A urea direct injection pyrolysis spray gun characteristic test device and method

Abstract

The invention discloses an experimental device and method for testing the characteristics of a urea direct injection pyrolysis spray gun. The middle part of the dual-fluid urea direct injection pyrolysis spray gun is installed inside a tubular heater; the outlet of the blower is connected to the inlet of the hot air gun via a first manual valve, and the outlet of the hot air gun is connected to the hot air inlet of the tubular heater; the outlet of the water tank is connected to the liquid pipeline inlet of the dual-fluid urea direct injection pyrolysis spray gun via a gear pump; the outlet of the air compressor is divided into two paths after filtering and reducing the pressure, one of which is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun via a second manual valve, and the other is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun via a third manual valve. The device and method can simulate and realize the test of the characteristics of a urea direct current pyrolysis spray gun.

Description

Technical Field

[0001] This invention relates to a testing apparatus and method, specifically to a testing apparatus and method for the characteristics of a urea direct injection pyrolysis spray gun. Background Technology

[0002] Gas-fired combined cycle (Gas-fired Steam Cycle) power generation technology has been widely applied in my country due to its clean and efficient characteristics. In recent years, with the tightening of national environmental standards, many regions have imposed stricter requirements on NOx emissions from gas turbines. Under these circumstances, SCR (Selective Catalytic Reduction) denitrification technology is needed to ensure NOx emissions meet standards. Common reducing agents used in SCR denitrification technology include liquid ammonia, ammonia water, and urea. Among these, urea has received widespread attention due to its high safety, ease of transportation, and storage. In gas-fired Steam Cycle units, urea direct injection pyrolysis technology has attracted scholarly attention due to its simple system, low energy consumption, and ease of operation and maintenance.

[0003] The urea direct injection pyrolysis technology in gas-fired combined cycle turbine units involves placing urea direct injection pyrolysis nozzles in the transition flue gas duct at the gas turbine outlet. The heat from the high-temperature flue gas is used to pyrolyze the atomized urea droplets. To ensure uniform mixing of the urea pyrolysis products with NOx in the flue gas, the urea direct injection pyrolysis nozzles typically need to extend into the flue gas duct. For units of Class E and above, the diameter of the gas turbine outlet flue gas duct is usually large, and the longest distance the nozzle extends into the flue gas duct can reach 2-3 meters. On the other hand, because the initial NOx level of the gas turbine is low, the urea solution flow rate of a single nozzle is small, resulting in a urea solution flow velocity inside the nozzle typically below 0.1 m / s. Therefore, the nozzle faces the risk of the urea solution being evaporated by the high temperature during its internal flow in the high-temperature flue gas environment, thus clogging the nozzle.

[0004] In this context, the structure and characteristic parameters of the spray gun are particularly important for the successful application of urea direct injection pyrolysis technology. However, conducting characteristic tests on the spray gun in actual units is costly. Therefore, an experimental setup is needed to simulate the operating conditions of gas turbine exhaust in a combined cycle gas turbine unit to conduct experimental research on the structure and characteristic parameters of the spray gun. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an experimental device and method for testing the characteristics of a urea direct injection pyrolysis spray gun. This device and method can simulate and test the characteristics of a urea direct injection pyrolysis spray gun.

[0006] To achieve the above objectives, the experimental apparatus for testing the characteristics of urea direct injection pyrolysis spray gun according to the present invention includes a dual-fluid urea direct injection pyrolysis spray gun, a tubular heater, a blower, a hot air gun, a water tank, a gear pump, an air compressor, a filter pressure reducer, a first manual valve, a second manual valve, and a third manual valve.

[0007] The middle part of the dual-fluid urea direct injection pyrolysis spray gun is installed inside the tubular heater;

[0008] The outlet of the blower is connected to the inlet of the hot air gun via the first manual valve, and the outlet of the hot air gun is connected to the hot air inlet of the tubular heater.

[0009] The outlet of the water tank is connected to the liquid pipeline inlet of the dual-fluid urea direct injection pyrolysis spray gun via a gear pump;

[0010] The outlet of the air compressor is divided into two paths after passing through the filter and pressure reducer. One path is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun via the second manual valve, and the other path is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun via the third manual valve.

[0011] The outlet of the blower is connected to the inlet of the hot air gun via the first manual valve and the first float flow meter, and the outlet of the hot air gun is connected to the hot air inlet of the tubular heater.

