Method and system for automatically controlling circulation volume of activated carbon

Abstract

The invention discloses a method and system for automatically controlling the circulation amount of activated carbon, and the method specifically comprises the following steps: (1) detecting the yield and concentration of sulfuric acid prepared from sulfur dioxide gas produced by a current desorption tower on line, and analyzing the yield of the sulfur dioxide gas produced by the current desorption tower; (2) analyzing the current working sulfur capacity of the activated carbon in the adsorption tower based on the current sulfur dioxide gas output of the current desorption tower and the current activated carbon circulation volume; and (3) detecting whether the current working sulfur capacity of the activated carbon exceeds the target working sulfur capacity interval, if so, calculating the target frequency of the round roller based on the current sulfuric acid yield and the target working sulfur capacity, and automatically adjusting the rotation frequency of the round roller to the target rotation frequency so as to adjust the circulation volume of the activated carbon. The current working sulfur capacity of the activated carbon is within the target working sulfur capacity range. The circulation volume of the activated carbon is automatically adjusted on line on the basis of detecting the currently prepared sulfuric acid amount of the desorption tower, the circulation volume of the activated carbon changes in a self-adaptive mode along with changes of the currently prepared sulfuric acid amount of the desorption tower, feedback is timely, and the risk that the sulfur content of flue gas does not reach the standard for air exhaust is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of activated carbon desulfurization, and more specifically, to an automatic control method and system for activated carbon circulation amount. Background Art

[0002] The working sulfur capacity of activated carbon is an important factor affecting the operating cost of the activated carbon desulfurization and denitrification flue gas purification process. Since the current activated carbon sulfur capacity detection requires expensive professional testing equipment and scarce technical personnel, companies using activated carbon usually do not have the ability to conduct their own testing.

[0003] Usually, in order to master the working sulfur capacity of activated carbon, the circulating activated carbon can only be sent to a third party for testing, and the third party will feed back the test results to the enterprise. The above-mentioned detection method of the working sulfur capacity of activated carbon has the following problems: Due to the long detection time of the working sulfur capacity of activated carbon, it is difficult for enterprises to timely grasp the changes in the working sulfur capacity of the circulating activated carbon in the activated carbon desulfurization and denitrification system. Due to the influence of the feedback lag of the working sulfur capacity information of the circulating activated carbon, in order to avoid accidents such as hydrogen chloride gas enrichment, ammonium salt crystallization, and substandard emissions caused by the increase in the working sulfur capacity of the circulating activated carbon, enterprises are usually forced to reduce the working sulfur capacity of the circulating activated carbon by increasing the circulation amount of activated carbon. Although this method can temporarily avoid accidents, it will lead to a substantial increase in the production cost of the enterprise, and in severe cases, it is easy to cause the dust particles at the chimney outlet to exceed the standard.

[0004] In addition, there is also the problem of high testing costs when obtaining the working sulfur capacity of activated carbon through third-party testing. Summary of the invention

[0005] The present invention provides an automatic control method for activated carbon circulation amount, aiming to improve at least one of the above problems.

[0006] The present invention is achieved by providing an automatic control method for activated carbon circulation, the method specifically comprising the following steps:

[0007] (1) Online detection of the sulfuric acid output and sulfuric acid concentration produced by the sulfur dioxide gas currently produced by the analytical tower, and analysis of the sulfur dioxide gas output currently produced by the analytical tower

[0008] (2) Based on the sulfur dioxide gas output of the current analytical tower and the current activated carbon circulation volume G RC Analyze the current working sulfur capacity of the activated carbon in the adsorption tower

[0009] (3) Detect the current working sulfur capacity of activated carbon Whether it exceeds the target working sulfur capacity range, if the test result is yes, based on the current sulfuric acid production and the target working sulfur capacity Calculate the target frequency f1 of the round roller, and automatically adjust the rotation frequency of the round roller to the target rotation frequency f1 to adjust the circulation volume of the activated carbon. At this time, the current working sulfur capacity of the activated carbon is within the target working sulfur capacity range.

[0010] Furthermore, the current working sulfur capacity of the activated carbon in the adsorption tower The calculation formula is specifically as follows:

[0011]

[0012] where is the output of sulfur dioxide gas produced by the desorption tower currently, G RC is the current circulation volume of the activated carbon; is the current working sulfur capacity of the activated carbon in the adsorption tower.

[0013] Furthermore, the current circulation volume of the activated carbon G RC The calculation formula is specifically as follows:

[0014]

[0015] where D is the diameter of the round roller; L is the discharging length of the round roller; H is the clearance of the discharging gate of the round roller; ρ is the bulk specific gravity of the activated carbon in the adsorption tower; n1 is the rotational speed of the round roller motor; i is the reduction ratio of the round roller motor; η is the discharging coefficient of the round roller; f0 is the current rotational frequency of the round roller.

