CN201071741Y - Electric furnace flue gas waste heat power generation system - Google Patents

Abstract

The utility model discloses a waste heat power generation system of electric furnace flue gas, which is invented in order to solve problems of the prior electric furnace on unsuitable utilization of the flue gas with high temperature and high dust. The utility model comprises a flue gas & air system, a steam system, a steam turbine, a water system and a waste heat boiler; through adopting steam thermal storage technology and steam turbine power generation technology, the system can sufficiently utilize the steam produced by the waste heat boiler, thereby realizing objective on energy conservation, consumption reduction and emission reduction of electric furnace steelmaking, expanding method of waste heat utilization, reducing enterprise manufacturing cost, and improving enterprise market competitiveness, which can create valuable economic benefit, environmental benefit and social benefit with more impact.

Description

Electric furnace flue gas waste heat power generation system

technical field

The utility model relates to a power generation system, in particular to a power generation system utilizing the waste heat of electric furnace waste flue gas.

Background technique

In the existing technology, electric furnace steelmaking will produce a large flow of high-temperature and high-dust flue gas. Affected by the production cycle of the electric furnace, the exhaust heat of the flue gas is intermittent, fluctuating and periodic, resulting in waste of this part of energy. At the same time, in order to meet the requirements of the dust removal equipment, the high-temperature flue gas must be cooled by a mechanical air cooler, and a large amount of power electricity is required to support the operation of the cooling system during the process.

Utility model content

In order to overcome the above defects, the utility model provides an electric furnace flue gas waste heat power generation system that can save energy and reduce production costs.

In order to achieve the above purpose, the electric furnace flue gas waste heat power generation system of the utility model includes a flue gas system, a steam system, a steam turbine, a water system and a waste heat boiler;

Flue gas system: composed of electric furnace, combustion settling chamber, heating surface of waste heat boiler, dust removal system, induced draft fan, and chimney; among them, the high-temperature flue gas generated by electric furnace is output to the heating surface of waste heat boiler through combustion settling chamber, and the high-temperature flue gas After the heat release is completed, it is output to the dust removal system, and then output to the chimney through the induced draft fan and then discharged;

Steam system: including waste heat boiler, heat accumulator and steam dryer; among them, the high-quality steam generated by waste heat boiler is output to steam turbine through heat accumulator, steam dryer;

Water system: composed of condenser, condensate tank, condensate pump, deaerator, heat storage pump, circulating water pump, waste heat boiler system; among them, the waste steam discharged from the outlet of the steam turbine passes through the condenser, condensate tank, condensate pump, Deaerator, accumulator water pump, water pump return to waste heat boiler.

Further, it also includes a heating system connected to the heat accumulator, the heating system includes heating users, heat exchange stations, and heat users; wherein, the high-quality steam in the heat accumulator supplies heat to the heating users through the heat exchange station .

Among them, the above-mentioned waste heat boilers are two or more; a sub-cylinder is provided between the above-mentioned multiple waste heat boilers and the heat accumulator, and the two or more waste heat boilers are supplied to the heat storage through the sub-cylinders. steam output from the appliance.

Wherein, the above-mentioned heat accumulators are two or more, and the two or more heat accumulators are connected in series or in parallel.

Wherein, the above-mentioned steam dryer is: a steam-water separator, a steam superheater or a steam mixer.

Further, a mechanical air cooler is provided between the combustion settling chamber and the dust removal system.

The utility model has the following advantages:

1. In the waste heat power generation system of the electric furnace waste gas of the present utility model, the high temperature flue gas of the electric furnace passes through the waste heat boiler to generate saturated steam, and the saturated steam drives the turbogenerator unit to generate electricity, fully recycles and utilizes the waste heat of the electric furnace flue gas, saves energy and reduces Production cost, reduced environmental pollution of flue gas;

2. When the system encounters a failure or needs to be repaired, the flue gas generated by the electric furnace can be cooled by the mechanical air cooling system and then dust and smoke are removed to ensure the normal and stable operation of the main steelmaking process;

3. The steam accumulator is used in the system to adjust the peak and valley of the steam produced by the waste heat boiler, so as to realize "peak shaving and filling valley, so that the power generation and heating system can operate stably.

