Waste heat recycling power generation system of steel rolling bar totally-closed cooling bed

Abstract

The utility model provides a waste heat recycling power generation system of a steel rolling bar totally-closed cooling bed, which comprises a heat taking device and a steam turbine generator, and the heat taking device is connected with the steam turbine generator through a heat taking device steam pocket; the heat removal device comprises a plurality of radiant heat removers, a straightening plate heat remover set and a fixed tooth heat remover set, the straightening plate heat remover set comprises straightening plate conduction heat removers which are communicated end to end, the straightening plate conduction heat removers are arranged at the starting end of a high-temperature area of the cooling bed, and the fixed tooth heat remover set comprises fixed tooth conduction heat removers which are communicated end to end. The fixed tooth conduction heat collectors are arranged on the two sides of the cooling bed fixed tooth respectively, and the radiant heat collectors are suspended at the upper end of a rolled steel bar. The straightening plate heat collector group, the fixed tooth heat collector group and each radiant heat collector are all communicated with a water supply pipeline and a water return pipeline on the outer side of the cooling bed, and the water return pipeline is connected with a heat collector steam pocket. According to the cooling bed waste heat recovery device, radiation heat extraction and conduction heat extraction are combined, and cooling bed waste heat recovery reaches the highest efficiency.

Description

Technical Field

[0001] The utility model belongs to the technical field of waste heat recovery and utilization, and in particular relates to a waste heat recovery and utilization power generation system of a fully enclosed cooling bed for rolled steel bars. Background Art

[0002] During the steel bar rolling process in the steel industry, the steel is naturally cooled on the cooling bed, and the temperature drops, releasing a large amount of heat into the work site environment, causing a huge waste of energy. The recovery and utilization of waste heat from hot rolling cooling beds is still a blank at home and abroad. A large amount of heat is freely released, causing the work site environment to deteriorate, the equipment to deform due to high temperature, and the life span to be reduced.

[0003] According to comprehensive thermal calculations, when the hot steel parts on the cooling bed are cooled from 900℃ to room temperature, all the heat released by every 9 tons of steel can be heated to produce 1 ton of 0.5Mp steam; if the heat recovery rate is ≮50%, that is, the recyclable heat released by every 18 tons of steel can be recovered through the system to produce ≮1 ton of 0.5Mp steam, and 1 ton of 0.5Mp steam can generate 100-110 degrees of electricity, which can be directly used by steel rolling production equipment, reducing the electricity consumption of the production line by 6 degrees per ton of steel.

[0004] Therefore, in order to achieve energy conservation and consumption reduction, green production, create better economic benefits for enterprises and reduce production costs, how to recycle the waste heat of rolled steel bars is a technical problem that needs to be solved. Utility Model Content

[0005] In order to solve the above-mentioned technical problems of waste heat recovery and utilization, the main purpose of the utility model is to provide a fully enclosed cooling bed waste heat recovery and power generation system for rolled steel bars, which collects heat from the concentrated release area of ​​waste heat in the high-temperature section of the cooling bed, and adopts a combination of three heating methods: radiation heat extraction, straightening plate conduction heat extraction, and fixed tooth heat extraction from the high-temperature zone of the cooling bed to the head roller table, so as to achieve the highest efficiency in waste heat recovery of the cooling bed.

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars, characterized in that it comprises a heat extraction device and a steam turbine generator, wherein the heat extraction device is connected to the steam turbine generator via a steam drum; the heat extraction device comprises a plurality of radiant heat heat collectors, a straightening plate heat extraction group and a fixed tooth heat extraction group, the straightening plate heat extraction group comprises a plurality of straightening plate conductive heat extractions connected end to end in sequence, the straightening plate conductive heat extractions are sequentially arranged at the starting end of the high temperature zone of the cooling bed, the fixed tooth heat extraction group comprises a plurality of fixed tooth conductive heat extractions connected end to end in sequence, each fixed tooth conductive heat extraction is respectively arranged on both sides of the fixed teeth of the cooling bed, and the radiant heat extractions are sequentially suspended in parallel at the upper ends of the rolled steel bars on the cooling bed. ; The first water inlet of the straightening plate heat exchanger group and the second water inlet of the fixed tooth heat exchanger group are both connected to the water supply pipe parallel to the outside of the cooling bed, the first water outlet of the straightening plate heat exchanger group and the second water outlet of the fixed tooth heat exchanger group are both connected to the return water pipe parallel to the outside of the cooling bed, each of the radiant heat exchangers is provided with a third water inlet and a third water outlet, the third water inlet is connected to the water supply pipe, the third water outlet is connected to the return water pipe, the return water pipe is connected to the steam drum, the steam in the steam drum is transported to the steam turbine generator, the condensed water of the steam turbine generator is pressurized and returned to the steam drum, and the steam drum transports the condensed water to the water supply pipe.

[0008] Furthermore, the radiant heat heat exchanger is a box structure, and several layers of heat pipes are arranged in the radiant heat heat exchanger. The heat pipes of each layer are connected end to end, and the heat pipes of the upper layer are connected in series with the heat pipes of the lower layer to form a first reflux channel. The third water inlet is arranged at the low-temperature end of the first reflux channel of the upper layer, and the third water outlet is arranged at the low-temperature end of the first reflux channel of the lower layer.

[0009] Furthermore, the fixed-tooth conduction heat heat exchanger is a strip box structure, the second water inlet is provided at the high-temperature end of the fixed-tooth conduction heat heat exchanger in the front row of the fixed-tooth heat exchanger group, the second water outlet is provided at the high-temperature end of the fixed-tooth conduction heat heat exchanger in the last row of the fixed-tooth heat exchanger group, the high-temperature ends of adjacent fixed-tooth conduction heat heat exchangers in the remaining rows of the fixed-tooth heat exchanger group are connected, and the low-temperature ends of adjacent fixed-tooth conduction heat heat exchangers are connected.

