CN209761509U - System for reducing station power consumption rate of waste incineration power plant - Google Patents

Abstract

The utility model discloses a system for reduce waste incineration power plant station service power consumption, including taking out condensing steam turbine, one-level steam extraction female pipe, electrical control valve, back pressure steam turbine, freewheel clutch, draught fan, motor, feed pump, oxygen-eliminating device, sludge drying machine. The extracted steam of the extraction condensing steam turbine is supplied to the low-pressure section of the air preheater for steam, drives the induced draft fan for steam and drives the water supply pump for steam after the flow of the extracted steam is regulated by the electric regulating valve. The water feed pump and the induced draft fan realize steam-electricity combined driving. After the steam driving the water supply pump works through the back pressure turbine, the steam discharge parameters are matched with the steam parameter requirements required by the deaerator, and the steam is supplied to the deaerator; after the steam for driving the induced draft fan works through the back pressure steam turbine, the steam discharge parameters are matched with the steam parameter requirements required by the sludge drier (or the heat supply system) and are used for the sludge drier (or the heat supply system). The utility model discloses system safe and reliable, economical and practical, operation are stable, utilize through the energy step, reduce the station service power rate when improving the thermal efficiency of whole factory.

Description

System for reducing station power consumption rate of waste incineration power plant

Technical Field

The utility model relates to a msw incineration power generation technical field specifically is a system for reduce waste incineration power plant factory power consumption.

Background

In recent years, the waste incineration industry is increasingly competitive, the per ton waste treatment charge is lower and lower, and the profitability of enterprises is gradually weakened. In order to obtain good economic benefits, the waste incineration disposal enterprises implement 'open source throttling', the heat efficiency is improved, the plant power consumption is reduced, and the increase of the network capacity is a necessary trend.

The waste incineration power generation has lower thermal efficiency and higher plant power consumption rate due to the particularity of the waste incineration power generation. The main factors are: 1) the high moisture and low heat value of the municipal solid waste, and the dust and various complex components in the flue gas cause the heat recovery in the combustion chamber to have limitations; 2) the thermal power of the incineration boiler is relatively small, the parameters of the produced main steam are low, and the energy in a thermodynamic system is not utilized in a gradient manner, so that huge waste is caused; 3) in order to ensure that the inlet flue gas temperature of the flue gas purification treatment system meets the requirements, the boiler exhaust gas temperature is far higher than that of a thermal power plant; 4) because the harmful components in the flue gas generated by the waste incineration are more, a complex flue gas purification treatment system is needed, and the number of auxiliary machines and the power of an induced draft fan are increased; 5) in order to make the main steam reach the design pressure, the feed pump needs to have a larger lift, which results in larger power of the feed pump;

The traditional garbage power plant adopts two-stage main steam extraction machines to respectively supply steam for heating the low-pressure section of an air preheater and steam for a deaerator, and the steam extraction system is complex. Because the steam extraction mode adopts the non-adjustable type, the fluctuation of steam extraction parameters is large, and the problems of large throttling loss or unsatisfied steam demand of parameters and the like exist. The main high-power equipment induced draft fan and the feed pump adopt pure electric drive to lead to the station service power consumption great, reduced the online electric quantity, and under the condition that does not set up emergency power supply, when the outage suddenly of whole factory, the feed pump will stop operating at once, have huge potential safety hazard.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a safe and reliable, economical and practical, the stable system that reduces waste incineration power plant station service power rate of operation to increase waste incineration power generation enterprise economic benefits.

