阅读说明：本技术 一种燃煤锅炉最大污泥掺烧量的计算方法及系统 (Method and system for calculating maximum sludge blending combustion amount of coal-fired boiler ) 是由 童家麟 齐晓娟 吕洪坤 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种燃煤锅炉最大污泥掺烧量的计算方法及系统。本发明的方法包括：分别计算典型负荷下燃煤锅炉最低炉膛温度承受值的目标最大污泥掺烧量,磨煤机燃料量最大承受值的目标最大污泥掺烧量,脱硝系统NO最大承受值的目标最大污泥掺烧量,脱硫系统SO-(2)最大承受值的目标最大污泥掺烧量,除尘系统粉尘最大承受值的目标最大污泥掺烧量,废水系统重金属最大可排放值的目标最大污泥掺烧量,取各个目标最大污泥掺烧量中的最小值,根据燃煤机组目标发电功率和实际发电功率实时修正最小值后为燃煤锅炉最大污泥掺烧量。本发明在保证燃煤机组发电功率及燃煤锅炉安全运行的前提下,最大程度地提高典型负荷下污泥可掺烧量。(The invention discloses a method and a system for calculating the maximum sludge co-combustion amount of a coal-fired boiler. The method of the invention comprises the following steps: respectively calculating the target maximum sludge blending combustion amount of the lowest hearth temperature bearing value of the coal-fired boiler, the target maximum sludge blending combustion amount of the maximum fuel quantity bearing value of the coal mill, the target maximum sludge blending combustion amount of the maximum NO bearing value of the denitration system and the SO of the desulfurization system under typical load 2 The method comprises the steps of obtaining a target maximum sludge blending combustion amount with a maximum bearing value, a target maximum sludge blending combustion amount with a maximum dust bearing value of a dust removal system and a target maximum sludge blending combustion amount with a maximum discharge value of heavy metals of a wastewater system, taking the minimum value of the target maximum sludge blending combustion amounts, correcting the minimum value in real time according to the target power generation power and the actual power generation power of a coal-fired unit, and then obtaining the maximum sludge blending combustion amount of the coal-fired boiler. The invention is in ensuring combustionThe method has the advantages that the sludge mixable combustion amount under typical load is improved to the maximum extent on the premise of generating power of the coal unit and safe operation of the coal-fired boiler.)

1. A method for calculating the maximum sludge blending combustion amount of a coal-fired boiler is characterized by comprising the following steps of:

step 1, acquiring relevant parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under a typical load;

step 2, calculating a first target maximum sludge co-combustion amount of the lowest hearth temperature bearing value of the coal-fired boiler under a typical load;

step 3, calculating a second target maximum sludge blending combustion amount of the maximum fuel bearing value of the coal mill under the typical load;

step 4, calculating a third target maximum sludge co-combustion amount of the maximum NO bearing value of the denitration system under a typical load;

step 5, calculating the SO of the desulfurization system under the typical load₂The fourth target maximum sludge mixed combustion amount of the maximum bearing value;

step 6, calculating the fifth target maximum sludge co-combustion amount of the dust maximum bearing value of the dust removal system under the typical load;

step 7, respectively calculating the sludge co-combustion amount of the maximum dischargeable value of each heavy metal in the wastewater system under the typical load, wherein the minimum value is the sixth target maximum sludge co-combustion amount;

step 8, comparing the first target maximum sludge blending combustion amount, the second target maximum sludge blending combustion amount, the third target maximum sludge blending combustion amount, the fourth target maximum sludge blending combustion amount, the fifth target maximum sludge blending combustion amount and the sixth target maximum sludge blending combustion amount, and taking the minimum value as the target maximum sludge blending combustion amount of the coal-fired boiler under the typical load;

and 9, correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

2. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the calculation formula of the first target maximum sludge co-combustion amount under the typical load is as follows:

wherein A is the total fuel quantity, and the unit is: kg/h; t is₁The lowest furnace temperature bearable value of the coal-fired boiler is represented by the unit: k; t is₂The hearth temperature during the combustion of the whole coal has the unit: k; t is₃The unit is the influence value of the sludge on the hearth temperature: K.

