Gasification furnace and oxygen flow control method of one-section coal burner of gasification furnace

Abstract

The invention provides a gasification furnace, an oxygen flow control method of a first-section coal burner of the gasification furnace and the gasification furnace. The gasification furnace comprises a furnace body, a first-section coal burner and a second-section coal burner, the first-section coal burner is communicated with the side wall of the furnace body; the second-section coal burner is communicated with the side wall of the furnace body and is positioned above the first-section coal burner; the gas outlet is communicated with the top of the furnace body; and the coal cinder outlet is communicated with the bottom of the furnace body. According to the technical scheme provided by the invention, the problem of energy waste of the gasification furnace caused by relatively low conversion rate of the dry pulverized coal synthetic gas in related technologies is effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of gasifiers, and in particular to a gasifier and an oxygen flow control method for a first-stage coal burner of the gasifier. Background Art

[0002] The efficient and clean utilization of coal is the current and future development direction, and coal gasification technology is the basic technology applicable to this development direction. Dry coal powder is pressurized and gasified in the gasifier to produce synthetic coal gas.

[0003] The gasifier comprises a furnace body and a coal burner arranged on the furnace body, and oxygen and dry coal powder enter into the furnace body through the coal burner.

[0004] In the related art, multiple coal burners are arranged at intervals along the circumference of the furnace body, and the multiple coal burners are located in the same horizontal plane, which makes it easy for dry coal powder in the furnace body to gather together, resulting in a low conversion rate of dry coal powder to synthesize coal gas, resulting in energy waste of the gasifier. Summary of the invention

[0005] The main purpose of the present invention is to provide a gasifier and a method for controlling the oxygen flow rate of a first-stage coal burner of the gasifier, so as to solve the problem in the related art that the conversion rate of dry coal powder into synthetic coal gas is low, resulting in energy waste in the gasifier.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a gasification furnace is provided, comprising: a furnace body; a first-stage coal burner connected to the side wall of the furnace body; a second-stage coal burner connected to the side wall of the furnace body and located above the first-stage coal burner; a gas exhaust port connected to the top of the furnace body; and a slag exhaust port connected to the bottom of the furnace body.

[0007] Furthermore, there are multiple first-stage coal burners, which are evenly spaced along the circumference of the furnace body; and / or, the first-stage coal burner includes a first pipe section extending into the furnace body and a second pipe section passing through the furnace body, and the diameter of the first pipe section gradually decreases from the inside to the outside.

[0008] Furthermore, there are two two-stage coal burners, which are equally spaced along the circumference of the furnace body; and / or, the two-stage coal burner includes a third pipe section extending into the furnace body and a fourth pipe section passing through the furnace body, and the diameter of the third pipe section gradually decreases from the inside to the outside.

[0009] According to another aspect of the present invention, a method for controlling the oxygen flow rate of a first-stage coal burner of a gasifier is provided, which is used to control the oxygen flow rate of a first-stage coal burner of the gasifier. The method for controlling the oxygen flow rate of a first-stage coal burner of the gasifier comprises the following steps:

[0010] According to the load demand of the syngas product produced by the gasifier, the first pseudo load demand of the total oxygen of the gasifier is set;

[0011] According to the commissioning of the second-stage coal burner, set the second pseudo-load demand of total oxygen in the gasifier;

[0012] Determine the total oxygen load demand X of the gasifier according to the first pseudo-load demand of the total oxygen of the gasifier and the second pseudo-load demand of the total oxygen of the gasifier;

[0013] Control the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and control the total oxygen load demand X of the gasifier between a first upper limit value and a first lower limit value to obtain a corrected total oxygen load demand of the gasifier;

[0014] According to the number of primary coal burners and the corrected total oxygen load demand of the gasifier, the oxygen load demand Y of a single primary coal burner is calculated;

[0015] The oxygen load demand Y of the single first-stage coal burner is controlled between the second upper limit value and the second lower limit value to obtain the corrected oxygen load demand of the single first-stage coal burner;

[0016] The corrected oxygen load demand of a single one-stage coal burner is input into the controller, and the corrected oxygen load of the single one-stage coal burner is compared with the actual measured value of the oxygen flow of the single one-stage coal burner to adjust the oxygen flow of the one-stage coal burner.