[0010] Furthermore, the straightening plate heat conduction heat exchanger includes a straightening plate body, the upper plate surface of the straightening plate body is provided with a straightening groove for straightening rolled steel bars, the lower end of the straightening plate body is provided with a heat collecting cavity, a second reflux channel is provided in the heat collecting cavity, the second reflux channel is arranged around the left and right ends of the straightening groove to form a U-shaped structure, the medium soft water enters the second reflux channel from the low-temperature end of the front end of the straightening groove, and flows out of the second reflux channel from the low-temperature end of the rear end of the straightening groove, the low-temperature end of the straightening plate heat conduction heat exchanger at the front end of the straightening plate heat exchanger group is connected to the water supply pipe; the low-temperature end of the straightening plate heat conduction heat exchanger at the rear end of the straightening plate heat exchanger group is connected to the return water pipe.

[0011] Furthermore, the heat collection chamber is welded on the straightening plate body; and a support seat is provided at the bottom of the heat collection chamber.

[0012] Furthermore, a cantilever hanger is arranged outside the cooling bed, and the radiant heat collector is suspended on the cantilever hanger through a chain.

[0013] Furthermore, a pressure pump is connected to the water supply pipeline, and the pressure pump is used to flow and pressurize the medium soft water in the radiation heat exchanger, the straightening plate conduction heat exchanger and the fixed tooth conduction heat exchanger.

[0014] Furthermore, the cantilever crane includes a pair of columns arranged at intervals, the upper ends of the columns are provided with cantilever beams, and the lower ends of the cantilever beams between the two columns are provided with hydraulic telescopic cylinders; a moving trolley is slidably provided at the lower end of the end of the cantilever beam away from the columns, pulleys are provided on the front and rear ends of the moving trolley, and two chains are provided in the middle of the cantilever beam, and the two chains are respectively passed around the corresponding pulleys and connected to the front and rear ends of the radiant heat heat exchanger; the telescopic end of the hydraulic telescopic cylinder is connected to the moving trolley, and the hydraulic telescopic cylinder is used to push the moving trolley to move axially along the cantilever beam, and the movement of the moving trolley is used to drive the radiant heat heat exchanger to move in a straight line at an angle of 45° with the cantilever beam through the chain.

[0015] Furthermore, the steam drum is connected to the water supply pipeline via a circulation pump.

[0016] Furthermore, it also includes a heating furnace drum, which is connected to the steam turbine generator, and the steam in the heating furnace drum is transported to the steam turbine generator.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] (1) The utility model provides a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars, which fully encloses the cooling bed for heat extraction through the comprehensive arrangement of a radiation heat exchanger, a straightening plate conduction heat exchanger and a fixed tooth conduction heat exchanger. When the rolled steel bar just enters the cooling bed, it is first placed on the straightening plate conduction heat collector for cooling and straightening. At this time, the temperature of the bar is the highest, and the heat is directly transferred to the straightening plate conduction heat collector for heat extraction through the straightening plate conduction heat collector. After the rolled steel bar is straightened and cooled, it is circulated and transferred through the fixed teeth and movable teeth of the cooling bed. Since the movable teeth and the fixed teeth are arranged at intervals, the rolled steel bar moves through the cooperation of the movable and fixed teeth, and a fixed tooth conduction heat collector is arranged between the two sides of the fixed teeth to realize further heat extraction of conduction heat on the surface of the rolled steel bar; the radiation heat collector is arranged above the straightening plate conduction heat collector and the fixed tooth conduction heat collector to realize surface radiation heat extraction of the rolled steel bar. The three-in-one combination of the radiation heat collector, the straightening plate conduction heat collector and the fixed tooth conduction heat collector effectively improves the recovery and utilization of waste heat from the cooling bed.

[0019] (2) The utility model provides a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars. The system is analyzed based on a 180T / h bar line production line (including steam from a heating furnace). The annual operating time is 7,200 hours, and the steam output is: 7,200×15=108,000 tons. This steam is used to generate electricity, then 108,000×110=11,880,000 kWh, which is equivalent to an electricity fee of 6.89 million yuan based on 0.58 yuan / kWh. The carbon reduction is 11,880,000×0.997=10,767 tons, which has a high economic value.

[0020] (3) The utility model provides a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars. The system follows the design concept of a fully enclosed new energy-saving cooling bed. The key to the waste heat of the bar and wire cooling bed is to collect the large amount of heat released by the bars in the cooling process on the cooling bed. The utility model adopts a radiation heat collector, a straightening plate conduction heat collector and a fixed tooth conduction heat collector to achieve an advanced heat collection method of fully enclosed coverage from top to bottom in the area where the waste heat release of the cooling bed is relatively concentrated. The radiation heat and conduction heat of this part of the cooling bed are exchanged with medium soft water to generate saturated high-temperature steam. In order to improve the comprehensive utilization rate of the system and reduce the energy loss caused by the temperature drop during the long-distance transmission of steam, the steam is directly transmitted to the steam turbine generator through the steam drum for local power generation, which effectively improves the waste heat recovery efficiency of rolled steel bars.