Description of drawings

Fig. 1 is a structural schematic diagram of the electric furnace flue gas waste heat power generation system of the present invention.

Fig. 2 is a schematic structural diagram of the connection of two waste heat boilers in the electric furnace flue gas waste heat power generation system shown in Fig. 1 of the present invention.

Fig. 3 is a structural schematic diagram of the heating system in the utility model electric furnace flue gas waste heat power generation system shown in Fig. 1 .

Fig. 4 is a structural schematic diagram of parallel use of regenerators in the utility model electric furnace flue gas waste heat power generation system shown in Fig. 1 .

Fig. 5 is a schematic diagram of the structure of heat accumulators used in series in the electric furnace flue gas waste heat power generation system shown in Fig. 1 of the present invention.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described further.

The utility model absorbs the heat of the flue gas through the waste heat boiler to generate saturated water vapor, and uses the saturated water vapor to drive the steam turbine to do work and generate clean electric energy. As shown in Figure 1, the electric furnace flue gas waste heat power generation system of the utility model includes a flue gas system, a steam system, a steam turbine, a water system and a waste heat boiler;

Flue air system: composed of electric furnace 14, combustion settling chamber 15, heating surface of waste heat boiler, dust removal system 17, induced draft fan 18, and chimney 19;

Steam system: including waste heat boiler 1, heat accumulator 3 and steam dryer 4;

Water system: composed of condenser 7, condensate tank 8, condensate pump 9, deaerator 10, heat accumulator water pump 11, circulating water pumps 12, 13, waste heat boiler 1;

The working process of the entire power generation system is as follows: the flue gas with high temperature and high dust is cooled by the waste heat boiler 1 and then enters the dust removal equipment 17, and the flue gas after dust removal enters the chimney 19 through the induced draft fan 18 and is discharged into the atmosphere. The water from the water supply system absorbs heat on the heating surface 1 of the boiler and becomes a mixture of saturated water and steam. The steam and water are separated in the steam drum 27, and the water returns to the heating surface to absorb heat. The steam flows into the distribution cylinder 2 and passes through the separation Part of the cylinder 2 enters the steam-water separator 4 and then enters the steam turbine 5 to do work to drive the generator 6 to generate electricity, and part of it enters the heat accumulator 3 for storage. The finished steam enters the condensed water tank 8 after being condensed in the condenser 7, the condensed water enters the deaerator 10 through the condensed water pump 9, and the deaerated water enters the boiler steam drum through the feed water pumps 12 and 13 so as to circulate. A part of the water coming out of the deaerator 10 enters the heat accumulator 3 through the heat accumulator water pump 11 . Make-up water from the desalinated water system is added to the condensate tank of the condenser.

As a further improvement of the utility model, as shown in Fig. 1 and Fig. 3, the system can isolate the turbogenerator, use the generated steam to directly supply heat to the user 30, and can also provide heat to the community through the heat exchange station 29 28, or expand the heating radius through the heat pump system to realize power supply in summer and heating in winter, or triple supply of heat, electricity and heating.

As shown in Figure 2, as a further improvement of the utility model, there are two or more waste heat boilers; a sub-cylinder is arranged between the multiple waste heat boilers and the heat accumulator, and the two waste heat boilers One or more waste heat boilers output steam to the heat accumulator through the sub-cylinder.

As shown in Figure 4 and Figure 5, the number of the above-mentioned heat accumulators can be selected according to the needs, which can be one or two or more, and two or more heat accumulators can be connected in series or in parallel. connect.

