CN112069443B - Coal pressure reduction calculation method and system for heat supply substitution of cogeneration unit - Google Patents

Abstract

The invention provides a coal pressure decrement calculation method and a system for heat supply substitution of a cogeneration unit, which take the balance of total heat and total electric quantity of a whole area as preconditions, divide the coal consumption of the cogeneration unit into heat supply coal consumption and power generation coal consumption, respectively calculate the heat supply and power generation coal consumption of the large-scale and small-scale cogeneration unit, further calculate the total coal pressure decrement after the heat supply substitution of the whole area, and have simple operation and accurate calculation result.

Description

Coal-fired pressure reduction calculation method and system for heat supply substitution of cogeneration units

Technical field

The present disclosure belongs to the field of energy calculation technology, and specifically relates to a coal-fired pressure reduction calculation method and system for heat supply replacement of a combined heat and power unit.

Background technique

The statements in this section merely provide background technical information related to the present disclosure and do not necessarily constitute prior art.

Coal consumption for heating in winter accounts for a very large proportion of total coal consumption, and coal is the main energy used for heating in some areas.

According to the inventor's understanding, urban central heating currently mainly uses several heating methods such as large-scale combined heat and power units (generally above 200MW), small-scale combined heat and power units (generally below 50MW), small coal-fired boilers, etc. Small coal-fired boilers Boilers and small cogeneration units are inefficient, while large cogeneration units have high thermal efficiency. Using high-efficiency cogeneration units to replace inefficient small coal-fired boilers and small cogeneration units for heat supply is an important way to achieve coal reduction. However, at this stage, no accurate calculation method has been proposed for the reduction of coal combustion after using large-scale cogeneration units to replace small-scale cogeneration units for heat supply, and it is impossible to scientifically evaluate the effect of coal reduction for the whole society after the replacement of heat supply.

Contents of the invention

In order to solve the above problems, this disclosure proposes a method and system for calculating coal-fired reduction reduction for heat supply substitution of cogeneration units. This disclosure helps the government energy department to formulate annual coal-fired reduction indicators, determine the heating replacement area, etc. Data support provided.

According to some embodiments, the present disclosure adopts the following technical solutions:

A method for calculating coal-fired pressure reduction for heat supply substitution in cogeneration units, including the following steps:

Based on the heating area where large cogeneration units are used to replace small cogeneration units within the set time period, calculate the heat supply required for substitution within the set time period;

Based on the boiler efficiency and pipeline efficiency of different cogeneration units, the heating coal consumption of large and small cogeneration units is calculated respectively;

Based on the obtained heat supply and the heating coal consumption of large and small cogeneration units, calculate the heating coal consumption required by large and small cogeneration units when the heat supply within the set time period is met;

Based on the principle of equivalent enthalpy drop, the heat to electricity ratio of large and small cogeneration units is calculated respectively. Based on the obtained heat supply and the heat to electricity ratio of large/small cogeneration units, the factors of large and small cogeneration units are calculated respectively. The amount of electricity generated by heating is calculated by calculating the coal consumption of large and small combined heat and power units in the set time period;

Based on the coal consumption for power generation of large and small cogeneration units, calculate the corresponding reduction in power generation of large cogeneration units in pure condensing conditions during non-heating seasons due to substitution, and calculate the reduced coal consumption due to less power generation in pure condensing conditions;

Based on the heat supply coal consumption required by large and small cogeneration units to meet the heat supply within the set time period, the coal consumption for power generation by large and small cogeneration units, and the pure condensation condition with less power generation. The reduced coal consumption is calculated to obtain the reduction in coal burning after heating replacement.

As an optional implementation, based on the boiler efficiency and pipeline efficiency of different cogeneration units, the specific process of calculating the heating coal consumption of large and small cogeneration units includes:

According to the heating area where large-scale cogeneration units are used to replace small-scale cogeneration units within the set time period, the heat supply required for heating replacement within the set time period is calculated;

According to the boiler efficiency and pipeline efficiency of different types of combined heat and power units, calculate the heating coal consumption of the corresponding type of combined heat and power units;

According to the heat supply required for heating replacement within the set time period and the heating coal consumption of different types of cogeneration units, calculate the heat supply required for the corresponding type of cogeneration unit to meet the heat supply within the set time period. Heat consumption of coal.