[0021] (4) The utility model provides a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars. In order to reduce the soft water medium consumption of the system and reduce the operating cost of the system, the soft water medium is recycled in a closed loop through a heat extraction device, a steam drum and a steam turbine generator, making the system more economical to operate. The heat extraction device has a long overall life, small deformation, and is easy to operate and put into and withdrawn from operation. It does not affect the original steel production process and has no effect on the quality of steel. The heat extraction device can be integrated into the factory thermal network or used simultaneously with the steam from the heating furnace. Compared with other power generation methods, there is no fuel cost, the heat source is relatively concentrated, the carbon reduction effect is obvious, and the system operation is economical and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The utility model is a structural schematic diagram of a waste heat recovery and power generation system of a fully enclosed cooling bed for rolled steel bars.

[0023] Figure 2 It is a schematic diagram of the arrangement structure of the straightening plate heat exchanger group and the fixed tooth heat exchanger group of the heat extraction device of the utility model.

[0024] Figure 3 The utility model is a schematic diagram of the arrangement structure of the radiation heat collector of the heat extraction device.

[0025] Figure 4 A schematic cross-sectional view of the radiation heat collector of the utility model.

[0026] Figure 5 It is a schematic diagram of the longitudinal cross-sectional structure of the straightening plate heat conduction heat exchanger of the utility model.

[0027] Figure 6 It is a schematic diagram of the transverse cross-sectional structure of the straightening plate heat conduction heat exchanger of the utility model.

[0028] Figure 7 It is a structural schematic diagram of the cantilever crane of the utility model;

[0029] The accompanying drawings are numbered as follows: 1-heat extraction device drum, 2-circulation pump, 3-heat extraction device, 4-heating furnace drum, 5-steam turbine generator, 6-feed water pump, 7-condenser, 8-purging pump, 9-cooling tower, 10-condensation pump, 11-deaerator, 31-straightening plate conduction heat collector, 32-fixed tooth conduction heat collector, 33-radiation heat collector, 34-cantilever crane, 35-water supply pipe, 36-return water pipe, 311-straightening trough, 312-heat collecting cavity, 313-support seat, 314-partition, 315-straightening plate water inlet, 316-straightening plate water outlet, 331-heat extraction box, 332-lifting ear, 333-heat extraction pipe, 341-column, 342-cantilever beam, 343-hydraulic telescopic cylinder, 344-chain, 345-mobile trolley. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0031] like Figure 1-Figure 3 As shown. The utility model provides a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars, comprising a heat extraction device 3 and a steam turbine generator 5, wherein the heat extraction device 3 is connected to the steam turbine generator 5 via a steam drum 1 of the heat extraction device; the heat extraction device 3 comprises a plurality of radiation heat collectors 33, a straightening plate heat collector group and a fixed tooth heat collector group, wherein the straightening plate heat collector group comprises a plurality of straightening plate conduction heat collectors 31 connected end to end in sequence, wherein the straightening plate conduction heat collectors 31 are sequentially arranged at the starting end of the high temperature zone of the cooling bed, wherein the fixed tooth heat collector group comprises a plurality of fixed tooth conduction heat collectors 32 connected end to end in sequence, wherein each fixed tooth conduction heat collector 32 is respectively arranged on both sides of the fixed teeth of the cooling bed, and the radiation heat collectors 33 are sequentially suspended in parallel at the upper end of the rolled steel bars on the cooling bed; the straightening plate The first water inlet of the heat exchanger group and the second water inlet of the fixed tooth heat exchanger group are both connected to the water supply pipe 35 parallel to the outside of the cooling bed, the first water outlet of the straightening plate heat exchanger group and the second water outlet of the fixed tooth heat exchanger group are both connected to the return water pipe 36 parallel to the outside of the cooling bed, and each of the radiation heat exchangers 33 is provided with a third water inlet and a third water outlet, the third water inlet is connected to the water supply pipe 35, and the third water outlet is connected to the return water pipe 36, and the return water pipe 36 is connected to the heat extraction device drum 1, and the steam in the heat extraction device drum 1 is transported to the steam turbine generator 5, and the condensed water of the steam turbine generator 5 is pressurized and returned to the heat extraction device drum 1, and the heat extraction device drum 1 transports the condensed water to the water supply pipe 35.

[0032] Specifically, in order to achieve effective heat collection, the radiation heat collector 33, the straightening plate conduction heat collector 31 and the fixed tooth conduction heat collector 32 fully enclose the cooling bed to collect heat. When the rolled steel bar comes down from the production line, the temperature is as high as about 1000°C. It is first placed in the straightening plate conduction heat collector 31 for cooling and transfer, and then gradually transferred through the moving teeth and fixed teeth of the cooling bed for cooling and finally moved out of the cooling bed. During the movement of the rolled steel bar, the fixed tooth conduction heat collector 32 on the fixed tooth side further absorbs the heat on the surface of the rolled steel bar, and at the same time, the radiation heat on the surface of the rolled steel bar is absorbed by the radiation heat collector 33.

[0033] The straightening plate heat conduction heat exchangers 31 are sequentially arranged along the longitudinal direction of the rolled steel bar, and the front and rear adjacent straightening plate heat conduction heat exchangers 31 are connected in series to form a straightening plate heat exchanger group. The fixed tooth heat conduction heat exchangers 32 are sequentially arranged along the radial direction of the rolled steel bar, and the front and rear adjacent fixed tooth heat conduction heat exchangers 32 are connected to form a fixed tooth heat exchanger group. The radiation heat exchangers 33 are sequentially arranged along the longitudinal direction of the rolled steel bar and suspended. The water supply pipe 35 and the return water pipe 36 are respectively arranged in parallel on the outside of the cooling bed. The first water inlet is set at the front low-temperature end of the first straightening plate heat conduction heat exchanger 31 at the front end of the straightening plate heat exchanger group, and the first water outlet is set at the rear low-temperature end of the last straightening plate heat conduction heat exchanger 31. The rear low-temperature end of the first straightening plate heat conduction heat exchanger 31 is connected to the front low-temperature end of the second straightening plate heat conduction heat exchanger 31, and so on. The straightening plate heat conduction heat exchangers 31 are connected end to end.

