Crushing turn-off device with waste heat recycling function and dry slag system

Abstract

The invention discloses a crushing turn-off device with a waste heat recycling function and a dry slag system. The crushing turn-off device comprises a mounting frame, a driving device, a crushing device and a circulating water pipeline, and the crushing device comprises two rows of extrusion heads which are oppositely arranged; the circulating water pipeline comprises a plurality of cooling water pipes, a water inlet end and a water return end, the cooling water pipes are arranged below the crushing device, one ends of the cooling water pipes are connected to the water inlet end, the other ends of the cooling water pipes are connected to the water return end, and a water pump is arranged between the water inlet end and the water return end. The slag drying system further comprises a slag well, a slag drying machine, a control system and the like. The circulating water pipeline is arranged in the breaking turn-off device, heat absorption of slag is achieved, recycled waste heat is further utilized, and the heat utilization rate is increased; and meanwhile, water cooling and air cooling are combined, so that the dry slag system better adapts to different working condition requirements, the air inlet rate of the dry slag system can be accurately controlled, and the boiler efficiency is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of coal-fired boiler slag removal equipment, and in particular to a crushing and shutting-off device with a waste heat recycling function and a dry slag system. Background Art

[0002] At present, most coal-fired boilers use air-cooled dry slag removal systems. The system uses ambient air to cool the slag at about 800°C falling from the boiler furnace. The cooling air is heated to 250-400°C hot air (not lower than the hot air temperature of the boiler secondary air) and enters the furnace from the bottom throat of the boiler. Under normal operating conditions of the unit, when the air intake rate (the ratio of the air intake of the dry slag system to the total combustion air volume of the boiler) is less than 1% to 1.5%, it has a positive effect on the boiler efficiency. The external air intake of the air-cooled dry slag removal system is partly automatically controlled and partly manually controlled. When the slag volume is large, the air intake cannot fully cool the slag, resulting in unsatisfactory slag cooling temperature; when the slag volume is small, the air intake rate becomes larger (some dampers are manually controlled, which is inconvenient for frequent operation), which has a negative impact on boiler combustion. The air-cooled dry slag discharge system is equipped with a crushing and shut-off device. The slag usually needs to be crushed by the crushing and shut-off device before entering the dry slag discharger. The existing crushing device only plays the role of crushing and shutting off the slag, with a single function and cannot play a positive role in cooling the slag. Summary of the invention

[0003] Purpose of the invention: In view of the shortcomings of the existing crushing and shut-off devices that have a single function and cannot play a positive role in cooling the slag, the present invention provides a crushing and shut-off device and a dry slag system with waste heat recovery function, which can cool the slag, reduce the workload of the air cooling system, and recycle the waste heat.

[0004] Technical solution: To solve the above problems, the present invention adopts a crushing shut-off device with waste heat recycling function, including a mounting frame, a driving device, a crushing device, and a circulating water pipeline. The crushing device includes two rows of extrusion heads arranged opposite to each other, and the driving device is connected to the extrusion heads to drive the two rows of extrusion heads to move closer to or away from each other; the circulating water pipeline includes a plurality of cooling water pipes, a water inlet end, and a return water end. The cooling water pipe is arranged below the crushing device, one end of the cooling water pipe is connected to the water inlet end, and the other end of the cooling water pipe is connected to the return water end, and a water pump is arranged between the water inlet end and the return water end.

[0005] Furthermore, it also includes a grille guide tube installed on the mounting frame, the grille guide tube is hollow inside, and the cooling water pipe is installed in the grille guide tube.

[0006] Furthermore, the cooling water pipes are arranged in parallel with each other, and both ends of each water pipe are connected to a water inlet end and a water return end.

[0007] Furthermore, both ends of the cooling water pipe extend out of the mounting frame, and the water inlet end, the water return end, and the water pump are all located outside the mounting frame.

[0008] Furthermore, the water inlet and water return ends are both provided with monitoring devices for monitoring water temperature, water pressure and water flow.

[0009] Furthermore, the driving device is hydraulically driven.

[0010] Beneficial effect: Compared with the prior art, the present invention realizes heat absorption of slag by setting a circulating water pipeline in the crushing shut-off device, further utilizes the recovered waste heat, and improves the heat utilization rate.

[0011] The present invention also provides a dry slag system including a crushing shut-off device, which also includes a slag pit, a dry slag machine, and a control system. The crushing shut-off device is installed between the slag pit and the dry slag machine. The dry slag machine is provided with an intelligent air intake system, and the intelligent air intake system and the circulating water pipeline are jointly controlled by the control system.

[0012] Furthermore, the intelligent air inlet system includes a first air inlet pipeline arranged on both sides of the dry slag machine and a second air inlet pipeline arranged on the top of the dry slag machine.

[0013] Furthermore, the air inlets of the first air inlet pipeline and the second air inlet pipeline are both provided with air volume regulating devices.

[0014] Furthermore, the intelligent air intake system is provided with a monitoring device for monitoring the air intake temperature information and air intake speed in the dry slag machine.