[0016] Furthermore, the output of sulfur dioxide gas produced by the current desorption tower The calculation formula is specifically as follows:

[0017]

[0018] where is the output of sulfuric acid produced from the sulfur-rich gas produced by the current desorption tower, and a is the concentration of sulfuric acid produced from the sulfur-rich gas produced by the desorption tower.

[0019] Furthermore, the calculation formula for the target rotational frequency f1 of the round roller is specifically as follows:

[0020]

[0021] where is the target working sulfur capacity of the activated carbon in the adsorption tower, and the target working sulfur capacity of the activated carbon is within the target working sulfur capacity range.

[0022] Furthermore, the target working sulfur capacity range of the activated carbon is 5.0% - 6.0%.

[0023] The present invention is implemented as follows. An automatic control system for the circulating amount of activated carbon, the system comprising:

[0024] An acid concentration meter and a sulfuric acid flow meter provided at the inlet of the sulfuric acid tank, and a control unit communicatively connected to the acid concentration meter and the sulfuric acid flow meter, the control unit being communicatively connected to the round roller;

[0025] The acid concentration meter and the sulfuric acid flow meter are respectively used to detect the concentration and volume flow rate of the sulfuric acid currently produced by the analytical tower and send them to the control unit, and the control unit controls the rotation frequency of the round roller based on the automatic control method for the circulating amount of activated carbon according to any one of claims 1 to 6, thereby adjusting the circulating amount of activated carbon.

[0026] Further, the system further comprises:

[0027] An input unit, connected to the control unit, the input unit being used to input the target working sulfur capacity range of the activated carbon in the adsorption tower.

[0028] Further, the target working sulfur capacity range of the activated carbon is 5.0% - 6.0%.

[0029] The automatic control system for the circulating amount of activated carbon provided by the present invention automatically adjusts the circulating amount of activated carbon online based on the detection of the amount of sulfuric acid currently produced by the analytical tower. The circulating amount of activated carbon changes adaptively with the change of the amount of sulfuric acid currently produced by the analytical tower, with timely feedback, greatly reducing the risk of unqualified flue gas sulfur content for exhaust. Description of the Drawings

[0030] Figure 1 is a flowchart of the automatic control method for the circulating amount of activated carbon provided by an embodiment of the present invention;

[0031] Figure 2 is a structural schematic diagram of the automatic control system for the circulating amount of activated carbon provided by an embodiment of the present invention. Detailed Embodiment

[0032] The following is a more detailed description of the specific embodiments of the present invention with reference to the drawings through the description of the embodiments, so as to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0033] The flue gas with sulfur enters the bin in the adsorption tower, the activated carbon in the bin adsorbs the sulfur in the flue gas, the desulfurized flue gas is discharged from the adsorption tower, the activated carbon adsorbed with sulfur is discharged to the analytical tower through the round roller, the analytical tower releases the sulfur from the activated carbon adsorbed with sulfur to complete the analysis of the activated carbon, the sulfuric acid produced during the analysis process flows into the sulfuric acid tank, and the analyzed activated carbon is circulated to the bin in the adsorption tower through the conveyor.

[0034] Figure 1The flowchart of the automatic control method for the activated carbon circulation amount provided by the embodiment of the present invention is as follows:

[0035] (1) Online detect the sulfuric acid production and sulfuric acid concentration obtained from the sulfur dioxide gas produced by the current analytical tower, and analyze the sulfur dioxide gas production of the current analytical tower

[0036]

[0037] Among them, is the sulfur dioxide gas production in the sulfur-rich gas produced by the current analytical tower, unit: Kg / h; is the sulfuric acid production obtained from the sulfur-rich gas produced by the current analytical tower, unit: Kg / h; a is the sulfuric acid concentration obtained from the sulfur-rich gas produced by the current analytical tower, unit: %.

[0038] In the embodiment of the present invention, the acid concentration meter and the sulfuric acid flow meter are used to detect the concentration a and the volume flow rate of the sulfuric acid currently produced by the analytical tower respectively The sulfuric acid amount currently produced by the analytical tower Among them, is the sulfuric acid density.

[0039] (2) Based on the sulfur dioxide gas production of the current analytical tower and the current circulation amount G of the activated carbon RC analyze the current working sulfur capacity of the activated carbon in the adsorption tower

[0040] In the embodiment of the present invention, the current circulation amount G of the activated carbon RC (i.e., the current activated carbon feeding amount of the adsorption tower) is calculated as follows:

[0041]

[0042] Among them, D is the diameter of the round roller, unit: m; L is the discharging length of the round roller, unit: m; H is the gap of the discharging gate of the round roller, unit: m; ρ is the bulk specific gravity of the activated carbon in the adsorption tower, unit: Kg / m 3 ; n1 is the rotational speed of the round roller motor, unit: r / min; i is the reduction ratio of the round roller motor; η is the discharging coefficient of the round roller; f0 is the current rotation frequency of the round roller, unit: Hz.