[0034] The medium soft water enters the first straightening plate heat conduction heat exchanger 31 from the water supply pipe 35 and then flows out from the last straightening plate heat conduction heat exchanger 31 to bring the heat into the return water pipe 36, and is transported to the steam drum 1 of the heat extraction device by the return water pipe 36.

[0035] Each fixed-tooth conduction heat exchanger 32 is connected in series end to end to form a fixed-tooth heat exchanger group. A second water inlet is set at the high-temperature end of the first row of fixed-tooth conduction heat exchangers in the fixed-tooth heat exchanger group, and a second water outlet is set at the high-temperature end of the last row of fixed-tooth conduction heat exchangers in the fixed-tooth heat exchanger group. The low-temperature end of the first row of fixed-tooth conduction heat exchangers is connected to the low-temperature end of the second row of fixed-tooth conduction heat exchangers, and the high-temperature end of the second row of fixed-tooth conduction heat exchangers is connected to the high-temperature end of the third row of fixed-tooth conduction heat exchangers. The fixed-tooth heat exchanger group is formed in this way.

[0036] The medium soft water enters the first row of fixed tooth conduction heat exchangers 32 from the water supply pipe 35 and then flows out from the last row of fixed tooth conduction heat exchangers 32 to bring the heat into the return water pipe 36, which is then transported to the steam drum 1 of the heat extraction device.

[0037] Each radiant heat heat exchanger 33 is suspended from the upper end of the rolled steel bar. A third water inlet is arranged at the upper low-temperature end of each radiant heat heat exchanger 33, and a third water outlet is arranged at the lower high-temperature end. The third water inlet and the third water outlet are arranged at the same side of the front end of the radiant heat heat exchanger 33.

[0038] The medium soft water enters the third water inlet of each radiant heat heat exchanger 33 from the water supply pipe 35, and after circulating in the radiant heat heat exchanger 33, brings the heat into the return water pipe 36 from the third water outlet of each radiant heat heat exchanger 33, and is transported to the steam drum 1 of the heat extraction device by the return water pipe 36.

[0039] The medium soft water absorbs the radiation heat and conduction heat of the rolled steel bars through the straightening plate heat exchanger group, the fixed tooth heat exchanger group and the radiation heat heat exchanger 33, and then enters the heat extraction device drum 1 through the return water pipe 36. The vapor-liquid separation is carried out in the heat extraction device drum 1 to form high-temperature steam and high-temperature water. The high-temperature steam in the heat extraction device drum 1 is transported to the steam turbine generator 5 for power generation. The condensed water of the steam turbine generator 5 is pressurized and returned to the heat extraction device drum 1. The heat extraction device drum 1 transports the condensed water and the separated high-temperature water to the water supply pipe 35 again for recycling, and the medium soft water forms a closed loop.

[0040] like Figure 4 Further, the radiant heat heat exchanger 33 is a box structure, and a plurality of layers of heat pipes 333 are arranged in the radiant heat heat exchanger 33, and each layer of heat pipes 333 are connected end to end, and the upper layer of heat pipes 333 are connected in series with the lower layer of heat pipes 333 to form a first reflux channel, and the third water inlet is arranged at the low temperature end of the first reflux channel of the upper layer, and the third water outlet is arranged at the low temperature end of the first reflux channel of the lowest layer.

[0041] Specifically, the radiation heat exchanger 33 is a rectangular sealed box structure, and the radiation heat exchanger 33 is welded by metal plates. The radiation heat exchanger 33 includes a heat exchange box 331, and three layers of heat exchange pipes 333 are arranged longitudinally in sequence from top to bottom. In the heat exchange pipes 333 of the first layer at the top, the heat exchange pipes 333 of each layer are sequentially divided into groups of 8-10 pipes side by side to form multiple groups of heat exchange pipes 333, and the multiple groups of heat exchange pipes 333 are sequentially connected end to end to form a first reflux channel.

[0042] In the first layer of heat pipes 333, the heads of the first group of 8-10 heat pipes 333 located at the edge of the low temperature end are connected to form a third water inlet connected to the water supply pipe 35. The tails of the first group of 8-10 heat pipes 333 are connected to the tails of the adjacent second group of 8-10 heat pipes 333, the heads of the second group of 8-10 heat pipes 333 are connected to the heads of the adjacent third group of 8-10 heat pipes 333, and the tails of the third group of 8-10 heat pipes 333 are connected to the tails of the fourth group of 8-10 heat pipes 333. In this way, the heat pipes 333 of the first layer are connected in a surrounding manner.

[0043] The tail ends of the last group of 8-10 heat pipes 333 of the first layer of heat pipes 333 are connected to the tail ends of the last group of 8-10 heat pipes 333 of the middle layer opposite to each other, and the heads of the second to last group of 8-10 heat pipes 333 of the middle layer are connected to the heads of the third to last group of 8-10 heat pipes 333 of the middle layer, and the heat pipes 333 of the middle layer are connected in a circular manner.

[0044] The heat pipes 333 in the middle layer are then connected in the same way as the first and second layers, and the heat pipes 333 in the middle layer are connected in a circumferential manner to the heat pipes 333 in the third layer at the bottom, and finally the tails of the last group of 8-10 heat pipes 333 in the third layer are connected to form a third water outlet connected to the return pipe 36. Each radiant heat collector 33 is connected to the return pipe 36 and the water inlet pipe in this way.

