A garbage flow classification control method

Abstract

The present invention discloses a method for controlling the flow rate of garbage in a cement kiln decomposition furnace, which is used for the incineration garbage input system of the cement kiln decomposition furnace. The incineration garbage input system includes a plate feeder, a pair of reamers, and a belt scale, and includes the following steps: step 1, calculating the deviation between the actual garbage flow rate and the garbage flow rate setting value, and adjusting the belt scale speed according to the deviation; step 2, dynamically adjusting the speeds of the two reamers according to the belt scale speed obtained in step 1; step 3, dynamically adjusting the plate feeder speed according to the reamer speed obtained in step 2. The present invention adopts a garbage flow rate classification control for the garbage conveying device of the cement kiln decomposition furnace, which can stabilize the garbage flow rate and effectively reduce the fluctuation of the garbage flow rate.

Description

Technical Field

[0001] The invention relates to the field of cement kiln decomposition furnace control methods, in particular to a cement kiln decomposition furnace garbage flow classification control method. Background Art

[0002] The treatment of urban domestic waste has gone through different stages from landfill to incineration (including waste incineration power generation) to waste-cement kiln co-treatment. The technology of using cement kilns to co-treat urban waste, sludge and hazardous waste has been internationally recognized as the most effective and safest method. Compared with other methods of waste disposal, cement kiln co-treatment has the comparative advantages of energy saving, environmental protection and economy, and is currently an important means of waste disposal in the world.

[0003] The garbage conveying device of the existing cement kiln decomposition furnace is as follows Figure 1 As shown, it generally includes a plate feeder 1, a reamer pair, a feed wheel 4, and a belt scale 5. The first reamer 2 and the second reamer 3 are symmetrically distributed in the reamer pair. The plate feeder 1, the first reamer 2, the second reamer 3, the feed wheel 4, and the belt scale 5 are respectively controlled by their own motors. The garbage output by the plate feeder 1 is fed to between the first reamer 2 and the second reamer 3 by the feed wheel 4, and is shredded by the first reamer 2 and the second reamer 3 and transported to the belt scale 5. Finally, it is transported to the cement kiln decomposition furnace for incineration through the belt scale 5. Due to the different sizes and weights of garbage, the garbage flow rate of the existing garbage conveying device is unstable, which will cause the problem of large temperature fluctuations in the cement kiln decomposition furnace, affecting the quality of cement. Summary of the invention

[0004] The purpose of the present invention is to provide a method for controlling the flow rate of garbage in a cement kiln decomposition furnace by grading, so as to solve the problem of unstable flow rate of garbage transported by a garbage transport device in a cement kiln decomposition furnace in the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for controlling the flow rate of garbage in a cement kiln decomposition furnace by grading is used for the incineration garbage input system of the cement kiln decomposition furnace. The incineration garbage input system includes a plate feeder, a pair of reamers, and a belt scale. The incineration garbage is transported to the reamers by the plate feeder, and then shredded by two reamers and transported to the belt scale. Finally, it is transported to the cement kiln decomposition furnace by the belt scale for incineration, and includes the following steps:

[0007] Step 1: Real-time collection of the actual waste flow W delivered by the belt scale to the cement kiln decomposition furnace LJ (k), find the actual garbage flow W LJ (k) and the garbage flow setting value W SP (k) Deviation ΔW between LJ (k) = W SP (k)-WLJ (k), according to the deviation ΔW LJ (k) Use PID control algorithm to adjust the belt scale speed ω pdc (k) To achieve the first level of stable control of garbage flow;

[0008] Step 2: Belt scale speed ω obtained from step 1 pdc (k), dynamically adjust the speeds of the two reamers according to formulas (1) and (2) to achieve the second level of stable control of the garbage flow. Suppose the speed of the first reamer is ω g1 , the second reamer speed is ω g2 , formulas (1) and (2) are as follows:

[0009] ω g1 =k 1,i ×ω pdc +k 2,i (1)

[0010] ω g2 =ω g1 +k 3,i (2)

[0011] In formulas (1) and (2), the parameter k 1,i , k 2,i , k 3,i To set coefficients according to different garbage flows;

[0012] Step 3: The first reamer speed ω obtained in step 2 g1 Or the second reamer speed ω g2 , dynamically adjust the plate feeder speed ω according to formula (3) or formula (4) bwh , to achieve the third level of stable control of garbage flow, formulas (3) and (4) are as follows:

[0013] ω bwj =k 4,i ×ω g1 +k 5,i (3)

[0014] ω bwj =k 6,i ×ω g1 +k 7,i (4)

[0015] In formulas (3) and (4), the parameter k 4,i , k 5,i , k 6,i , k 7,i It is a setting coefficient according to different garbage flow rates.

[0016] In a further step 1, the deviation ΔW is obtained LJ(k), the PID control algorithm is used to adjust the belt scale speed ω pdc (k), calculate the belt scale speed ω according to the following formula pdc (k):

[0017] ω pdc (k) = ω pdc (k-1)+Δω pdc (k)

[0018] Δω pdc (k) = K p (ΔW LJ (k)-ΔW LJ (k-1))+K i ΔW LJ (k)+K d (ΔW LJ (k)-2ΔW LJ (k-1)+ΔW LJ (k-2)),

[0019] Among them, K p , K i , K d is the PID parameter.