[0012] The outlet of the water tank is connected to the liquid pipeline inlet of the dual-fluid urea direct injection pyrolysis spray gun via a gear pump and a first pressure gauge.

[0013] The outlet of the air compressor is divided into two paths after passing through the filter and pressure reducer. One path is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun via the second manual valve, the second float flow meter and the second pressure gauge. The other path is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun via the third manual valve and the third float flow meter.

[0014] The tubular heater includes a round steel pipe and a connecting pipe, wherein the end of the connecting pipe is connected to the side of the tail of the round steel pipe, the tail of the round steel pipe is closed, a hot air gun is inserted into the connecting pipe, a high-temperature electric heating wire is wound around the outer wall of the round steel pipe, and a heat insulation cotton layer is wrapped around the outer wall of the round steel pipe. The middle part of the dual-fluid urea direct injection pyrolysis spray gun is sleeved inside the round steel pipe.

[0015] The heating power of the hot air gun is adjustable.

[0016] A steel plate layer is installed on the outside of the insulation cotton layer.

[0017] The middle part of the dual-fluid urea direct injection pyrolysis spray gun is installed inside the tubular heater via a flange.

[0018] The experimental method for testing the characteristics of urea direct injection pyrolysis spray gun according to the present invention includes the following steps:

[0019] Turn on the air compressor, filter pressure reducer, second manual valve, and third manual valve to send cooling air and atomizing air into the dual-fluid urea direct injection pyrolysis spray gun; turn on the blower and first manual valve to send air into the hot air gun. After being heated by the hot air gun, the air enters the round steel pipe. Power is applied to the electric heating wire, and the outlet air temperature of the round steel pipe is measured. When the outlet air temperature of the round steel pipe reaches the preset range, the gear pump is turned on to introduce liquid into the dual-fluid urea direct injection pyrolysis spray gun. The liquid is atomized by the atomizing air and then sprayed out.

[0020] The present invention has the following beneficial effects:

[0021] In the specific operation of the urea direct injection pyrolysis spray gun characteristic testing experimental device and method described in this invention, air is sent to a hot air gun by a blower, heated, and then sent to a tubular heater. The tubular heater simulates a high-temperature flue gas environment, and the temperature of the flue gas is adjustable. Water is adjusted to the required flow rate and pressure by a gear pump and then sent to the dual-fluid urea direct injection pyrolysis spray gun. Air is adjusted to the required flow rate and pressure by an air compressor, filter pressure reducer, and manual valve, and then sent to the dual-fluid urea direct injection pyrolysis spray gun as atomizing air and cooling air, respectively, to test the thermal insulation performance of the dual-fluid urea direct injection pyrolysis spray gun in a simulated high-temperature flue gas environment. The system can be adjusted to meet engineering needs and features a simple system, adjustable parameters, and high reliability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention.

[0023] Among them, 1 is a dual-fluid urea direct injection pyrolysis spray gun, 2 is a tubular heater, 3 is a blower, 4 is a hot air gun, 51 is a first manual valve, 52 is a second manual valve, 53 is a third manual valve, 61 is a first float flow meter, 62 is a second float flow meter, 63 is a third float flow meter, 7 is a filter pressure reducer, 8 is an air compressor, 9 is a water tank, 10 is a gear pump, 111 is a first pressure gauge, and 112 is a second pressure gauge. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, not all embodiments, and are not intended to limit the scope of the present invention. Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion regarding the concepts disclosed in the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0025] The accompanying drawings show structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not drawn to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0026] refer to Figure 1 The experimental apparatus for testing the characteristics of a urea direct injection pyrolysis spray gun according to the present invention includes a dual-fluid urea direct injection pyrolysis spray gun 1, a tubular heater 2, a blower 3, a hot air gun 4, a first manual valve 51, a second manual valve 52, a third manual valve 53, a first float flowmeter 61, a second float flowmeter 62, a third float flowmeter 63, a filter pressure reducer 7, an air compressor 8, a water tank 9, a gear pump 10, a first pressure gauge 111, and a second pressure gauge 112;

[0027] The middle part of the dual-fluid urea direct injection pyrolysis spray gun 1 is installed inside the tubular heater 2 via a flange;

[0028] The outlet of blower 3 is connected to the inlet of hot air gun 4 via the first manual valve 51 and the first float flow meter 61. The outlet of hot air gun 4 is connected to the hot air inlet of tubular heater 2.