[0045] Each radiant heat collector 33 is provided with hanging ears 332 around the upper end thereof for hanging.

[0046] The medium soft water of the water supply pipe 35 enters the multiple heat pipes 333 from the third water inlet of the upper layer, surrounds the heat pipes 333 of the upper layer, the heat pipes 333 of the middle layer and the heat pipes 333 of the lower layer in turn, and then flows out from the third water outlet into the return water pipe 36.

[0047] Furthermore, the fixed-tooth conduction heat heat exchanger 32 is a strip box structure, the second water inlet is set at the high-temperature end of the front row of the fixed-tooth conduction heat exchanger 32 in the fixed-tooth heat exchanger group, the second water outlet is set at the high-temperature end of the last row of the fixed-tooth conduction heat exchanger 32 in the fixed-tooth heat exchanger group, the high-temperature ends of adjacent fixed-tooth conduction heat exchangers 32 in the remaining rows of the fixed-tooth heat exchanger group are connected, and the low-temperature ends of adjacent fixed-tooth conduction heat exchangers 32 are connected.

[0048] Specifically, since the cooling bed is provided with a number of fixed teeth and movable teeth spaced side by side, the fixed teeth are used to place the movable teeth to further cool the rolled steel bars transported from the straightening plate heat conduction heat exchanger 31, and there is a spacing of about 12-15 cm between a pair of adjacent fixed teeth and movable teeth on the cooling bed, and the heat of the rolled steel bars in this area is still around 600-800°C, and the fixed tooth heat conduction heat exchanger 32 is used to further extract the heat of the rolled steel bars in this area.

[0049] A fixed tooth heat conduction heat exchanger 32 is arranged between the two sides of an adjacent pair of fixed teeth. When the rolled steel bar is placed on the fixed teeth, the lower surface of the rolled steel bar directly adheres to the upper surface of the fixed tooth heat conduction heat exchanger 32 to transfer heat to the medium soft water in the fixed tooth heat conduction heat exchanger 32.

[0050] The fixed-tooth conduction heat exchangers 32 are arranged in a longitudinal arrangement in sequence, and a second water inlet is set at the high-temperature end of the fixed-tooth conduction heat exchangers 32 in the first row. The low-temperature end of the fixed-tooth conduction heat exchangers 32 in the first row is connected to the low-temperature end of the fixed-tooth conduction heat exchangers 32 in the second row through a connecting pipe, and the high-temperature end of the fixed-tooth conduction heat exchangers 32 in the second row is connected to the high-temperature end of the fixed-tooth conduction heat exchangers 32 in the third row through a connecting pipe. All the fixed-tooth conduction heat exchangers 32 are connected in series in sequence to form a fixed-tooth heat exchanger group. The medium soft water enters the second water inlet from the water supply pipe 35, passes through the fixed-tooth conduction heat exchangers 32 in sequence, and flows out from the second water outlet of the last row of fixed-tooth conduction heat exchangers 32 into the return water pipe 36.

[0051] like Figure 5 , Figure 6 As shown. Further, the straightening plate heat conduction heat exchanger 31 comprises a straightening plate body, the upper plate surface of the straightening plate body is provided with a straightening groove 311 for straightening rolled steel bars, the lower end of the straightening plate body is provided with a heat collecting chamber 312, the heat collecting chamber 312 is provided with a second reflux channel, the second reflux channel surrounds the left and right ends of the straightening groove 311 to form a U-shaped structure, the medium soft water enters the second reflux channel from the low temperature end of the front end of the straightening groove 311, and flows out of the second reflux channel from the low temperature end of the rear end of the straightening groove 311, the low temperature end of the straightening plate heat conduction heat exchanger 31 at the front end of the straightening plate heat exchanger group is connected to the water supply pipe 35; the low temperature end of the straightening plate heat conduction heat exchanger 31 at the rear end of the straightening plate heat exchanger group is connected to the return water pipe 36.

[0052] Specifically, the upper plate surface of the straightening plate body is provided with a straightening groove 311, and the lower plate surface is provided with a heat collecting cavity 312, and the heat collecting cavity 312 is filled with medium soft water for collecting heat. The straightening plate body can realize the straightening function and the heat collecting function without affecting the original installation method, thereby realizing the waste heat recovery of the rolled steel bar.

[0053] In the straightening plate heat exchanger group, the front and rear ends of the front and rear adjacent straightening plate heat conduction heat exchangers 31 are connected in series through a connecting pipe to form a straightening plate heat exchanger group. A first water inlet is set at the front low-temperature end of the second return channel 14 of the first straightening plate heat conduction heat exchanger 31, and a first water outlet is set at the rear low-temperature end of the second return channel 14 of the last straightening plate heat conduction heat exchanger 31. The first water inlet is connected to the water supply pipe 35, and the first water outlet is connected to the return water pipe 36.

[0054] The low-temperature end at the rear end of the first straightening plate heat conduction heat exchanger 31 is connected to the low-temperature end at the front end of the second straightening plate heat conduction heat exchanger 31 through a connecting pipe, and the low-temperature end at the rear end of the second straightening plate heat conduction heat exchanger 31 is connected to the low-temperature end at the front end of the third straightening plate heat conduction heat exchanger 31 through a connecting pipe, and so on, and the low-temperature end at the front end of the last straightening plate heat conduction heat exchanger 31 is connected through a connecting pipe.