[0020] In the further step 2, the parameter k is selected 1,i , k 2,i , k 3,i To ensure that the waste flow rate entering the reamer and the waste flow rate leaving the reamer remain constant, the waste flow rate is divided into three levels: large, medium, and small. The parameter k 1,i , k 2,i , k 3,i It is also divided into three grades: large, medium and small.

[0021] In the further step 3, the parameter k is selected 4,i , k 5,i , k 6,i , k 7,i To ensure that the garbage flow rate entering the plate feeder and the garbage flow rate leaving the plate feeder remain constant, the garbage flow rate is divided into three levels: large, medium and small. The parameter k 4,i , k 5,i , k 6,i , k 7,i It is also divided into three grades: large, medium and small.

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] The present invention adopts garbage flow classification control for the garbage conveying device of the cement kiln decomposition furnace, which can stabilize the garbage flow. The real-time garbage flow is adjusted online in a graded manner by adjusting the speed of the plate feeder, the speeds of two reamers, and the speed of the belt scale, which can effectively reduce the fluctuation of the garbage flow, improve the stability of the garbage flow, and further improve the temperature stability of the cement kiln decomposition furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The utility model is a structural principle diagram of a garbage conveying device of a cement kiln decomposition furnace in the prior art. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] The method of this embodiment is used to control the incineration garbage input system of the cement kiln decomposition furnace, specifically by controlling the plate feeder speed, the two reamer speeds, and the speed of the belt scale to obtain a stable garbage flow. This embodiment uses specific numerical values ​​to illustrate the method of this embodiment, including the following steps:

[0027] Step 1: Set the garbage flow setting value W SP (k), garbage flow setting value W SP (k) can be set manually. In a cement plant, the value range is [5,20]. The large garbage flow is [15,20], the medium garbage flow is [10,15], and the small garbage flow is [5,10]. Real-time collection of the actual garbage flow W delivered by the belt scale to the cement kiln decomposition furnace LJ (k), calculate the actual garbage flow W LJ (k) and the garbage flow setting value W SP (k) Deviation ΔW between LJ (k) = W SP (k)-W LJ (k).

[0028] According to the deviation ΔW LJ (k) Use PID control algorithm to adjust the belt scale speed ω pdc (k) To achieve the first level of stable control of the garbage flow, the PID control algorithm adjusts the belt scale speed as follows:

[0029] Δω pdc (k) = K p (ΔW LJ (k)-ΔW LJ (k-1))+K i ΔW LJ (k)+K d (ΔW LJ (k)-2ΔW LJ (k-1)+ΔW LJ (k-2)),

[0030] Among them, K p , K i , K d is the PID parameter.

[0031] After adjustment, the belt scale speed ω pdc (k) is:

[0032] ω pdc (k) = ω pdc (k-1)+Δω pdc (k)

[0033] Step 2: Belt scale speed ω obtained from step 1 pdc (k), dynamically adjust the speeds of the two reamers according to formulas (1) and (2) to achieve the second level of stable control of the garbage flow. Suppose the speed of the first reamer is ω g1 , the second reamer speed is ω g2 , formulas (1) and (2) are as follows:

[0034] ω g1 =k 1,i ×ω pdc +k 2,i (1)

[0035] ω g2 =ω g1 +k 3,i (2)

[0036] In formulas (1) and (2), the parameter k 1,i , k 2,i , k 3,i is the setting coefficient according to different garbage flow, where: select parameter k 1,i , k 2,i , k 3,i The value is to ensure that the garbage flow entering the reamer and the garbage flow leaving the reamer remain constant. The garbage flow is divided into three levels: large, medium and small. Then the parameter k 1,i , k 2,i , k 3,i It is also divided into three grades: large, medium and small.

[0037] In a cement plant, the value is

[0038] Junk traffic <![CDATA[k 1,i ]]> <![CDATA[k 2,i ]]> <![CDATA[k 3,i ]]> big 1.32 310 50 middle 1.3 280 50 Small 1.35 300 50

[0039] Substituting the specific values ​​into formulas (1) and (2), the first reamer speed is calculated to be ω g1 , the second reamer speed is ω g2 .

[0040] Step 3: The first reamer speed ω obtained in step 2 g1 Or the second reamer speed ω g2 , dynamically adjust the plate feeder speed ω according to formula (3) or (4) bwj , to achieve the third level of stable control of garbage flow, formula (3) or (4) is as follows:

[0041] ω bwj =k 4,i ×ω g1 +k 5,i (3)

[0042] ω bwj =k 6,i ×ω g1 +k 7,i (4)

[0043] In formulas (3) and (4), the parameter k 4,i , k 5,i , k 6,i , k 7,i is the setting coefficient according to different garbage flow, where: select parameter k 4,i , k 5,i , k 6,i , k 7,i The value is to ensure that the garbage flow entering the plate feeder and the garbage flow leaving the plate feeder remain constant. The garbage flow is divided into three levels: large, medium and small. The parameter k 4,i , k 5,i , k 6,i , k 7,i It is also divided into three grades: large, medium and small.