3. the method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the second target maximum sludge co-combustion amount under the typical load is calculated according to the following two formulas:

in the formula, Q₁The heat release required by the hearth is as follows: kJ/h; b is the maximum grinding amount of a single coal mill, and the unit is as follows: kg/h; n is the number of coal mills in operation; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The unit is the lower heating value of the sludge and is as follows: kJ/kg; f is the primary air volume of a single coal mill, and the unit is as follows: kg/h; c is the air specific heat, and the unit is: kJ/(kg. K); t is t₁The unit is the primary air temperature at the inlet of the coal mill: k; t is t₂The lowest allowable primary air temperature of the outlet of the coal mill is represented by the following unit: k; γ is the latent heat of vaporization of water in units of: kJ/kg; w is a₁Water content outside coal,%; w is a₂Is the external water content of the sludge,%;

and measuring the second target maximum sludge mixed combustion amount to obtain the smaller value of the calculation results of the two formulas.

4. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the calculation formula of the third target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, N₁The maximum NO bearing value of the denitration system is expressed by the following unit: kg/h; a is the total fuel quantity, with the unit: kg/h; n is a radical of₂Generating NO coefficients for the coal; n is a radical of₃Generating NO coefficients for the sludge.

5. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the calculation formula of the fourth target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, S₁For desulfurization system SO₂Maximum tolerated value, in units of: kg/h; a is the total fuel quantity, with the unit: kg/h; s₂Generating SO for coal₂A coefficient; s₃Generating SO for sludge₂And (4) the coefficient.

6. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the calculation formula of the fifth target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, V₁The unit is the maximum bearing value of dust of a dust removal system: kg/h; a is the total fuel quantity, with the unit: kg/h; v₂Ash content in coal,%; v₃Is the ash content in the sludge,％。

7. the method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the calculation formula of the sixth maximum sludge co-combustion amount under the typical load is as follows:

in the formula, M₁The maximum dischargeable value of various heavy metals in a wastewater system is as follows: kg/h; a is the total fuel quantity, with the unit: kg/h; m₂The mass fraction of various heavy metals in the coal is percent; m₃The mass fraction of each heavy metal in the sludge is percent;

respectively calculating respective x according to the maximum dischargeable value of various heavy metals in the wastewater system₆And the minimum value is the sixth target maximum sludge co-combustion amount.

8. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to claim 1, wherein the real-time correction formula of the maximum sludge co-combustion amount of the coal-fired boiler under the typical load is as follows:

in the formula, D₁The unit is the actual generated power: kJ/h; d₂The unit is the target generated power: kJ/h; x is the number of₇The unit of the maximum sludge mixed combustion amount is as follows: kg/h; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The unit is the lower heating value of the sludge and is as follows: kJ/kg.

9. The method for calculating the maximum sludge co-combustion amount of the coal-fired boiler according to any one of claims 2 and 4 to 8, wherein the total fuel amount A is the sum of the coal amount and the sludge amount.

10. A system for calculating the maximum sludge blending combustion amount of a coal-fired boiler is characterized by comprising:

the system comprises a parameter acquisition unit, a data processing unit and a data processing unit, wherein the parameter acquisition unit is used for acquiring related parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under typical load;

the first target maximum sludge mixed combustion amount calculating unit calculates a first target maximum sludge mixed combustion amount according to the lowest hearth temperature bearing value of the coal-fired boiler under the typical load;

the second target maximum sludge mixed combustion amount calculating unit calculates a second target maximum sludge mixed combustion amount according to the maximum fuel amount bearing value of the coal mill under the typical load;

the third target maximum sludge co-combustion amount calculating unit calculates a third target maximum sludge co-combustion amount according to the maximum NO bearing value of the denitration system under the typical load;