The technical scheme of the utility model is that: a system for reducing station power consumption of a waste incineration power plant comprises a condensing steam turbine, a primary steam extraction main pipe, an electric regulating valve, a back pressure steam turbine, an overrunning clutch, a draught fan, a motor, a water feeding pump, a deaerator and a sludge drier. The primary extraction steam of the extraction condensing steam turbine enters a primary extraction main pipe, and then is led out by three branch pipes to respectively supply steam for the low-pressure section of the air preheater, the driving induced draft fan and the driving water supply pump, and each branch pipe is provided with an electric regulating valve to regulate the steam consumption. Steam of a steam-using branch for driving the water-feeding pump firstly enters a back-pressure steam turbine to do work, steam-electricity combined driving on the water-feeding pump is realized through an overrunning clutch, steam discharge parameters are matched with steam parameter requirements required by a deaerator, and steam is supplied to the deaerator for thermal deaerating of boiler water feeding; steam of a steam-using branch for driving the draught fan firstly enters the back-pressure steam turbine to do work, steam-electricity combined driving on the draught fan is achieved through the overrunning clutch, steam exhaust parameters match steam parameter requirements required by the sludge drier (or a heat supply system), and steam is supplied for the sludge drier (or the heat supply system) to dry sludge.

When in use, the motor is always kept in a running state. The induced draft fan (water supply pump) is driven by the corresponding motor alone at first, and the back pressure turbine begins to rush to change after the warm-up of one-level steam extraction heating pipe, and when the rotational speed was higher than the motor rotational speed, freewheel clutch automatic meshing realized coaxial rotation by back pressure turbine, motor, induced draft fan (water supply pump). Along with the steam inlet quantity of the back pressure turbine continues to increase, the back pressure turbine starts to work on a draught fan (a water supply pump), the working current of the motor is gradually reduced along with the increase of the work of the back pressure turbine, and the purpose of reducing the service power is achieved. When the steam inlet amount of the back pressure turbine is gradually reduced, the work amount of the back pressure turbine is gradually reduced, and the current of the motor is increased accordingly. When the steam inlet amount is reduced to the state that the rotating speed of the back pressure turbine is less than that of the motor, the overrunning clutch is separated, and the induced draft fan (water supply pump) is only driven by the motor.

The utility model has the advantages that: the system is safe, reliable, economical, practical and stable in operation, changes two-stage non-adjustable steam extraction of the original extraction condensing steam turbine into one-stage adjustable steam extraction, reduces the steam extraction stage number of the extraction condensing steam turbine, and reduces the complexity of the steam extraction system. The extracted steam is sent into the back pressure type steam turbine to do work, the steam exhaust parameter is consistent with the requirement of subsequent steam utilization equipment, the stability of the steam utilization parameter of the equipment is ensured, the throttling loss caused by mismatching of the extracted steam and the steam utilization parameter is reduced, the energy gradient utilization is realized, and the heat efficiency of the whole plant is improved. The drive motors of the water feed pump and the induced draft fan are always kept in a running state during running, the output power of the back pressure turbine is directly used for driving high-power equipment such as the water feed pump and the induced draft fan through the connection of the overrunning clutch, self-operated steam-electricity combined drive is realized, the plant power consumption rate is reduced, and the online electric quantity is increased. The system can not influence the normal start and shutdown of the boiler, and can realize the normal water supply of the water supply pump by utilizing the residual steam of the boiler under the condition of sudden power failure of the whole plant, thereby improving the safety of the boiler.

Drawings

Fig. 1 is a schematic diagram of the system of the present invention.

In the figure: 1-extraction condensing steam turbine, 2-primary extraction main pipe, 3-electric regulating valve, 4-back pressure steam turbine, 5-overrunning clutch, 6-induced draft fan, 7-motor, 8-water feeding pump, 9-deaerator, 10-sludge drier (or heat supply system).

Detailed Description

The system for reducing the station power consumption of the waste incineration power plant shown in the attached drawing 1 comprises a condensing steam turbine 1, a primary steam extraction main pipe 2, an electric regulating valve 3, a back pressure steam turbine 4, an overrunning clutch 5, an induced draft fan 6, a motor 7, a water feeding pump 8, a deaerator 9 and a sludge drier 10. The primary extraction steam of the extraction condensing steam turbine 1 enters a primary extraction steam main pipe 2, and then is led out by three branch pipes to respectively supply steam for the low-pressure section of the air preheater, drive the induced draft fan 6 and drive the water supply pump 8, and each branch pipe is provided with an electric regulating valve 3 to regulate the steam consumption. Steam of a steam-using branch for driving the water-feeding pump 8 firstly enters the back-pressure steam turbine 4 to do work, steam-electricity combined driving on the water-feeding pump 8 is realized through the overrunning clutch 5, steam discharge parameters are matched with steam parameter requirements required by the deaerator 9, and the deaerator 9 supplies steam for thermal deaerating of boiler water feeding; steam of a steam-using branch for driving the draught fan 6 firstly enters the back pressure type steam turbine 4 to do work, the steam-electricity combined driving of the draught fan 6 is realized through the overrunning clutch 5, and steam exhaust parameters are matched with the steam parameter requirements required by the sludge drier 10 (or a heat supply system) and are used for drying sludge by the sludge drier 10 (or the heat supply system).