[0029] The outlet of water tank 9 is connected to the liquid pipeline inlet of dual-fluid urea direct injection pyrolysis spray gun 1 via gear pump 10 and first pressure gauge 111. The liquid pressure entering dual-fluid urea direct injection pyrolysis spray gun 1 is measured by the first pressure gauge 111.

[0030] The outlet of the air compressor 8 is divided into two paths after passing through the filter pressure reducer 7. One path is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun 1 via the second manual valve 52, the second float flow meter 62 and the second pressure gauge 112. The other path is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun 1 via the third manual valve 53 and the third float flow meter 63, serving as the cooling air for the dual-fluid urea direct injection pyrolysis spray gun 1.

[0031] The tubular heater 2 includes a round steel pipe and a connecting pipe. The end of the connecting pipe is connected to the side of the tail of the round steel pipe, and the tail of the round steel pipe is closed. The hot air gun 4 is inserted into the connecting pipe. A high-temperature electric heating wire is wound around the outer wall of the round steel pipe, and a heat insulation cotton layer is wrapped around the outer wall of the round steel pipe. A steel plate layer is set on the outside of the heat insulation cotton layer. The heating power of the hot air gun 4 is adjustable. At the same time, the heating effect of the electric heating wire and the heat insulation effect of the heat insulation cotton layer are combined to maintain the internal temperature of the round steel pipe within a preset range. The middle part of the dual-fluid urea direct injection pyrolysis spray gun 1 is sleeved inside the round steel pipe.

[0032] The main purpose of this invention is to provide an environment that simulates actual high-temperature flue gas, so as to conduct experiments on the thermal insulation performance of the dual-fluid urea direct injection pyrolysis spray gun 1.

[0033] The experimental method for testing the characteristics of urea direct injection pyrolysis spray gun according to the present invention includes the following steps:

[0034] Turn on the air compressor 8, filter pressure reducer 7, second manual valve 52, and third manual valve 53 to send cooling air and atomizing air into the dual-fluid urea direct injection pyrolysis spray gun 1; turn on the blower 3 and first manual valve 51 to send air into the hot air gun 4. After being heated by the hot air gun 4, the air enters the round steel pipe. Power is applied to the electric heating wire, and the outlet air temperature of the round steel pipe is measured. When the outlet air temperature of the round steel pipe reaches the preset range, turn on the gear pump 10 to introduce liquid into the dual-fluid urea direct injection pyrolysis spray gun 1. The liquid is atomized by the atomizing air and sprayed out.

[0035] During the experiment, the pressure of the atomizing air was adjusted by adjusting the filter pressure reducer 7, and the flow rate of the cooling air entering the dual-fluid urea direct injection pyrolysis spray gun 1 was adjusted by adjusting the third manual valve 53.

[0036] The airflow into the hot air gun 4 is adjusted to the preset value by the first manual valve 51, and then the power switch of the hot air gun 4 is turned on and the temperature of the hot air gun 4 is set. At this time, the air enters the round steel pipe after being heated by the hot air gun 4.

[0037] After the temperature of the cooling air sprayed from the dual-fluid urea direct injection pyrolysis spray gun 1 stabilizes, observe the atomization effect of the dual-fluid urea direct injection pyrolysis spray gun 1 and measure the temperature of the cooling air at the same time.

[0038] The principle of this invention is as follows: Air is sent to a hot air gun 4 via a blower 3, heated, and then fed into a tubular heater 2. The tubular heater 2 has an electric heating wire and an insulation layer on its round steel pipe. Through the heating function of the hot air gun 4, the heating of the electric heating wire, and the insulation of the insulation layer, a high-temperature flue gas environment is simulated. Simultaneously, the flow rate and temperature of the high-temperature flue gas are adjustable. On the other hand, water is adjusted to the required flow rate and pressure by a gear pump 10 and then fed into the dual-fluid urea direct injection pyrolysis nozzle 1. An air compressor 8, a filter pressure reducer 7, a second manual valve 52, and a third manual valve 53 feed atomized air and cooling air into the dual-fluid urea direct injection pyrolysis nozzle 1. The flow rate of the cooling air entering the dual-fluid urea direct injection pyrolysis nozzle 1 is independently adjustable, as are the pressure and flow rate of the atomized air entering the dual-fluid urea direct injection pyrolysis nozzle 1.