During specific implementation, the power in the system can fully use electric energy such as the water pump 13;

During specific implementation, the steam-water separator 4 can be replaced by the steam superheater 25 to reheat the saturated steam into superheated steam, and use the superheated steam to generate electricity. The temperature of the superheated steam is 300-450°C. The heating heat source can be electric energy, high-temperature flue gas heat energy, solar energy and other energy sources; it can also be replaced with a steam mixer 26, which can be mixed with high-temperature and high-pressure steam to achieve the purpose of superheating.

In order to prevent the normal and stable operation of the main steelmaking process when the system runs into failure or needs maintenance; a mechanical air cooler 16 is provided between the combustion settling chamber 15 and the dust removal system 17, so that the combustion settling chamber 15 and A switch valve 23 is set on the pipeline between the mechanical air cooler 16 , and a switch valve 24 is set on the pipeline between the combustion settling chamber 15 and the waste heat boiler 1 . When the system needs maintenance, open the switching valve 23 and close the switching valve 24. The flue gas generated by the electric furnace can be cooled by the mechanical air cooler and then dust and smoke are removed, so as to ensure the normal and stable operation of the main steelmaking process.

During the specific implementation, the flue gas with high dust content enters the waste heat boiler, and the gas shock wave technology is used to remove dust to ensure the stable, safe and efficient operation of the boiler. The outlet flue gas is exhausted after dust removal, which can effectively protect the dust collector and prolong its service life.

In summary, the system can make full use of the steam produced by the electric furnace by adopting the steam heat storage technology and the steam turbine power generation technology. In this way, the goal of energy saving, consumption reduction and emission reduction in electric furnace steelmaking is realized, the way of waste heat utilization is expanded, the production cost of the enterprise is reduced, and the market competitiveness of the enterprise is improved. Of course, those skilled in the art should know that this system is not only applicable to electric furnace flue gas waste heat recovery and utilization systems, but also widely applicable to waste heat sources with recovery value.

Claims (6)

1. An electric furnace flue gas waste heat power generation system is characterized in that: it comprises a flue gas system, a steam system, a steam turbine, a water system and a waste heat boiler; Flue gas system: composed of electric furnace, combustion settling chamber, heating surface of waste heat boiler, dust removal system, induced draft fan, and chimney; among them, the high-temperature flue gas generated by electric furnace is output to the heating surface of waste heat boiler through combustion settling chamber, and the high-temperature flue gas After the heat release is completed, it is output to the dust removal system, and then output to the chimney through the induced draft fan and then discharged; Steam system: including waste heat boiler, heat accumulator and steam dryer; among them, the high-quality steam generated by waste heat boiler is output to steam turbine through heat accumulator, steam dryer; Water system: composed of condenser, condensate tank, condensate pump, deaerator, heat storage pump, circulating water pump, waste heat boiler system; among them, the waste steam discharged from the outlet of the steam turbine passes through the condenser, condensate tank, condensate pump, Deaerator, accumulator water pump, water pump return to waste heat boiler. 2. The electric furnace flue gas waste heat power generation system according to claim 1, characterized in that: it also includes a heating system connected to the heat accumulator, and the heating system includes a heating user, a heat exchange station, and a heat user; wherein , the high-quality steam in the accumulator supplies heat to heating users through the heat exchange station. 3. The electric furnace flue gas waste heat power generation system according to claim 1, characterized in that: there are two or more waste heat boilers; the two or more waste heat boilers and heat accumulators A sub-cylinder is arranged between them, and the two or more waste heat boilers output steam to the heat accumulator through the sub-cylinders. 4. The electric furnace flue gas waste heat power generation system according to claim 1, characterized in that: there are two or more heat accumulators, and two or more heat accumulators are connected in series or in parallel connect. 5. The electric furnace flue gas waste heat power generation system according to claim 1, characterized in that: the steam dryer is a steam-water separator, a steam superheater or a steam mixer. 6. The electric furnace flue gas waste heat power generation system according to claim 1, characterized in that: a mechanical air cooler is provided between the combustion settling chamber and the dust removal system.

Images