[0017] Furthermore, according to the commissioning of the second-stage coal burner, the step of setting the second simulated total oxygen load demand of the gasifier includes:

[0018] When all the second-stage coal burners are not put into use, the second pseudo-load demand of total oxygen in the gasifier is set below 58% of the rated oxygen flow rate of the gasifier;

[0019] When a second-stage coal burner is put into use, the second pseudo-load demand of the total oxygen of the gasifier is set below 65% of the rated oxygen flow of the gasifier;

[0020] When two second-stage coal burners are put into use, the total oxygen second pseudo load demand of the gasifier is set below 100% of the rated oxygen flow of the gasifier.

[0021] Further, the step of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and controlling the total oxygen load demand X of the gasifier to be between a first upper limit value and a first lower limit value, and obtaining a corrected total oxygen load demand of the gasifier includes:

[0022] The set value is determined based on 3% of the maximum mass flow rate of oxygen in the gasifier.

[0023] Further, the step of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and controlling the total oxygen load demand X of the gasifier to be between a first upper limit value and a first lower limit value, and obtaining a corrected total oxygen load demand of the gasifier includes:

[0024] When the gasifier pressure is less than 1 MPa, the first upper limit is determined to be 4.76 kg / s;

[0025] When 3MPa≥gasifier pressure≥1MPa, the first upper limit value is determined according to the following formula: first upper limit value=gasifier pressure×6.48-1.72;

[0026] When the gasifier pressure is greater than 3 MPa, the first upper limit is determined to be 17.72 kg / s;

[0027] When the gasifier pressure is less than 1 MPa, the first lower limit is determined to be 2.2 kg / s;

[0028] When 3MPa≥gasifier pressure≥1MPa, the first lower limit is determined according to the following formula: first lower limit=gasifier pressure×2.1+0.1;

[0029] When the gasifier pressure is greater than 3 MPa, the first lower limit is determined to be 6.4 kg / s.

[0030] Further, the step of controlling the oxygen load demand Y of a single first-stage coal burner between a second upper limit and a second lower limit to obtain a corrected oxygen load demand of a single first-stage coal burner includes:

[0031] When the gasifier pressure is less than 1 MPa, the second upper limit is determined to be 1.38 kg / s;

[0032] When 3MPa≥gasifier pressure≥1MPa, the second upper limit value is determined according to the following formula: second upper limit value=gasifier pressure×1.425-0.045;

[0033] When the gasifier pressure is greater than 3 MPa, the second upper limit is determined to be 4.23 kg / s;

[0034] When the gasifier pressure is less than 1 MPa, the second lower limit is determined to be 1.25 kg / s;

[0035] When 3MPa≥gasifier pressure≥1MPa, the second lower limit is determined according to the following formula: second lower limit=gasifier pressure×0.18+1.07;

[0036] When the gasifier pressure is greater than 3 MPa, the second lower limit is determined to be 1.61 kg / s.

[0037] Further, the step of controlling the oxygen load demand Y of the single first-stage coal burner between the second upper limit and the second lower limit to obtain the corrected oxygen load demand of the single first-stage coal burner further includes:

[0038] When the oxygen load demand Y of a single first-stage coal burner is less than the second lower limit value, the corrected oxygen load demand of the single first-stage coal burner is determined as the second lower limit value;

[0039] When the oxygen load demand Y of a single first-stage coal burner is greater than the second upper limit value, the corrected oxygen load demand of the single first-stage coal burner is determined as the second upper limit value;

[0040] When the oxygen load demand Y of a single one-stage coal burner is between the second lower limit value and the second upper limit value, the corrected oxygen load demand of the single one-stage coal burner is determined as the oxygen load demand Y of the single one-stage coal burner.

[0041] Further, according to the first pseudo total oxygen load demand of the gasifier and the second pseudo total oxygen load demand of the gasifier, the step of determining the total oxygen load demand X of the gasifier includes:

[0042] The minimum value of the first pseudo-load demand of total oxygen in the gasifier and the second pseudo-load demand of total oxygen in the gasifier is taken as the total oxygen load demand X of the gasifier.