a fourth target maximum sludge mixed combustion amount calculation unit for calculating the SO of the desulfurization system under the typical load₂Calculating the fourth target maximum sludge blending combustion amount according to the maximum bearing value;

the fifth target maximum sludge mixed combustion amount calculation unit calculates a fifth target maximum sludge mixed combustion amount according to the maximum dust bearing value of the dust removal system under the typical load;

the sixth target maximum sludge mixed combustion amount calculation unit calculates the sixth target maximum sludge mixed combustion amount according to the maximum dischargeable value of various heavy metals of the wastewater system under the typical load;

the maximum sludge blending combustion amount calculation unit is used for comparing the first target maximum blending combustion amount, the second target maximum blending combustion amount, the third target maximum blending combustion amount, the fourth target maximum blending combustion amount, the fifth target maximum blending combustion amount and the sixth target maximum blending combustion amount, and obtaining the target maximum sludge blending combustion amount by taking the minimum value; and correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

Technical Field

The invention belongs to the technical field of sludge utilization of coal-fired boilers, and particularly relates to a method and a system for calculating the maximum sludge co-combustion amount of a coal-fired boiler.

Background

Along with the continuous acceleration of the urbanization construction process in China, the generation amount of urban sludge is obviously increased, and the sludge treatment amount is greatly increased. At present, the methods for treating sludge generally include land landfill, direct sea drainage, direct incineration, mixed combustion treatment and the like, among the above treatment methods, the incineration method can completely combust and carbonize organic matters in the sludge, and the treatment speed is high and the treatment is thorough, so that the methods are widely regarded in recent years. Among various incineration modes, the mixed combustion treatment of the sludge of the coal-fired boiler has the advantages of small initial investment, small usage amount of auxiliary fuel and the like, and is considered to be a promising treatment method.

The temperature of a hearth can be reduced after the sludge of the conventional coal-fired boiler is co-fired, the NO treatment capacity of a denitration system and the SO of a desulfurization system can be reduced₂The method has the advantages that the treatment capacity, the dust treatment capacity of a dust removal system, the heavy metal discharge amount of a wastewater system and the like are increased, the sludge co-combustion amount of the coal-fired boiler is limited to a certain extent, the traditional maximum sludge co-combustion amount is usually obtained only by experience, certain blindness exists, and the actual maximum sludge co-combustion amount is usually greatly lower than the bearable value of the coal-fired boiler.

Disclosure of Invention

In view of the above, the invention provides a method and a system for calculating the maximum sludge co-combustion amount of a coal-fired boiler, which can improve the sludge co-combustion amount under a typical load to the maximum extent on the premise of ensuring the safe operation of the coal-fired boiler according to the related parameters and sludge characteristics of the coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dedusting system and a wastewater system under the typical load, and can correct the maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of a coal-fired unit.

In order to achieve the purpose, the invention adopts the following technical scheme: a method for calculating the maximum sludge blending combustion amount of a coal-fired boiler comprises the following steps:

step 1, acquiring relevant parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under a typical load;

step 2, calculating a first target maximum sludge co-combustion amount of the lowest hearth temperature bearing value of the coal-fired boiler under a typical load;

step 3, calculating a second target maximum sludge blending combustion amount of the maximum fuel bearing value of the coal mill under the typical load;

step 4, calculating a third target maximum sludge co-combustion amount of the maximum NO bearing value of the denitration system under a typical load;

step 5, calculating the SO of the desulfurization system under the typical load₂The fourth target maximum sludge mixed combustion amount of the maximum bearing value;

step 6, calculating the fifth target maximum sludge co-combustion amount of the dust maximum bearing value of the dust removal system under the typical load;

step 7, respectively calculating the sludge co-combustion amount of the maximum dischargeable value of each heavy metal in the wastewater system under the typical load, wherein the minimum value is the sixth target maximum sludge co-combustion amount;

