CN-117231327-B - Post-treatment ultrasonic fuel atomization regeneration system and method for marine diesel engine

CN117231327BCN 117231327 BCN117231327 BCN 117231327BCN-117231327-B

Abstract

The invention relates to a ship diesel engine post-treatment ultrasonic fuel atomization regeneration system and a method, comprises an ultrasonic atomizer, an oil supply system, a pipeline system, an atomization mixing chamber, a post-treatment system and a control system. The control system is controlled by the ECU. The ultrasonic atomizer can atomize diesel into small-particle-size flammable steam, so that the combustion efficiency is improved and the emission is reduced. And when the DPF needs to be regenerated, an air inlet and exhaust control valve of the aftertreatment system is opened, tail gas and diesel steam are mixed, catalytic reaction occurs in the DOC, heat is released, the temperature of a DPF reaction bed is increased, and particulate matters are ignited and stored, so that DPF regeneration is realized. The regeneration system is flexibly designed, can be used for ship diesel oil or is connected with an independent oil tank, and has wide applicability. The invention is environment-friendly, efficient, reliable and easy to use, and provides an innovative solution for the emission control of the marine diesel engine.

Inventors

DENG YANGBO
BAI YUXUAN
Jia Qiaoxi
JIANG HAO
LIU SHIXU
ZHU SHUYU
JIN JITAO

Assignees

大连海事大学

Dates

Publication Date: 20260508
Application Date: 20230911

Claims (7)