[0043] The activated carbon feeding amount G of the adsorption tower RC Summary table of relevant parameters during calculation

[0044]

[0045] In the embodiment of the present invention, the current working sulfur capacity of the activated carbon in the adsorption tower The specific calculation formula is as follows:

[0046]

[0047] Wherein, is the amount of sulfuric acid produced from the sulfur-rich gas produced by the current analytical tower solution, unit: kg / h; G RC is the current feeding amount of activated carbon in the adsorption tower, unit: kg / h, 98 is the molar mass of sulfuric acid, unit Kg / Kmol; 64 is the molar mass of sulfur dioxide in the sulfur-rich gas, unit Kg / Kmol. is the current working sulfur capacity of the activated carbon in the adsorption tower, unit: %, a is the concentration of sulfuric acid currently produced by the analytical tower, and f0 is the current rotation frequency of the round roller.

[0048] (3) Detect the current working sulfur capacity of the activated carbon whether it exceeds the target working sulfur capacity range. If the detection result is yes, based on the current sulfuric acid production and the target sulfur capacity of the activated carbon calculate the target rotation frequency f1 of the round roller. By automatically adjusting the rotation frequency of the round roller to the target rotation frequency f1, the circulation amount of the activated carbon is adjusted to ensure that the current working sulfur capacity of the activated carbon is within the target working sulfur capacity range. If the detection result is no, there is no need to adjust the roller frequency.

[0049] The activated carbon adsorbed with sulfur in the adsorption tower bin is fed to the analytical tower through the round roller, and the activated carbon that has been analyzed in the analytical tower is returned to the bin of the adsorption tower through the conveyor. In order to ensure that the storage amount of the activated carbon in the bin is higher than the set level, the rotation speed of the conveyor is slightly greater than the rotation speed of the round roller, so that the storage amount of the adsorbed carbon in the bin is always higher than the level. When finely adjusting the rotation speed of the round roller, the rotation speed of the conveyor can remain unchanged until the storage amount of the activated carbon reaches the set level, and then the rotation speed of the conveyor will be increased. Of course, when the activated carbon in the bin is close to full, it is also necessary to lower the rotation speed of the conveyor.

[0050] In the embodiment of the present invention, the target working sulfur capacity range of the activated carbon in the adsorption tower is generally set to 5.0% - 6.0%. When the current working sulfur capacity of the activated carbon is within the target working sulfur capacity range, the current rotation frequency f0 of the round roller is also within the target rotation frequency range. The specific calculation formula for the target rotation frequency range of the round roller motor based on the target working sulfur capacity range of the activated carbon in the adsorption tower is as follows:

[0051]

[0052] In the formula (4), s RCWhen it is the upper limit value of the target working sulfur capacity range of the activated carbon in the adsorption tower, then f in formula (4) is the lower limit value of the target rotation frequency range of the round roller, and s in formula (4) RC When it is the lower limit value of the target working sulfur capacity of the activated carbon in the adsorption tower, then f in formula (4) is the lower limit value of the target rotation frequency range of the round roller, and s in formula (4) RC When it is the target working sulfur capacity of the activated carbon, f in formula (4) is the target rotation frequency f1 of the round roller, the target rotation frequency f1 is within the target frequency range, and the target working sulfur capacity is within the target working sulfur capacity range.

[0053] Based on the above formula (3), it can be known that when the amount of sulfuric acid produced from the sulfur-rich gas analyzed in the analysis tower increases, it indicates that the sulfur content in the flue gas entering the adsorption tower is high, and the sulfur adsorbed by the activated carbon in the silo is relatively large. At this time, the working sulfur capacity of the activated carbon in the silo decreases. At this time, by increasing the current rotation frequency of the round roller, the feeding speed of the activated carbon with low working sulfur activity is accelerated, the conveyor replenishes the activated carbon after sulfur analysis, and the sulfur adsorption capacity of the activated carbon in the silo is improved to reduce the emission risk of non-compliant flue gas sulfur content.

[0054] Figure 2 It is a schematic structural diagram of the automatic control system for the activated carbon circulation amount provided by the embodiment of the present invention. For the convenience of description, only the parts related to the embodiment of the present invention are shown. The system includes:

[0055] An acid concentration meter and a sulfuric acid flow meter provided at the inlet of the sulfuric acid tank, and a control unit communicatively connected to the sulfuric acid electromagnetic flow meter. The control unit is communicatively connected to the round roller;

[0056] The acid concentration meter and the sulfuric acid flow meter are respectively used to detect the concentration and volume flow rate V of the sulfuric acid currently produced in the analysis tower H2SO4 and send them to the control unit. The control unit controls the round roller frequency based on the automatic control method for the activated carbon circulation amount, and then realizes the adaptive adjustment of the rotation frequency of the round roller based on the amount of sulfuric acid currently produced in the analysis tower, that is, automatically adjusts the circulation amount of the activated carbon.

