Modularized corrosion-resistant steam pressure stabilizing device for hazardous waste heat

Abstract

The utility model discloses a modularized anti-corrosion steam pressure stabilizing device for hazardous waste heat. The modularized anti-corrosion steam pressure stabilizing device comprises a boiler body, a boiler barrel, a steam pressure stabilizing module and an anti-corrosion module. A first channel and a second channel are arranged in the boiler body, the first channel and the second channel are connected through an ash hopper, a flue gas inlet and a flue gas outlet are formed in the boiler body, the flue gas inlet is connected with the first channel, and the flue gas outlet is connected with the second channel; the boiler barrel is located above the boiler body and connected with the lower collecting box through the centralized descending pipe. Compared with the prior art, the utility model has the advantages that the corrosion resistance is improved, the chromium-nickel alloy layer can tolerate flue gas with the Cl concentration of less than or equal to 5%, and the service life is prolonged by 2-3 times; the steam pressure is stable, and the buffer tank and the fuzzy PID control enable the pressure to fluctuate lt; the pressure is + / -0.05 MPa; ash is efficiently removed, and the spiral channel and the inclined flow guide plate enable the ash sliding efficiency to be improved; due to the modular design, the boiler body and the buffer tank can be transported in a split mode, and the on-site assembly period is shortened by 50%.

Description

TECHNICAL FIELD

[0001] The utility model relates to a dangerous waste heat recovery technical field, specifically relates to a modularization anticorrosion steam pressure stabilizing device, especially suitable for the efficient recovery and steam stable output of high temperature corrosive flue gas waste heat. BACKGROUND

[0002] With the development of industry, the demand for hazardous waste (HW) treatment is increasing, and incineration is one of the current mainstream hazardous waste treatment technologies. In the incineration process, the high-temperature flue gas (usually 800-1000℃) generated by the combustion of hazardous waste contains a large amount of waste heat. If it can be effectively recovered, it can significantly improve energy efficiency and reduce operating costs. Therefore, waste heat boilers (WHB) are widely used in hazardous waste incineration systems to recover flue gas heat and generate steam for power generation or process use.

[0003] However, the composition of hazardous waste incineration flue gas is complex, usually containing high concentrations of acidic gases (such as HCl, SO2), heavy metals and particulate matter. These substances cause serious corrosion to the metal components of the waste heat boiler (such as water-cooled walls, superheaters, economizers, etc.) at high temperatures. In addition, due to the large fluctuations in hazardous waste combustion conditions, the flue gas heat load is unstable, resulting in fluctuations in the boiler steam pressure, affecting the stable operation of the subsequent process.

[0004] In the prior art, some improvements have been made to address the above problems, but there are still the following shortcomings:

[0005] Insufficient corrosion resistance: traditional waste heat boilers are usually made of ordinary carbon steel or low alloy steel. Although some equipment may use surface spray corrosion-resistant coatings (such as ceramic coatings or aluminizing treatment), the coating is prone to peeling in a long-term high-temperature acidic flue gas environment, leading to corrosion and perforation of the substrate and affecting the service life of the equipment. Some high-end equipment uses stainless steel or nickel-based alloy materials, but the cost is high, and the welding process is complex, making it difficult to be widely used.

[0006] Large steam pressure fluctuations: The flue gas heat load of hazardous waste incineration changes rapidly, and traditional boilers rely on mechanical safety valves or simple PID control to regulate the steam pressure, with a slow response speed (> 500ms), making it difficult to adapt to dynamic conditions, resulting in a large range of steam pressure fluctuations (±0.1MPa or more), affecting the stable operation of subsequent generator sets or process equipment. Some systems use external pressure stabilizing tanks, but the structure is complex, and the steam flow field uniformity problem is not considered, resulting in limited pressure stabilization effect.