[0055] The conductive heat of the rolled steel bar is transferred to the heat collecting cavity 312 of each straightening plate conductive heat extractor 31 and is then heat exchanged by the medium soft water through the second return channel 14 and then brought into the return water pipe 36 .

[0056] The heat collection cavity 312 is arranged on the lower plate surface of the straightening plate body and is an integrated structure with the straightening plate body. The heat collection cavity 312 is a cavity box structure. The upper surface of the heat collection cavity 312 is the lower surface of the straightening plate body. The lower shape of the heat collection cavity 312 is set according to the shape of the straightening plate body. The space on the lower surface of the straightening plate body is surrounded and connected to form the heat collection cavity 312. The outer periphery of the heat collection cavity 312 is not larger than the outer periphery of the straightening plate body.

[0057] A partition 314 is disposed in the heat collecting chamber 312 . The partition 314 is disposed longitudinally along the heat collecting chamber 312 . The partition 314 is perpendicular to the bottom surface of the heat collecting chamber 312 . The direction of the partition 314 is perpendicular to the direction of the straightening groove 311 .

[0058] The partition 314 is arranged at the longitudinal center of the heat collecting chamber 312 to divide the heat collecting chamber 312 into two chambers, wherein one end of the partition 314 is sealedly connected to the low-temperature end of the heat collecting chamber, and the other end of the partition 314 is separated from the high-temperature end of the heat collecting chamber 312 to form a second reflux channel, so that the medium soft water refluxes at the high-temperature end.

[0059] A straightening plate water inlet 315 and a straightening plate water outlet 316 are respectively provided at the front and rear end bottoms of the second reflux channel 14 of each heat collecting chamber 312. The straightening plate water inlet 315 of the first straightening plate heat conduction heat exchanger 31 serves as the first water inlet, the straightening plate water outlet 316 of the last straightening plate heat conduction heat exchanger 31 serves as the first water outlet, and the straightening plate water outlets 316 of the remaining adjacent straightening plate heat conduction heat exchangers 31 are connected to the straightening plate water inlet 315.

[0060] The partition 314 is vertically arranged in the heat collection chamber 312 to divide the heat collection chamber into two parts. The upper and lower ends of the partition are closed and connected to the upper and lower inner wall surfaces of the heat collection chamber 312. The partition 314 leaves a medium channel at the high-temperature end of the heat collection chamber 312 to form a gap with the high-temperature end of the heat collection chamber.

[0061] Furthermore, the heat collection chamber 312 is welded on the straightening plate body; a support seat 313 is provided at the bottom of the heat collection chamber 312 .

[0062] Specifically, the straightening plate body is made of cast iron, cast steel or wear-resistant steel plate by pressing and welding. At the same time, the heat collecting chamber 312 is welded to be integrated with the straightening plate body. In order to facilitate the support of the entire straightening plate, support seats 313 are provided on both sides of the bottom of the heat collecting chamber 312, and the support seats 313 are respectively arranged longitudinally along the bottom of the heat collecting chamber 312.

[0063] Furthermore, a cantilever hanger 344 is provided on the outer side of the cooling bed, and the radiant heat collector 33 is suspended on the cantilever hanger 34 through a chain 344 .

[0064] Specifically, in order to suspend the radiant heat heat exchanger 33, a cantilever hanger 344 is arranged on the outer side of the straightening plate conductive heat exchanger 31, and the upper end of the cantilever hanger 344 extends to the outermost end of the fixed tooth conductive heat exchanger 32. A chain 344 is arranged on the extended end of the cantilever hanger 344 to suspend the radiant heat heat exchanger 33, and the horizontal position and vertical height of the radiant heat heat exchanger 33 can be adjusted by adjusting the length of the chain 344.

[0065] Furthermore, a pressure pump is connected to the first water inlet 33 , and the pressure pump is used to flow and pressurize the medium soft water in the radiation heat exchanger 33 , the straightening plate conduction heat exchanger 31 and the fixed tooth conduction heat exchanger 32 .

[0066] In order to increase the flow of the medium soft water, a pressure pump is arranged on the first water inlet 33, and the pressure pump can further increase the flow rate of the medium soft water.

[0067] like Figure 7 As shown. Further, the cantilever 34 comprises a pair of columns 341 arranged at intervals, the upper ends of the columns 341 are provided with cantilever beams 342, and the lower ends of the cantilever beams 342 between the two columns 341 are provided with hydraulic telescopic cylinders 343; a moving trolley 345 is slidably provided at the lower end of the end of the cantilever beam 342 away from the columns 341, and pulleys are provided at both the front and rear ends of the moving trolley 345, and two chains 344 are provided in the middle of the cantilever beam 342, and the two chains 344 are respectively connected to the front and rear ends of the radiant heat heat extractor 33 by bypassing the corresponding pulleys; the telescopic end of the hydraulic telescopic cylinder 343 is connected to the moving trolley 345, and the hydraulic telescopic cylinder 343 is used to push the moving trolley to move axially along the cantilever beam 342, and the movement of the moving trolley 345 is used to drive the radiant heat heat extractor 33 to move linearly at an angle of 45° with the cantilever beam 342 through the chains 344.

