SCR flue gas monitoring device

Abstract

The utility model relates to the technical field of denitration, in particular to an SCR (Selective Catalytic Reduction) flue gas monitoring device which comprises a barrel body, a flue gas inlet is formed in one end of the barrel body, a flue gas outlet is formed in the other end of the barrel body, a plurality of groups of conical catalyst layers are arranged in the barrel body, ammonia spraying layers are arranged at the upper parts of the catalyst layers, and each group of ammonia spraying layers are respectively communicated with an ammonia storage tank through pipelines; a flow regulating valve is respectively arranged in a pipeline for communicating each group of ammonia spraying layers with the ammonia storage tank, the plurality of flow regulating valves are electrically connected with the controller, an inlet temperature sensor is arranged at the smoke inlet, an outlet temperature sensor is arranged at the smoke outlet, and the inlet temperature sensor and the outlet temperature sensor are respectively and electrically connected with the controller. By arranging multiple groups of ammonia spraying layers and catalyst layers to be matched with corresponding flow adjusting valves, gradient adjustment of the ammonia spraying amount can be achieved, and waste caused by too large ammonia escape concentration is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to a denitration technical field especially relates to a kind of SCR flue gas monitoring device. BACKGROUND

[0002] Ultra-low emission has become the rigid index of new construction and reconstruction coal-fired generating unit in nationwide, and the concentration of atmospheric pollutant discharged by the coal-fired generating unit after reconstruction basically reaches the emission limit value of gas turbine unit (wherein the emission requirement of nitrogen oxide is not higher than 50mg / m³, and the environmental protection control requirement in local area is not higher than 15mg / m³), which puts forward higher requirement to the control precision and stability of reactor outlet NOx emission.

[0003] At present, in the process of tracking denitration outlet NOx concentration by ammonia injection control of most domestic boilers, due to the existence of large time delay in monitoring inlet NOx concentration and control of controlled object of SCR denitration system, low measurement accuracy of flue gas flow, the control effect of outlet NOx concentration is poor and NOx concentration fluctuates repeatedly, which leads to large consumption of reducing agent ammonia in denitration daily operation and long-term high operation cost; local ammonia escape concentration is too large, which causes damage to air preheater and seriously affects the safety and economy of unit. UTILITARY MODEL

[0004] The technical problem to be solved by the utility model is to provide a kind of SCR flue gas monitoring device, which realizes gradient adjustment of ammonia injection amount by adopting multiple groups of ammonia injection layer and catalyst layer matched with corresponding flow regulating valve, to solve the problem of waste caused by too large ammonia escape concentration.

[0005] To solve the above technical problems, the technical scheme adopted by the utility model is as follows: a kind of SCR flue gas monitoring device, including cylinder, the one end of cylinder is equipped with smoke inlet, the other end is equipped with smoke outlet, the inside of cylinder is equipped with multiple groups of conical catalyst layer, the upper portion of catalyst layer is equipped with ammonia injection layer, each group of ammonia injection layer is communicated with ammonia storage tank by pipeline respectively, the pipeline that each group of ammonia injection layer is communicated with ammonia storage tank is equipped with flow regulating valve respectively, multiple flow regulating valves are electrically connected with controller, inlet temperature sensor is arranged at smoke inlet, outlet temperature sensor is arranged at smoke outlet, inlet temperature sensor and outlet temperature sensor are electrically connected with controller respectively.

[0006] Further optimize the technical scheme, the bottom of cylinder is equipped with conical barrel part, the bottom of conical barrel part is equipped with collection box, the axis of conical barrel part is equipped with downwardly open smoke exhaust pipe, the top of smoke exhaust pipe is communicated with smoke outlet.

[0007] Further optimize the technical scheme, the side of inlet temperature sensor is also equipped with inlet flow sensor, the side of outlet temperature sensor is equipped with outlet flow sensor, outlet flow sensor and outlet flow sensor are electrically connected with controller respectively.

[0008] Further optimize the technical scheme, the outlet of the ammonia storage tank is provided with a flow monitoring device, and the flow monitoring device is electrically connected with the controller.

