Method for controlling off-peak power generation through linkage of three gas holders

Abstract

The invention discloses a method for controlling off-peak power generation through linkage of three gas cabinets. A blast furnace gas cabinet, a first converter cabinet and a second converter cabinet operate in a grid-connected mode. In the electricity price valley period, the supply amount of blast furnace gas and converter gas is increased, the blast furnace gas usage amount of a gas generator set is reduced, outsourcing low-price electricity is increased, and meanwhile surplus blast furnace gas and converter gas are stored; and in the electricity price peak period, the supply amount of blast furnace gas and converter gas is reduced, the blast furnace gas usage amount of the gas generator set is increased, the external electricity purchase amount is increased, and the stored gas is increased and conveyed to the gas generator set for consumption so as to reduce the cabinet capacity. In the electricity price valley period and the electricity price peak period, coal gas is allocated through linkage among the blast furnace gas cabinet, the first converter cabinet, the second converter cabinet, the gas generator set and the production user, peak shifting power generation is achieved based on the change of the cabinet capacity, the electric energy time value is fully excavated, and the coal gas power generation benefit is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas-fired power generation, and in particular to a method for controlling peak-shifting power generation via linkage of three gas cabinets. Background Art

[0002] In the metallurgical industry, blast furnace gas is a combustible gas produced as a by-product of the blast furnace ironmaking process, and converter gas is a medium calorific value gas fuel within steel enterprises. Converter gas and blast furnace gas are not only required for ironmaking, steelmaking, and steel rolling production, but the remaining part can also be used for power generation in gas boilers of gas-fired generator sets of steel enterprises.

[0003] At present, due to the imbalance in the demand for power supply from the power grid during the day and at night, industrial electricity has basically adopted the peak-valley price supply method. Local governments will adjust the price difference according to the local power structure and power load. Generally, electricity consumption is concentrated during the day, and the demand for power supply from the power grid is large, which is the peak period, and the electricity price will be appropriately increased; while the demand is small at night, which is the valley period, and the electricity price will be appropriately lowered. In the steel industry, surplus gas resources are basically used for power generation. Therefore, under the background of time-of-use electricity prices, the gas resources of steel companies have different values ​​at different times.

[0004] It is reported that when existing production units increase production intensity, the consumption of converter gas increases, and the amount of by-product blast furnace gas also increases. The gas consumption required for production accounts for an equal proportion during peak, flat and valley electricity price periods, and the proportion of gas consumption during peak (peak) periods has not been effectively controlled. There is a large space for creating benefits through staggered gas use. For example, if only a single gas tank is used to allocate a single type of gas, it is impossible to reasonably allocate converter gas and blast furnace gas during valley electricity price periods and peak (peak) electricity price periods to achieve staggered power generation, fail to fully tap the time value of electricity, and fail to maximize the power generation efficiency. Summary of the invention

[0005] The purpose of the present invention is to provide a method for allocating gas through the linkage between gas tanks, and controlling peak-shifting power generation by linkage of three gas tanks based on the change of gas tank capacity to improve power generation efficiency, so as to solve the problem raised in the above background technology that steel enterprises have failed to fully tap the time value of electric energy and the power generation efficiency has not been maximized.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for controlling peak-shifting power generation by linkage of three gas cabinets.

[0008] The blast furnace gas holder, converter cabinet 1 and converter cabinet 2 are connected to the grid for operation, the outlet of the blast furnace gas holder is connected to the gas generator set and the first user, and the outlet of the converter cabinet 1 and converter cabinet 2 are connected to the gas generator set and the second user respectively;

[0009] During the electricity price valley period, the supply of blast furnace gas and converter gas is increased to increase production intensity, the use of blast furnace gas by gas-fired generators is reduced, and more low-priced electricity is purchased. At the same time, the surplus blast furnace gas is stored in the blast furnace gas tank to keep it in a high tank capacity state, and the surplus converter gas is transferred to converter tank 1 and converter tank 2 to keep it in a high tank capacity state;

[0010] During peak electricity price periods, reduce the supply of blast furnace gas and converter gas, increase the use of blast furnace gas by gas-fired generator sets, increase external electricity purchases to increase production intensity, and increase the gas stored in the blast furnace gas tank, converter tank one, and converter tank two to be transported to the gas-fired generator sets for consumption to reduce the tank capacity.

[0011] Preferably, the blast furnace gas tank is responsible for storing blast furnace gas and stabilizing the pressure, the converter tank 2 is responsible for storing and transporting the converter gas, and the converter tank 1 is used as a backup for regulating and distributing the converter gas.

[0012] Preferably, the operating range of the converter cabinet 1 and the converter cabinet 2 under normal production conditions is 15,000-65,000 m 3 .

