Marine engine test bench exhaust after-treatment system

Abstract

The utility model discloses an exhaust gas after-treatment system for a marine engine test bench, comprising an exhaust main pipe of the test bench, several high-temperature butterfly valves, several electromagnetic switch valves, several temperature sensors, several pressure sensors, a blower, a one-way valve, a burner, an exhaust gas after-treatment integrated device, a particle collection box, a muffler and a PLC controller. The test bench input pipe is respectively connected to the exhaust main pipe of the test bench, one end of the exhaust pipe is vertically connected to one end of the exhaust main pipe of the test bench, and a burner and an exhaust gas after-treatment integrated device are sequentially arranged in the middle of the exhaust pipe. The utility model effectively removes pollutants in the exhaust main pipe of the test bench and solves the problem of "black smoke". The structure is compact, the layout space of the test bench is saved, and the exhaust gas purification efficiency when several marine engines are tested at the same time is significantly improved.

Description

Technical Field

[0001] The utility model relates to an engine test bench, in particular to an exhaust gas post-processing system of the test bench for marine diesel engines, dual-fuel engines, methanol engines and ammonia engines, belonging to the technical field of environmental protection. Background Art

[0002] With the continuous improvement of the International Maritime Organization's standards for ship pollutant emissions, marine engines are transforming and developing towards the field of low-carbon fuel (LNG, LPG, methanol, ammonia, etc.) engines. In recent years, the output of marine low-carbon / zero-carbon (natural gas, methanol, ammonia) fuel engines has accounted for an increasing proportion. In order to meet the emission regulations of the International Maritime Organization, most of the existing ship engines are equipped with exhaust gas after-treatment systems that match them. However, the types and contents of pollutants in the exhaust gas of engines with different fuels are significantly different, which makes the exhaust gas emissions of marine engines during test bench testing more complicated, and puts higher requirements on the exhaust gas after-treatment capabilities of the test bench. However, the existing environmental protection measures of marine engine test benches are relatively backward. When the marine engine is cold started or low-load tested, the emissions in the exhaust gas of the test bench exceed the standard. If it is not solved in time, it is very likely that the exhaust pollutants discharged by the test bench from the marine engine under test will exceed the standard, which will seriously affect the atmospheric environment, and will be punished by the environmental protection law enforcement department, and even ordered to suspend work and production for rectification, causing serious adverse effects and large economic losses. Utility Model Content

[0003] The purpose of the utility model is to provide a marine engine test bench exhaust gas post-treatment system to solve the problem of excessive exhaust gas discharged from the test bench during the marine engine test and polluting the atmospheric environment.

[0004] The utility model is realized through the following technical solutions:

[0005] A marine engine test bench exhaust gas after-treatment system comprises a test bench exhaust main pipe, several high-temperature butterfly valves, several electromagnetic switch valves, several temperature sensors, several pressure sensors, a blower, a one-way valve, a burner, an exhaust gas after-treatment integrated device, a particulate matter collection box, a muffler and a PLC controller, wherein the exhaust pipes of each marine engine under test are respectively connected to one end of the corresponding test bench input pipe, the test bench input pipe is respectively provided with a high-temperature butterfly valve, and the other end of the test bench input pipe is respectively connected to the test bench exhaust main pipe in the test workshop; one end of the exhaust pipe is vertically connected to one end of the test bench exhaust main pipe, a burner and an exhaust gas after-treatment integrated device are sequentially provided in the middle of the exhaust pipe, the other end of the exhaust pipe passes through the roof of the test workshop, and a muffler is installed in the outdoor section of the exhaust pipe; the other end of the test bench exhaust main pipe is connected to one end of the middle of the exhaust pipe through a bypass pipe, and the bypass pipe is provided with a bypass pipe high-temperature Butterfly valve; temperature sensors and pressure sensors are respectively connected to the exhaust pipes outside the two ends of the exhaust gas after-treatment integrated device; the blower output end is connected between the burner and one end of the exhaust pipe through a one-way valve; the fuel input pipe is connected to the burner through the first electromagnetic switch valve; a compressed air pipe is connected to the outer pipe at one end of the urea injector through the second electromagnetic switch valve; the urea solution delivery pipe is connected to the inner pipe at one end of the urea injector through the third electromagnetic switch valve; the other end of the urea injector extends into the vanadium-based catalyst section of the exhaust gas after-treatment integrated device; another compressed air pipe is connected to the upper side of the wall-flow stainless steel metal filter material honeycomb filter element of the exhaust gas after-treatment integrated device through the fourth electromagnetic switch valve; the particulate matter collection box is connected to the lower side of the wall-flow stainless steel metal filter material honeycomb filter element; the signal line of the PLC controller is respectively connected to the control end of each high-temperature butterfly valve and the control end of each electromagnetic switch valve.