[0068] Specifically, in the utility model, the cantilever hanger 34 includes two groups of axially spaced pairs of columns 341 arranged outside the cooling bed, each pair of columns 341 is arranged along the radial direction of the rolled steel bar, each pair of columns 341 is arranged at intervals, and the upper end of each pair of columns 341 supports a cantilever beam 342, one end of the cantilever beam 342 is fixed on a pair of columns 341, and the other end of the cantilever beam 342 extends to one side of the rolled steel bar in the cooling bed, and a hydraulic telescopic cylinder 343 is arranged at the lower end of the cantilever beam 342 between the two columns 341, and the telescopic end of the hydraulic telescopic cylinder 343 passes through the column 341 on one side and then extends toward one side of the fixed tooth heat conduction heat exchanger 32, and the lower ends of the pair of cantilever beams 342 located on one side of the rolled steel bar slide through rollers. The movable trolley 345 is connected, and the telescopic end of each hydraulic telescopic cylinder 343 is hinged with the movable trolley 345. The hydraulic telescopic cylinder 343 can drive the movable trolley 345 to move axially along a pair of cantilever beams 342. A pair of laterally spaced pulleys are respectively provided at the front and rear ends of the movable trolley 345. A pair of chains 344 are respectively provided at the lower end of the cantilever beam 342 between each hydraulic telescopic cylinder 343 and the movable trolley 345. The pair of chains 344 are spaced apart from each other, and one end of each pair of chains 344 is fixed on the cantilever beam 342. The other ends of the pair of chains 344 are respectively turned through the pulleys at the front and rear ends of the movable trolley 345 and then pass through the movable trolley 345 to be connected to the hanging ear 332 of the radiant heat heat collector 33.

[0069] When a pair of hydraulic telescopic cylinders 343 move synchronously, the moving trolley 345 moves axially along the cantilever beam 342. At this time, the radiant heat heat exchanger 33 is driven to move by the chain 344 to adjust the distance and position between the radiant heat heat exchanger 33 and the rolled steel bar. When the radiant heat heat exchanger 33 moves, it moves obliquely up and down along a straight line at an angle of 45° to the cantilever beam 342.

[0070] Again Figure 1 As shown. Further, the steam drum 1 of the heat extraction device is connected to the water supply pipeline 35 through the circulating pump 2. In order to transport the condensed water in the steam drum 1 of the heat extraction device to the water supply pipeline 35 to form a closed loop, the steam drum 1 of the heat extraction device is connected to the water supply pipeline 35 through the circulating pump 2. The steam turbine generator 5 is connected to the steam drum 1 of the heat extraction device after being connected in series with the condenser 7, the condensation pump 10, the deaerator 11 and the feed water pump 6 in sequence. The condenser 7 is also connected to the cooling tower 9 through the clean ring pump 8.

[0071] The steam drum 1 of the heat extraction device is the key equipment for steam-water separation in the system. The working temperature of the steam drum 1 of the heat extraction device is 178°C, the working pressure is 0.8MPa, and the steam separation is higher than 15t / h.

[0072] In the system of the utility model, the deaerator 11 is used to remove oxygen in the circulating water to avoid damage to the system equipment. The working pressure of the deaerator 11 is 0.02MPa.

[0073] Circulation pump 2 is used to provide stable pressure and flow rate for the system. Circulation pump 2, flow rate Q = 70m3 / h, head h = 80m.

[0074] The cooling tower 9 is used to cool the condenser 7. The cooling tower 9 uses water as a circulating coolant to discharge the absorbed heat into the atmosphere to reduce the water temperature. This system uses a countercurrent glass fiber reinforced plastic water cooling tower with a cooling tower flow rate of Q = 900m3 / h, a temperature difference of 10°C, a water collection tray, a water pressure at the bottom of the tower of no more than 0.1MPa, and a cooling fan power of P = 37kW.

[0075] The clean ring pump 8 is used to provide cooling water for the condenser 7. This system adopts a single-stage double-suction split-type centrifugal clean ring pump with a flow rate of Q=900m3 / h, a head of 47m, and a motor power of 160kW.

[0076] The 6 groups of feed water pumps are used to replenish water to the drum 1 of the heat extraction device to ensure the stability of the water level of the drum 1 of the heat extraction device. This system uses two sets of feed water pumps, with a single flow rate of Q=12m3 / h and a head of h=110m.

[0077] The steam turbine generator 5 is a condensing steam turbine. The performance of the steam turbine generator 5 complies with the provisions of GB5578-85, and adopts a constant pressure operation mode, which can adapt to the changes of steam parameters.

[0078] Furthermore, it also includes a heating furnace drum 4, which is connected to the steam turbine generator 5, and the steam of the heating furnace drum 4 is transported to the steam turbine generator 5 to generate electricity.

[0079] Specifically, a heating furnace steam drum 4 is arranged in the heating furnace vaporization system for heating steel billets during the steel rolling process of the steel mill. In order to effectively utilize the steam in the heating furnace steam drum 4 of the steel rolling mill, the heating furnace steam drum 4 is simultaneously connected to a steam turbine generator 5. The steam in the heating furnace steam drum 4 is mixed with the steam in the steam drum 1 of the cooling bed waste heat recovery device and then transported to the steam turbine generator 5, thereby further effectively utilizing the steam in the heating furnace steam drum 4 of the steel mill.

