CN204804891U - Steam electric power system - Google Patents

Abstract

The utility model provides a steam power generation system, which belongs to the technical field of residual energy power generation, and can solve the problem in the prior art that low-pressure saturated steam produced by a coking process cannot effectively perform thermoelectric conversion. The steam power generation system of the utility model adopts the main steam and supplementary steam to jointly drive the supplementary steam condensing generator to generate electricity, thereby effectively utilizing the low-pressure saturated steam produced by the waste heat recovery device, and improving the comprehensive utilization rate of surplus energy. Strong power generation capacity, good power generation stability, low operation and maintenance costs, and significant energy-saving and economic benefits.

Description

A steam power generation system

technical field

The utility model belongs to the technical field of residual energy power generation, in particular to a steam power generation system.

Background technique

Coking products are one of the main raw materials needed for the production of my country's steel and other industries. At present, the national production capacity is more than 600 million tons. my country is already the world's largest coke producer, consumer and exporter. In recent years, in order to encourage the transformation and development of the coking industry, energy conservation and emission reduction, China has successively issued a series of policies and regulations, emphasizing "promoting the efficient recovery and utilization of secondary energy such as dry coke quenching and coke oven gas". Encourage or mandate the transition from wet coke quenching to dry coke quenching in coking plants, and encourage the effective use of waste heat in coking plants. Therefore, dry coke quenching waste heat power generation technology has been rapidly developed and popularized in the past ten years. At the same time, in order to further improve the level of energy saving and consumption reduction in coking plants, a large number of energy-saving and consumption-reducing projects, such as coke oven flue gas waste heat recovery devices and coke oven riser waste heat recovery devices, have also been widely implemented.

Due to the limitations of the production process and conditions, the steam generated by these waste heat recovery devices is low-grade saturated steam, which is characterized by low pressure and high water content. These low-pressure saturated steams are not only used by coking plants for their own use, but also in some plants. If this part of steam cannot be fully utilized, a large amount of waste heat resources will be wasted. If the low-pressure saturated steam is not used by users, it will restrict the input of waste heat recovery equipment and cause energy waste.

Dry coke quenching is to use colder circulating gas to exchange heat with red coke in the dry quenching furnace. The circulating gas that absorbs the heat of red coke is introduced into the boiler to recover heat and generate steam. The circulating gas is cooled and dedusted and then returned to CDQ by the fan. The heat exchange is carried out again in the furnace, so the cycle is repeated. This method of producing coke can not only reduce the discharge of pollutants, but also improve the quality of coke. Moreover, the sensible heat of red coke can be recovered to generate steam for power generation.

The waste heat power generation process of the traditional dry coke quenching system: the high temperature and high pressure or medium temperature and medium pressure steam generated by the dry coke quenching boiler is connected to the high pressure section of the steam turbine unit in the steam turbine power station through the steam pipeline, and the steam turbine is driven to drive the generator for power generation. ; The exhausted steam after doing work is condensed into water in the condenser and returned to the pumping station for recycling.

However, this kind of power generation system is relatively independent, and can only use the steam generated by the dry coke quenching boiler to generate electricity, and cannot use the low-pressure saturated steam generated by various waste heat recovery devices. If the low-pressure saturated steam is to be used for power generation, the existing dry coke quenching steam turbine power station cannot be used directly. It is necessary to build a new low-pressure saturated steam turbine generator set, which will increase the floor area, and because the temperature of the saturated steam is too low, it will cause The thermal efficiency of the power generation system is low, the power generation is small, and the heat energy cannot be effectively utilized.

Utility model content

The purpose of the utility model is to solve the problem in the prior art that the low-pressure saturated steam produced by the coking process cannot effectively perform thermoelectric conversion.