[0043] According to the technical solution of the present invention, the gasifier includes: a furnace body, a first-stage coal burner, a second-stage coal burner, a gas outlet and a slag outlet. The first-stage coal burner is connected to the side wall of the furnace body. The second-stage coal burner is connected to the side wall of the furnace body and is located above the first-stage coal burner. The gas outlet is connected to the top of the furnace body. The slag outlet is connected to the bottom of the furnace body. In this way, through the arrangement of the second-stage coal burner, dry coal powder can be introduced into the furnace body above the first-stage coal burner, so that the dry coal powder can be pressurized and gasified into synthetic coal gas above the first-stage coal burner. The distribution of dry coal powder in the gasifier in the vertical direction is more uniform, the utilization of the energy of the furnace body is improved, and the conversion rate of the gasifier is improved. In addition, the first-stage coal burner can introduce oxygen and dry coal powder into the furnace body, pressurize the dry coal powder in the furnace body, and the synthetic coal gas can be discharged from the gas outlet, and the slag generated after the dry coal powder is pressurized can be discharged from the slag outlet. Therefore, the technical solution of the present application effectively solves the problem in the related art that the conversion rate of dry coal powder into synthetic coal gas is low, resulting in energy waste in the gasifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0045] Figure 1 A schematic structural diagram of an embodiment of a gasifier according to the present invention is shown;

[0046] Figure 2 Shows Figure 1 A schematic cross-sectional view of a section of a coal burner of a gasifier when viewed from above;

[0047] Figure 3 Shows Figure 1 A schematic cross-sectional view of the second-stage coal burner of the gasifier when viewed from above;

[0048] Figure 4 A flow chart showing a method for controlling the oxygen flow rate of a coal burner of a gasifier according to the present invention is shown;

[0049] Figure 5 Shows Figure 4 A control logic diagram of an oxygen flow control method for a coal burner of a gasifier.

[0050] The above drawings include the following reference numerals:

[0051] 10. Furnace body;

[0052] 20. A first section of coal burner; 21. A first pipe section; 22. A second pipe section; 23. A first regulating valve; 24. A second regulating valve;

[0053] 30. Second stage coal burner; 31. Third pipe section; 32. Fourth pipe section; 33. Third regulating valve;

[0054] 40. Gas exhaust port;

[0055] 50. Coal slag discharge outlet;

[0056] 60. Slag collection tank. DETAILED DESCRIPTION

[0057] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0059] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0060] In this embodiment, if Figures 1 to 3 As shown, the gasifier includes: a furnace body 10, a first-stage coal burner 20, a second-stage coal burner 30, a gas outlet 40, and a slag outlet 50. The first-stage coal burner 20 is connected to the side wall of the furnace body 10. The second-stage coal burner 30 is connected to the side wall of the furnace body 10 and is located above the first-stage coal burner 20. The gas outlet 40 is connected to the top of the furnace body 10. The slag outlet 50 is connected to the bottom of the furnace body 10.

[0061] In this way, by setting the two-stage coal burner 30, dry coal powder can be introduced into the furnace body 10 above the first-stage coal burner 20, so that the dry coal powder can be pressurized and gasified into synthetic coal gas above the first-stage coal burner 20. The distribution of dry coal powder in the gasifier in the vertical direction is more uniform, which improves the utilization of the energy of the furnace body 10 and the conversion rate of the gasifier. In addition, the first-stage coal burner 20 can introduce oxygen and dry coal powder into the furnace body 10, pressurize the dry coal powder in the furnace body 10, and the synthetic coal gas can be discharged from the gas discharge port 40, and the coal slag produced after the dry coal powder is pressurized can be discharged from the coal slag discharge port 50. Therefore, the technical solution of this embodiment effectively solves the problem of low conversion rate of dry coal powder to synthetic coal gas in the related art, which causes energy waste in the gasifier.

[0062] like Figures 1 to 3As shown, there are multiple one-stage coal burners 20, and the multiple one-stage coal burners 20 are arranged at equal intervals along the circumference of the furnace body 10. The one-stage coal burner 20 includes a first pipe section 21 extending into the furnace body 10 and a second pipe section 22 penetrating the furnace body 10, and the diameter of the first pipe section 21 gradually decreases from the inside to the outside.

[0063] In other embodiments, there are multiple one-stage coal burners 20, and the multiple one-stage coal burners 20 are arranged at equal intervals along the circumference of the furnace body 10. The arrangement of multiple one-stage coal burners 20 allows oxygen and dry coal powder to pass into the furnace body 10 through the multiple one-stage coal burners 20, thereby improving the uniformity of the distribution of dry coal powder in the horizontal direction of the furnace body 10 and improving the conversion rate of dry coal powder. Alternatively, the one-stage coal burner 20 includes a first pipe section 21 extending into the furnace body 10 and a second pipe section 22 passing through the furnace body 10, and the diameter of the first pipe section 21 gradually decreases from the inside to the outside. In this way, the arrangement of the first pipe section 21 allows the dry coal powder entering the furnace body 10 from the one-stage coal burner 20 to enter the furnace body 10 more evenly, reducing the aggregation of dry coal powder and improving the conversion rate of dry coal powder. In this embodiment, there are four one-stage coal burners 20.