As an optional implementation, based on the area where large-scale cogeneration units are used to replace small-scale cogeneration units for heat supply within a set time period, the specific process of calculating the heat supply required for substitution within a set time period is:

The heat supply required in the set time period is equal to the heating area planned to be replaced by a small cogeneration unit by a large cogeneration unit in the set time period, the building heating area index, and the average heating season heating time. product.

As an optional implementation method, based on the boiler efficiency and pipeline efficiency of different cogeneration units, the heating coal consumption of large and small cogeneration units is calculated respectively. The specific process includes:

The heating coal consumption of a large-scale combined heat and power unit is proportional to the reciprocal of the product of the large-scale combined heat and power unit's boiler efficiency and boiler pipe efficiency;

The heating coal consumption of a small cogeneration unit is proportional to the reciprocal of the product of the boiler efficiency of the small cogeneration unit and the boiler pipe efficiency.

As an optional implementation, the specific process of calculating the coal consumption for power generation of large and small cogeneration units within a set time period includes:

Calculate the proportion of large and small cogeneration units used for heating and power generation based on the equivalent enthalpy drop principle;

Using the required heat supply in the set time period and the heat-to-power ratio of the corresponding type of cogeneration unit, calculate the power generation generated by each type of cogeneration unit due to heat supply, and calculate the power generation by the corresponding type of cogeneration unit due to heat supply in the set time period. The amount of coal consumed for power generation.

As an optional implementation method, based on the coal consumption of large-scale and small-scale cogeneration units for power generation, it is calculated that due to substitution, large-scale cogeneration units will correspondingly reduce the power generation of pure condensing conditions during the non-heating season, and calculate that the power generation of pure condensing conditions will be less. The specific process of reducing coal consumption includes: the large-scale combined heat and power unit correspondingly reduces the power generation in pure condensation conditions during the non-heating season, which is the power generation generated by the large-scale combined heat and power unit due to heating minus the small-scale combined heat and power unit. The amount of power generated due to heating; the reduced coal consumption due to less power generation in pure condensing conditions is the corresponding reduction in power generation in pure condensing conditions of large-scale cogeneration units in the non-heating season and the corresponding reduction in power generation in pure condensing conditions of large-scale cogeneration units in pure condensing conditions The product of coal consumption rate for power generation.

As an optional implementation method, based on the heating coal consumption required by large and small cogeneration units, the power generation coal consumption of large and small cogeneration units, and The specific process of calculating the coal pressure reduction after heat supply substitution includes the reduction of coal consumption due to less power generation in pure condensation conditions: the coal pressure reduction after heat supply substitution is: Small cogeneration unit equipment The sum of coal consumption for heating and power generation within a certain period of time is subtracted from the sum of coal consumption for heating and power generation of large-scale combined heat and power units within a set period of time, plus the small amount of power generated under pure condensation working conditions of large-scale combined heat and power units. And reduced coal consumption.

A coal-fired pressure reduction calculation system that replaces the heat supply of cogeneration units, including:

A unit used to calculate the heat supply required for replacement within a set time period based on the area where a large cogeneration unit is used to replace a small cogeneration unit for heating within a set time period;

A unit used to calculate the heating coal consumption of large and small cogeneration units based on different boiler efficiencies and pipeline efficiencies of different cogeneration units;

Used to calculate the heating coal consumption required by large and small cogeneration units when the heat supply within a set time period is met based on the obtained heat supply and the heating coal consumption of large and small cogeneration units. unit of quantity;

Used to calculate the heat to electricity ratio of large and small cogeneration units based on the equivalent enthalpy drop principle. Based on the obtained heat supply and the heat to electricity ratio of large/small cogeneration units, calculate large and small cogeneration units respectively. The unit generates electricity due to heat supply, and is a unit that calculates the coal consumption for power generation of large and small cogeneration units within a set time period;

It is used to calculate the coal consumption of power generation based on large and small cogeneration units. It calculates the corresponding reduction in power generation of large cogeneration units in pure condensing conditions during non-heating seasons due to substitution. It also calculates the reduced coal consumption due to less power generation in pure condensing conditions. unit of quantity;

It is used to calculate the coal consumption for heating required by large and small cogeneration units, the coal consumption for power generation of large and small cogeneration units, and the pure condensation operating conditions based on the amount of heat supply required within a set time period. The reduction in coal consumption due to power generation is calculated as the unit of reduction in coal consumption after heating replacement.