The technical solution adopted to solve the technical problems of the utility model is a steam power generation system, including: a steam supplementary condensing generator and a steam source for providing steam to the steam supplementing condensing generator; the steam supplementing condensing generator including an admission steam condensing turbine and a generator driven by the admission steam condensing turbine;

The steam source includes a main steam source and a supplementary steam source; the main steam source provides steam to the high pressure section of the supplementary steam condensing turbine, and the supplementary steam source supplies steam to the low pressure section of the supplementary steam condensing turbine Provide steam.

Preferably, the main steam source includes a dry coke quenching boiler for generating steam.

Preferably, the main steam source provides steam to the high-pressure section of the steam-enrichment condensing turbine through a main steam delivery unit, and the main steam delivery unit includes a high-pressure regulating valve and a main steam quick-closing valve; the high-pressure regulating valve It is used to adjust the intake of main steam; the main steam quick-closing valve is used to quickly stop the supply of main steam when the steam-admission condensing turbine fails.

Preferably, the supplementary steam source includes a waste heat recovery device for generating steam.

Preferably, the waste heat recovery device includes a coke oven flue gas waste heat recovery device or a coke oven riser waste heat recovery device.

Preferably, the supplementary steam source provides steam to the low-pressure section of the supplementary steam condensing turbine through a supplementary steam delivery unit, and the supplementary steam delivery unit includes a supplementary steam distribution regulating valve and a supplementary steam quick-closing valve; The steam regulating valve for auto parts is used to adjust the intake steam volume of the supplementary steam; the supplementary steam quick-closing valve is used to quickly stop the supplementary steam supply when the supplementary steam condensing steam turbine fails.

Preferably, the supplementary steam delivery unit further includes a steam-water separation device for controlling the dryness of the supplementary steam.

Preferably, a condenser for condensing exhaust steam passing through the steam-admission condensing turbine is also included.

Preferably, a pump for pumping and recycling the condensed water of the condenser is also included.

Preferably, the pump includes a variable frequency pump.

The steam power generation system of the utility model adopts the main steam and the supplementary steam to jointly drive the supplementary steam condensing generator to generate electricity, thereby effectively utilizing the low-pressure saturated steam produced by the waste heat recovery device, and improving the comprehensive utilization rate of surplus energy. Strong power generation capacity, good power generation stability, low operation and maintenance costs, and significant energy-saving and economic benefits.

Description of drawings

Fig. 1 is a schematic diagram of the composition of the steam power generation system in Embodiment 1 of the present utility model.

in:

1. Dry coke quenching boiler; 2. Main steam delivery unit; 21. Main steam quick closing valve; 22. High pressure regulating valve;

3. Steam intake condensing generator; 31. Steam intake condensing turbine; 32. Generator;

4. Waste heat recovery device;

5. Supplementary steam delivery unit; 51. Supplementary steam quick-closing valve; 52. Supplementary steam distribution steam regulating valve; 53. Steam-water separation device;

6. Condenser;

7. Pump;

8. Low-pressure saturated steam users.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the utility model, the utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

As shown in Figure 1, the present embodiment provides a steam power generation system, including: a steam-admission condensing generator 3 and a steam source for providing steam to the steam-admission condensing generator 3; 3 comprising an intake steam condensing turbine 31 and a generator 32 driven by the intake steam condensing turbine 31;

The steam source includes a main steam source and a supplementary steam source; the main steam source provides steam to the high-pressure section of the supplementary steam condensing turbine 31, and the supplementary steam source supplies steam to the high pressure section of the supplementary steam condensing turbine 31. The low pressure section provides steam.

The steam power generation system provided in this embodiment uses the main steam and the supplementary steam to jointly drive the supplementary steam condensing generator 3 to generate electricity, thereby effectively utilizing the low-pressure saturated steam produced by the waste heat recovery device 4, and improving the comprehensiveness of residual energy. The utilization rate has remarkable energy-saving and economic benefits.

Preferably, the main steam source includes a dry coke quenching boiler 1 for generating steam.