[0006] The purpose of the utility model can be further achieved by the following technical measures.

[0007] Furthermore, the air volume of the blower is not less than 100m 3 / h, the electromagnetic switch valves are all normally closed valves.

[0008] Furthermore, the fuel input pressure is 0.2-0.3Mpa, and the maximum flow rate of the fuel input is 100L / h; the compressed air supply pressure is 0.5-0.8Mpa, and the maximum flow rate of the compressed air input is 30m 3 / h; the urea solution delivery pipe delivers 40% urea solution, the supply pressure of the urea solution is 0.2-0.3Mpa, and the maximum supply flow rate of the urea solution is 40L / h.

[0009] Furthermore, the temperature sensor has a temperature measurement range of -20°C to 800°C and outputs a 4-20mA signal; the pressure sensor has a pressure measurement range of 0-0.10kpa and outputs a 4-20mA signal. The maximum temperature resistance of the high-temperature butterfly valve is not less than 500°C.

[0010] Furthermore, the height H between the center of the smoke exhaust port of the outdoor section of the smoke exhaust pipe and the ground is greater than 30m.

[0011] The utility model can concentrate the exhaust gas discharged by several marine engines being tested at the same time into the exhaust main pipe of the test bench in the test workshop, and purify it through the exhaust gas post-treatment integrated device in the middle of the exhaust pipe before discharging it, effectively removing the pollutants in the exhaust main pipe of the test bench and solving the problem of "black smoke". The utility model has a compact structure, saves the layout space of the test bench, significantly improves the exhaust gas purification efficiency when several marine engines are tested at the same time, and makes the exhaust gas of the exhaust main pipe of the test bench meet the emission standards of ship pollutants that are constantly improved by the International Maritime Organization.

[0012] Advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments, which are given as examples only with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0015] like Figure 1 As shown, the exhaust gas after-treatment system of the marine engine test bench of the present embodiment includes a test bench exhaust main pipe 1, four high-temperature butterfly valves 2 with a maximum temperature resistance of not less than 500°C, four electromagnetic switch valves 3, two temperature sensors 4, two pressure sensors 5, a blower 6, a one-way valve 7, a burner 8, an exhaust gas after-treatment integrated device 9, a particulate matter collection box 10, a muffler 11 and a PLC controller 12. The eight exhaust pipes 100 of the three marine engines under test are respectively connected to one end of their corresponding test bench input pipes 13, and the test bench input pipes 13 are respectively provided with high-temperature butterfly valves 2. The other ends of the test bench input pipes 13 are respectively connected to the test bench exhaust main pipe 1 in the test workshop. One end of the exhaust pipe 14 is vertically connected to the left end of the exhaust main pipe 1 of the test bench. A burner 8 and an integrated exhaust gas after-treatment device 9 are arranged in sequence in the middle of the exhaust pipe 14. The other end of the exhaust pipe 14 passes through the roof 200 of the test workshop. A muffler 11 is installed in the outdoor section of the exhaust pipe 14. The right end of the exhaust main pipe 1 of the test bench is connected to the middle of the exhaust pipe 14 through a bypass pipe 18. A bypass pipe high-temperature butterfly valve 21 is arranged in the bypass pipe 18.

[0016] The exhaust gas aftertreatment integrated device 9 is divided into three sections connected to each other. The first section is a catalyst section 91 of a ceramic carrier. The carrier is usually a parallel honeycomb through-hole structure. The main components of the catalyst are precious metals such as Pt, rhodium (Rh) and palladium (Pd) in different proportions. The main function is to oxidize carbon monoxide and hydrocarbon pollutants into H2O and CO2 under the action of the catalyst. The second section is a vanadium-based catalyst section 92, which rapidly catalytically reacts with NO / NO2 on the catalyst surface of the urea reductant and the porous structure, and highly selectively reduces NOx to nitrogen (N2) and water. The third section is a wall-flow stainless steel metal filter material filter element 93, which has a honeycomb structure and can capture and collect PM particles in the exhaust gas to the greatest extent. The exhaust pipe 14 outside the two ends of the exhaust gas aftertreatment integrated device 9 is connected to the temperature sensor 4 and the pressure sensor 5 respectively. The output end of the blower 6 is connected between the burner 8 and one end of the exhaust pipe 14 through a one-way valve 7, and the fuel input pipe 16 is connected to the burner 8 through the first electromagnetic switch valve 31. A compressed air pipe 15 is connected to the outer pipe 171 at one end of the urea injector 17 through the second electromagnetic switch valve 32, and the urea solution delivery pipe 173 is connected to the inner pipe 172 at one end of the urea injector 17 through the third electromagnetic switch valve 33. The other end of the urea injector 17 extends into the vanadium-based catalyst section 92 of the exhaust gas post-treatment integrated device 9. Another compressed air pipe 15 is connected to the upper side of the wall-flow stainless steel metal filter material honeycomb filter element 93 through the fourth electromagnetic switch valve 34, and the particle collection box 10 is connected to the lower side of the wall-flow stainless steel metal filter material honeycomb filter element 93. The signal line 121 of the PLC controller 12 is respectively connected to the control end of each high-temperature butterfly valve 2 and the control end of each electromagnetic switch valve 3.