[0064] like Figures 1 to 3 As shown, there are two second-stage coal burners 30, and the two second-stage coal burners 30 are arranged at equal intervals along the circumference of the furnace body 10. The arrangement of multiple second-stage coal burners 30 allows dry coal powder to be passed into the furnace body 10 through the multiple second-stage coal burners 30, thereby improving the uniformity of the distribution of dry coal powder in the horizontal direction of the furnace body 10 and improving the conversion rate of dry coal powder. The second-stage coal burner 30 includes a third pipe section 31 extending into the furnace body 10 and a fourth pipe section 32 passing through the furnace body 10, and the diameter of the third pipe section 31 gradually decreases from the inside to the outside. In this way, the arrangement of the third pipe section 31 allows the dry coal powder entering the furnace body 10 from the second-stage coal burner 30 to enter the furnace body 10 more evenly, reducing the aggregation of dry coal powder and improving the conversion rate of dry coal powder.

[0065] It should be noted that “inside” refers to the inside of the furnace body 10 , and “outside” refers to the outside of the gasification furnace.

[0066] In other embodiments, there are two second-stage coal burners 30, and the two second-stage coal burners 30 are arranged at equal intervals along the circumference of the furnace body 10. Alternatively, the second-stage coal burner 30 includes a third pipe section 31 extending into the furnace body 10 and a fourth pipe section 32 penetrating the furnace body 10, and the diameter of the third pipe section 31 gradually decreases from the inside to the outside.

[0067] like Figures 1 to 5As shown, the present application also provides a method for controlling the oxygen flow rate of a first-stage coal burner of a gasifier, which is used to control the oxygen flow rate of the first-stage coal burner 20 of the gasifier. The method for controlling the oxygen flow rate of a first-stage coal burner of a gasifier comprises the following steps:

[0068] According to the load demand of the syngas product produced by the gasifier, the first pseudo load demand of the total oxygen of the gasifier is set;

[0069] According to the commissioning of the second-stage coal burner 30, the second pseudo-load demand of the total oxygen of the gasifier is set;

[0070] Determine the total oxygen load demand X of the gasifier according to the first pseudo-load demand of the total oxygen of the gasifier and the second pseudo-load demand of the total oxygen of the gasifier;

[0071] Control the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and control the total oxygen load demand X of the gasifier between a first upper limit value and a first lower limit value to obtain a corrected total oxygen load demand of the gasifier;

[0072] According to the number of the first-stage coal burners 20 and the corrected total oxygen load demand of the gasifier, the oxygen load demand Y of a single first-stage coal burner 20 is calculated;

[0073] The oxygen load demand Y of the single first-stage coal burner 20 is controlled between the second upper limit value and the second lower limit value to obtain the corrected oxygen load demand of the single first-stage coal burner 20;

[0074] The corrected oxygen load demand of a single first-stage coal burner 20 is input into the controller, and the corrected oxygen load of a single first-stage coal burner 20 is compared with the actual measured value of the oxygen flow of a single first-stage coal burner 20 to adjust the oxygen flow of the first-stage coal burner 20.

[0075] Since the above-mentioned gasifier can solve the problem of low conversion rate of dry coal powder into synthetic coal gas in the related technology, which causes energy waste of the gasifier, the oxygen flow control method of a coal burner of a gasifier used to control the oxygen flow of a coal burner 20 of the above-mentioned gasifier can solve the same technical problem.

[0076] The above method can control the oxygen load of a single first-stage coal burner 20, and enable the gasifier, the first-stage coal burner 20 and the second-stage coal burner 30 to operate below the rated value, thereby increasing the service life of the gasifier, the first-stage coal burner 20 and the second-stage coal burner 30.

[0077] In this embodiment, the total oxygen first pseudo load demand of the gasifier is set between 0% and 100% of the rated oxygen flow rate of the gasifier, that is, the range of the total oxygen first pseudo load demand of the gasifier is between 0kg / h and 55833kg / h. The total number of the first-stage coal burners 20 is n, and the oxygen load demand Y of a single first-stage coal burner 20 = the corrected total oxygen load demand of the gasifier / n. In this embodiment, n = 4.