Preferably, the main steam source provides steam to the high-pressure section of the steam-enrichment condensing turbine 31 through the main steam delivery unit 2, and the main steam delivery unit 2 includes a high-pressure regulating valve 22 and a main steam quick-closing valve 21; The high-pressure regulating valve 22 is used to adjust the intake of main steam; the main steam quick-closing valve 21 is used to quickly stop the supply of main steam when the steam-admission condensing turbine 31 fails.

Taking the coking process as an example, the high-temperature and high-pressure (9.81MPa, 540°C) or medium-temperature and medium-pressure steam (3.82MPa, 450°C) generated by the dry coke quenching boiler 1 is passed through the main steam delivery unit 2 into the steam-enhancing condensing turbine 31 In the high-pressure section, the flow rate is adjusted to drive the steam-admission condensing turbine 31 to rotate to make the generator generate electricity. It should be understood that the superheated steam produced by the dry coke quenching boiler is not limited to high temperature and high pressure, medium temperature and medium pressure superheated steam, and can also be superheated steam with sub-high pressure and other parameters, so I won’t go into details here.

Preferably, the supplementary steam source includes a waste heat recovery device 4 for generating steam.

Taking the coking process as an example, the waste heat recovery device 4 includes a coke oven flue gas waste heat recovery device or a coke oven riser waste heat recovery device; it should be understood that it can also be other waste heat recovery devices.

Preferably, the supplementary steam source provides steam to the low-pressure section of the supplementary steam condensing turbine 31 through the supplementary steam delivery unit 5, and the supplementary steam delivery unit 5 includes a supplementary steam distribution regulating valve 52 and a supplementary steam quick-closing valve 51; the supplementary steam distribution regulating valve 52 is used to adjust the intake steam volume of the supplementary steam; specifically, when adjusting the flow rate of the supplementary steam, the pressure of the supplementary steam is adapted to the pressure of the low-pressure section of the supplementary steam condensing turbine 31 . For example, when the pressure of supplementary steam entering before the supplementary steam condensing turbine 31 is high, the flow rate of the steam valve is increased to allow more supplementary steam to enter the supplementary steam condensing turbine 31 to increase the power generation;

When the pressure of the supplementary steam before entering the supplementary steam condensing steam turbine 31 is low, reduce the flow rate of the steam valve, maintain the inlet steam pressure of the condensing steam supplementary steam turbine, reduce the power generation, and ensure the stable operation of the steam turbine.

The supplementary steam quick-closing valve 51 is used to quickly stop the supplementary steam supply when the supplementary steam condensing turbine 31 fails.

Taking the coking process as an example, the low-pressure saturated steam (0.4-0.6MPa or 0.6-0.8MPa, saturation temperature) generated by the waste heat recovery device 4 is passed through the supplementary steam delivery unit 5 into the low-pressure section of the condensing steam supplementary steam turbine to drive the supplementary steam The condensing turbine 31 rotates to generate electricity from the generator.

It should be understood that, as mentioned above, there may be multiple waste heat recovery devices 4 , and the above-mentioned low-pressure saturated steam may also be directly delivered to other types of low-pressure saturated steam users 8 , and there may be multiple low-pressure saturated steam users 8 .

Preferably, the supplementary steam delivery unit 5 further includes a steam-water separation device 53 for controlling the dryness of the supplementary steam.

In this way, the dryness of the supplementary steam can be guaranteed to meet the requirements of the supplementary steam condensing steam turbine, and the safe and stable operation of the supplementary steam condensing steam turbine can be guaranteed.

Preferably, a condenser 6 for condensing the exhaust steam passing through the steam-admission condensing turbine is also included.

Setting the condenser 6 can recycle the condensed water for recycling, reducing the amount of water and saving costs.

Preferably, a pump 7 for pumping and recycling the condensed water of the condenser 6 is also included. It should be understood that the pump group can also be used to transport the above-mentioned condensed water to the waste heat recovery device 4 or the dry coke quenching boiler 1 for reuse through pipelines.

