An intelligent control system and method for backwashing of the quench zone and cross hanger of a gasifier

Abstract

Intelligent control system and method for backwashing of the quench zone and cross hanger of the gasifier of the present invention: The backwashing control of the quench zone and the cross hanger is set in one program, and the action time and interval time of the backwashing valve are controlled by the same program, which can well control the action of the backwashing valves in the quench section and the cross hanger. The action intervals of the backwashing valves are in order, effectively solving the problem of difficult control of the intervals of the backwashing of the quench zone and the cross hanger, and can greatly reduce the influence of the system backwashing on the pressure of the gasifier and the feed water volume of the steam drum. Also, each time the backwashing valve acts, intelligent control measures are added to prevent the high-temperature hot gas in the gasifier from returning and burning out the internal parts of the gasifier and prevent fly ash from entering the annular space of the gasifier (automatically opening the nitrogen supply valve before the backwashing valve acts and automatically closing it after the backwashing is completed), effectively ensuring that the pressure in the annular space is always higher than the pressure in the furnace of the gasifier when the backwashing valve of the gasifier backwashes, preventing high-temperature gas from returning and burning out the quench pan and preventing ash accumulation in the annular space, and realizing intelligent control.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent control, and in particular to an intelligent control system and method for backwashing of the quench zone and cross hanger of a gasifier. Background Art

[0002] In the Shell design, the quench zone and cross hanger of the Shell gasifier are both backwashed with ultra-high pressure nitrogen / carbon dioxide at 7.8 MPa. The action and timing of the backwash valve in the quench zone are controlled by the quench zone backwash program 13KS5, and the action and timing of the backwash valve of the cross hanger are controlled by the cross hanger backwash program 13KS4. The two types of backwashing are controlled separately by two sequence controls. The interval time between the two types of backwashing is sometimes long and sometimes short, which is very difficult to control, and the influence on the gasifier is uncontrollable. When the quench zone backwash program and the cross hanger backwash program of the gasifier are running, the influence on the gasifier pressure and the feed water volume of the steam drum is very likely to be superimposed, causing the gasifier pressure and the feed water volume of the steam drum to fluctuate repeatedly. Moreover, due to a large amount of gas being instantaneously blown into the gasifier, the pressure inside the gasifier is instantaneously higher than the pressure in the annular space of the gasifier, resulting in the backflow of the high-temperature hot gas at 1450 °C inside the gasifier, burning out the internal components of the gasifier such as the quench disc and the breathing holes in the annular space. A large amount of fly ash inside the gasifier will also enter the annular space of the gasifier along with the backflow gas, causing serious ash accumulation in the annular space.

[0003] Therefore, developing a more intelligent backwash program for the quench zone and cross hanger of the gasifier has far-reaching significance for ensuring the safe and stable operation of the gasifier and preventing ash accumulation in the annular space of the gasifier. Summary of the Invention

[0004] The present invention aims at the problems and deficiencies existing in the prior art, and provides a novel intelligent control system and method for backwashing of the quench zone and cross hanger of a gasifier.

[0005] The present invention solves the above technical problems through the following technical solutions:

[0006] The present invention provides an intelligent control system for the counter-blowing of the quench zone and the cross hanger of a gasifier, which is characterized in that it includes a controller. The controller is used to control the nitrogen supply of the nitrogen supply valve in the gasification annular space and the counter-blowing process of the counter-blowing valve in the quench zone: when the major interlock of the gasifier is normal and the pressure of the gasifier > 3.6 MPa, control the opening degree of the nitrogen supply valve in the gasification annular space to increase from 5% to 85% to supply nitrogen into the annular space. After the nitrogen supply valve in the gasification annular space is opened for the first set time, open the counter-blowing valve in the quench zone for counter-blowing. After the counter-blowing valve in the quench zone is opened for counter-blowing for the second set time, close the counter-blowing valve in the quench zone. After the second set time + 1 second, control the opening degree of the nitrogen supply valve in the gasification annular space to close from 85% to 5%. After the nitrogen supply valve in the gasification annular space is opened for the third set time, determine whether the opening degree of the nitrogen supply valve in the gasification annular space has closed from 85% to 5%. When the result is no, control the opening degree of the nitrogen supply valve in the gasification annular space to close from 85% to 5%. The second set time < the first set time < the third set time;