[0017] The air volume of blower 6 is not less than 100m 3 / h, the electromagnetic switch valve 3 is a normally closed valve. The fuel input pressure is 0.2-0.3Mpa, and the maximum flow rate of the fuel input is 100L / h; the compressed air supply pressure is 0.5-0.8Mpa, and the maximum flow rate of the compressed air input is 30m 3 / h; the urea solution delivery pipe 17 delivers 40% urea solution, the supply pressure of the urea solution is 0.2~0.3Mpa, and the maximum supply flow rate of the urea solution is 40L / h.

[0018] The temperature sensor 4 has a temperature measurement range of -20°C to 800°C and outputs a 4 to 20 mA signal. The pressure sensor 5 has a pressure measurement range of 0 to 0.10 kPa and outputs a 4 to 20 mA signal.

[0019] The height H between the center of the outdoor section of the smoke exhaust pipe 14 and the ground is greater than 30 m.

[0020] The process of using the utility model is as follows:

[0021] This embodiment can be used to simultaneously perform harmless treatment on exhaust gases emitted by three marine engines. The following takes the harmless treatment of exhaust gases emitted by one marine engine as an example, and the harmless treatment of exhaust gases emitted by the other two marine engines is the same.

[0022] Before starting the A marine engine: if the first temperature sensor 41 outside the left end of the exhaust gas after-treatment integrated device 9 detects that the temperature of the catalyst in the exhaust gas after-treatment integrated device 9 is lower than the required minimum temperature of 260°C, the PLC controller 12 instructs the blower 6 to start, and fresh air enters the lower side of the burner 8. At the same time, the PLC controller 12 instructs the first electromagnetic switch valve 31 to be opened, and the fuel is injected into the burner 8 through the fuel input pipe 16 to burn to heat the exhaust gas after-treatment integrated device 9. After heating for 20 minutes and the second temperature sensor 42 outside the right end of the exhaust gas after-treatment integrated device 9 detects that the exhaust temperature exceeds 200°C, the PLC controller 12 instructs the blower 6 and the first electromagnetic switch valve 31 to be closed. At this time, the marine engine has met the test start requirements;

[0023] After the B marine engine is started: the PLC controller 12 instructs to open the high-temperature butterfly valve 2 in the corresponding test bench input pipe, and the exhaust gas of the test marine engine enters the test bench exhaust main pipe 1 through the corresponding test bench input pipe 15, and then enters the exhaust gas after-treatment integrated device 9. At this time, the PLC controller 12 instructs to open the second electromagnetic switch valve 32 and the third electromagnetic switch valve 33 respectively, and the compressed air enters the outer pipe 171 at one end of the urea injector 17 through a compressed air pipe 15, and the urea solution enters the inner pipe 172 at one end of the urea injector 17. After the exhaust gas discharged from the marine engine passes through the exhaust gas after-treatment integrated device 9, the carbon monoxide, hydrocarbons, nitrogen oxides and particulate matter in the exhaust gas are effectively eliminated, and then the exhaust gas is discharged through the muffler 11 in the exhaust pipe 14.

[0024] When the C marine engine is shut down, the PLC controller 12 instructs to close the second electromagnetic switch valve 32 and the third electromagnetic switch valve 33, respectively, to cut off the supply of compressed air and urea solution, and then shut down the marine engine after the marine engine continues to run stably for 10 minutes to prevent the exhaust pipe from being blocked by crystals due to insufficient urea thermal decomposition and hydrolysis;

[0025] During the operation of the D1 marine engine: When the first pressure sensor 51 and the second pressure sensor 52 detect that the pressure difference between the two ends of the exhaust gas post-treatment device 9 exceeds 20kpa, the PLC controller 12 instructs the fourth electromagnetic switch valve 34 to be opened, and the high-pressure compressed air of 0.5-0.8Mpa enters the exhaust gas post-treatment integrated device 9 through another compressed air pipe 15 for back-blowing treatment, and the cleaned particles fall into the particle collection box 10 under the action of gravity. When the pressure difference between the two ends of the exhaust gas post-treatment device is lower than 15kpa, the PLC controller instructs the fourth electromagnetic switch valve 34 to be closed, and the high-pressure compressed air stops back-blowing treatment.