[0078] In this embodiment, the controller is a PID regulator, and the oxygen load demand Y of a single first-stage coal burner 20 is taken as input to the PID regulator. The PID regulator performs PID operation on the oxygen load demand Y of the single first-stage coal burner 20 and the actual measured value of the oxygen flow of the single first-stage coal burner 20, and outputs an opening signal to adjust the opening of the oxygen flow control valve on the first-stage coal burner 20, so as to control the actual measured value of the oxygen flow of the single first-stage coal burner 20 to be close to the oxygen load demand Y of the single first-stage coal burner 20.

[0079] The inventors have found that the load control of the first-stage coal burner 20 can be achieved by first controlling the oxygen flow rate of the first-stage coal burner 20, and then controlling the dry coal powder flow rate according to the ratio of oxygen and dry coal powder. Alternatively, the dry coal powder flow rate of the first-stage coal burner 20 can be controlled first, and then the oxygen flow rate can be controlled according to the ratio of oxygen and dry coal powder. In this embodiment, the method of first controlling the oxygen flow rate of the first-stage coal burner 20 and then controlling the dry coal powder flow rate is adopted, because oxygen is a combustion aid and also a dangerous gas. Such a control sequence can both meet production needs and ensure equipment safety.

[0080] In this embodiment, the first pseudo load demand of total oxygen of the gasifier may be a fixed value or a function value of a parameter, such as the pressure of the gasifier or the output of downstream chemical products or the power generation load of the IGCC power plant. The first upper limit value, the first lower limit value, the second upper limit value and the second lower limit value may be fixed values ​​or variable values.

[0081] like Figures 1 to 5 As shown, according to the commissioning status of the second-stage coal burner 30, the steps of setting the second simulated total oxygen load demand of the gasifier include:

[0082] When all the second-stage coal burners 30 are not put into use, the second pseudo-load demand of total oxygen in the gasifier is set below 58% of the rated oxygen flow rate of the gasifier;

[0083] When a second-stage coal burner 30 is put into use, the second pseudo-load demand of total oxygen in the gasifier is set below 65% of the rated oxygen flow rate of the gasifier;

[0084] When the two second-stage coal burners 30 are put into use, the second pseudo-load demand of the total oxygen of the gasifier is set below 100% of the rated oxygen flow of the gasifier.

[0085] The above method can adjust the total oxygen second pseudo-load demand of the gasifier according to the number of second-stage coal burners 30 put into use, so that the gasifier and the first-stage coal burner 20 can operate below the rated value, thereby increasing the service life of the gasifier and the first-stage coal burner 20.

[0086] In this embodiment, when all the second-stage coal burners 30 are not put into use, the second pseudo-load demand of the total oxygen of the gasifier is set at 50% of the rated oxygen flow of the gasifier, or 53% of the rated oxygen flow of the gasifier, or 55% of the rated oxygen flow of the gasifier, or 57% of the rated oxygen flow of the gasifier. When one second-stage coal burner 30 is put into use, the second pseudo-load demand of the total oxygen of the gasifier is set at 60% of the rated oxygen flow of the gasifier, or 62% of the rated oxygen flow of the gasifier, or 64% of the rated oxygen flow of the gasifier. When two second-stage coal burners 30 are put into use, the second pseudo-load demand of the total oxygen of the gasifier is set at 90% of the rated oxygen flow of the gasifier, or 93% of the rated oxygen flow of the gasifier, or 97% of the rated oxygen flow of the gasifier, or 99% of the rated oxygen flow of the gasifier.

[0087] In this embodiment, the rated oxygen flow rate of the 58% gasifier is 32383 kg / h, the rated oxygen flow rate of the 65% gasifier is 36291 kg / h, and the rated oxygen flow rate of the 100% gasifier is 55833 kg / h.

[0088] like Figures 1 to 5 As shown, the steps of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than the set value, and controlling the total oxygen load demand X of the gasifier to be between the first upper limit value and the first lower limit value, and obtaining the corrected total oxygen load demand of the gasifier include:

[0089] The set value is determined based on 3% of the maximum mass flow rate of oxygen in the gasifier.

[0090] The above method can control the change rate of the total oxygen load demand of the gasifier to ensure the operation safety of the gasifier, so that oxygen can be evenly introduced into the gasifier, reduce the sudden change of oxygen flow rate, and improve the conversion rate of dry coal powder. In this embodiment, the set value is 3% of the maximum mass flow rate of oxygen in the gasifier.