[0007] Ash and clogging problem: the waste incineration flue gas contains a large amount of fly ash and sticky particles, the traditional waste heat boiler adopts a straight pipe heat exchange structure, the ash hopper is not reasonably designed, and is easy to accumulate ash and clog, thereby reducing the heat exchange efficiency and increasing the maintenance cost. The existing ash removal methods (such as shock wave soot blowing and mechanical vibration) have low reliability in a high-temperature corrosion environment and are easy to damage the equipment.

[0008] Low degree of modularity and difficult maintenance: the traditional waste heat boiler is mostly of an integral structure, transportation and installation are difficult, the on-site welding workload is large, and the construction period is long. After the damage of key components (such as the corrosion-resistant layer and the heat exchange pipe), it is difficult to replace locally, and the whole machine needs to be stopped for maintenance, which affects the production efficiency.

[0009] In view of the above problems, although the existing technology has proposed various improvement schemes (such as optimizing materials, adding a buffer tank, and improving the ash removal device), there is still a lack of a highly integrated, strong corrosion-resistant, steam pressure stable and easy-to-maintain hazardous waste heat recovery device.

[0010] Therefore, a new modular design is needed to ensure efficient heat exchange while improving equipment reliability and operational stability. Practical new type content

[0011] The purpose of the present application is to solve the problems mentioned in the background art, and to provide a hazardous waste heat recovery device with strong corrosion resistance, stable steam pressure, compact structure and easy maintenance.

[0012] To solve the above technical problems, the technical scheme provided by the present application is: a modular corrosion-resistant steam pressure stabilizing device for hazardous waste heat, comprising a boiler body, a boiler drum, a steam pressure stabilizing module and a corrosion-resistant module.

[0013] The first channel and the second channel are connected by an ash hopper, and the boiler body is provided with a flue gas inlet and a flue gas outlet, the flue gas inlet is connected to the first channel, and the flue gas outlet is connected to the second channel; a lower header is arranged at the bottom of the boiler body, and a membrane water cooling wall is arranged inside the boiler body, and the water cooling pipe of the membrane water cooling wall is connected to the lower header;

[0014] The boiler drum is located above the boiler body, and the boiler drum is connected to the lower header through a central downcomer;

[0015] The steam pressure stabilizing module comprises a steam buffer tank, the steam buffer tank is arranged between the boiler body and the boiler drum, and is connected by a steam pipeline, and the steam buffer tank is provided with a pressure sensor, a pressure regulating valve and a controller;

[0016] The corrosion-resistant module comprises a corrosion-resistant layer arranged on the inner wall of the membrane water cooling wall.

[0017] As a preferred solution, the first channel and the second channel are arranged in a spiral shape, and the helix angle is 30° to 45°.

[0018] As a preferred solution, the ash hopper is provided with an inclined guide plate, the guide plate is at an angle of 50° to 60° with the horizontal plane, and the bottom is provided with a vibrating ash discharge valve.

[0019] As a preferred solution, the steam buffer tank is provided with staggered porous baffles, the opening rate of the baffle is 30%-40%, and the top of the tank body is provided with a double safety relief valve.

[0020] As a preferred solution, the corrosion-resistant layer is chromium-nickel alloy, and the thickness is 0.8-1.5mm.

[0021] As a preferred solution, the controller is connected with a flue gas analyzer and a temperature sensor, and the control algorithm adopts fuzzy PID control, and the response time is less than 200ms.

[0022] The utility model discloses compared with prior art has the advantages of: the corrosion resistance is promoted, the chromium-nickel alloy layer can bear the flue gas of Cl- concentration ≤5%, and the life is prolonged 2-3 times, the steam pressure is stable, and the pressure fluctuation is less than ±0.05MPa under the buffer tank and fuzzy PID control, high -efficient ash removal, and the spiral channel + inclined guide plate makes the ash slide off efficiency to improve, modular design, and the boiler body and buffer tank can be split and transport, and the on -the -spot assembly cycle is shortened 50%. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is the structural schematic diagram of the utility model.