1. The utility model provides a marine diesel aftertreatment ultrasonic wave fuel atomizing regeneration system which characterized in that, includes ultrasonic atomizer, oil feeding system, pipe-line system, atomizing mixing chamber, catalytic oxidation device DOC, particle trap DPF, temperature sensor, differential pressure sensor, particulate matter concentration sensor, humidity transducer, electronic control unit ECU, intake control valve, exhaust control valve, wherein: The ultrasonic atomizer is arranged in the atomization mixing chamber and is used for realizing the atomization of diesel; the output end of the oil supply system is connected with the atomization mixing chamber and is used for providing diesel oil to the atomization mixing chamber; The atomization mixing chamber is positioned on a main pipeline at the upstream of the catalytic oxidation device DOC, and the air inlet control valve and the exhaust control valve are arranged between the atomization mixing chamber and the main pipeline; When the particle catcher DPF needs to be regenerated, an electronic control unit ECU controls the opening of an air inlet control valve and an exhaust control valve, part of tail gas flows into an atomization mixing chamber, mixed diesel oil steam flows out, and main stream tail gas is gathered to enter the DOC of the catalytic oxidation device for combustion, so that the temperature of a reaction bed of the particle catcher DPF is increased to ignite and store particles, and the regeneration of the particle catcher DPF is realized; The output end of the catalytic oxidation device DOC is connected with a particle catcher DPF, and the catalytic oxidation device DOC is used for carrying out catalytic reaction on gas mixed by tail gas and diesel steam and releasing heat; The temperature sensor is used for measuring temperature information of a preset point on a main pipeline, the differential pressure sensor is used for measuring exhaust backpressure of the particle catcher DPF, the particle concentration sensor is used for monitoring concentration of particles discharged by the particle catcher DPF, the humidity sensor is arranged at the upper position in the ultrasonic atomizer and used for monitoring concentration of atomized mixed gas in the atomized mixing chamber, the sensors are connected with the electronic control unit ECU, the electronic control unit ECU is connected with the air inlet control valve and the exhaust control valve, and the opening states of the air inlet control valve and the exhaust control valve are controlled based on data transmitted by the sensors; specifically, tail gas enters an ultrasonic fuel oil atomization regeneration system of a marine diesel engine through a gas transmission pipeline from a gas inlet, the temperature at the DOC inlet of a catalytic oxidation device is measured through a first temperature sensor, and an electronic control unit ECU monitors and feeds back real-time data to judge whether a regeneration system control strategy is performed; If a regeneration system control strategy is needed, an electronic control unit ECU controls to open an inlet control valve, tail gas enters an atomization mixing chamber from the inlet control valve, the electronic control unit ECU controls a fuel oil shutoff electromagnetic valve to be opened, an oil pump controls an oil pump to pump diesel oil in an oil tank, the diesel oil flows through a fuel filter to enter the atomization mixing chamber, the electronic control unit ECU controls an ultrasonic atomizer to work, the diesel oil is atomized into fuel steam and is mixed with the tail gas flowing into the atomization mixing chamber, the temperature of the mixed steam is increased, and the diesel oil enters a catalytic oxidation device DOC through an exhaust control valve to complete a regeneration process; According to real-time data monitored and fed back by the electronic control unit ECU, the first temperature sensor, the second temperature sensor, the third temperature sensor, the differential pressure sensor, the particulate matter concentration sensor, the humidity sensor and the liquid level control sensor, a regeneration system control strategy is carried out, the steps are repeated, and the tail gas is treated until the treated tail gas is discharged from an exhaust port; The method comprises the steps of measuring the temperature T1 of a DOC inlet of a catalytic oxidation device through a first temperature sensor, measuring the temperature T2 of a DPF inlet of a particle catcher through a second temperature sensor, measuring the temperature T3 of a DPF outlet of the particle catcher through a third temperature sensor, when the temperature T1 is lower than 300 ℃, adopting in-cylinder measures and exhaust gas circulation heating measures to enable the temperature of an exhaust pipe to reach 300 ℃, so that the conversion efficiency of the DOC is fully activated, when the temperature T1 is higher than 300 ℃, opening an inlet and outlet control valve to atomize fuel in an atomization mixing chamber, improving the exhaust temperature through combustion, when the temperature T2 is lower than a critical temperature Tcr, controlling the working frequency and electric energy output of an ultrasonic atomizer to control the concentration of fuel atomization mixed gas, when the temperature T2 is higher than the critical temperature Tcr, closing an inlet and outlet control valve and the ultrasonic atomizer, stopping fuel supply through a fuel shutoff electromagnetic valve, and when the temperature T3 is higher than a safe temperature resistant threshold Tsafe of the DPF, sending a fault signal through the electronic control unit ECU.
2. The post-treatment ultrasonic fuel atomization regeneration system of the marine diesel engine according to claim 1, wherein the ultrasonic atomizer is made of a micro piezoelectric vibrating piece, and the vibrating piece generates ultrasonic waves by contacting with diesel oil, and the ultrasonic waves act to atomize the diesel oil into finer mist droplets, thereby realizing the atomization of the diesel oil.
3. The post-treatment ultrasonic fuel atomization regeneration system of the marine diesel engine according to claim 1, wherein the ultrasonic atomizer adopts an ultrasonic generator with the oscillation frequency of high frequency 110 KHz+/-3 KHz, the structure of the ultrasonic generator comprises a plurality of atomization units, the ultrasonic generator and an atomizer control device, each atomization unit consists of a plurality of micropore atomization sheets, each micropore atomization sheet consists of piezoelectric ceramics and a metal membrane, the surface of each micropore atomization sheet is provided with a tiny concave-convex texture, the center part of each micropore atomization sheet comprises a tiny hole structure, the opening quantity of the ultrasonic atomization units can be controlled, the ultrasonic generator is used as equipment for supplying high-frequency electric energy and is used for driving ultrasonic waves in the atomizer, and the ultrasonic atomization diesel oil control device is controlled by an electronic control unit ECU and is used for adjusting the working frequency, the electric energy output and the opening quantity of the ultrasonic generator.
4. The post-treatment ultrasonic fuel atomization regeneration system of the marine diesel engine according to claim 1, wherein the fuel supply system comprises a fuel tank, a fuel filter, an oil pump, a fuel shut-off electromagnetic valve and a liquid level control sensor in an atomization mixing chamber, diesel oil in the fuel tank flows through the fuel filter to enter the atomization mixing chamber by controlling the fuel shut-off electromagnetic valve through the oil pump, the liquid level control sensor is connected with an electronic control unit ECU, the output state of the fuel supply system is controlled based on data provided by the liquid level control sensor, the proportion of the supply of the diesel oil to the mixed diesel oil steam is ensured, and a drain bolt is arranged at the bottommost part of the atomization mixing chamber.
5. The marine diesel aftertreatment ultrasonic fuel atomization regeneration system of claim 1, wherein the temperature sensor comprises a first temperature sensor configured to measure a catalytic oxidation device DOC inlet temperature, a second temperature sensor configured to measure a particle trap DPF inlet temperature, and a third temperature sensor configured to measure a particle trap DPF outlet temperature.
6. The marine diesel aftertreatment ultrasonic fuel atomization regeneration system of claim 1, wherein the source of diesel fuel in the fuel supply system comprises a direct connection to a marine fuel supply system or a stand-alone tank.
7. The ultrasonic fuel atomization regeneration system for post-treatment of a marine diesel engine according to claim 1, wherein the Electronic Control Unit (ECU) collects the exhaust pressure difference P measured by the pressure difference sensor and the trapping operation time t of the particle trap DPF in real time, compares the collected exhaust pressure difference P and the trapping operation time t with set upper limit values Pmax and tmax, and judges whether the upper limit value is exceeded; If the exhaust pressure difference P is larger than the set upper limit value Pmax or the time t is larger than the set upper limit value tmax, the particle trap DPF needs to be regenerated, if the exhaust pressure difference P and the time t do not reach the upper limit value, the particle trap DPF does not need to be regenerated, the time t is reset after the regeneration is finished, and the exhaust pressure difference is measured again.