[0015] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) the dry slag system cooperates with the intelligent air intake system through the circulating water pipeline to cool the slag, thereby reducing the workload of the air intake system; the automatic control method is adopted, which makes the control of air volume and circulating water more flexible and better adapts to different working conditions. The air intake rate can be accurately controlled to effectively improve the boiler efficiency; (2) the combination of water cooling and air cooling is conducive to maintaining the activity of dry slag, and the condensed water that absorbs the heat of the slag can be reused to participate in the work of the steam turbine, or used for heating or domestic water. The intelligent air intake device can bring the heat of the slag into the furnace to participate in the boiler combustion, so that the waste heat of the slag can be fully utilized, with significant economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front view of the crushing and shutting-off device of the present invention;

[0017] Figure 2 It is a side view of the crushing and shutting-off device of the present invention;

[0018] Figure 3 It is a top view of the crushing and shutting-off device of the present invention;

[0019] Figure 4 This is a schematic diagram of the distribution of the circulating water pipeline of the present invention;

[0020] Figure 5 This is a schematic diagram of the overall structure of the dry slag system of the present invention;

[0021] Figure 6 It is a side view of the dry slag system of the present invention. DETAILED DESCRIPTION

[0022] Embodiment 1

[0023] like Figures 1 to 3 As shown, in this embodiment, a crushing shut-off device with a waste heat recycling function includes a mounting frame 1, a hydraulic drive device 2, a crushing device 3, a circulating water pipeline 4, and a grille guide pipe 5. The mounting frame 1 includes a supporting leg and a mounting box located on the top of the supporting leg, and the hydraulic drive device 2 is fixedly installed on both sides of the mounting box. The crushing device 3 includes two rows of extrusion heads 31 arranged opposite to each other, and the hydraulic drive device 2 is connected to the extrusion head 31 to drive the two rows of extrusion heads 3 to move closer to or away from each other. The circulating water pipeline 4 includes a plurality of cooling water pipes 41, a water inlet end 6, and a water return end 7 arranged parallel to each other. The grille guide pipe 5 is fixedly installed in the mounting box, the grille guide pipe 5 is hollow inside, and the cooling water pipe 41 is installed in the grille guide pipe 5. The cooling water pipe 41 is arranged below the crushing device 3, and both ends of the cooling water pipe 41 extend out of the mounting box, as shown in FIG. Figure 4 As shown, one end of the cooling water pipe 41 is connected to the water inlet end 6, and the other end is connected to the water return end 7. A water pump 8 is arranged between the water inlet end and the water return end. The water inlet end 6, the water return end 7, and the water pump 8 are all located outside the installation box. The water inlet end 6 and the water return end 7 are both provided with monitoring devices for monitoring water temperature, water pressure, and water flow.

[0024] The crushing shutoff device of this embodiment drives the extrusion heads 31 to move closer or farther from each other through the hydraulic drive device 2. When the extrusion heads 31 move closer to each other, the slag falling from the slag pit can be squeezed and crushed. When the extrusion heads 31 move farther from each other, the slag falls from the slag pit to the steel belt of the slag dryer. When the extrusion head 31 moves to the middle position and stops, the extrusion head 31 realizes the shutoff door function, so that the slag cannot fall from the slag pit to the slag dryer. Steam turbine condensate is introduced into the circulating water pipeline 4 to cool and recover the crushed slag, absorb the surface heat of the hot slag falling from the furnace, and the heated condensate is reused to participate in the work of the steam turbine. It can also be used for heating or domestic water, improve the heat utilization rate, and realize the comprehensive utilization of the waste heat of the dry slag. The circulating water pipeline 4 can be remotely and automatically controlled by the monitoring device set at the water inlet and return ends.

[0025] Embodiment 2

[0026] like Figure 5 and Figure 6As shown, this embodiment provides a dry slag system including the above-mentioned crushing and shutting-off device, and also includes a slag pit 9, a dry slag machine 10 and a control system. The crushing and shutting-off device is installed between the slag pit 9 and the dry slag machine 10. The dry slag machine is provided with an intelligent air intake system, and the intelligent air intake system and the circulating water pipeline 4 are jointly controlled by the control system. The intelligent air intake system includes a first air intake pipeline 101 arranged on both sides of the dry slag machine 10 and a second air intake pipeline 102 arranged on the top of the dry slag machine 10. The air inlets of the first air intake pipeline 101 and the second air intake pipeline 102 are both provided with an air volume regulating device 103. The intelligent air intake system is also provided with a monitoring device for monitoring the temperature information and air intake speed in the dry slag machine. The control system automatically controls and adjusts the water inlet amount, water outlet temperature, air door opening and air volume adjustment through the monitoring data of the monitoring equipment installed in the circulating water pipeline 4 and the intelligent air inlet system, combined with boiler data such as furnace load, coal powder amount entering the furnace, total furnace air inlet amount, furnace oxygen content, slag discharge system air inlet temperature, slag discharge amount, slag discharge temperature, etc.