[0044] Taking formula (3) as an example, formula (3) is used in a cement plant, and the values ​​are shown in Table 1:

[0045] Table 1 Value table of formula (3)

[0046] Junk traffic <![CDATA[k 4,i ]]> <![CDATA[k 5,i ]]> big 0.9 30 middle 0.9 35 Small 0.95 35

[0047] Substituting the specific value into formula (3), we can calculate the plate feeder speed ω bwj .

[0048] Therefore, through steps 1 to 3, the speed of the plate feeder, the two reamers, and the belt scale can be controlled to achieve a stable garbage flow rate.

[0049] Uneven feeding of domestic combustible garbage will affect the temperature fluctuation of the decomposition furnace and cause abnormal operation of the cement kiln. Since the requirements for garbage particle size are not high and the garbage properties vary greatly, the conventional belt scale metering scale will have a large error. Therefore, the present invention uses a belt scale, a reamer, and a plate feeder to jointly control the feeding of domestic combustible garbage, and adopts hierarchical control to improve the stability of feeding.

[0050] The embodiments described in the present invention are merely descriptions of the preferred implementation modes of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made to the technical solutions of the present invention by engineers and technicians in this field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have all been recorded in the claims.

Claims

1. A method for controlling the flow rate of garbage in a cement kiln decomposition furnace by grading is used for the incineration garbage input system of the cement kiln decomposition furnace. The incineration garbage input system includes a plate feeder, a pair of reamers, and a belt scale. The incineration garbage is transported to the reamers by the plate feeder, and then minced by two reamers and transported to the belt scale. Finally, it is transported to the cement kiln decomposition furnace by the belt scale for incineration. The method is characterized in that: The following steps are involved: Step 1: Real-time collection of the actual waste flow W delivered by the belt scale to the cement kiln decomposition furnace LJ (k), find the actual garbage flow W LJ (k) and the garbage flow setting value W SP (k) Deviation ΔW between LJ (k) = W SP (k)-W LJ (k), according to the deviation ΔW LJ (k) Use PID control algorithm to adjust the belt scale speed ω pdc (k) To achieve the first level of stable control of garbage flow; Step 2: Belt scale speed ω obtained from step 1 pdc (k), dynamically adjust the speeds of the two reamers according to formulas (1) and (2) to achieve the second level of stable control of the garbage flow. Suppose the speed of the first reamer is ω g1 , the second reamer speed is ω g2 , formulas (1) and (2) are as follows: oh g1 =k 1，i ×ω pdc +k 2，i (1), oh g2 =ω g1 +k 3，i (2), In formulas (1) and (2), the parameter k 1，i , k 2，i , k 3，i To set coefficients according to different garbage flows; Step 3: The first reamer speed ω obtained in step 2 g1 Or the second reamer speed ω g2 , dynamically adjust the plate feeder speed ω according to formula (3) or formula (4) bwj , to achieve the third level of stable control of garbage flow, formulas (3) and (4) are as follows: oh bwj =k 4，i ×ω g1 +k 5，i (3), oh bwj =k 6，i ×ω g1 +k 7，i (4) In formulas (3) and (4), the parameter k 4，i , k 5，i , k 6，i , k 7，i It is a setting coefficient according to different garbage flow rates.

2. A cement kiln decomposition furnace garbage flow classification control method according to claim 1, characterized in that: In step 1, obtain the deviation ΔW LJ (k), the PID control algorithm is used to adjust the belt scale speed ω pdc (k), calculate the belt scale speed ω according to the following formula pdc (k): oh pdc (k)=ω pdc (k-1)+Do pdc (k), Give pdc (k)=K p (ΔW LJ (k)-ΔW LJ (k-1))+K i ΔW LJ (k)+K d (ΔW LJ (k)-2ΔW LJ (k-1)+ΔW LJ (k-2)), Among them, K p , K i , K d is the PID parameter.

3. A cement kiln decomposition furnace garbage flow classification control method according to claim 1, characterized in that: In step 2, select parameter k 1，i , k 2，i , k 3，i To ensure that the waste flow rate entering the reamer and the waste flow rate leaving the reamer remain constant, the waste flow rate is divided into three levels: large, medium, and small. The parameter k 1，i , k 2，i , k 3，i It is also divided into three grades: large, medium and small.

4. A cement kiln decomposition furnace garbage flow classification control method according to claim 1, characterized in that: In step 3, select parameter k 4，i , k 5，i , k 6，i , k 7，i To ensure that the garbage flow rate entering the plate feeder and the garbage flow rate leaving the plate feeder remain constant, the garbage flow rate is divided into three levels: large, medium and small. The parameter k 4，i , k 5，i , k 6，i , k 7，i It is also divided into three grades: large, medium and small.

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