[0026] D2 During the operation of the marine engine: when the first pressure sensor 51 and the second pressure sensor 52 detect that the pressure difference between the two ends of the exhaust after-treatment device 9 exceeds 30kpa, the PLC controller 12 instructs the second electromagnetic switch valve 32, the third electromagnetic switch valve 33 and the fourth electromagnetic switch valve 34 to be closed respectively, cutting off all high-pressure compressed air and urea solution; at the same time, the PLC controller 12 instructs the bypass pipe high-temperature butterfly valve 21 in the bypass pipe 18 to be opened to ensure normal test run of the marine engine.

[0027] In addition to the above-mentioned embodiments, the present invention may also have other implementation modes. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present invention.

Claims

1. An exhaust gas after-treatment system for a marine engine test bench, characterized in that: It includes a test bench exhaust main pipe, several high-temperature butterfly valves, several electromagnetic switch valves, several temperature sensors, several pressure sensors, a blower, a one-way valve, a burner, an exhaust gas after-treatment integrated device, a particulate matter collection box, a muffler and a PLC controller. The exhaust pipes of each marine engine under test are respectively connected to one end of the corresponding test bench input pipe, and the test bench input pipe is respectively provided with a high-temperature butterfly valve. The other end of the test bench input pipe is respectively connected to the test bench exhaust main pipe in the test workshop; one end of the exhaust pipe is vertically connected to one end of the test bench exhaust main pipe, and a burner and an exhaust gas after-treatment integrated device are successively provided in the middle of the exhaust pipe. The other end of the exhaust pipe passes through the roof of the test workshop, and a muffler is installed in the outdoor section of the exhaust pipe; the other end of the test bench exhaust main pipe is connected to one end of the middle of the exhaust pipe through a bypass pipe, and the bypass pipe is provided with a bypass pipe high-temperature butterfly valve; The exhaust pipes outside the two ends of the integrated device are respectively connected to a temperature sensor and a pressure sensor, the output end of the blower is connected between the burner and one end of the exhaust pipe through a one-way valve, the fuel input pipe is connected to the burner through a first electromagnetic switch valve, a compressed air pipe is communicated with an outer pipe at one end of the urea injector through a second electromagnetic switch valve, a urea solution delivery pipe is communicated with an inner pipe at one end of the urea injector through a third electromagnetic switch valve, the other end of the urea injector extends into the vanadium-based catalyst section of the exhaust gas after-treatment integrated device, another compressed air pipe is connected to the upper side of the wall-flow stainless steel metal filter material honeycomb filter element of the exhaust gas after-treatment integrated device through a fourth electromagnetic switch valve, and a particulate matter collection box is connected to the lower side of the wall-flow stainless steel metal filter material honeycomb filter element; the signal line of the PLC controller is respectively connected to the control end of each high-temperature butterfly valve and the control end of each electromagnetic switch valve.

2. The marine engine test bench exhaust gas after-treatment system according to claim 1, characterized in that: The air volume of the blower is not less than 100m 3 / h.

3. The marine engine test bench exhaust gas after-treatment system according to claim 1, characterized in that: The electromagnetic switch valves are all normally closed valves.

4. The marine engine test bench exhaust gas after-treatment system according to claim 1, characterized in that: The fuel input pressure is 0.2-0.3Mpa, and the maximum flow rate of fuel input is 100L / h; the compressed air supply pressure is 0.5-0.8Mpa, and the maximum flow rate of compressed air input is 30m 3 / h; the air volume of the blower is not less than 100m 3 / h; the urea solution is a 40% urea solution, the supply pressure of the urea solution is 0.2-0.3Mpa, and the maximum supply flow rate of the urea solution is 40L / h.

5. The marine engine test bench exhaust gas after-treatment system according to claim 1, characterized in that: The temperature sensor has a temperature measurement range of -20°C to 800°C and outputs 4 to 20mA signals; the pressure sensor has a pressure measurement range of 0 to 0.10kpa and outputs 4 to 20mA signals; the maximum temperature resistance of the high-temperature butterfly valve is not less than 500°C.

6. The marine engine test bench exhaust gas after-treatment system according to claim 1, characterized in that: The height H of the center of the outdoor section of the smoke exhaust pipe from the ground is greater than 30m.

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