[0057] In the embodiment of the present invention, the system further includes: an input unit communicatively connected to the control unit. The target working sulfur capacity of the activated carbon in the adsorption tower is input through the input unit. The target working sulfur capacity range of the activated carbon in the adsorption tower is generally set to 5.0% - 6.0%.

[0058] The automatic control system for the activated carbon circulation amount provided by the present invention automatically adjusts the circulation amount of the activated carbon online based on the detection of the amount of sulfuric acid currently produced in the analysis tower. The circulation amount of the activated carbon changes adaptively with the change of the amount of sulfuric acid currently produced in the analysis tower, greatly reducing the risk of non-compliant exhaust of flue gas sulfur content.

[0059] The present invention has been described by way of example. Obviously, the specific implementation of the present invention is not limited by the above-mentioned methods. As long as various non-substantive improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. An automatic control method for the circulation amount of activated carbon, characterized in that, The method specifically includes the following steps: (1) Online detect the sulfuric acid production and sulfuric acid concentration obtained from the sulfur dioxide gas produced by the current analytical tower, and analyze the sulfur dioxide gas production of the current analytical tower (2) Based on the current sulfur dioxide gas production of the current analytical tower and the current activated carbon circulation volume G RC Analyze the current working sulfur capacity of the activated carbon in the adsorption tower (3) Detect the current working sulfur capacity of the activated carbon Whether it exceeds the target working sulfur capacity range. If the detection result is yes, based on the current sulfuric acid production and the target working sulfur capacity Calculate the target frequency f1 of the circular roller, and automatically adjust the rotation frequency of the circular roller to the target rotation frequency f1 to adjust the circulation volume of the activated carbon. At this time, the current working sulfur capacity of the activated carbon is within the target working sulfur capacity range.

2. The automatic control method for the activated carbon circulation amount as described in claim 1, wherein, Current working sulfur capacity of activated carbon in the adsorption tower The calculation formula is as follows: Among them, is the output of sulfur dioxide gas currently produced by the analytical tower, G RC is the current activated carbon circulation volume; is the current working sulfur capacity of the activated carbon in the adsorption tower.

3. The automatic control method for the activated carbon circulation amount according to claim 2, wherein Current activated carbon circulation volume G RC The calculation formula is as follows: Wherein, D is the diameter of the round roller; L is the discharging length of the round roller; H is the gap of the discharging gate of the round roller; ρ is the bulk specific gravity of the activated carbon in the adsorption tower; n1 is the rotational speed of the round roller motor; i is the reduction ratio of the reducer of the round roller motor; η is the discharging coefficient of the round roller; f0 is the current rotational frequency of the round roller.

4. The automatic control method for the activated carbon circulation amount according to claim 2, characterized in that, The sulfur dioxide gas output produced by the current analytical column The calculation formula is as follows: Among them, is the sulfuric acid production obtained from the sulfur-rich gas produced by the current analysis tower, and a is the sulfuric acid concentration obtained from the sulfur-rich gas produced by the analysis tower.

5. The automatic control method for the activated carbon circulation amount according to claim 1, wherein The specific calculation formula for the target rotational frequency f1 of the round roller is as follows: Among them, is the target working sulfur capacity of activated carbon in the adsorption tower, and the target working sulfur capacity s of the activated carbon RC1 is within the target working sulfur capacity range.

6. The automatic control method for the activated carbon circulation amount according to claim 1, wherein, The target working sulfur capacity range of the activated carbon is 5.0% - 6.0%.

7. An automatic control system for the circulating amount of activated carbon, characterized in that, The system includes: An acid concentration meter and a sulfuric acid flow meter provided at the inlet of the sulfuric acid tank, and a control unit communicatively connected to the acid concentration meter and the sulfuric acid flow meter, and the control unit is communicatively connected to the round roller; The acid concentration meter and the sulfuric acid flow meter are respectively used to detect the concentration and volume flow rate of the sulfuric acid currently produced in the stripping column and send them to the control unit. The control unit controls the rotation frequency of the round roller based on the automatic control method of the activated carbon circulation amount described in any one of claims 1 to 6, and further adjusts the activated carbon circulation amount.

8. The automatic control system for the activated carbon circulation amount according to claim 7, wherein The system further includes: An input unit, connected to the control unit, and the input unit is used to input the target working sulfur capacity range of the activated carbon in the adsorption tower.

9. The activated carbon circulation amount automatic control system according to claim 8, characterized in that, The target working sulfur capacity range of the activated carbon is 5.0% - 6.0%.

Images