[0007] The controller is used to control the nitrogen supply of the nitrogen supply valve in the gasification annular space and the counter-blowing process of the cross hanger counter-blowing valve: after the counter-blowing valve in the quench zone is closed for the fourth set time, when the major interlock of the gasifier is normal and the pressure of the gasifier > 3.6 MPa, control the opening degree of the nitrogen supply valve in the gasification annular space to increase from 5% to 85% to supply nitrogen into the annular space. After the nitrogen supply valve in the gasification annular space is opened for the first set time, open the cross hanger counter-blowing valve for counter-blowing. After the cross hanger counter-blowing valve is opened for counter-blowing for the second set time, close the cross hanger counter-blowing valve. After the second set time + 1 second, control the nitrogen supply valve in the gasification annular space to close from 85% to 5%. After the nitrogen supply valve in the gasification annular space is opened for the third set time, determine whether the opening degree of the nitrogen supply valve in the gasification annular space has closed from 85% to 5%. When the result is no, control the nitrogen supply valve in the gasification annular space to close from 85% to 5%. The third set time < the fourth set time;

[0008] After the cross hanger counter-blowing valve is closed for the fourth set time, the controller is used to sequentially and cyclically execute the process of controlling the nitrogen supply of the nitrogen supply valve in the gasification annular space and the counter-blowing process of the counter-blowing valve in the quench zone, and the process of controlling the nitrogen supply of the nitrogen supply valve in the gasification annular space and the counter-blowing process of the cross hanger counter-blowing valve.

[0009] An intelligent control method for the counter-blowing of the quench zone and the cross hanger of a gasifier, which is characterized in that it includes the following steps:

[0010] Step 1. Control the nitrogen supply of the gasification annular space nitrogen supply valve and the backwashing process of the quench zone backwashing valve: When the major interlock of the gasifier is normal and the gasifier pressure > 3.6 MPa, control the opening of the gasification annular space nitrogen supply valve to increase from 5% to 85% to supply nitrogen to the annular space. After the gasification annular space nitrogen supply valve is opened for the first set time, open the quench zone backwashing valve for backwashing. After the quench zone backwashing valve is opened for backwashing for the second set time, close the quench zone backwashing valve. After the second set time + 1 second, control the opening of the gasification annular space nitrogen supply valve to close from 85% to 5%. After the gasification annular space nitrogen supply valve is opened for the third set time, determine whether the opening of the gasification annular space nitrogen supply valve has closed from 85% to 5%. If not, control the opening of the gasification annular space nitrogen supply valve to close from 85% to 5%. The second set time < the first set time < the third set time;

[0011] Step 2. Control the nitrogen supply of the gasification annular space nitrogen supply valve and the backwashing process of the cross hanger backwashing valve: After the quench zone backwashing valve is closed for the fourth set time, when the major interlock of the gasifier is normal and the gasifier pressure > 3.6 MPa, control the opening of the gasification annular space nitrogen supply valve to increase from 5% to 85% to supply nitrogen to the annular space. After the gasification annular space nitrogen supply valve is opened for the first set time, open the cross hanger backwashing valve for backwashing. After the cross hanger backwashing valve is opened for backwashing for the second set time, close the cross hanger backwashing valve. After the second set time + 1 second, control the gasification annular space nitrogen supply valve to close from 85% to 5%. After the gasification annular space nitrogen supply valve is opened for the third set time, determine whether the opening of the gasification annular space nitrogen supply valve has closed from 85% to 5%. If not, control the gasification annular space nitrogen supply valve to close from 85% to 5%. The third set time < the fourth set time;

[0012] Step 3. After the cross hanger backwashing valve is closed for the fourth set time, sequentially and cyclically execute Step 1 and Step 2.