step 8, comparing the first target maximum sludge blending combustion amount, the second target maximum sludge blending combustion amount, the third target maximum sludge blending combustion amount, the fourth target maximum sludge blending combustion amount, the fifth target maximum sludge blending combustion amount and the sixth target maximum sludge blending combustion amount, and taking the minimum value as the target maximum sludge blending combustion amount of the coal-fired boiler under the typical load;

and 9, correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

Further, the calculation formula of the first target maximum sludge co-combustion amount under the typical load is as follows:

wherein A is the total fuel quantity, and the unit is: kg/h; t is₁The lowest furnace temperature bearable value of the coal-fired boiler is represented by the unit: k; t is₂The hearth temperature during the combustion of the whole coal has the unit: k; t is₃The unit is the influence value of the sludge on the hearth temperature: K.

further, the second target maximum sludge co-combustion amount under the typical load is calculated according to the following two formulas:

in the formula, Q₁The heat release required by the hearth is as follows: kJ/h; b is the maximum grinding amount of a single coal mill, and the unit is as follows: kg/h; n is the number of coal mills in operation; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The unit is the lower heating value of the sludge and is as follows: kJ/kg; f is the primary air volume of a single coal mill, and the unit is as follows: kg/h; c is the air specific heat, and the unit is: kJ/(kg. K); t is t₁The unit is the primary air temperature at the inlet of the coal mill: k; t is t₂The lowest allowable primary air temperature of the outlet of the coal mill is represented by the following unit: k; γ is the latent heat of vaporization of water in units of: kJ/kg; w is a₁Water content outside coal,%; w is a₂Is the external water content of the sludge,%;

and measuring the second target maximum sludge mixed combustion amount to obtain the smaller value of the calculation results of the two formulas.

Further, the calculation formula of the third target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, N₁The maximum NO bearing value of the denitration system is expressed by the following unit: kg/h; a is the total fuel quantity, with the unit: kg/h; n is a radical of₂Generating NO coefficients for the coal; n is a radical of₃Generating NO coefficients for the sludge.

Further, the calculation formula of the fourth target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, S₁For desulfurization system SO₂Maximum tolerated value, in units of: kg/h; a is the total fuel quantity, with the unit: kg/h; s₂Generating SO for coal₂A coefficient; s₃Generating SO for sludge₂And (4) the coefficient.

Further, the calculation formula of the fifth target maximum sludge co-combustion amount under the typical load is as follows:

in the formula, V₁The unit is the maximum bearing value of dust of a dust removal system: kg/h; a is the total fuel quantity, with the unit: kg/h; v₂Ash content in coal,%; v₃Is the ash content in the sludge.

Further, the calculation formula of the sixth maximum sludge co-combustion amount under the typical load is as follows:

in the formula, M₁The maximum dischargeable value of various heavy metals in a wastewater system is as follows: kg/h; a is the total fuel quantity, with the unit: kg/h; m₂The mass fraction of various heavy metals in the coal is percent; m₃The mass fraction of each heavy metal in the sludge is percent;

respectively calculating x according to the maximum discharge value of various heavy metals in the wastewater system₆And the minimum value is the sixth target maximum sludge co-combustion amount.

Further, the real-time correction formula of the maximum sludge co-combustion amount of the coal-fired boiler under the typical load is as follows:

in the formula, D₁The unit is the actual generated power: kJ/h; d₂The unit is the target generated power: kJ/h; x is the number of₇The unit of the maximum sludge mixed combustion amount is as follows: kg/h; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The unit is the lower heating value of the sludge and is as follows: kJ/kg.

Further, the total fuel amount a is the sum of the coal amount and the sludge amount.