[0013] Preferably, the control target of the cabinet capacity of the converter cabinet 2 when it is put into operation is 30,000-50,000 m 3 The converter cabinet is kept in standby state when it is out of operation. The converter gas storage capacity in standby state is 15,000 m 3 .

[0014] Preferably, there is a pressure difference between the converter cabinet 1 and the converter cabinet 2. During the electricity price valley period, when the cabinet capacity of the converter cabinet 2 is greater than 50,000 m 3 When the first outlet butterfly valve of converter cabinet 1 is opened, part of the converter gas of converter cabinet 2 is delivered to the gas power generation component through the compressor, and the remaining part is reversed to converter cabinet 1 through the first outlet butterfly valve. When the cabinet capacity of converter cabinet 1 reaches 65,000 m 3 Close the first outlet butterfly valve.

[0015] Preferably, during the peak electricity price period, when the capacity of converter cabinet 2 is less than 20,000 m 3 When the first outlet butterfly valve of converter cabinet 1 is opened, the second outlet butterfly valve of converter cabinet 2 is closed, converter cabinet 1 supplies converter gas to the gas generator set, and converter cabinet 2 recovers and stores the converter gas.

[0016] Preferably, during the peak electricity price period, the capacity of converter cabinet 1 is reduced to 20,000 m 3 , if the capacity of converter cabinet 1 is reduced and the capacity of converter cabinet 2 is increased to 50,000 m 3 , then suspend the capacity reduction operation of converter cabinet one, open the second outlet butterfly valve of converter cabinet two and close the first outlet butterfly valve of converter cabinet one.

[0017] Preferably, during the peak electricity price period, when the capacity of converter cabinet 2 is reduced to 30,000 m 3 When the capacity of converter cabinet 1 is reduced to 20,000 m3, the first outlet butterfly valve of converter cabinet 1 is opened again to reduce the capacity, and the second outlet butterfly valve of converter cabinet 2 is closed until the capacity of converter cabinet 1 is reduced to 20,000 m3. 3 At this time, the second outlet butterfly valve of converter cabinet 2 is opened again and the first outlet butterfly valve of converter cabinet 1 is closed, and the release operation of the converter gas stored in converter cabinet 1 is completed.

[0018] Preferably, the operating range of the blast furnace gas tank capacity is 20,000-85,000 m 3 The control target of cabinet capacity during operation is 30,000-50,000 m 3 , the piston speed is controlled within ±2.0m / min.

[0019] Preferably, the first users include hot blast furnaces and steel rolling mills, among which the steel rolling mills can implement peak-shifting power generation like gas-fired generator sets; the second users include sintering and steelmaking plants.

[0020] Compared with the prior art, the beneficial effects of the present invention are: based on the change of cabinet capacity to achieve peak-shifting power generation, the time value of electric energy is fully exploited, and the efficiency of gas power generation is improved. In the valley period and peak period of electricity price, in order to fully exploit the time value of electric energy, the coal gas is allocated through the linkage between the blast furnace gas cabinet, converter cabinet 1, converter cabinet 2, gas generator set and production users, and the coal gas allocation is optimized to increase the power generation during the peak period, reduce the price of purchased electricity, reduce the company's electricity bill expenditure, maximize the power generation efficiency, and improve the company's efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention is a flow chart of a method for controlling peak-shifting power generation by linkage of three gas cabinets. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] See also Figure 1A method for controlling peak-shifting power generation by linkage of three gasholders, wherein a blast furnace gasholder, a converter cabinet 1 and a converter cabinet 2 are connected to the grid and operated, blast furnace gas is supplied to the inlet of the blast furnace gasholder, and converter gas is supplied to the inlet of the converter cabinet 1 and the converter cabinet 2. The outlet of the blast furnace gasholder is connected to a gas-fired generator set and a first user, and the outlets of the converter cabinet 1 and the converter cabinet 2 are connected to a gas-fired generator set and a second user, respectively. Among them, the gas-fired generator set can achieve peak-shifting power generation; the first user includes a hot blast furnace and a steel mill, among which the steel mill can implement peak-shifting power generation like the gas-fired generator set; the second user includes a sintering plant and a steelmaking plant.

[0024] In this embodiment, blast furnace gas and converter gas are preferentially supplied to production users such as hot blast furnaces, steel rolling mills, sintering and steel mills, while the surplus blast furnace gas and converter gas are supplied to gas-fired generator sets. Therefore, it is necessary to adjust the gas usage of gas-fired generator sets at any time according to the gas usage and cabinet capacity of production users. Gas-fired generator sets have also become an important part of gas dynamic balance and peak-shifting power generation.