[0024] Figure 2 It is the schematic diagram of the first channel / second channel spiral arrangement of the utility model.

[0025] Figure 3 It is the section view of the corrosion-resistant layer and the membrane water cooled wall of the utility model.

[0026] As shown in the figure: 1, boiler body, 2, boiler drum, 3, first channel, 4, second channel, 5, ash hopper, 6, flue gas inlet, 7, flue gas outlet, 8, lower header, 9, membrane water cooled wall, 10, concentrated downcomer, 11, steam buffer tank, 12, steam pipeline, 13, pressure sensor, 14, pressure regulating valve, 15, controller, 16, corrosion-resistant layer. DETAILED DESCRIPTION

[0027] The technical solutions of the present application will be clearly and completely described below with reference to the drawings, obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0028] In the description of the present application, it should be pointed out that the directions or position relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back" are based on the directions or position relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limitations on the present application in terms of the specific directions, the specific directions of construction and operation. Therefore, it cannot be understood as a limitation on the present application. In addition, "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present application, it should be pointed out that unless otherwise explicitly specified and limited, the terms "mounting", "connecting" and "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected. It can be mechanically connected, or it can be point connected. It can be directly connected, or indirectly connected through an intermediate medium. It can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0030] In combination with the drawings, a modular corrosion-resistant steam pressure stabilizing device for hazardous waste waste heat comprises a boiler body 1, a boiler drum 2, a steam pressure stabilizing module and a corrosion-resistant module;

[0031] The first channel 3 and the second channel 4 are connected through the ash chute 5, the boiler body 1 is provided with a flue gas inlet 6 and a flue gas outlet 7, the flue gas inlet 6 is connected with the first channel 3, and the flue gas outlet 7 is connected with the second channel 4; The lower header 8 is arranged at the bottom of the boiler body 1, and the membrane water cooling wall 9 is arranged in the boiler body 1, and the water cooling pipe of the membrane water cooling wall 9 is connected with the lower header 8;

[0032] The boiler drum 2 is located above the boiler body 1, and the boiler drum 2 is connected with the lower header 8 through the central downcomer 10;

[0033] The steam pressure stabilizing module comprises a steam buffer tank 11, the steam buffer tank 11 is arranged between the boiler body 1 and the boiler drum 2, and is connected through a steam pipeline 12, the steam buffer tank 11 is provided with a pressure sensor 13, a pressure regulating valve 14 and a controller 15;

[0034] The anticorrosion module comprises an anticorrosion layer 16 arranged on the inner wall of the membrane water wall 9.

[0035] The first channel 3 and the second channel 4 are arranged in a spiral shape, and the spiral angle is 30-45°.

[0036] The ash hopper 5 is provided with an inclined guide plate, the guide plate forms an angle of 50-60° with the horizontal plane, and the bottom is provided with a vibrating ash discharge valve.

[0037] The steam buffer tank 11 is provided with staggered arranged perforated baffles, the opening rate of the baffles is 30-40%, and the top of the tank body is provided with a double safety relief valve.

[0038] The anticorrosion layer 16 is chromium-nickel alloy, and the thickness is 0.8-1.5mm.

[0039] The controller 15 is connected with a flue gas analyzer and a temperature sensor, and the control algorithm adopts a fuzzy PID control, and the response time is less than 200ms.

[0040] In the specific implementation, the first channel and the second channel in the boiler body are made of 316L stainless steel, the spiral angle is 35°, the total length is increased by 1.8 times compared with a straight pipe, and the heat exchange is strengthened; the ash hopper is provided with an inclined guide plate at an angle of 55°, and a vibrating ash discharge valve (frequency 10Hz, amplitude 2mm) is installed at the bottom to prevent ash accumulation.

[0041] The tank body of the steam buffer tank is made of Q345R, the opening rate of the internal baffles is 35%, the staggered interval is 200mm, the steam flow rate is reduced to below 1.5m / s, the set pressure of the double safety valve is 1.1 times of the design value, and the pressure is relieved redundantly.