[0027] The operating parameters of the dry slag system in this embodiment are as follows: the size of the boiler slag throat is 21.248mx1.2432m, the slag is 8.88t / h, the bulk density is 0.9t / m3, the slag temperature is 900℃, the slag at the outlet of the dry slag machine is 100℃, and the shell temperature of the dry slag machine is 50℃; the furnace outlet pressure of the designed coal type is -0.15kPa, the air volume of the BMCR working condition is 1852.15t / h, the air volume of the dry slag machine is converted into the boiler leakage volume ≤1%, and the air inlet temperature is not less than the secondary air inlet temperature; the length of the dry slag machine is 62m, the width of the machine body is 2.2m, the width of the conveyor belt is 1.4m, and the conveying speed is 0.4-4m / min; the annual operation hours are 8000 hours. The diameter of the cooling water pipe is DN120, and a total of 28 pipes are arranged, and the length of the water pipe facing the bottom of the boiler is 1.5m. It is estimated that each 660MW unit can save 1,833 tons of standard coal per year under rated load conditions, which is 1.46 million yuan at 800 yuan per ton. The additional cost is about 900,000 yuan per unit, and the return on investment is relatively high. According to statistics from the National Energy Administration, by the end of 2023, my country will have 1.16 billion kWh of coal-fired power units in operation, equivalent to 1,757 660MW units, or 1,160 1000MW units. The market prospects are broad and have promotion value.

[0028] The dry slag system of this embodiment cooperates with the intelligent air intake system through the circulating water pipeline to cool the slag, thereby reducing the workload of the air intake system; the automatic control method is adopted, and the control of the air volume and circulating water is more flexible, which can better adapt to the requirements of different working conditions, and the air intake rate can be accurately controlled to effectively improve the boiler efficiency; at the same time, the combination of water cooling and air cooling is conducive to maintaining the activity of dry slag, and the condensed water that absorbs the heat of the slag can be reused to participate in the work of the steam turbine, or used for heating or domestic water. The intelligent air intake device can bring the heat of the slag into the furnace to participate in the boiler combustion, so that the waste heat of the slag is fully utilized, and the economic and social benefits are significant.

Claims

1. A crushing and shutting device with waste heat recycling function, characterized in that: The invention comprises a mounting frame (1), a driving device (2), a crushing device (3), and a circulating water pipeline (4); the crushing device (3) comprises two rows of extrusion heads (31) arranged opposite to each other; the driving device (2) is connected to the extrusion heads (31) to drive the two rows of extrusion heads (31) to move closer to or farther from each other; the circulating water pipeline (4) comprises a plurality of cooling water pipes (41), a water inlet end (6), and a water return end (7); the cooling water pipe (41) is arranged below the crushing device (3); one end of the cooling water pipe (41) is connected to the water inlet end (6), and the other end of the cooling water pipe (41) is connected to the water return end (7); a water pump (8) is arranged between the water inlet end and the water return end.

2. The crushing and shutting-off device according to claim 1, characterized in that: It also includes a grille guide tube (5) installed on the mounting frame (1), wherein the grille guide tube (5) is hollow inside, and a cooling water pipe (41) is installed inside the grille guide tube (5).

3. The crushing and shutting device according to claim 1 or 2, characterized in that: The cooling water pipes (41) are arranged in parallel with each other, and both ends of each water pipe are connected to a water inlet end (6) and a water return end (7).

4. The crushing and shutting-off device according to claim 3, characterized in that: Both ends of the cooling water pipe (41) extend out of the mounting frame (1), and the water inlet end (6), the water return end (7), and the water pump (8) are all located outside the mounting frame (1).

5. The crushing and shutting-off device according to claim 4, characterized in that: The water inlet end (6) and the water return end (7) are both provided with monitoring devices for monitoring water temperature, water pressure and water flow.

6. The crushing and shutting-off device according to claim 1, characterized in that: The driving device (2) is hydraulically driven.

7. A dry slag system comprising the crushing and shut-off device according to any one of claims 1 to 6, characterized in that: It also comprises a slag pit (9), a slag dryer (10), and a control system. The crushing shutoff device is installed between the slag pit (9) and the slag dryer (10). The slag dryer (10) is provided with an intelligent air intake system. The intelligent air intake system and the circulating water pipeline (4) are jointly controlled by the control system.

8. The dry slag system according to claim 7, characterized in that: The intelligent air intake system comprises a first air intake pipeline (101) arranged on both sides of the slag dryer (10) and a second air intake pipeline (102) arranged on the top of the slag dryer (10).

9. The dry slag system according to claim 8, characterized in that: Air volume adjustment devices (103) are provided at the air inlets of the first air inlet pipeline (101) and the second air inlet pipeline (102).

10. The dry slag system according to claim 7, characterized in that: The intelligent air intake system is provided with a monitoring device for monitoring the air intake temperature information and air intake speed in the dry slag machine.

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