furnace temperature of the incineration unit includes starting all burners in a combustion chamber of the incineration unit.

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