A computer-readable storage medium stores a plurality of instructions, and the instructions are suitable for being loaded and executed by a processor of a terminal device by the coal-fired pressure reduction calculation method for heat supply substitution of a cogeneration unit.

A terminal device includes a processor and a computer-readable storage medium. The processor is used to implement each instruction; the computer-readable storage medium is used to store a plurality of instructions. The instructions are suitable for being loaded and executed by the processor. Calculation method for coal-fired pressure reduction for heat supply substitution of cogeneration units.

Compared with the existing technology, the beneficial effects of the present disclosure are:

This embodiment provides a calculation method for the coal pressure reduction in the entire area after a large-scale cogeneration unit replaces a small-scale cogeneration unit for heat supply. This method provides This paper provides a method for calculating coal-fired reduction in the entire region after heat supply replacement. The calculation process is simple and easy to operate, and the calculation results are relatively accurate. It provides data support for formulating annual coal-fired reduction indicators and determining the heat supply replacement area.

Detailed ways:

The present disclosure will be further described below with reference to examples.

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It should be noted that the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the exemplary embodiments according to the present disclosure. As used herein, the singular forms are also intended to include the plural forms unless the context clearly indicates otherwise. Furthermore, it will be understood that when the terms "comprises" and/or "includes" are used in this specification, they indicate There are features, steps, operations, means, components and/or combinations thereof.

In this embodiment, the whole year is used as the set time period. Of course, in other embodiments, other area sizes and time period lengths may be specified.

A method for calculating coal-fired pressure reduction when a large cogeneration unit replaces a small cogeneration unit for heat supply, including the following steps:

Step 1: Calculate the heat supply Q required for annual heating replacement based on the annual heating area S where large-scale cogeneration units are used to replace small-scale cogeneration units;

Step 2: Calculate the heating coal consumption b _drdgr of the large-scale combined heat and power unit based on the boiler efficiency eta _drdg and pipeline efficiency eta _drdgd of the large-scale combined heat and power unit;

Step 3: Based on the heat supply Q required for annual heat supply replacement calculated in step 1 and the heating coal consumption b _drdgr of large-scale combined heat and power units calculated in step 2, calculate the large-scale combined heat and power unit that meets the annual heat supply Required coal consumption B _drdgr ;

Step 4: Calculate the heating coal consumption b _xrdgr of the small combined heat and power unit based on the boiler efficiency eta _xrdg and pipeline efficiency eta _xrdgd of the small combined heat and power unit;

Step 5: Based on the heat supply Q required for annual heating replacement calculated in step 1 and the heating coal consumption _b Required coal consumption B _xrdgr ;

Step 6: Before the heat supply steam from the combined heat and power unit is extracted, it first performs work in the steam turbine to generate electricity, and then is extracted for external heating. Therefore, the combined heat and power unit will generate electricity when supplying heat. According to the equivalent enthalpy drop principle, calculate the large and The proportion of small cogeneration units used for heating and power generation (referred to as heat to power ratio), and/>

Step 7: Use the annual required heat supply Q calculated in step 1 and step 6 to calculate the heat to electricity ratio of the large-scale combined heat and power unit, and calculate the power generation D _drd generated by the large-scale combined heat and power unit due to heat supply;

Step 8: Based on the power generation D _drd generated by the large-scale combined heat and power unit calculated in step 7, calculate the annual coal consumption B _drdfd generated by the large-scale combined heat and power unit due to heat supply and power generation;

Step 9: Use the annual required heat supply Q calculated in step 1 and step 6 to calculate the heat to electricity ratio of the small cogeneration unit, and calculate the power generation D _xrd generated by the small cogeneration unit due to heat supply;

Step 10: Based on the power generation D _xrd generated by the small-scale combined heat and power unit calculated in step 9, calculate the annual coal consumption B _xrdfd generated by the small-scale combined heat and power unit due to heat supply and power generation;