Claims

1. A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars. It is characterized in that The invention comprises a heat extraction device and a steam turbine generator (5), wherein the heat extraction device is connected to the steam turbine generator (5) via a steam drum (1); the heat extraction device comprises a plurality of radiation heat extractors (33), a straightening plate heat extractor group and a fixed tooth heat extractor group, wherein the straightening plate heat extractor group comprises a plurality of straightening plate conduction heat extractors (31) connected end to end in sequence, wherein the straightening plate conduction heat extractors (31) are sequentially arranged at the starting end of the high temperature zone of the cooling bed, and the fixed tooth heat extractor group comprises a plurality of fixed tooth conduction heat extractors (32) connected end to end in sequence, wherein each fixed tooth conduction heat extractor (32) is respectively arranged at two sides of the fixed teeth of the cooling bed, and the radiation heat extractors (33) are sequentially suspended in parallel at the upper end of the rolled steel bar on the cooling bed; the first water inlet of the straightening plate heat extractor group and the fixed tooth The second water inlet of the heat exchanger group is connected to a water supply pipe (35) parallel to the outside of the cooling bed, the first water outlet of the straightening plate heat exchanger group and the second water outlet of the fixed tooth heat exchanger group are connected to a return water pipe (36) parallel to the outside of the cooling bed, and each of the radiation heat exchangers (33) is provided with a third water inlet and a third water outlet, the third water inlet is connected to the water supply pipe (35), and the third water outlet is connected to the return water pipe (36), the return water pipe (36) is connected to the steam drum (1), the steam in the steam drum (1) is transported to the steam turbine generator (5), the condensed water of the steam turbine generator (5) is pressurized and then returned to the steam drum (1), and the steam drum (1) transports the condensed water to the water supply pipe (35).

2. According to claim 1, a waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars, It is characterized in that The radiant heat heat exchanger (33) is a box structure, and a plurality of layers of heat pipes (333) are arranged in the radiant heat heat exchanger (33), the heat pipes (333) of each layer are connected end to end, the heat pipes (333) of the upper layer are connected in series with the heat pipes (333) of the lower layer to form a first reflux channel, the third water inlet is arranged at the low-temperature end of the first reflux channel of the upper layer, and the third water outlet is arranged at the low-temperature end of the first reflux channel of the lower layer.

3. A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars according to claim 1 or 2, It is characterized in that The fixed-tooth conduction heat exchanger (32) is a strip-shaped box structure; the second water inlet is provided at the high-temperature end of the front row of the fixed-tooth conduction heat exchanger (32) of the fixed-tooth heat exchanger group; the second water outlet is provided at the high-temperature end of the last row of the fixed-tooth conduction heat exchanger (32) of the fixed-tooth heat exchanger group; the high-temperature ends of adjacent fixed-tooth conduction heat exchangers (32) in the remaining rows of the fixed-tooth heat exchanger group are connected, and the low-temperature ends of adjacent fixed-tooth conduction heat exchangers (32) are connected.

4. A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars according to claim 3, It is characterized in that The straightening plate heat conduction heat exchanger (31) comprises a straightening plate body, the upper plate surface of the straightening plate body is provided with a straightening groove (311) for straightening rolled steel bars, the lower end of the straightening plate body is provided with a heat collecting chamber (312), a second reflux channel is provided in the heat collecting chamber (312), the second reflux channel is arranged around the left and right ends of the straightening groove (311) to form a U-shaped structure, the medium soft water enters the second reflux channel from the low temperature end of the front end of the straightening groove (311), and flows out of the second reflux channel from the low temperature end of the rear end of the straightening groove (311), the low temperature end of the straightening plate heat conduction heat exchanger (31) at the front end of the straightening plate heat exchanger group is connected to the water supply pipe (35), and the low temperature end of the straightening plate heat conduction heat exchanger (31) at the rear end of the straightening plate heat exchanger group is connected to the return water pipe (36).

5. A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars according to claim 4, It is characterized in that The heat collection chamber (312) is welded to the straightening plate body; and a support seat (313) is provided at the bottom of the heat collection chamber (312).

6. The waste heat recovery and power generation system of a fully enclosed cooling bed for rolled steel bars according to claim 1, It is characterized in that A cantilever hanger (34) is arranged outside the cooling bed, and the radiant heat heat extractor (33) is suspended on the cantilever hanger (34) through a chain (344).

7. The waste heat recovery and power generation system of the fully enclosed cooling bed for rolled steel bars according to claim 5, It is characterized in that The water supply pipe (35) is connected to a pressure pump, and the pressure pump is used to flow and pressurize the medium soft water in the radiation heat exchanger (33), the straightening plate conduction heat exchanger (31) and the fixed tooth conduction heat exchanger (32).

8. The waste heat recovery and power generation system of the fully enclosed cooling bed for rolled steel bars according to claim 6, It is characterized in that The cantilever crane (34) comprises a pair of columns (341) arranged at intervals, a cantilever beam (342) is arranged at the upper end of the column (341), and a hydraulic telescopic cylinder (343) is arranged at the lower end of the cantilever beam (342) between the two columns (341); a moving trolley (345) is slidably arranged at the lower end of the end of the cantilever beam (342) away from the column (341), pulleys are arranged on the front and rear ends of the moving trolley (345), and two chains (343) are arranged in the middle of the cantilever beam (342). 4), the two chains (344) are respectively passed around the corresponding pulleys and are respectively connected to the front and rear ends of the radiant heat heat exchanger (33); the telescopic end of the hydraulic telescopic cylinder (343) is connected to the moving trolley (345), the hydraulic telescopic cylinder (343) is used to push the moving trolley to move axially along the cantilever beam (342), and the movement of the moving trolley (345) is used to drive the radiant heat heat exchanger (33) and the cantilever beam (342) to move in a straight line at an angle of 45° through the chain (344).

9. The waste heat recovery and power generation system of a fully enclosed cooling bed for rolled steel bars according to claim 1, It is characterized in that The steam drum (1) is connected to the water supply pipeline (35) via a circulation pump (2).

10. A waste heat recovery and power generation system for a fully enclosed cooling bed for rolled steel bars according to claim 9, It is characterized in that It also comprises a heating furnace drum (4), wherein the heating furnace drum (4) is connected to the steam turbine generator (5), and the steam in the heating furnace drum (4) is transported to the steam turbine generator (5).

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