[0091] like Figures 1 to 5 As shown, the steps of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than the set value, and controlling the total oxygen load demand X of the gasifier to be between the first upper limit value and the first lower limit value, and obtaining the corrected total oxygen load demand of the gasifier include:

[0092] When the gasifier pressure is less than 1 MPa, the first upper limit is determined to be 4.76 kg / s;

[0093] When 3MPa≥gasifier pressure≥1MPa, the first upper limit value is determined according to the following formula: first upper limit value=gasifier pressure×6.48-1.72;

[0094] When the gasifier pressure is greater than 3 MPa, the first upper limit is determined to be 17.72 kg / s;

[0095] When the gasifier pressure is less than 1 MPa, the first lower limit is determined to be 2.2 kg / s;

[0096] When 3MPa≥gasifier pressure≥1MPa, the first lower limit is determined according to the following formula: first lower limit=gasifier pressure×2.1+0.1;

[0097] When the gasifier pressure is greater than 3 MPa, the first lower limit is determined to be 6.4 kg / s.

[0098] The above method can adjust the total oxygen load demand X of the gasifier according to the pressure of the gasifier, so that the gasifier can be used under the specified use environment, thereby increasing the service life of the gasifier.

[0099] like Figures 1 to 5 As shown, the steps of controlling the oxygen load demand Y of a single first-stage coal burner 20 between the second upper limit and the second lower limit to obtain the corrected oxygen load demand of the single first-stage coal burner 20 include:

[0100] When the gasifier pressure is less than 1 MPa, the second upper limit is determined to be 1.38 kg / s;

[0101] When 3MPa≥gasifier pressure≥1MPa, the second upper limit value is determined according to the following formula: second upper limit value=gasifier pressure×1.425-0.045;

[0102] When the gasifier pressure is greater than 3 MPa, the second upper limit is determined to be 4.23 kg / s;

[0103] When the gasifier pressure is less than 1 MPa, the second lower limit is determined to be 1.25 kg / s;

[0104] When 3MPa≥gasifier pressure≥1MPa, the second lower limit is determined according to the following formula: second lower limit=gasifier pressure×0.18+1.07;

[0105] When the gasifier pressure is greater than 3 MPa, the second lower limit is determined to be 1.61 kg / s.

[0106] The above method can adjust the oxygen load demand Y of a single first-stage coal burner 20 according to the gasifier pressure, so that the first-stage coal burner 20 can be used in a specified use environment, thereby increasing the service life of the first-stage coal burner 20.

[0107] like Figures 1 to 5 As shown, the step of controlling the oxygen load demand Y of the single first-stage coal burner 20 between the second upper limit and the second lower limit to obtain the corrected oxygen load demand of the single first-stage coal burner 20 also includes:

[0108] When the oxygen load demand Y of the single first-stage coal burner 20 is less than the second lower limit value, the corrected oxygen load demand of the single first-stage coal burner 20 is determined as the second lower limit value;

[0109] When the oxygen load demand Y of the single first-stage coal burner 20 is greater than the second upper limit value, the corrected oxygen load demand of the single first-stage coal burner 20 is determined as the second upper limit value;

[0110] When the oxygen load demand Y of a single one-stage coal burner 20 is between the second lower limit value and the second upper limit value, the corrected oxygen load demand of the single one-stage coal burner 20 is determined as the oxygen load demand Y of the single one-stage coal burner 20 .

[0111] The above method can correct the oxygen load demand of a single first-stage coal burner 20 to increase the service life of the first-stage coal burner 20. The corrected oxygen load demand of a single first-stage coal burner 20 is calculated through proportional, integral and differential operations to obtain the corrected oxygen flow rate of the single first-stage coal burner 20 and input it into the controller.

[0112] like Figures 1 to 5 As shown, according to the first pseudo total oxygen load demand of the gasifier and the second pseudo total oxygen load demand of the gasifier, the step of determining the total oxygen load demand X of the gasifier includes:

[0113] The minimum value of the first pseudo-load demand of total oxygen in the gasifier and the second pseudo-load demand of total oxygen in the gasifier is taken as the total oxygen load demand X of the gasifier.

[0114] The above method can enable the gasifier to work below the rated value, thereby increasing the service life of the gasifier and safely protecting the use of the gasifier.