Step 11: When the heat supply is the same, the power generation D _drd generated by the large-scale cogeneration unit is greater than the power generation D _xrd of the small cogeneration unit. Therefore, the total power generation in the whole region's heating season increases after the heat supply substitution. The increased amount is D _drd -D _xrd . In order to keep the total annual power generation in the entire region unchanged, the power generation of large-scale combined heat and power units in the non-heating season is correspondingly reduced by D _drd -D _xrd in the pure condensing condition. Calculate that the pure condensing condition is less Reduced coal consumption B _drdjs due to power generation;

Step 12: Calculate the coal consumption reduced in the entire region after using large-scale cogeneration units to replace small-scale cogeneration units for heating, which is equal to the coal consumption generated by small-scale cogeneration units for annual heating and power generation. B _xrdgr and B _xrdfd minus the coal consumption B _drdgr and B _drdfd generated by the annual heating and power generation of large-scale combined heat and power units, plus the reduction of pure condensing power generation savings of large-scale combined heat and power units in the non-heating season. The coal burning amount B _drdjs .

In step 1, the calculation of the heat supply Q required for the whole year is as follows:

Q＝S×q×t×3600/10 ⁹

In the formula: Q is the heat supply required throughout the year, GJ; S is the heating area planned to use large-scale cogeneration units to replace small-scale cogeneration units, m ² ; q building heating area index, W/ m ² ; t is the number of heating hours throughout the heating season, h, which is taken as 2880 in this embodiment;

In step 2, the calculation formula for heating coal consumption of large-scale combined heat and power units is as follows:

In the formula: b _drdgr - heating coal consumption of large-scale combined heat and power unit, kg/GJ; η _drdg - boiler efficiency of large-scale combined heat and power unit, %, taken as 0.92 in this embodiment; η _drdgd - boiler pipe of large-scale combined heat and power unit Efficiency, %, is taken as 0.99 in this embodiment.

In step 3 described above, the calculation formula for the coal consumption required for annual heating by large-scale combined heat and power units is as follows:

B _drdgr ＝Q×b _drdgr /10 ⁷

In the formula: B _drdgr - the coal consumption required for annual heating of large-scale combined heat and power units, 10,000 tons;

In step 4, the calculation formula for the heating coal consumption of the small cogeneration unit is as follows:

In the formula: b _xrdgr - heating coal consumption of small cogeneration unit, kg/GJ; eta _xrdg - boiler efficiency of small cogeneration unit, %, taken as 0.85 in this embodiment; eta _xrdgd - boiler pipe of small cogeneration unit The efficiency, %, is taken as 0.97 in this embodiment.

In the step 5 mentioned above, the calculation formula for the coal consumption required by the small cogeneration unit for heating throughout the year is as follows:

_Bxrdgr ＝Q× _bxrdgr /10 ⁷

In the formula: B _xrdgr - the coal consumption required for annual heating of small thermal power units, 10,000 tons;

In step 6, the calculation formula for the proportion of heat supply and power generation in the heat supply and extraction part of large and small thermal power units is as follows:

In the formula: is the ratio of heat supply and power generation in the heating and extraction part of the large-scale combined heat and power unit, h _drdcq is the extraction steam enthalpy of the large-scale combined heat and power unit, kJ/kg; h _drds is the extraction steam hydrophobic enthalpy of the large-scale combined heat and power unit, kJ /kg; h _drdzq is the main steam enthalpy of small thermal power units, kJ/kg; h _drdhrh is the reheat enthalpy of large cogeneration units, kJ/kg; h _drdcrh is the cold reheat enthalpy of large cogeneration units, kJ/kg;

is the ratio of heat supply and power generation in the heating and extraction part of the small combined heat and power unit, h _xrdcq is the extraction steam enthalpy of the small thermal power unit, kJ/kg; h _xrds is the extraction steam hydrophobic enthalpy of the small thermal power unit, kJ/kg; h _xrdzq is the main steam enthalpy of small thermal power unit, kJ/kg;

In step 7 described above, the calculation formula for the annual power generation D _drd of the heat supply and steam extraction part of the large-scale combined heat and power unit is as follows:

In the formula: D _drd is the power generation capacity of the large-scale combined heat and power unit's heating season heating extraction part, 10,000 kwh;

In step 8 described above, the coal consumption B _drdfd generated by large-scale combined heat and power units for heating and power generation throughout the year is calculated as follows:

B _drdfd ＝D _drd ×3.6/Q _net.ar /η _drdg /η _drdgd

In the formula: B _drdfd is the coal consumption of large-scale combined heat and power units for heating and power generation throughout the year, 10,000 tons; Q _net,ar is the calorific value of standard coal, kJ/kg, which is taken as 29307 in this embodiment .