[0025] During the valley period of electricity prices, the supply of blast furnace gas and converter gas is increased to increase production intensity, the use of blast furnace gas by gas-fired generator sets is reduced, and the purchase of low-priced electricity is increased. At the same time, the surplus blast furnace gas is stored in the blast furnace gas tank to keep it in a high tank capacity state, and the surplus converter gas is transferred to converter tank 1 and converter tank 2 to keep it in a high tank capacity state. During the peak period of electricity prices, the supply of blast furnace gas and converter gas is reduced, the use of blast furnace gas by gas-fired generator sets is increased, and the purchase of electricity from outside is increased to increase production intensity. The gas stored in the blast furnace gas tank, converter tank 1 and converter tank 2 is increased and transported to the gas-fired generator sets for consumption to reduce the tank capacity, while increasing the total power generation, thereby reducing the overall motor.

[0026] In this way, based on the changes in the cabinet capacity of the blast furnace gas tank, converter cabinet 1, and converter cabinet 2, staggered power generation is achieved, the time value of electricity is fully exploited, multiple gas tanks and gas media participate in regulation, the scope of regulation is expanded, and the efficiency of gas power generation is improved. In the valley period and peak period of electricity price, in order to fully exploit the time value of electricity, in this embodiment, the gas is allocated through the linkage between the blast furnace gas tank, converter cabinet 1, converter cabinet 2, gas generator set, and production users, and the gas allocation is optimized to increase the power generation during the peak period, reduce the price of purchased electricity, reduce the company's electricity bill expenditure, maximize the power generation efficiency, and improve the company's efficiency.

[0027] Among them, the blast furnace gas tank is responsible for storing blast furnace gas and stabilizing pressure, the converter tank 2 is responsible for storing and transporting converter gas, and the converter tank 1 is used as a backup to regulate and distribute converter gas. The operating range of the blast furnace gas tank capacity is 20,000-85,000m 3 The control target of cabinet capacity during operation is 30,000-50,000 m 3, the piston speed is controlled within ±2.0m / min. The control of specific cabinet capacity shall be carried out in accordance with the requirements of the general dispatching room first, followed by the gas generator set to perform the main adjustment according to the above cabinet capacity requirements, and the converter cabinet 1 and converter cabinet 2 to perform auxiliary adjustment.

[0028] Under normal production conditions, the operating range of the converter cabinet 1 and converter cabinet 2 is 15,000-65,000 m 3 The control target of the converter cabinet 2 when it is put into operation is 30,000-50,000m 3 The converter cabinet is kept in standby state when it is out of operation. The converter gas storage capacity in standby state is 15,000 m 3 .

[0029] In this embodiment, there is a pressure difference between the converter cabinet 1 and the converter cabinet 2.

[0030] During the electricity price valley period, more gas should be stored and less electricity should be generated, and more low-priced electricity should be purchased. 3 When the first outlet butterfly valve of converter cabinet 1 is opened, part of the converter gas of converter cabinet 2 is delivered to the gas power generation component through the compressor. Due to the pressure difference, the remaining part is reversed to converter cabinet 1 through the first outlet butterfly valve. When the cabinet capacity of converter cabinet 1 reaches 65,000 m 3 When the first outlet butterfly valve is closed to stop the reverse flow, the storage operation of the surplus converter gas is completed. At this time, the blast furnace gas tank, converter tank one and converter tank two are all in a high cabinet capacity state.

[0031] During the peak electricity price period, more gas should be delivered to generate more electricity and reduce the use of purchased electricity. 3 When the first outlet butterfly valve of converter cabinet 1 is opened, the second outlet butterfly valve of converter cabinet 2 is closed, converter cabinet 1 supplies converter gas to the gas generator set, and converter cabinet 2 recovers and stores the converter gas.

[0032] During the peak electricity price period, the capacity of converter cabinet 1 is reduced to 20,000 m 3 , if the capacity of converter cabinet 1 is reduced and the capacity of converter cabinet 2 is increased to 50,000 m 3 , then suspend the capacity reduction operation of converter cabinet one, open the second outlet butterfly valve of converter cabinet two and close the first outlet butterfly valve of converter cabinet one.

[0033] During the peak electricity price period, when the capacity of converter cabinet 2 is reduced to 30,000 m 3 When the capacity of converter cabinet 1 is reduced to 20,000 m3, the first outlet butterfly valve of converter cabinet 1 is opened again to reduce the capacity, and the second outlet butterfly valve of converter cabinet 2 is closed until the capacity of converter cabinet 1 is reduced to 20,000 m3. 3 At this time, the second outlet butterfly valve of converter cabinet 2 is opened again and the first outlet butterfly valve of converter cabinet 1 is closed. At this point, the release operation of the converter gas stored in converter cabinet 1 is completed.

[0034] The above is a three-cabinet linkage operation cycle for off-peak power generation from the electricity price valley period to the electricity price peak period.