The invention also adopts another technical scheme that: a system for calculating the maximum sludge co-combustion amount of a coal-fired boiler comprises:

the system comprises a parameter acquisition unit, a data processing unit and a data processing unit, wherein the parameter acquisition unit is used for acquiring related parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under typical load;

the first target maximum sludge mixed combustion amount calculating unit calculates a first target maximum sludge mixed combustion amount according to the lowest hearth temperature bearing value of the coal-fired boiler under the typical load;

the second target maximum sludge mixed combustion amount calculating unit calculates a second target maximum sludge mixed combustion amount according to the maximum fuel amount bearing value of the coal mill under the typical load;

the third target maximum sludge co-combustion amount calculating unit calculates a third target maximum sludge co-combustion amount according to the maximum NO bearing value of the denitration system under the typical load;

a fourth target maximum sludge mixed combustion amount calculation unit for calculating the SO of the desulfurization system under the typical load₂Calculating the fourth target maximum sludge blending combustion amount according to the maximum bearing value;

the fifth target maximum sludge mixed combustion amount calculation unit calculates a fifth target maximum sludge mixed combustion amount according to the maximum dust bearing value of the dust removal system under the typical load;

the sixth target maximum sludge mixed combustion amount calculating unit calculates a sixth target maximum sludge mixed combustion amount according to the maximum dischargeable value of various heavy metals of the wastewater system under the typical load;

the maximum sludge blending combustion amount calculation unit is used for comparing the first target maximum blending combustion amount, the second target maximum blending combustion amount, the third target maximum blending combustion amount, the fourth target maximum blending combustion amount, the fifth target maximum blending combustion amount and the sixth target maximum blending combustion amount, and obtaining the target maximum sludge blending combustion amount by taking the minimum value; and correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

Further, in the sixth target maximum sludge co-combustion amount calculating unit, the respective sixth maximum sludge co-combustion amount is calculated according to the maximum dischargeable values of various heavy metals of the wastewater system, wherein the minimum value is the sixth target maximum sludge co-combustion amount.

According to the related parameters and sludge characteristics of the coal-fired boiler, the coal mill, the denitration system, the desulfurization system, the dedusting system and the wastewater system under the typical load, the sludge mixable combustion amount under the typical load is improved to the maximum extent on the premise of ensuring the power generation capacity of the coal-fired unit and the safe operation of the coal-fired boiler.

Drawings

FIG. 1 is a flowchart of a method for calculating the maximum sludge co-combustion amount of a coal-fired boiler according to embodiment 1 of the present invention;

FIG. 2 is a schematic diagram of a system for calculating the maximum sludge co-combustion amount of a coal-fired boiler according to embodiment 2 of the present invention.

Detailed Description

The following detailed description of the embodiments of the present invention is provided in connection with the accompanying drawings for the purpose of facilitating understanding and understanding of the technical solutions of the present invention. It is to be understood that the specific embodiments described herein are merely illustrative of some, but not all, embodiments of the invention and that other embodiments may be devised by those skilled in the art without the use of the inventive faculty and the scope of the invention is to be protected.

Example 1

Referring to the attached drawing 1, a flow chart of a method for calculating the maximum sludge co-combustion amount of a coal-fired boiler according to the present invention includes the following specific steps:

step 1, acquiring relevant parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under a typical load;

step 2, calculating a first target maximum sludge co-combustion amount of the lowest hearth temperature bearing value of the coal-fired boiler under a typical load;

step 3, calculating a second target maximum sludge blending combustion amount of the maximum fuel bearing value of the coal mill under the typical load;

step 4, calculating a third target maximum sludge co-combustion amount of the maximum NO bearing value of the denitration system under a typical load;

step 5, calculating the SO of the desulfurization system under the typical load₂The fourth target maximum sludge mixed combustion amount of the maximum bearing value;

step 6, calculating the fifth target maximum sludge co-combustion amount of the dust maximum bearing value of the dust removal system under the typical load;

step 7, respectively calculating the sludge co-combustion amount of the maximum dischargeable value of each heavy metal in the wastewater system under the typical load, wherein the minimum value is the sixth maximum target sludge co-combustion amount;