[0009] Further optimize the technical scheme, the lower side of the cylinder body is provided with a catalyst consolidation layer, and the catalyst consolidation layer is arranged on the lower side of the catalyst layer.

[0010] Further optimize the technical scheme, the top of the ammonia injection layer is fixed on the lower side of the rectifier grid.

[0011] Compared with the prior art, the utility model has the following advantages: 1, through setting up multiple groups of ammonia injection layer and catalyst layer cooperation corresponding flow regulating valve can realize the gradient adjustment of ammonia injection amount, avoid the waste caused by too large ammonia escape concentration;2, through the inlet temperature sensor cooperation inlet flow sensor multidimensional monitoring of the flue gas entering amount change situation of the flue gas inlet, through the outlet temperature sensor cooperation outlet flow sensor multidimensional monitoring of the flue gas exhaust amount change situation of the flue gas outlet, can provide the control signal of ammonia injection amount for the controller in time, the judgment of controller is more timely and accurate;3, through setting up the catalyst layer to be conical can further improve the residence time of ammonia water in catalyst layer, improve the reaction efficiency, the influence of flue gas circulation is small;4, through the setting of the collecting box cooperation opening downward exhaust pipe realizes the preliminary collection of smoke dust particles, avoids the particulate matter with the flue gas after processing into the preheater to a certain extent, guarantees the use effect of preheater. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a kind of SCR flue gas monitoring device's principle schematic diagram.

[0013] In the drawing: 1, cylinder body;10, conical barrel part;101, collecting box;11, flue inlet;12, flue outlet;120, exhaust pipe;13, inlet temperature sensor;14, outlet temperature sensor;2, catalyst layer;20, catalyst consolidation layer;3, ammonia injection layer;31, rectifier grid;4, ammonia storage tank;41, flow regulating valve;42, flow monitoring device;5, controller;6, preheater;7, boiler. DETAILED DESCRIPTION

[0014] To make the purpose, technical scheme and advantage of the utility model more clear and obvious, the utility model is further explained in detail below with reference to the specific embodiment of the attached drawings.It should be understood that these descriptions are only exemplary, and are not intended to limit the scope of the utility model.In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the utility model.

[0015] It should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like involved in the present application indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure. In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0016] In combination Figure 1 As shown, an SCR flue gas monitoring device includes a cylinder 1, the top end of the cylinder 1 is provided with a smoke inlet 11, the smoke inlet 11 is connected with the smoke outlet of the boiler 7, the other end of the lower side is provided with a smoke outlet 12, the inside of the cylinder 1 is provided with a plurality of groups of conical catalyst layers 2, the thickness of the catalyst layer 2 is uniformly arranged, and the catalyst layer 2 is provided with a vanadium-titanium SCR catalyst. The upper part of the catalyst layer 2 is provided with an ammonia injection layer 3, and the top of the ammonia injection layer 3 is fixed to the lower side of the rectifier grid 31. Each group of ammonia injection layers 3 is respectively communicated with an ammonia storage tank 4 through a pipeline, and a flow regulating valve 41 is respectively arranged in the pipeline communicated with the ammonia storage tank 4 of each group of ammonia injection layers 3. A plurality of flow regulating valves 41 are electrically connected with a controller 5, and a flow monitoring device 42 is arranged at the outlet of the ammonia storage tank 4, and the flow monitoring device 42 is electrically connected with the controller 5.

[0017] An inlet temperature sensor 13 is arranged at the smoke inlet 11, and an outlet temperature sensor 14 is arranged at the smoke outlet 12. The inlet temperature sensor 13 and the outlet temperature sensor 14 are respectively electrically connected with the controller 5. An inlet flow sensor is further arranged on one side of the inlet temperature sensor 13, and an outlet flow sensor is arranged on one side of the outlet temperature sensor 14. The outlet flow sensor and the outlet flow sensor are respectively electrically connected with the controller 5.