[0039] It should be noted that this invention can simulate a high-temperature flue gas environment and adjust the flow rate and temperature of the high-temperature flue gas. At the same time, it can adjust the cooling air flow rate, atomizing air pressure, and water flow rate entering the dual-fluid urea direct injection pyrolysis spray gun 1, thereby testing the thermal insulation performance of the dual-fluid urea direct injection pyrolysis spray gun 1 in a high-temperature flue gas environment, and making improvements as needed, thereby designing a dual-fluid urea direct injection pyrolysis spray gun 1 that meets the needs of different engineering application scenarios. The system of this invention is simple, the parameters are adjustable, and the reliability is high, which can provide technical support for engineering implementation.

Claims

1. A urea direct injection pyrolysis spray gun characteristic test device, characterized in that: It comprises a dual-fluid urea direct injection pyrolysis spray gun (1), a tubular heater (2), a blower (3), a hot air gun (4), a water tank (9), a gear pump (10), an air compressor (8), a filter pressure reducer (7), a first manual valve (51), a second manual valve (52) and a third manual valve (53); The middle part of the dual-fluid urea direct injection pyrolysis spray gun (1) is installed inside the tubular heater (2); The outlet of the blower (3) is connected to the inlet of the hot air gun (4) via the first manual valve (51), and the outlet of the hot air gun (4) is connected to the hot air inlet of the tubular heater (2); The outlet of the water tank (9) is connected to the liquid pipeline inlet of the dual-fluid urea direct injection pyrolysis spray gun (1) via a gear pump (10); The outlet of the air compressor (8) is divided into two paths after passing through the filter pressure reducer (7), one of which is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun (1) through the second manual valve (52), and the other is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun (1) through the third manual valve (53); The outlet of the blower (3) is connected to the inlet of the hot air gun (4) via the first manual valve (51) and the first float flowmeter (61), and the outlet of the hot air gun (4) is connected to the hot air inlet of the tubular heater (2); The outlet of the water tank (9) is connected to the liquid pipeline inlet of the dual-fluid urea direct injection pyrolysis spray gun (1) via the gear pump (10) and the first pressure gauge (111); The outlet of the air compressor (8) is divided into two paths after passing through the filter pressure reducer (7), one of which is connected to the atomizing air interface of the dual-fluid urea direct injection pyrolysis spray gun (1) through the second manual valve (52), the second float flowmeter (62) and the second pressure gauge (112), and the other is connected to the cooling air interface of the dual-fluid urea direct injection pyrolysis spray gun (1) through the third manual valve (53) and the third float flowmeter (63); The tubular heater (2) comprises a round steel pipe and a connecting pipe, wherein the end of the connecting pipe is connected to the side of the rear end of the round steel pipe, the rear end of the round steel pipe is closed, the hot air gun (4) is inserted into the connecting pipe, a high-temperature electric heating wire is wound on the outer wall of the round steel pipe, and a heat-insulating cotton layer is wrapped on the outer wall of the round steel pipe. The middle part of the dual-fluid urea direct injection pyrolysis spray gun (1) is sleeved in the round steel pipe.

2. The urea direct injection pyrolysis spray gun characteristic test device according to claim 1 is characterized in that: The heating power of the hot air gun (4) is adjustable.

3. The urea direct injection pyrolysis spray gun characteristic test device according to claim 1 is characterized in that: A steel plate layer is arranged on the outer side of the thermal insulation cotton layer.

4. The urea direct injection pyrolysis spray gun characteristic test device according to claim 1, characterized in that: The middle part of the dual-fluid urea direct injection pyrolysis spray gun (1) is installed inside the tubular heater (2) through a flange.

5. A method for testing the characteristics of a urea direct injection pyrolysis spray gun, characterized in that: The urea direct injection pyrolysis spray gun characteristic test device according to claim 1 comprises the following steps: The air compressor (8), the filter pressure reducer (7), the second manual valve (52), and the third manual valve (53) are turned on to send cooling air and atomizing air into the dual-fluid urea direct injection pyrolysis spray gun (1); the blower (3) and the first manual valve (51) are turned on to send air into the hot air gun (4); the air is heated by the hot air gun (4) and then enters the round steel pipe; the electric heating wire is energized to measure the outlet air temperature of the round steel pipe; when the outlet air temperature of the round steel pipe reaches within a preset range, the gear pump (10) is turned on to pass liquid into the dual-fluid urea direct injection pyrolysis spray gun (1); the liquid is atomized by the atomizing air and then sprayed out.

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