Preferably, the pump 7 includes a variable frequency pump.

Since the motor of the frequency conversion pump can adapt to the load change of the generator, the electricity cost can be saved.

The steam power generation system provided in this embodiment also has the following advantages:

1. Generally, steam turbines are used to generate electricity. In order to improve the efficiency of the Rankine cycle, the superheat of the low-pressure saturated steam will be increased, that is, the low-pressure saturated steam will be heated to consume energy again; the steam power generation system of this embodiment does not need to use the low-pressure saturated steam processed directly to generate electricity.

2. The steam power generation system in this embodiment can directly comprehensively utilize low-pressure saturated steam and high-temperature and high-pressure steam or medium-temperature and medium-pressure steam. Therefore, for the coking plant of a new dry coke quenching steam turbine power station, only a new steam turbine power station is needed That's it. For the coking plant of the existing dry coke quenching steam turbine power station, there is no need to build a new plant, only the transformation of the corresponding generator set is required, making full use of the original site, saving land, and the system is simple and easy to maintain.

The following briefly introduces the method of using the above-mentioned steam power generation system, including the following steps:

S1: The steam generated by the main steam source is introduced into the high-pressure section of the steam-enhancing condensing turbine after the flow is adjusted;

S2: Separating the steam generated by the supplementary steam source;

S3: Adjust the flow rate of the supplementary steam that will undergo steam-water separation;

S4: Introduce the flow-regulated admission steam into the low-pressure section of the admission steam condensing turbine.

S5: Condensate and recycle exhaust steam.

It can be understood that, the above embodiments are only exemplary embodiments adopted to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present utility model, and these variations and improvements are also regarded as the protection scope of the present utility model.

Claims (10)

1. a steam generating system, comprising: filling condensing generator and provide the vapour source of steam to described filling condensing generator; The generator that described filling condensing generator comprises filling condensing steam turbine and driven by described filling condensing steam turbine;

It is characterized in that, described vapour source comprises main vapour source and filling source; Described main vapour source provides steam to the high pressure section of described filling condensing steam turbine, and described filling source provides steam to the low pressure stage of described filling condensing steam turbine.

2. steam generating system as claimed in claim 1, it is characterized in that, described main vapour source comprises the CDQ boiler for generation of steam.

3. steam generating system as claimed in claim 2, is characterized in that, described main vapour source provides steam by main vapour supply unit to the high pressure section of described filling condensing steam turbine, and described main vapour supply unit comprises septum valve and main steam quick-closing valve; Described septum valve is for regulating the throttle flow of main vapour; Described main steam quick-closing valve is used for stopping main vapour supply fast when described filling condensing steam turbine breaks down.

4. steam generating system as claimed in claim 1, it is characterized in that, described filling source comprises the waste heat recovering device for generation of steam.

5. steam generating system as claimed in claim 4, it is characterized in that, described waste heat recovering device comprises flue gases of cock oven waste heat recovering device or Riser waste heat recovery device for coke oven.

6. steam generating system as claimed in claim 4, is characterized in that, described filling source provides steam by filling supply unit to the low pressure stage of described filling condensing steam turbine, and described filling supply unit comprises filling and joins steam control valve and filling quick-closing valve; Described filling joins steam control valve for regulating the throttle flow of filling; Described filling quick-closing valve is used for stopping filling supply fast when filling condensing steam turbine breaks down.

7. steam generating system as claimed in claim 6, is characterized in that, described filling supply unit also comprising the water separator for controlling filling mass dryness fraction.

8. steam generating system as claimed in claim 6, is characterized in that, also comprise the condenser with carrying out condensation to the exhaust steam through described filling condensing steam turbine.

9. steam generating system as claimed in claim 8, is characterized in that, also comprising the pump with the condensed water of described condenser being carried out pumping circulation utilization.

10. steam generating system as claimed in claim 9, it is characterized in that, described pump comprises variable frequency pump.