When in use, the motor 7 is kept in a running state all the time. The induced draft fan 6 (water feed pump 8) is at first driven by corresponding motor 7 alone, and the back pressure turbine 4 begins to rush to change after one-level steam extraction heating pipe warms up, and when the rotational speed was higher than motor 7 rotational speed, freewheel clutch 5 automatic meshing realized coaxial rotation by back pressure turbine 4, motor 7, induced draft fan 6 (water feed pump 8). With the steam inlet quantity of the back pressure turbine 4 continuing to increase, the back pressure turbine 4 starts to apply work to the induced draft fan 6 (the water supply pump 8), and the working current of the motor 7 gradually decreases with the increase of the work applied by the back pressure turbine 4, so that the purpose of reducing the service power is achieved. When the steam intake of the back pressure turbine 4 is gradually reduced, the work done by the back pressure turbine 4 is gradually reduced, and the current of the motor 7 is increased accordingly. When the steam inlet amount is reduced to the state that the rotating speed of the back pressure turbine 4 is less than the rotating speed of the motor 7, the overrunning clutch 5 is separated, and the induced draft fan 6 (the water supply pump 8) is driven by the motor 7 only.

The utility model discloses vapour electricity combined drive is realized to feed pump and draught fan. After the steam driving the water supply pump works through the back pressure turbine, the steam discharge parameters are matched with the steam parameter requirements required by the deaerator, and the steam is supplied to the deaerator; after the steam for driving the induced draft fan works through the back pressure steam turbine, the steam discharge parameters are matched with the steam parameter requirements required by the sludge drier (or the heat supply system) and are used for the sludge drier (or the heat supply system). The steam for heating the air preheater, drying the sludge and deoxidizing by the deaerator comes from the same stage of steam extraction, so that the steam extraction stages are reduced. The first-stage extraction steam from the main steam turbine works through the back pressure steam turbine to realize steam-electricity combined drive of the feed water pump and the induced draft fan. The back pressure turbine is used for applying work to replace a temperature and pressure reducing device to reduce the primary steam extraction parameters, so that the throttling loss is reduced, and the matching of the steam exhaust with the deaerator and the steam demand parameters of the sludge drying machine is realized.

Claims (1)

1. a system for reducing station power consumption rate of a waste incineration power plant is characterized by comprising a condensing steam turbine, a primary steam extraction main pipe, an electric regulating valve, a back pressure steam turbine, an overrunning clutch, an induced draft fan, a motor, a water feeding pump, a deaerator and a sludge drier; after primary extraction steam of the extraction condensing steam turbine enters a primary extraction main pipe, three branch pipes are led out for supplying steam to a low-pressure section of an air preheater, driving a draught fan to use steam and driving a water supply pump to use steam respectively, and each branch pipe is provided with an electric regulating valve for regulating the steam consumption; steam of a steam-using branch for driving the water-feeding pump firstly enters a back-pressure steam turbine to do work, steam-electricity combined driving on the water-feeding pump is realized through an overrunning clutch, steam discharge parameters are matched with steam parameter requirements required by a deaerator, and steam is supplied to the deaerator for thermal deaerating of boiler water feeding; steam of a steam-using branch for driving the draught fan firstly enters the back-pressure steam turbine to do work, steam-electricity combined driving on the draught fan is achieved through the overrunning clutch, steam exhaust parameters match steam parameter requirements required by the sludge drier or the heat supply system, and the steam is supplied to the sludge drier or the heat supply system for drying sludge.