[0018] The lower side of the cylinder 1 is provided with a catalyst consolidation layer 20, and the catalyst consolidation layer 20 is arranged on the lower side of the catalyst layer 2. The bottom of the cylinder 1 is provided with a conical barrel part 10, and the bottom of the conical barrel part 10 is provided with a collection box 101. A downwardly open smoke exhaust pipe 120 is arranged at the axis of the conical barrel part 10, and the top of the smoke exhaust pipe 120 is communicated with the smoke outlet 12.

[0019] In use, in combination Figure 1As shown, the inlet temperature sensor 13 is arranged to cooperate with the inlet flow sensor to monitor the change of the flue gas entering amount at the flue gas inlet 11, the outlet temperature sensor 14 is arranged to cooperate with the outlet flow sensor to monitor the change of the flue gas discharging amount at the flue gas outlet 12, the controller 5 can be provided with the control signal of the ammonia injection amount in time, the multiple groups of ammonia injection layers 3 and catalyst layers 2 are arranged to cooperate with the corresponding flow regulating valves 41 to realize the gradient adjustment of the ammonia injection amount, and the waste caused by the too large ammonia escape concentration is further avoided.

[0020] The controller 5 is more timely and accurate, the catalyst layer 2 is arranged to be conical to further improve the residence time of the ammonia water in the catalyst layer 2 and improve the reaction efficiency, the influence on the flue gas circulation is small, the collecting box 101 is arranged to cooperate with the downwardly opening flue gas discharge pipe 120 to realize the preliminary collection of the dust particles, the particles are avoided from entering the preheater 6 along with the treated flue gas to a certain extent, and the use effect of the preheater 6 is ensured.

[0021] The control mode of the utility model is automatically controlled through the controller, the control circuit of the controller can be realized through simple programming of the person skilled in the art, and the control mode and the circuit connection are common knowledge in the field, so the utility model will not be explained in detail.

[0022] Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all the other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.

Claims

1. An SCR flue gas monitoring device comprising a cylinder (1), one end of the cylinder (1) is provided with a flue gas inlet (11), the other end is provided with a flue gas outlet (12), characterized in that: The inside of the cylinder (1) is provided with a plurality of groups of conical catalyst layers (2), the upper part of the catalyst layer (2) is provided with an ammonia injection layer (3), each group of the ammonia injection layer (3) is communicated with an ammonia storage tank (4) through a pipeline, respectively, a flow regulating valve (41) is arranged in the pipeline of each group of the ammonia injection layer (3) and the ammonia storage tank (4), a plurality of the flow regulating valves (41) are electrically connected with a controller (5), an inlet temperature sensor (13) is arranged at the smoke inlet (11), an outlet temperature sensor (14) is arranged at the smoke outlet (12), and the inlet temperature sensor (13) and the outlet temperature sensor (14) are electrically connected with the controller (5), respectively.

2. An SCR flue gas monitoring device according to claim 1, characterised in that: The bottom of the cylinder (1) is provided with a conical barrel part (10), the bottom of the conical barrel part (10) is provided with a collection box (101), the axis of the conical barrel part (10) is provided with a downwardly open smoke exhaust pipe (120), and the top of the smoke exhaust pipe (120) is communicated with the smoke outlet (12).

3. The SCR flue gas monitoring device of claim 1, wherein: The inlet temperature sensor (13) is further provided with an inlet flow sensor on one side, the outlet temperature sensor (14) is provided with an outlet flow sensor on one side, and the outlet flow sensor and the outlet flow sensor are electrically connected with the controller (5), respectively.

4. The SCR flue gas monitoring device of claim 1, wherein: The outlet of the ammonia storage tank (4) is provided with a flow monitoring device (42), and the flow monitoring device (42) is electrically connected with the controller (5).

5. The SCR flue gas monitoring device of claim 1, wherein: The lower side of the cylinder (1) is provided with a catalyst consolidation layer (20), and the catalyst consolidation layer (20) is arranged on the lower side of the catalyst layer (2).

6. The SCR flue gas monitoring device of claim 1, wherein: The top of the ammonia injection layer (3) is fixed on the lower side of the rectifier grid (31).

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