step 8, comparing the first target maximum blending combustion amount, the second target maximum blending combustion amount, the third target maximum blending combustion amount, the fourth target maximum blending combustion amount, the fifth target maximum blending combustion amount and the sixth target maximum blending combustion amount, and taking the minimum value as the target maximum sludge blending combustion amount of the coal-fired boiler under the typical load;

and 9, correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

The method can accurately calculate the sludge amount which can be mixed and burned in the coal-fired boiler according to the related parameters and the sludge characteristics of the coal-fired boiler, the coal mill, the denitration system, the desulfurization system, the dedusting system and the wastewater system under the typical load, namely, the sludge mixing and burning amount under the typical load is improved to the maximum extent on the premise of ensuring the power generation capacity of the coal-fired unit and the safe operation of the coal-fired boiler.

Specifically, the calculation formula of the first target maximum sludge co-combustion amount under the typical load is as follows:

wherein A is total fuel quantity, and the unit is as follows: kg/h; t is₁The lowest furnace temperature bearable value of the coal-fired boiler is represented by the unit: k; t is₂The hearth temperature during the combustion of the whole coal has the unit: k; t is₃The unit is the influence value of the sludge on the hearth temperature: K.

more specifically, the total fuel amount a is the sum of the coal amount and the sludge amount. For the typical load, in the calculation, the boiler efficiency is considered to be unchanged in the case of the small amount of sludge co-combustion, i.e., the total fuel amount a is considered to be unchanged. After the sludge is mixed and burnt, the hearth temperature is reduced, and the lowest hearth temperature T of the coal-fired boiler is generally considered₁The bearable value is controlled to be more than 1100K. Hearth temperature T during full coal combustion₂And the influence value T of sludge on the temperature of the hearth₃Can be obtained by a test method in advance.

Specifically, the second target maximum sludge co-combustion amount under a typical load is calculated according to the following two formulas:

wherein Q is₁The heat release required by the hearth is as follows: kJ/h; b is the maximum grinding amount of a single coal mill, and the unit is as follows: kg/h; n is the number of coal mills in operation; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The unit is the lower heating value of the sludge and is as follows: kJ/kg; f is the primary air volume of a single coal mill, and the unit is as follows: kg/h; c is the air specific heat, and the unit is: kJ/(kg. K); t is t₁The unit is the primary air temperature at the inlet of the coal mill: k; t is t₂The lowest allowable primary air temperature of the outlet of the coal mill is represented by the following unit: k; γ is the latent heat of vaporization of water in units of: kJ/kg; w is a₁Water content outside coal,%; w is a₂Is the external water content of the sludge.

More specifically, in the two formulas, the assumed conditions are that the coal amount of each operating coal mill is the same, the sludge amount of each operating coal mill is the same, and the second target maximum sludge co-combustion amount is the smaller value of the calculation results of the two formulas.

More specifically, for a typical load, the required furnace heat release Q₁Keeping constant, coal low calorific value q₂And the lower heating value q of the sludge₃Can be obtained by detection, and in order to prevent coal blockage of the pulverized coal pipe, the lowest allowable primary air temperature t of the outlet of the coal mill₂The temperature is controlled to be above 330K.

Specifically, the calculation formula of the third target maximum sludge co-combustion amount under the typical load is as follows:

wherein N is₁The maximum NO bearing value of the denitration system is expressed by the following unit: kg/h; a is the total fuel quantity, with the unit: kg/h; n is a radical of₂Generating NO coefficients for the coal; n is a radical of₃Generating NO coefficients for the sludge.

More specifically, the maximum NO tolerance value N of the denitration system₁Can be obtained by the design specification of a denitration system, and the NO coefficient N is generated by coal₂And the NO coefficient N generated by sludge₃Can be obtained by experimental methods.

Specifically, the calculation formula of the fourth target maximum sludge co-combustion amount under the typical load is as follows:

wherein S is₁For desulfurization system SO₂Maximum tolerated value, in units of: kg/h; a is the total fuel quantity, with the unit: kg/h; s₂Generating SO for coal₂A coefficient; s₃Generating SO for sludge₂And (4) the coefficient.