[0013] The positive and progressive effects of the present invention are as follows:

[0014] The present invention has the characteristics of high automation, convenient operation, good control effect, etc. Since the intelligent backwashing system was put into use, the problems of ablation of the gasifier quench pan and ash accumulation in the annular space have been effectively solved, and the superposition effect of the gasifier pressure and the feed water volume of the steam drum has been alleviated, laying a solid foundation for the long-term operation of the coal gasification device. Description of the Drawings

[0015] Figure 1 It is the intelligent control diagram of the quench zone and cross hanger backwashing of the gasifier in the preferred embodiment of the present invention. Detailed Embodiment

[0016] To make the objectives, 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 accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0017] As Figure 1 shown, this embodiment provides an intelligent control system for the counter-blowing of the quench zone and cross hanger of a gasifier, which includes a controller. The controller is used to control the nitrogen replenishment of the gasification annular space nitrogen replenishment valve and the counter-blowing process of the quench zone counter-blowing valve: when the major interlock of the gasifier is normal and the gasifier pressure 13PI0068 > 3.6 MPa, slowly control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to increase from 5% to 85% to replenish nitrogen into the annular space. After the gasification annular space nitrogen replenishment valve is opened for 80 s, open the quench zone counter-blowing valve 13XV0103 for counter-blowing. After the quench zone counter-blowing valve 13XV0103 is opened for counter-blowing for 10 s, close the quench zone counter-blowing valve 13XV0103. After the quench zone counter-blowing valve is opened for counter-blowing for 11 s, control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%. After the gasification annular space nitrogen replenishment valve is opened for 102 s, determine whether the opening of the gasification annular space nitrogen replenishment valve has closed from 85% to 5%. If not, control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%.

[0018] The controller is used to control the nitrogen replenishment of the gasification annular space nitrogen replenishment valve and the counter-blowing process of the cross hanger counter-blowing valve: after the quench zone counter-blowing valve 13XV0103 is closed for 360 s, when the major interlock of the gasifier is normal and the gasifier pressure 13PI0068 > 3.6 MPa, slowly control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to increase from 5% to 85% to replenish nitrogen into the annular space. After the gasification annular space nitrogen replenishment valve is opened for 80 s, open the cross hanger counter-blowing valve 13XV0034 for counter-blowing. After the cross hanger counter-blowing valve 13XV0034 is opened for counter-blowing for 10 s, close the cross hanger counter-blowing valve 13XV0034. After the cross hanger counter-blowing valve is opened for counter-blowing for 11 s, control the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%. After the gasification annular space nitrogen replenishment valve is opened for 102 s, determine whether the opening of the gasification annular space nitrogen replenishment valve has closed from 85% to 5%. If not, control the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%.

[0019] The controller is used to, after the cross hanger backflush valve 13XV0034 is closed for 360 s, sequentially and cyclically execute the process of controlling the nitrogen replenishment of the gasification annular space nitrogen replenishment valve, the backflush process of the quench zone backflush valve, and the process of controlling the nitrogen replenishment of the gasification annular space nitrogen replenishment valve and the backflush process of the cross hanger backflush valve.

[0020] This embodiment also provides an intelligent control method for the quench zone and cross hanger backflush of a gasifier, which includes the following steps:

[0021] Step 1, control the nitrogen replenishment of the gasification annular space nitrogen replenishment valve and the backflush process of the quench zone backflush valve: When the major interlock of the gasifier is normal and the gasifier pressure 13PI0068 > 3.6 MPa, slowly control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to increase from 5% to 85% to replenish nitrogen into the annular space. After the gasification annular space nitrogen replenishment valve is opened for 80 s, open the quench zone backflush valve 13XV0103 for backflush. After the quench zone backflush valve 13XV0103 is opened for backflush for 10 s, close the quench zone backflush valve 13XV0103. After the quench zone backflush valve is opened for backflush for 11 s, control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%. After the gasification annular space nitrogen replenishment valve is opened for 102 s, determine whether the opening of the gasification annular space nitrogen replenishment valve has closed from 85% to 5%. If not, control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%.