Description

Post-treatment ultrasonic fuel atomization regeneration system and method for marine diesel engine Technical Field The invention relates to the technical field of treatment of pollutants discharged by a diesel engine, in particular to a ship diesel engine post-treatment ultrasonic fuel atomization regeneration system and a method. Background The emission of the marine particulates causes serious pollution to the coastal area environment, and the emission treatment of the particulates is an important content for controlling the marine diesel engine pollutants. Diesel particulate traps (DPFs) are currently recognized as efficient devices that reduce Particulate Matter (PM) emissions. Diesel fuel, when combusted in a cylinder, produces PM that contaminates the atmosphere, and when passing through a DPF, is trapped and deposited therein. When the amount of PM deposited exceeds a certain amount, the exhaust pipe is clogged, and the power performance of the diesel engine is affected. The PM accumulated in the DPF passage is removed, and the trapping ability of the DPF is recovered, which is called DPF regeneration. In order to increase the regeneration temperature value in the DPF, a diesel catalytic oxidation Device (DOC) assisted DPF regeneration method is generally used. And when the temperature of the exhaust gas of the DOC exceeds 300 ℃, unburned hydrocarbon is generated by spraying certain diesel oil or diesel engine cylinder and then spraying, so that the oxidation exothermic reaction of the unburned matter in the DOC is realized, the oxidation exothermic reaction is used for providing the temperature rising heat of the exhaust gas, and DPF regeneration is realized. The catalyst coated DPF has a temperature of 300 degrees Celsius or more to ignite the PM deposited in the DPF. It is difficult to experiment DPF regeneration due to low exhaust temperatures of marine diesel engines. Disclosure of Invention According to the technical problems, the system and the method for after-treatment ultrasonic fuel atomization regeneration of the marine diesel engine are provided. The invention adopts the following technical means: the utility model provides a marine diesel aftertreatment ultrasonic wave fuel atomization regeneration system, includes ultrasonic atomizer, oil feeding system, pipe-line system, atomizing mixing chamber, catalytic oxidation device DOC, particle catcher DPF, temperature sensor, differential pressure sensor, particulate matter concentration sensor, humidity transducer, electronic control unit ECU, inlet control valve, exhaust control valve, wherein: The ultrasonic atomizer is arranged in the atomization mixing chamber and is used for realizing the atomization of diesel; the output end of the oil supply system is connected with the atomization mixing chamber and is used for providing diesel oil to the atomization mixing chamber; The atomization mixing chamber is positioned on a main pipeline at the upstream of the catalytic oxidation device DOC, and the air inlet control valve and the exhaust control valve are arranged between the atomization mixing chamber and the main pipeline; The output end of the catalytic oxidation device DOC is connected with a particle catcher DPF, and the catalytic oxidation device DOC is used for carrying out catalytic reaction on gas mixed by tail gas and diesel steam and releasing heat; The temperature sensor is used for measuring temperature information of a preset point position on a main pipeline, the pressure difference sensor is used for measuring exhaust backpressure of the particle catcher DPF, the particle concentration sensor is used for monitoring concentration of particles discharged by the particle catcher DPF, the humidity sensor is arranged at the upper position in the ultrasonic atomizer and used for monitoring concentration of atomized mixed gas in the atomized mixing chamber, the sensor is connected with the electronic control unit ECU, the electronic control unit ECU is connected with the air inlet control valve and the exhaust control valve, and the opening states of the air inlet control valve and the exhaust control valve are controlled based on data transmitted by the sensor. Further, the ultrasonic atomizer is made of a micro piezoelectric vibrating piece, and the vibrating piece is contacted with diesel oil to generate ultrasonic waves, so that the ultrasonic waves act to atomize the diesel oil into finer mist drops, and the atomization of the diesel oil is realized. Further, the ultrasonic atomizer adopts an ultrasonic generator with oscillation frequency of 110 KHz+/-3 KHz, the structure of the ultrasonic generator comprises a plurality of atomization units, an ultrasonic generator and an atomizer control device, each atomization unit consists of a plurality of microporous atomization sheets, each microporous atomization sheet consists of piezoelectric ceramics and a metal membrane, the surface of each microporous atomization sheet is provid