More specifically, the desulfurization system SO₂Maximum value of S₁Can be obtained by the design specification of a desulfurization system, and the coal generates SO₂Coefficient S₂Generating SO from sludge₂Coefficient S₃Can be obtained by experimental methods.

Specifically, the calculation formula of the fifth target maximum sludge co-combustion amount under the typical load is as follows:

wherein, V₁The unit is the maximum bearing value of dust of a dust removal system: kg/h; a is the total fuel quantity, with the unit: kg/h; v₂Ash content in coal,%; v₃Is the ash content in the sludge.

More specifically, the dust maximum value V of the dust removal system₁Can be obtained through the design specification of a dust removal system, and the coefficient V of the generated dust of the coal₂Sludge-to-dust coefficient V₃Can be obtained by experimental methods.

Specifically, the calculation formula of the sixth maximum sludge co-combustion amount under the typical load is as follows:

wherein M is₁The maximum dischargeable value of various heavy metals in a wastewater system is as follows: kg/h; a is the total fuel quantity, with the unit: kg/h; m₂The mass fraction of various heavy metals in the coal is percent; m₃Is the mass fraction of various heavy metals in the sludge.

More specifically, the respective x is calculated according to the maximum dischargeable value of each heavy metal in the wastewater system₆And the minimum value is the sixth target maximum sludge co-combustion amount.

Specifically, the real-time correction formula of the maximum sludge blending combustion amount of the coal-fired boiler under the typical load is as follows:

wherein D is₁The unit is the actual generated power: kJ/h; d₂The unit is the target generated power: kJ/h; x is the number of₇The unit of the maximum sludge mixed combustion amount is as follows: kg/h.

More specifically, because the low-level power generation amount of the sludge is smaller than the low-level heating amount of the coal, the actual power generation power of the coal-fired unit may not reach the target power generation power after the sludge is mixed with the sludge, and at the moment, the target maximum sludge mixed combustion amount is corrected in real time according to the actual power generation power and the target power generation power of the coal-fired unit, so that the actual power generation power reaches the target power generation power.

Example 2

Referring to fig. 2, the present embodiment provides a system for calculating a maximum sludge blending combustion amount of a coal-fired boiler, including:

the parameter acquisition unit is used for acquiring relevant parameters of a coal-fired boiler, a coal mill, a denitration system, a desulfurization system, a dust removal system and a wastewater system under typical load;

the first target maximum sludge mixed combustion amount calculating unit calculates a first target maximum sludge mixed combustion amount according to the lowest hearth temperature bearing value of the coal-fired boiler under the typical load;

the second target maximum sludge mixed combustion amount calculating unit calculates a second target maximum sludge mixed combustion amount according to the maximum fuel amount bearing value of the coal mill under the typical load;

the third target maximum sludge co-combustion amount calculating unit calculates a third target maximum sludge co-combustion amount according to the maximum NO bearing value of the denitration system under the typical load;

a fourth target maximum sludge mixed combustion amount calculation unit for calculating the SO of the desulfurization system under the typical load₂Calculating the fourth target maximum sludge blending combustion amount according to the maximum bearing value;

the fifth target maximum sludge mixed combustion amount calculation unit calculates a fifth target maximum sludge mixed combustion amount according to the maximum dust bearing value of the dust removal system under the typical load;

the sixth target maximum sludge mixed combustion amount calculation unit calculates the sixth target maximum sludge mixed combustion amount according to the maximum dischargeable value of various heavy metals of the wastewater system under the typical load;

the maximum sludge mixed combustion amount calculating unit is used for comparing the first target maximum sludge mixed combustion amount, the second target maximum sludge mixed combustion amount, the third target maximum sludge mixed combustion amount, the fourth target maximum sludge mixed combustion amount, the fifth target maximum sludge mixed combustion amount and the sixth target maximum sludge mixed combustion amount, and taking the minimum value as the target maximum sludge mixed combustion amount of the coal-fired boiler under the typical load; and correcting the target maximum sludge co-combustion amount in real time according to the target power generation power and the actual power generation power of the coal-fired unit to obtain the maximum sludge co-combustion amount of the coal-fired boiler.