In step 9, the annual power generation D _xrd of the heat and steam extraction part of the small cogeneration unit is calculated as follows:

In the formula: _D

In step 10, the coal consumption B _xrdfd of the small cogeneration unit for heating and power generation throughout the year is calculated as follows:

B _xrdfd =D _xrd ×3.6/Q _net.ar /η _xrdg /η _xrdgd

In the formula: B _xrdfd is the annual coal consumption of small cogeneration units for heating and power generation, 10,000 tons; Q _net,ar is the calorific value of standard coal, kJ/kg, which is taken as 29307 in this embodiment.

In the step 11 described above, the calculation formula for the coal consumption saved by large-scale cogeneration units with less power generation and pure condensation operation during the non-heating season is as follows:

B _drdjs = (D _drd -D _xrd ) × η _drdfd /10 ⁶

In the formula: B _drdjs The coal consumption saved by less power generation of large-scale combined heat and power units in pure condensing conditions in non-heating seasons, 10,000 tons; η _drdfd is the coal consumption rate of large-scale combined heat and power units in pure condensing conditions, g/kW.h.

In the step 11 described above, the calculation formula for the annual coal-fired reduction after heating replacement is as follows:

B _yj ＝B _xrdgr -B _drdgr +B _xrdfd -B _drdfd +B _drdjs

In the formula: B _yj - the amount of coal burned in the whole year after replacing small-scale cogeneration for heat supply with large cogeneration units, 10,000 tons;

When the heating area required for heat supply replacement is known, this embodiment can be used to calculate the coal burning amount reduced throughout the year after heat supply replacement; similarly, when the annual coal burning amount reduction index is known, this embodiment can be used to calculate In this embodiment, it is possible to reversely deduce how much heating replacement of the heating area needs to be completed to achieve the above indicators.

The following product examples are also provided:

A coal-fired pressure reduction calculation system that replaces the heat supply of cogeneration units, including:

A unit used to calculate the heat supply required for replacement within a set time period based on the area where a large cogeneration unit is used to replace a small cogeneration unit for heating within a set time period;

A unit used to calculate the heating coal consumption of large and small cogeneration units based on different boiler efficiencies and pipeline efficiencies of different cogeneration units;

Used to calculate the heating coal consumption required by large and small cogeneration units when the heat supply within a set time period is met based on the obtained heat supply and the heating coal consumption of large and small cogeneration units. unit of quantity;

Used to calculate the heat to electricity ratio of large and small cogeneration units based on the equivalent enthalpy drop principle. Based on the obtained heat supply and the heat to electricity ratio of large/small cogeneration units, calculate large and small cogeneration units respectively. The unit generates electricity due to heat supply, and is a unit that calculates the coal consumption for power generation of large and small cogeneration units within a set time period;

It is used to calculate the coal consumption of power generation based on large and small cogeneration units. It calculates the corresponding reduction in power generation of large cogeneration units in pure condensing conditions during non-heating seasons due to substitution. It also calculates the reduced coal consumption due to less power generation in pure condensing conditions. unit of quantity;

It is used to calculate the coal consumption for heating required by large and small cogeneration units, the coal consumption for power generation of large and small cogeneration units, and the pure condensation operating conditions based on the amount of heat supply required within a set time period. The reduction in coal consumption due to power generation is calculated as the unit of reduction in coal consumption after heating replacement.

A computer-readable storage medium in which a plurality of instructions are stored. The instructions are suitable for being loaded and executed by a processor of a terminal device. A method of replacing small-scale combined heat and power units with heating provided by the embodiments. Calculation method for coal-fired pressure reduction.

A terminal device includes a processor and a computer-readable storage medium. The processor is used to implement each instruction; the computer-readable storage medium is used to store multiple instructions. The instructions are suitable for the processor to load and execute an instruction provided by the embodiment. A method for calculating coal-fired pressure reduction when large-scale combined heat and power units replace small-scale combined heat and power units for heat supply.

Those skilled in the art will appreciate that embodiments of the present disclosure may be provided as methods, systems, or computer program products. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements one process or multiple processes within a process.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing a process or processes within a process.