[0115] The inventors have found that the oxygen flow control of the first-stage coal burner 20 is an important factor in producing qualified synthetic coal gas. In order to ensure the safe, economical and stable operation of the gasifier, the load control of the first-stage coal burner 20 and the second-stage coal burner 30 is very important. The load control of the first-stage coal burner 20 and the second-stage coal burner 30 includes the oxygen flow control and the dry coal powder flow control entering the first-stage coal burner 20 and the second-stage coal burner 30. Among them, the oxygen flow control is the main variable. By changing the oxygen flow rate, the ratio of oxygen and dry coal powder can be changed to control the dry coal powder flow rate.

[0116] In this embodiment, a first reaction zone is formed in the furnace body 10 near the first-stage coal burner 20, and a second reaction zone is formed in the furnace body 10 near the second-stage coal burner 30. The first reaction zone is the main reaction zone of the dry coal powder. The first-stage coal burner 20 is provided with a first regulating valve 23 and a second regulating valve 24. Oxygen enters the furnace body 10 through the first regulating valve 23, and the dry coal powder enters the furnace body 10 through the second regulating valve 24. Oxygen and dry coal powder are mixed and burned, and a series of chemical reactions are performed to generate synthetic coal gas whose main components are carbon monoxide and hydrogen, which is sent to the downstream process as the product gas of the gasifier. After the dry coal powder in the gasifier is burned, coal slag is formed at the bottom and discharged to the slag collection tank 60, and then discharged to the outside by the slag collection tank 60. A third regulating valve 33 is provided on the second-stage coal burner 30, and the dry coal powder enters the second-stage reaction zone of the furnace body 10 through the third regulating valve 33. The dry coal powder in the second-stage reaction zone reacts chemically with the high-temperature gas from the first-stage reaction zone again to produce synthetic coal gas, thereby improving the conversion rate of the dry coal powder in the gasification furnace.

[0117] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0118] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0119] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gasifier, characterized in that: include: Furnace body (10); A coal burner (20) connected to the side wall of the furnace body (10); A second-stage coal burner (30) connected to the side wall of the furnace body (10) and located above the first-stage coal burner (20); A gas exhaust port (40) connected to the top of the furnace body (10); The slag discharge port (50) is connected to the bottom of the furnace body (10).

2. The gasifier according to claim 1, characterized in that: There are a plurality of the first-stage coal burners (20), and the plurality of first-stage coal burners (20) are arranged at equal intervals along the circumference of the furnace body (10); and / or, The one-stage coal burner (20) comprises a first pipe section (21) extending into the furnace body (10) and a second pipe section (22) penetrating the furnace body (10), wherein the diameter of the first pipe section (21) gradually decreases from the inside to the outside.

3. The gasifier according to claim 1, characterized in that: There are two second-stage coal burners (30), and the two second-stage coal burners (30) are arranged at equal intervals along the circumference of the furnace body (10); and / or, The two-stage coal burner (30) comprises a third pipe section (31) extending into the furnace body (10) and a fourth pipe section (32) penetrating the furnace body (10), and the diameter of the third pipe section (31) gradually decreases from the inside to the outside.

4. A method for controlling the oxygen flow rate of a first-stage coal burner of a gasifier, characterized in that: The method for controlling the oxygen flow rate of a first-stage coal burner (20) of a gasifier according to any one of claims 1 to 3 comprises the following steps: According to the load demand of the syngas product produced by the gasifier, the first pseudo load demand of the total oxygen of the gasifier is set; According to the commissioning status of the second-stage coal burner (30), the second pseudo-load demand of the total oxygen of the gasifier is set; Determine the total oxygen load demand X of the gasifier according to the first pseudo-load demand of the total oxygen of the gasifier and the second pseudo-load demand of the total oxygen of the gasifier; Control the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and control the total oxygen load demand X of the gasifier between a first upper limit value and a first lower limit value to obtain a corrected total oxygen load demand of the gasifier; According to the number of the first-stage coal burners (20) and the corrected total oxygen load demand of the gasifier, the oxygen load demand Y of a single first-stage coal burner (20) is calculated; Controlling the oxygen load demand Y of a single first-stage coal burner (20) between a second upper limit value and a second lower limit value to obtain a corrected oxygen load demand of the single first-stage coal burner (20); The corrected oxygen load requirement of a single first-stage coal burner (20) is input into a controller, the corrected oxygen load of the single first-stage coal burner (20) is compared with an actual measured value of the oxygen flow rate of the single first-stage coal burner (20), and the oxygen flow rate of the first-stage coal burner (20) is adjusted.

5. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 4, characterized in that: The step of setting the second simulated total oxygen load requirement of the gasifier according to the commissioning status of the second-stage coal burner (30) comprises: When all the second-stage coal burners (30) are not put into use, the second pseudo-load demand of total oxygen in the gasifier is set below 58% of the rated oxygen flow rate of the gasifier; When a second-stage coal burner (30) is put into use, the second pseudo-load demand of the total oxygen of the gasifier is set below 65% of the rated oxygen flow of the gasifier; When the two second-stage coal burners (30) are put into use, the second pseudo-load demand of the total oxygen of the gasifier is set below 100% of the rated oxygen flow of the gasifier.

6. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 4, characterized in that: The step of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and controlling the total oxygen load demand X of the gasifier to be between a first upper limit value and a first lower limit value, and obtaining a corrected total oxygen load demand of the gasifier comprises: The set value is determined based on 3% of the maximum mass flow rate of oxygen in the gasifier.

7. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 4, characterized in that: The step of controlling the change rate of the total oxygen load demand of the gasifier to be not greater than a set value, and controlling the total oxygen load demand X of the gasifier to be between a first upper limit value and a first lower limit value, and obtaining a corrected total oxygen load demand of the gasifier comprises: When the gasifier pressure is less than 1 MPa, the first upper limit is determined to be 4.76 kg / s; When 3MPa≥gasifier pressure≥1MPa, the first upper limit value is determined according to the following formula: first upper limit value=gasifier pressure×6.48-1.72; When the gasifier pressure is greater than 3 MPa, the first upper limit is determined to be 17.72 kg / s; When the gasifier pressure is less than 1 MPa, the first lower limit is determined to be 2.2 kg / s; When 3MPa≥gasifier pressure≥1MPa, the first lower limit is determined according to the following formula: first lower limit=gasifier pressure×2.1+0.1; When the gasifier pressure is greater than 3 MPa, the first lower limit is determined to be 6.4 kg / s.

8. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 4, characterized in that: The step of controlling the oxygen load demand Y of the single first-stage coal burner (20) between the second upper limit value and the second lower limit value to obtain the corrected oxygen load demand of the single first-stage coal burner (20) comprises: When the gasifier pressure is less than 1 MPa, the second upper limit is determined to be 1.38 kg / s; When 3MPa≥gasifier pressure≥1MPa, the second upper limit value is determined according to the following formula: second upper limit value=gasifier pressure×1.425-0.045; When the gasifier pressure is greater than 3 MPa, the second upper limit is determined to be 4.23 kg / s; When the gasifier pressure is less than 1 MPa, the second lower limit is determined to be 1.25 kg / s; When 3MPa≥gasifier pressure≥1MPa, the second lower limit is determined according to the following formula: second lower limit=gasifier pressure×0.18+1.07; When the gasifier pressure is greater than 3 MPa, the second lower limit is determined to be 1.61 kg / s.

9. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 8, characterized in that: The step of controlling the oxygen load demand Y of the single first-stage coal burner (20) between the second upper limit value and the second lower limit value to obtain the corrected oxygen load demand of the single first-stage coal burner (20) further comprises: When the oxygen load demand Y of a single first-stage coal burner (20) is less than a second lower limit value, the corrected oxygen load demand of the single first-stage coal burner (20) is determined as the second lower limit value; When the oxygen load demand Y of a single first-stage coal burner (20) is greater than a second upper limit value, the corrected oxygen load demand of the single first-stage coal burner (20) is determined as the second upper limit value; When the oxygen load demand Y of a single one-stage coal burner (20) is between the second lower limit value and the second upper limit value, the corrected oxygen load demand Y of the single one-stage coal burner (20) is determined as the oxygen load demand Y of the single one-stage coal burner (20).

10. The method for controlling oxygen flow rate of a first-stage coal burner of a gasifier according to claim 4, characterized in that: The step of determining the total oxygen load demand X of the gasifier according to the first simulated total oxygen load demand of the gasifier and the second simulated total oxygen load demand of the gasifier comprises: The minimum value of the first pseudo-load demand of total oxygen in the gasifier and the second pseudo-load demand of total oxygen in the gasifier is taken as the total oxygen load demand X of the gasifier.

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