In the first target maximum sludge co-combustion amount calculation unit, a calculation formula of the first target maximum sludge co-combustion amount under a typical load is as follows:

wherein A is the total fuel quantity, and the unit is: kg/h; t is₁The lowest furnace temperature bearable value of the coal-fired boiler is represented by the unit: k; t is₂The hearth temperature during the combustion of the whole coal has the unit: k; t is₃The unit is the influence value of the sludge on the hearth temperature: K.

in the second target maximum sludge co-combustion amount calculation unit, the second target maximum sludge co-combustion amount under the typical load is calculated according to the following two formulas:

in the formula, Q₁The heat release required by the hearth is as follows: kJ/h; b is the maximum grinding amount of a single coal mill, and the unit is as follows: kg/h; n is the number of coal mills in operation; q. q.s₂The unit is the coal low calorific value: kJ/kg; q. q.s₃The lower calorific value of the sludge is expressed in unit of: kJ/kg; f is the primary air volume of a single coal mill, and the unit is as follows: kg/h; c is the air specific heat, and the unit is: kJ/(kg. K); t is t₁The unit is the primary air temperature at the inlet of the coal mill: k; t is t₂The lowest allowable primary air temperature of the outlet of the coal mill is represented by the following unit: k; γ is the latent heat of vaporization of water in units of: kJ/kg; w is a₁Water content outside coal,%; w is a₂Is the external water content of the sludge,%;

and measuring the second target maximum sludge mixed combustion amount to obtain the smaller value of the calculation results of the two formulas.

In the third target maximum sludge co-combustion amount calculation unit, a calculation formula of the third target maximum sludge co-combustion amount under a typical load is as follows:

in the formula, N₁The maximum NO bearing value of the denitration system is expressed by the following unit: kg/h; a is the total fuel quantity, with the unit: kg/h; n is a radical of₂Generating NO coefficients for the coal; n is a radical of₃Generating NO coefficients for the sludge.

In the fourth target maximum sludge co-combustion amount calculation unit, a calculation formula of the fourth target maximum sludge co-combustion amount under a typical load is as follows:

in the formula, S₁For desulfurization system SO₂Maximum tolerated value, in units of: kg/h; a is the total fuel quantity, with the unit: kg/h; s₂Generating SO for coal₂A coefficient; s₃Generating SO for sludge₂And (4) the coefficient.

In the fifth target maximum sludge co-combustion amount calculation unit, a calculation formula of the fifth target maximum sludge co-combustion amount under a typical load is as follows:

in the formula, V₁The unit is the maximum bearing value of dust of a dust removal system: kg/h; a is the total fuel quantity, with the unit: kg/h; v₂Ash content in coal,%; v₃Is the ash content in the sludge.

In the sixth target maximum sludge co-combustion amount calculation unit, a calculation formula of the sixth maximum sludge co-combustion amount under a typical load is as follows:

in the formula, M₁The maximum dischargeable value of various heavy metals in a wastewater system is as follows: kg/h; a is the total fuel quantity, with the unit: kg/h; m₂The mass fraction of various heavy metals in the coal is percent; m₃The mass fraction of each heavy metal in the sludge is percent;

respectively calculating respective x according to the maximum dischargeable value of various heavy metals in the wastewater system₆And the minimum value is the sixth target maximum sludge co-combustion amount.

In the maximum sludge mixed combustion amount calculation unit, the real-time correction formula of the maximum sludge mixed combustion amount of the coal-fired boiler under the typical load is as follows:

in the formula, D₁The unit is the actual generated power: kJ/h; d₂The unit is the target generated power: kJ/h; x is the number of₇The unit of the maximum sludge mixed combustion amount is as follows: kg/h.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.