[0042] The controller receives signals of a flue gas analyzer (monitoring SO2 and HCl concentrations) and a temperature sensor (accuracy ±1℃), and dynamically adjusts the opening degree of the pressure regulating valve through a fuzzy PID algorithm.

[0043] Operation method and working principle

[0044] Flue gas process: high-temperature flue gas (800-1000℃) enters the first channel from the flue gas inlet, is cooled to 500℃ through spiral heat exchange, and then enters the ash hopper; the ash and slag slide down the guide plate to the ash discharge valve, and the purified flue gas enters the second channel for further heat exchange to below 200℃, and is discharged from the flue gas outlet.

[0045] Water vapor circulation: saturated water in the drum enters the lower header through the central downcomer, absorbs heat through the membrane water wall to form a steam-water mixture, and returns to the drum for separation; saturated steam enters the buffer tank, is uniformly distributed through the baffles, and is output to the user end.

[0046] Pressure stabilization control: when the steam pressure is detected to be out of limit, the controller adjusts the opening degree of the pressure regulating valve within 150ms to maintain constant pressure.

[0047] Embodiment

[0048] Take the hazardous waste incineration line with a processing capacity of 10 t / h as an example:

[0049] The boiler body diameter is 2.5 m, the first passage length is 80 m, the second passage length is 60 m, and the steam buffer tank volume is 8 m 3 , the design pressure is 4.0 MPa, the operation data are that the steam pressure fluctuation is ±0.03 MPa, the annual corrosion rate is less than 0.1 mm, and the ash unloading period is prolonged to 72 h.

[0050] The above describes the utility model and its embodiments, which are not limited, and the drawings only show one of the embodiments of the utility model, and the actual structure is not limited thereto. In summary, if a person skilled in the art is inspired, without departing from the creative purpose of the utility model, similar structure modes and embodiments are not creatively designed, which should belong to the protection scope of the utility model.

Claims

1. A modular corrosion resistant steam pressure stabilizing device for hazardous waste heat, characterized by: The boiler body, the boiler drum, the steam pressure stabilizing module and the anticorrosion module are included. The first channel and the second channel are arranged inside the boiler body, and the first channel is connected with the second channel through the ash chute. The boiler drum is arranged above the boiler body, and is connected with the lower header through the central downcomer. The steam pressure stabilizing module includes the steam buffer tank, which is arranged between the boiler body and the boiler drum, and is connected through the steam pipeline. The anticorrosion module includes the anticorrosion layer arranged on the inner wall of the membrane water cooling wall.

2. A modular corrosion resistant steam pressure stabilizing device for hazardous waste heat according to claim 1, characterized in that: The first channel and the second channel are arranged in a spiral shape, and the spiral angle is 30° to 45°.

3. A modular corrosion resistant steam pressure stabilizing device for hazardous waste heat according to claim 1, wherein: The ash chute is provided with the inclined guide plate, which is arranged at an angle of 50° to 60° with the horizontal plane, and is provided with the vibrating ash discharge valve at the bottom.

4. The modular corrosion resistant steam pressure stabilizing device for hazardous waste heat according to claim 1, characterized in that: The steam buffer tank is provided with the staggered perforated baffles, and the opening rate of the baffles is 30% to 40%, and the tank body is provided with the double safety relief valve at the top.

5. The modular corrosion resistant steam pressure stabilizing device for hazardous waste heat according to claim 1, wherein: The anticorrosion layer is the chromium-nickel alloy, and the thickness is 0.8 to 1.5 mm.

6. A modular corrosion resistant steam pressure stabilizing device for hazardous waste heat according to claim 1, wherein: The controller is connected with the flue gas analyzer and the temperature sensor, and the control algorithm adopts the fuzzy PID control, and the response time is less than 200 ms.

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