The above descriptions are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this disclosure shall be included in the protection scope of this disclosure.

Although the specific embodiments of the present disclosure have been described above, they do not limit the scope of protection of the present disclosure. Those skilled in the art should understand that based on the technical solutions of the present disclosure, those skilled in the art can do so without having to exert creative efforts. Various modifications or variations are still within the protection scope of the present disclosure.

Claims (10)

1. A coal pressure reduction calculation method for heat supply substitution of a cogeneration unit is characterized by comprising the following steps of:

calculating the heat supply quantity required by replacement in the set time period based on the heat supply area of the large-scale cogeneration unit instead of the small-scale cogeneration unit in the set time period;

based on the boiler efficiency and the pipeline efficiency of different cogeneration units, the heat supply coal consumption of the large-scale cogeneration units and the small-scale cogeneration units are calculated respectively;

calculating the heat supply consumption of the large-scale and small-scale cogeneration units when the heat supply quantity within a set time period is met based on the obtained heat supply quantity and the heat supply coal consumption of the large-scale and small-scale cogeneration units;

based on the equivalent enthalpy drop principle, respectively calculating the thermoelectric ratio of the large-scale and small-scale cogeneration units, respectively calculating the generated energy of the large-scale and small-scale cogeneration units due to heat supply based on the obtained heat supply and the thermoelectric ratio of the large-scale/small-scale cogeneration units, and calculating the power generation coal consumption of the large-scale and small-scale cogeneration units within a set time period;

based on the power generation and coal consumption of the large-scale and small-scale cogeneration units, the power generation amount under the pure condensation working condition is correspondingly reduced due to substitution in non-heating seasons of the large-scale cogeneration units, and the coal consumption reduced due to less power generation under the pure condensation working condition is calculated;

and calculating the coal pressure reduction after heat supply substitution based on the heat supply and coal consumption required by the large-scale and small-scale cogeneration units when the heat supply quantity in the set time period is satisfied and the power generation and coal consumption of the large-scale and small-scale cogeneration units and the coal consumption reduced by less power generation under the pure condensation condition.

2. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: based on the boiler efficiency and the pipeline efficiency of different cogeneration units, the specific process for respectively calculating the heat supply coal consumption of the large-scale cogeneration units and the small-scale cogeneration units comprises the following steps:

according to the heating area of the large-scale cogeneration unit for replacing the small-scale cogeneration unit in the set time period, calculating the heating quantity required by the replacement of heating in the set time period;

according to the boiler efficiency and the pipeline efficiency of the cogeneration units of different types, calculating the heat supply coal consumption of the cogeneration units of corresponding types;

and calculating the heat supply quantity required by the corresponding type of cogeneration units when the heat supply quantity meeting the set time period is calculated according to the heat supply quantity required by heat supply replacement in the set time period and the heat supply coal consumption of the different type of cogeneration units.

3. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: based on the heat supply area of the large-scale cogeneration unit for replacing the small-scale cogeneration unit in the set time period, the specific process for calculating the heat supply amount required by replacement in the set time period is as follows:

the heat supply amount required by the set time period is equal to the product of the heat supply area of the large-scale cogeneration unit for replacing the heat supply of the small-scale cogeneration unit, the heat supply area index of the building and the heat supply time of the average heating season.

4. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: based on the boiler efficiency and the pipeline efficiency of different cogeneration units, the heat supply coal consumption of the large-scale cogeneration units and the small-scale cogeneration units are respectively calculated, and the specific process comprises the following steps:

the heat supply coal consumption of the large-scale cogeneration unit is in proportional relation with the reciprocal of the product of the boiler efficiency and the boiler pipeline efficiency of the large-scale cogeneration unit;

the heating coal consumption of the small-sized cogeneration unit is in proportion to the reciprocal of the product of the boiler efficiency and the boiler pipeline efficiency of the small-sized cogeneration unit.

5. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: the specific process for calculating the power generation coal consumption of the large-scale and small-scale cogeneration units in the set time period comprises the following steps:

calculating the proportion of the large-scale and small-scale cogeneration units for heat supply and power generation according to the equivalent enthalpy drop principle;

and calculating the generated energy of each type of cogeneration unit due to heat supply by utilizing the required heat supply amount in the set time period and the thermoelectric ratio of the corresponding type of cogeneration unit, and calculating the generated energy consumption of the corresponding type of cogeneration unit due to heat supply and power generation in the set time period.

6. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: based on the power generation and coal consumption of the large-scale and small-scale cogeneration units, the method for calculating the power generation amount of the pure condensation working condition correspondingly reduces due to substitution in non-heating seasons of the large-scale cogeneration units, and the specific process for calculating the coal consumption reduced due to the fact that the pure condensation working condition is less in power generation comprises the following steps: the generated energy of the large-scale cogeneration unit due to heat supply is subtracted from the generated energy of the small-scale cogeneration unit due to heat supply by correspondingly reducing the generated energy of the pure condensation working condition in non-heat supply season of the large-scale cogeneration unit;

the consumption of the coal which is reduced by the small power generation under the pure condensation working condition is the product of the generated energy under the pure condensation working condition of the large-scale cogeneration unit and the generated coal consumption rate under the pure condensation working condition of the large-scale cogeneration unit, which is correspondingly reduced in the non-heating season of the large-scale cogeneration unit.

7. The method for calculating the coal pressure reduction of the heat supply substitute of the cogeneration unit according to claim 1, wherein the method comprises the following steps: based on the heat supply and coal consumption required by the large-scale and small-scale cogeneration units when the heat supply amount in a set time period is satisfied, the power generation and coal consumption of the large-scale and small-scale cogeneration units and the coal consumption reduced by less power generation under the pure condensation condition, the specific process for calculating the coal pressure reduction after heat supply substitution comprises the following steps: the coal pressure reduction after heat supply substitution is as follows: the sum of the heat supply and power generation coal consumption in the set time period of the small-sized cogeneration unit is subtracted, and the sum of the heat supply and power generation coal consumption in the set time period of the large-sized cogeneration unit is added, so that the power generation and the reduction coal consumption are reduced due to the fact that the pure condensation working condition of the large-sized cogeneration unit is less.

8. A coal-fired pressure reduction computing system for replacing heat supply of a cogeneration unit is characterized in that: comprising the following steps:

a unit for calculating the amount of heat supply required for replacement in the set time period based on the area of heat supply of the large cogeneration unit for replacing the small cogeneration unit in the set time period;

the unit is used for respectively calculating the heat supply coal consumption of the large-scale and small-scale cogeneration units based on the boiler efficiency and the pipeline efficiency of the different cogeneration units;

a unit for calculating the heating coal consumption required by the large and small cogeneration units when the heating amount within a set period is satisfied based on the obtained heating amount and the heating coal consumption of the large and small cogeneration units;

the unit is used for respectively calculating the thermoelectric ratio of the large-scale and small-scale cogeneration units based on the equivalent enthalpy drop principle, respectively calculating the generated energy of the large-scale and small-scale cogeneration units due to heat supply based on the obtained heat supply quantity and the thermoelectric ratio of the large-scale/small-scale cogeneration units, and calculating the power generation coal consumption of the large-scale and small-scale cogeneration units within a set time period;

the unit is used for calculating the coal consumption reduced by the fact that the electricity generation of the pure condensation working condition is correspondingly reduced due to substitution in non-heating seasons of the large-scale cogeneration unit based on the electricity generation coal consumption of the large-scale cogeneration unit and the small-scale cogeneration unit, and calculating the coal consumption reduced by the fact that the pure condensation working condition is less in electricity generation;

and the unit is used for calculating and obtaining the coal pressure reduction after heat supply substitution based on the heat supply and coal consumption required by the large-scale and small-scale cogeneration units when the heat supply quantity in the set time period is met, the power generation and coal consumption of the large-scale and small-scale cogeneration units and the coal consumption reduced by less power generation under the pure condensation condition.

9. A computer-readable storage medium, characterized by: in which instructions are stored which are adapted to be loaded by a processor of a terminal device and to carry out a method for calculating the reduction in the fire coal pressure for the heat supply substitution of a cogeneration unit according to any one of claims 1 to 7.

10. A terminal device, characterized by: comprising a processor and a computer-readable storage medium, the processor configured to implement instructions; a computer readable storage medium for storing a plurality of instructions adapted to be loaded by a processor and to perform a method of coal pressure reduction calculation for a cogeneration unit heat supply replacement according to any one of claims 1-7.