[0022] Step 2, control the nitrogen replenishment of the gasification annular space nitrogen replenishment valve and the backflush process of the cross hanger backflush valve: After the quench zone backflush valve 13XV0103 is closed for 360 s, when the major interlock of the gasifier is normal and the gasifier pressure 13PI0068 > 3.6 MPa, slowly control the opening of the gasification annular space nitrogen replenishment valve 13HV0008 to increase from 5% to 85% to replenish nitrogen into the annular space. After the gasification annular space nitrogen replenishment valve is opened for 80 s, open the cross hanger backflush valve 13XV0034 for backflush. After the cross hanger backflush valve 13XV0034 is opened for backflush for 10 s, close the cross hanger backflush valve 13XV0034. After the cross hanger backflush valve is opened for backflush for 11 s, control the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%. After the gasification annular space nitrogen replenishment valve is opened for 102 s, determine whether the opening of the gasification annular space nitrogen replenishment valve has closed from 85% to 5%. If not, control the gasification annular space nitrogen replenishment valve 13HV0008 to close from 85% to 5%.

[0023] Step 3, after the cross hanger backflush valve 13XV0034 is closed for 360 s, sequentially and cyclically execute Step 1 and Step 2.

[0024] The control system sets the counter-blowing of the quench zone and the counter-blowing of the cross hanger in one program. The action time and interval time of the counter-blowing valve are controlled by the same program, which can well control the action of the counter-blowing valves in the quench section and the cross hanger. The action intervals of the counter-blowing valves are in order, which can effectively solve the problem that it is difficult to control the counter-blowing intervals of the quench zone and the cross hanger, and can greatly reduce the impact of the system counter-blowing on the gasifier pressure and the feed water volume of the steam drum.

[0025] Moreover, when the counter-blowing valve acts each time, the control system also adds intelligent control measures to prevent the high-temperature hot gas in the gasifier from flowing back and burning out the internal components of the gasifier and prevent fly ash from entering the annular space of the gasifier (automatically opening the nitrogen supplement valve 13HV0008 of the gasification annular space before the counter-blowing valve acts and automatically closing it after the counter-blowing is completed), which can effectively ensure that the pressure in the annular space is always higher than the pressure in the gasifier furnace during the counter-blowing of the gasifier counter-blowing valve, prevent high-temperature gas from flowing back and burning out the quench disk and ash accumulation in the annular space, and achieve intelligent control.

[0026] The intelligent control of the counter-blowing of the quench zone and the cross hanger of the gasifier is as follows: the counter-blowing of the quench zone and the cross hanger are set to be completed in the same sequence control program. The interval between the two types of counter-blowing is adjusted to 12 minutes. When 80 s before the counter-blowing valves 13XV0X03 and 13XV0034 are opened, the opening of the nitrogen supplement valve 13HV0008 of the gasification annular space is increased from 5% to 85% to inflate the annular space. After 11 s or 102 s when the counter-blowing valves are opened, the nitrogen supplement valve 13HV0008 of the gasification annular space is closed from 85% to 5% to maintain that the pressure in the gasifier annular space is always higher than the pressure in the gasifier furnace during the counter-blowing of the counter-blowing valve, prevent high-temperature gas from flowing back and burning out the quench disk and ash accumulation in the annular space, and achieve the purpose of intelligent control.