[0035] In this embodiment, a first inlet butterfly valve is provided at the inlet end of converter cabinet 1 relative to its outlet end, a first inlet water seal is provided at the front end of the first inlet butterfly valve, and a first outlet water seal is provided between the first outlet butterfly valve and converter cabinet 1. A second inlet butterfly valve is provided at the inlet end of converter cabinet 2 relative to its outlet end, a second inlet water seal is provided at the front end of the second inlet butterfly valve, and a second outlet water seal is provided between the second outlet butterfly valve and converter cabinet 2.

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling peak-shifting power generation by linkage of three gas cabinets, characterized in that: The blast furnace gas holder, converter cabinet 1 and converter cabinet 2 are connected to the grid for operation, the outlet of the blast furnace gas holder is connected to the gas generator set and the first user, and the outlet of the converter cabinet 1 and converter cabinet 2 are connected to the gas generator set and the second user respectively; During the electricity price valley period, the supply of blast furnace gas and converter gas is increased to increase production intensity, the use of blast furnace gas by gas-fired generators is reduced, and more low-priced electricity is purchased. At the same time, the surplus blast furnace gas is stored in the blast furnace gas tank to keep it in a high tank capacity state, and the surplus converter gas is transferred to converter tank 1 and converter tank 2 to keep it in a high tank capacity state; During peak electricity price periods, reduce the supply of blast furnace gas and converter gas, increase the use of blast furnace gas by gas-fired generator sets, increase external electricity purchases to increase production intensity, and increase the gas stored in the blast furnace gas tank, converter tank one, and converter tank two to be transported to the gas-fired generator sets for consumption to reduce the tank capacity.

2. The method for controlling peak-shifting power generation by linkage of three gas cabinets according to claim 1 is characterized in that: The blast furnace gas tank is responsible for storing blast furnace gas and stabilizing the pressure, the converter tank 2 is responsible for storing and transporting the converter gas, and the converter tank 1 is used as a backup to regulate and distribute the converter gas.

3. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 2 is characterized in that: Under normal production conditions, the operating range of the converter cabinet 1 and converter cabinet 2 is 15,000-65,000 m 3 .

4. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 3 is characterized in that: The control target of the converter cabinet 2 when it is put into operation is 30,000-50,000m 3 The converter cabinet is kept in standby state when it is out of operation. The converter gas storage capacity in standby state is 15,000 m 3 .

5. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 4 is characterized in that: There is a pressure difference between the converter cabinet 1 and the converter cabinet 2. During the electricity price valley period, when the cabinet capacity of the converter cabinet 2 is greater than 50,000 m 3 When the first outlet butterfly valve of converter cabinet 1 is opened, part of the converter gas of converter cabinet 2 is delivered to the gas power generation component through the compressor, and the remaining part is reversed to converter cabinet 1 through the first outlet butterfly valve. When the cabinet capacity of converter cabinet 1 reaches 65,000 m 3 Close the first outlet butterfly valve.

6. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 4 is characterized in that: During the peak electricity price period, when the capacity of converter cabinet 2 is less than 20,000 m 3 When the first outlet butterfly valve of converter cabinet 1 is opened, the second outlet butterfly valve of converter cabinet 2 is closed, converter cabinet 1 supplies converter gas to the gas generator set, and converter cabinet 2 recovers and stores the converter gas.

7. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 6 is characterized in that: During the peak electricity price period, the capacity of converter cabinet 1 is reduced to 20,000 m 3 , if the capacity of converter cabinet 1 is reduced and the capacity of converter cabinet 2 is increased to 50,000 m 3 , then suspend the capacity reduction operation of converter cabinet one, open the second outlet butterfly valve of converter cabinet two and close the first outlet butterfly valve of converter cabinet one.

8. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 7 is characterized in that: During the peak electricity price period, when the capacity of converter cabinet 2 is reduced to 30,000 m 3 When the capacity of converter cabinet 1 is reduced to 20,000 m3, the first outlet butterfly valve of converter cabinet 1 is opened again to reduce the capacity, and the second outlet butterfly valve of converter cabinet 2 is closed until the capacity of converter cabinet 1 is reduced to 20,000 m3. 3 At this time, the second outlet butterfly valve of converter cabinet 2 is opened again and the first outlet butterfly valve of converter cabinet 1 is closed, and the release operation of the converter gas stored in converter cabinet 1 is completed.

9. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 2 is characterized in that: The operating range of the blast furnace gas tank capacity is 20,000-85,000 m 3 The control target of cabinet capacity during operation is 30,000-50,000 m 3 , the piston speed is controlled within ±2.0m / min.

10. The method for controlling peak-shifted power generation by linkage of three gas cabinets according to claim 1 is characterized in that: The first users include hot blast furnaces and steel rolling mills, among which the steel rolling mills can implement peak-shifting power generation like gas-fired generator sets; the second users include sintering and steelmaking plants.

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