[0027] Although the specific implementation manners of the present invention are described above, those skilled in the art should understand that these are only examples. The protection scope of the present invention is defined by the appended claims. Without departing from the principles and essence of the present invention, those skilled in the art can make various changes or modifications to these implementation manners, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. An intelligent control system for backwashing the quench zone and cross hanger of a gasifier, characterized in that, It includes a controller which is used to control the nitrogen supply of the nitrogen supply valve for the gasification annular space and the backwashing process of the quench zone backwashing valve: when the major interlock of the gasifier is normal and the gasifier pressure > 3.6 MPa, control the opening degree of the nitrogen supply valve for the gasification annular space to increase from 5% to 85% to supply nitrogen into the annular space. After the nitrogen supply valve for the gasification annular space is opened for the first set time, open the quench zone backwashing valve for backwashing. After the quench zone backwashing valve is opened for backwashing for the second set time, close the quench zone backwashing valve. After the second set time + 1 second, control the opening degree of the nitrogen supply valve for the gasification annular space to close from 85% to 5%. After the nitrogen supply valve for the gasification annular space is opened for the third set time, determine whether the opening degree of the nitrogen supply valve for the gasification annular space has closed from 85% to 5%. If not, control the opening degree of the nitrogen supply valve for the gasification annular space to close from 85% to 5%. The second set time < the first set time < the third set time; The controller is used to control the nitrogen supply of the nitrogen supply valve for the gasification annular space and the backwashing process of the cross hanger backwashing valve: after the quench zone backwashing valve is closed for the fourth set time, when the major interlock of the gasifier is normal and the gasifier pressure > 3.6 MPa, control the opening degree of the nitrogen supply valve for the gasification annular space to increase from 5% to 85% to supply nitrogen into the annular space. After the nitrogen supply valve for the gasification annular space is opened for the first set time, open the cross hanger backwashing valve for backwashing. After the cross hanger backwashing valve is opened for backwashing for the second set time, close the cross hanger backwashing valve. After the second set time + 1 second, control the nitrogen supply valve for the gasification annular space to close from 85% to 5%. After the nitrogen supply valve for the gasification annular space is opened for the third set time, determine whether the opening degree of the nitrogen supply valve for the gasification annular space has closed from 85% to 5%. If not, control the nitrogen supply valve for the gasification annular space to close from 85% to 5%. The third set time < the fourth set time; After the cross hanger backwashing valve is closed for the fourth set time, the controller is used to sequentially and cyclically execute the process of controlling the nitrogen supply of the nitrogen supply valve for the gasification annular space and the backwashing process of the quench zone backwashing valve, and the process of controlling the nitrogen supply of the nitrogen supply valve for the gasification annular space and the backwashing process of the cross hanger backwashing valve.

2. An intelligent control method for backwashing in the quench zone and cross hanger of a gasifier, characterized in that, It includes the following steps: Step 1, control the nitrogen supply of the nitrogen supply valve for the gasification annular space and the backwashing process of the quench zone backwashing valve: when the major interlock of the gasifier is normal and the gasifier pressure > 3.6 MPa, control the opening degree of the nitrogen supply valve for the gasification annular space to increase from 5% to 85% to supply nitrogen into the annular space. After the nitrogen supply valve for the gasification annular space is opened for the first set time, open the quench zone backwashing valve for backwashing. After the quench zone backwashing valve is opened for backwashing for the second set time, close the quench zone backwashing valve. After the second set time + 1 second, control the opening degree of the nitrogen supply valve for the gasification annular space to close from 85% to 5%. After the nitrogen supply valve for the gasification annular space is opened for the third set time, determine whether the opening degree of the nitrogen supply valve for the gasification annular space has closed from 85% to 5%. If not, control the opening degree of the nitrogen supply valve for the gasification annular space to close from 85% to 5%. The second set time < the first set time < the third set time; Step 2. Control the nitrogen supplementation process of the gasification annular space nitrogen supplementation valve and the backwashing process of the cross hanger backwashing valve: After the backwashing valve in the quench zone is closed for the fourth set time, when the large interlock of the gasifier is normal and the pressure of the gasifier > 3.6 MPa, control the opening of the gasification annular space nitrogen supplementation valve to increase from 5% to 85% to supplement nitrogen into the annular space. After the gasification annular space nitrogen supplementation valve is opened for the first set time, open the cross hanger backwashing valve for backwashing. After the cross hanger backwashing valve is opened for backwashing for the second set time, close the cross hanger backwashing valve. After the second set time + 1 second, control the gasification annular space nitrogen supplementation valve to close from 85% to 5%. After the gasification annular space nitrogen supplementation valve is opened for the third set time, determine whether the opening of the gasification annular space nitrogen supplementation valve closes from 85% to 5%. If not, control the gasification annular space nitrogen supplementation valve to close from 85% to 5%. The third set time < the fourth set time; Step 3. After the cross hanger backwashing valve is closed for the fourth set time, sequentially and cyclically execute Step 1 and Step 2.

Images